Dynamic Deserts Resource Uncertainty in Arid Environments

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The Second Annual Frontiers in Life Sciences Conference Dynamic Deserts Resource Uncertainty in Arid Environments

February 26 - March 1, 2009 Arizona State University School Of Life Sciences Old main, Carson Ballroom, Tempe Campus table of contents Acknowledgements...... 1

Guest Speaker Biographies ...... 2

Conference Organizers...... 8

Speaker Abstracts...... 10

Poster Abstracts...... 26 conference overview A timely, multidisciplinary conference on resource uncertainty in arid systems, Dynamic Deserts: Resource Uncer- tainty in Arid Environments is a graduate student proposed and organized conference supported by the Frontiers in Life Sciences program in Arizona State University’s School of Life Sciences . The purpose of this conference is to share knowledge and analytical approaches that address the unifying theme of resource uncertainty in deserts across multiple scales of biological and socioecological organization . This event promotes international, cross-disciplinary collaboration among leading scientists and graduate students along with natural resource managers, policy makers, and educators to generate both academic and applied advances . We invite you to join us for this exciting event February 26 – March 1, 2009 at Old Main, Carson Ballroom, Tempe Campus . acknowledgements Dynamic Deserts: Resource Uncertainty in Arid Environments would not have been possible without support from the following sponsors:

• School of Life Sciences Research and Training Initiatives Committee

• Decision Center for a Desert City (DCDC)

• Arizona State University’s Graduate and Professional Student Association (GPSA)

• Central Arizona – Phoenix Long Term Ecological Research (CAP-LTER)

• Arizona State University’s Global Institute of Sustainability (GIOS)

• Arizona State University’s School of Sustainability (SOS) City of Tempe Water Utilities Department

We would also like to take this opportunity to thank the School of Life Sciences for their valuable assistance in making this conference a success .

• Rhonda Chapman, School of Life Sciences Business Office

• Margaret Coulombe, School of Life Sciences Research

• Proposal / Media Relations conference • Sabine Deviche, School of Life Sciences Visualization Lab • Anita Dubbs, School of Life Sciences Business Office overview • James Elser, Associate Director, School of Life Sciences • Research and Training Initiatives

• Rachel Hayes, School of Life Sciences Business Office

• Charles Kazilek, School of Life Sciences Visualization Lab

• Jacob Mayfield, School of Life Sciences Visualization Lab

• Jacob Sahertian, School of Life Sciences Visualization Lab

We would like to thank the following for their assistance with the PhotoGraphy Workshop .

• Mark Klett, Regent’s Professor of Art (Photography), Arizona State University

• Nancy Grimm, School of Life Sciences, Arizona State University

• Marcia Nation, CAP Project manager, Global Institute of Sustainability

• Brenda Shears, Associate Director Operations and Research Support, Global Institute of Sustainability

• Barry Sparkman, Arts and Humanities Liaison, Global Institute of Sustainability

1 guest speakers

Keynote Speaker: Dr. Michael Rosenzweig Dr. Mark Klett Trained as a geologist, has spent his career exploring and Mark Klett established his artistic explaining patterns of species diversity perspective on the western American from local to regional scales . By examining landscape as the chief photographer species-area relationships and other for the Rephotographic Survey Project determinants of species diversity, Dr . (1977-1979), which rephotographed Rosenzweig has synthesized information scenes visited by the first photographic and developed mathematical theories surveys of the West in the 1860s and that are the basis of much modern 1870s . Klett’s landscape photographs ecological research regarding diversity have become icons of today’s Southwest, patterns . He is also the author of celebrating its raw beauty while tackling “Win-Win Ecology: How Earth’s Species such volatile issues as land and water Can Survive in the Midst of Human use . The Old West battle between the Enterprise”, a thought-provoking look white hats and black hats has segued at how we can maintain species diversity into developer versus preservationist . He in human dominated environments . has used his large-format camera and tripod to document the interaction of Dr. Larry Venable and students in his man and desert . lab study plant population and community dynamics and plant reproductive ecology . Dr. Rimjhim Aggarwal’s research explores We currently focus on the population global dimensions of sustainability such dynamics of desert winter annual plants . as the links between globalization, local Larry’s theoretical work on plant reproductive ecosystems, and poverty in less-developed ecology deals with aspects of dormancy, countries . She has conducted extensive dispersal, sex allocation, pollen evolution, field work on groundwater-irrigation seed size, hierarchical packaging of institutions in India; her recent research reproduction, and the evolution of examines the emerging tradeoffs between inflorescence design . He is investigating water availability and the growing demands the evolution of leaves and sexual of agriculture in dry-land regions of the world . systems in a speciose Mexican tree genus, and gender evolution in a Sonoran Dr. J. Marty Anderies-My current Desert shrub . He also works on seed research interests focus on robust morphometrics and adaptive geographic management and robust institutional differentiation in a seed heteromorphic design for coupled social-ecological Mexican annual plant . systems . I study a range of archaeological, historical, and present-day examples of social-ecological systems using formal mathematical modeling and analysis to

2 photo credit: Junkyarksparkle

develop an understanding of ecological, Dr. Julio Betancourt-The main objective behavioral, social, and institutional of Dr . Betancourt’s research is to study factors that generate vulnerability and/or ecosystem and watershed responses enhance resilience and robustness in to climate variability on different temporal social-ecological systems . Other areas and spatial scales . More often than not, of interest include economic growth, these responses can only be studied demographics, and the environment and understood in retrospect and at and mathematical modeling in regional to subcontinental scales . Along community ecology . with close colleagues and students, Dr . Betancourt has contributed to networks Dr. Jayne Belnap-Over the past 20 years, of rodent midden and tree-ring data in Dr . Belnap has published 175 peer- the Americas . They have always made a reviewed articles and books on biological point of applying this historical knowledge soil crusts and dryland ecology that include not only to fundamental questions of a BLM technical reference (co-authored science, but also to contemporary issues with 3 other BLM scientists) and the facing management of water and other only comprehensive book available on resources . the topic . She is recognized by scientists around the globe as one of world’s Dr. Scott Collins is a community ecologist authorities on soil crusts . Dr . Belnap has broadly interested in vegetation dynamics been invited by many governments to from the patch to landscape scale . As train their scientists in soil crust ecology, Director of the Sevilleta LTER, Dr . Collins including those of South Africa, Kenya, leads a variety of studies on the roles of Zimbabwe, Mongolia, China, Siberia, plant-soil feedbacks, climatic variation, Australia, and Iceland . She travels and disturbance in driving long-term extensively throughout the U . S ., training dynamics of desert grasslands and shifts BLM, NPS, USFS, BIA, DoD, and DOE from range to shrublands . staff and managers on management of soil crusts . She is past Chair of the Soil Dr. Douglas B. Craig’s research interests Ecology chapter of Ecological Society cover a range of topics related to the of America, past President-Elect of the prehistory of the U .S ./Mexico borderlands Soil Ecology Society, and past member region . His published studies have of the Governing Board of Ecological focused on the political ecology of early Society of America . farming communities, in particular, the relationship between environmental variation, agricultural productivity, and the rise of social inequality . Dr . Craig has also been active in efforts to model

3 prehistoric population dynamics across Dr . Frisvold served on the Senior staff the region . He and his colleagues are of the President’s Council of Economic currently conducting investigations at Advisers with responsibility for agricultural, several early farming settlements along natural resource, and international the San Pedro and Santa Cruz rivers . trade issues . Currently, he serves as Co-Editor of the Journal of Agricultural Dr. Dale DeNardo is interested in how and Resource Economics . animals use their environment to meet physiological needs . Of particular Dr. Nancy Grimm’s research concerns interests are the trade-offs associated the structure and function of ecosystems with balancing multiple physiological in arid lands . Her current research focus traits such as thermoregulation, water is on the cycling and retention of the balance, energy balance, and reproduction . element nitrogen, considered in Dr . DeNardo integrates laboratory the context of patch dynamics and studies with field studies to provide a landscape heterogeneity . Current projects balance of controlled experimentation in Dr . Grimm’s research group are and ecological relevance . By doing 1) plant-microbe-soil interactions and such, critical components of the nitrogen transformations in a riparian environment can be identified and ecosystem (San Pedro River, AZ; SAHRA regulatory mechanisms can be unveiled . project); 2) nitrate retention (using The majority of studies involve squamate stable isotope experiments) in urban, reptiles (lizards and snakes) of the agricultural, and unmodified streams of Sonoran Desert . the American Southwest (LINX-2 project); 3) biogeochemistry and hot spots of N Dr. David Eldridge’s research covers transformation in urban landscapes; the broad areas of rangeland ecology, and 4) effects of urban atmospheric specifically the effects of animals deposition on biogeochemical cycling in (ecosystem engineers) on soil processes, deserts (Urban BGC project) . Dr . Grimm ecology of desert soil crusts, and is Co-Director of the Central Arizona- monitoring of soil and rangeland health . Phoenix Long-Term Ecological Research The focus of his research is on the Project (CAP LTER), an ecological study semi-arid woodlands of eastern Australia; of the Phoenix metropolitan area . he also maintains long-term research interests in west-central Idaho and the Dr. J. Nathaniel Holland‘s Research in south-western Chihuahuan desert in the Holland laboratory is centered around the western United States . the ecology and evolution of interspecific interactions . We are particularly interested Dr. George Frisvold has joined the in the influences of mutualism on patterns faculty at The University of Arizona in and processes across populations, 1997 . He has been a visiting scholar at communities, and ecosystems . Our aim the National Institute of Rural Development is to develop a mechanistic understanding in Hyderabad, India, a lecturer at The of these patterns and processes, ranging Johns Hopkins University, and Chief from the ecological and evolutionary of the Resource and Environmental stability of pairwise mutualisms to the Policy Branch of USDA’s Economic structure and dynamics of multi-species Research Service . His research mutualistic networks . We are interested interests include domestic and international in a wide range of mutualisms, but our environmental policy, as well as the studies most commonly involve plant- causes and consequences of technological insect interactions, particularly in the change in agriculture . In 1995-96, Sonoran Desert .

4 Dr. Burt Kotler‘s research ranges from of plant individuals, populations and community and evolutionary ecology assemblages • Invasive species • to animal behavior . He studies the Plant-plant interactions in arid and consequences of natural selection at the semi-arid ecosystems • Plant-biological community level on foraging behavior and soil crusts interactions in arid and coexistence mechanisms of granivorous semi-arid ecosystems • Role of biological desert birds and mammals, desert rodents soil crusts in the functioning of semi-arid and their predators, and habitat quality ecosystems • Spatial heterogeneity of and interactions among African herbivores . soil properties and plant performance at He applies foraging theory, predator-prey different scales • Relationships between foraging games, and behavioral indicators ecosystem structure/composition and to conservation issues, particularly in functioning in semi-arid ecosystems • arid environments . Dr . Kotler is subject Spatial analysis of ecological data editor for Ecology, Ecological Monographs • Environmental conservation and industrial and Annales Zoologici and editor-in-chief development in the town of Sax (Spain) . for Israel Journal of Ecology and Evolution . He is a highly cited author on ISI Web Dr. Maria Miriti’s research incorporates of Science . theoretical, experimental and demographic methods to address factors that regulate Dr. Claudio Latorre’s area of research plant populations and communities . lies within the realms of Paleoecology/ Because plants are immobile and habitats Paleoclimatology and Plant Biogeography are heterogeneous, the individual as applied to arid regions . His current responses of plants to patchy resource research deals with the modern flora distribution will influence the spatial and Quaternary paleoflora of the Atacama distribution of community members . The Desert and the Pacific slope of the Andes local environment of individuals differs of northern Chile . Over the last few years, from the average environment of the Dr . Latorre and his collaborators and have population and will influence population been using midden records from the dynamics . An important question is: Atacama to address key questions regarding How do individualistic responses of this desert’s hydrological cycle over plants affect population, community, the last 40,000-50,000 years . As our and ecosystem processes? Dr . Miriti knowledge on the distribution and addresses this question by merging diversity of past desert plant communities information on the spatial distribution in northern Chile increases, Dr . Latorre of resources and the differential responses and colleagues seek to understand the of neighboring individuals to the spatial implications for biogeography and characteristics of their environment . eventually, conservation of modern desert communities, many of which Dr. Gary Paul Nabhan, PhD., is an have been highly dynamic through time . Arab-American writer, lecturer, food and farming advocate, rural lifeways folklorist, Dr. Fernando Maestre-I am interested and conservationist whose work has on a wide variety of topics that vary from long been rooted in the U .S ./Mexico the impacts of ongoing global changes borderlands region he affectionately on plant-plant interactions to the role calls “the stinkin’ hot desert .” He of biological soil crusts in the functioning recently accepted a tenured professorship of semi-arid ecosystems . My major as a Research Social Scientist based at research areas, current and past, include: the Southwest Center of the University Interactive effects of global change drivers of Arizona--- his alma mater . He teaches and soil heterogeneity on the performance in Geography, as well as interacts with

5 faculty and graduate students engaged and semiarid regions of the globe; and in creative writing and reconciliation (2) whole plant growth modeling: these ecology research . He continues advising plant growth models are incorporated or consulting with many non-profits, into ecosystem models to explore including the Renewing America’s Food questions related to climate change, Traditions collaborative . e g. ., how elevated CO2 levels will affect carbon sequestration and nitrogen Charles Perrings directs (with Ann cycling in arid ecosystems . Currently, I Kinzig) the ecoSERVICES group at ASU am collaborating with researchers at the and co-chairs (with Shahid Naeem) the Nevada Desert FACE [Free-Air-Carbon ecoSERVICES core project of Diversitas, dioxide-Enrichment] Facility in Las Vegas . the international program of biodiversity science . The Group contributes to a number Dr. Stan Smith is a plant physiological of international research projects on ecologist who has spent the past 25 issues relating to biodiversity change, years studying how desert plants adapt conservation and development, and to the stressful environments that they supports training in biodiversity and occupy . Over the past 5 years, his lab ecosystem services both within ASU group has concentrated on how global and internationally . Dr . Perrings is Past change factors, particularly elevated President of theInternational Society for atmospheric CO2, affect the structure Ecological Economics and has advised and function of desert ecosystems . various governmental, intergovernmental Their research spans a variety of scales, and international non-governmental from membrane-level physiology to organizations as well as research ecosystem processes . Most of our current funding agencies . In Britain he served research occurs at the Nevada Desert on, inter alia, the Royal Society’s FACE Facility, a whole-ecosystem CO2 Environment Committee, the WHAT manipulation experiment supported by Commission on Crop Genetic Diversity the Department of Energy . They are also in Agriculture and the Centre for Ecology addressing how land use, nitrogen and Hydrology (Natural Environment deposition, and altered precipitation Research Council Research Institutes) patterns may affect desert ecosystems . Program Review Board . Dr. Katherine A. Spielmann’s research Dr. James Reynolds-My current interests focus on prehistoric economies interests center on the response of in smaller-scale societies, primarily plants and ecosystems to disturbance, in North America . She is especially e .g ., climate change and human land interested in the ways in which economic use . I am interested in both theoretical intensification is fueled by increasing and empirical approaches, and use demands for food and goods in ritual, mathematical and computer modeling political and social contexts . One of her extensively in my research . My current primary contributions to the discipline research deals with (1) desertification: has been to demonstrate the variety of As a co-PI of the NSF-supported Center conditions under which small-scale for the Integrated Study of the Human societies with relatively non-complex Dimensions of Global Change (Carnegie political systems develop complex, Mellon University), I am leading an specialized economies . She is also international research team that is interested in the relationship between developing an integrated assessment diet and health under different model for rangeland degradation in arid subsistence regimes .

6 Dr. Glenn Walsberg-Research in Dr. Blair Wolf is an ecophysiologist the Walsberg laboratory focuses studying the flow of energy and on the environmental physiology and resources through desert foodwebs . biophysical ecology of birds and He employs cutting-edgeisotopic mammals . Major topics of research and ultrasound techniques along with include the following: (1) The ecological traditional ecological methods to physiology of birds and mammals assess animal energetics, water balance occupying extreme environments, and thermoregulation, avian biology, particularly desert regions, (2) Animal trophic interactions, and reproductive energetics, including both the physiology effort in small mammals . He works of energy metabolism and heat transfer primarily across the hot deserts of the as well as the use of energy as a vital American Southwest . resource by organisms, (3) The biophysics and physiological consequences of solar heat gain by animals, and (4)The thermoregulatory and energetic significance for animals of habitat and microhabitat selection . In each of these areas, a primary goal is to establish the role of relevant physiological mechanisms in determining the success of animals in nature . Consequently, our research integrates laboratory and field approaches, and subsumes behavioral, biophysical, and physiological techniques .

7 conference organizers

Christofer Bang received his Cand . Scient . Bethany Cutts received her B .A . in degree at the Agricultural University of Environmental Biology from Colgate Norway, and is currently a doctoral student University and is currently a PhD student in Prof . Stan Faeth’s lab . He is interested working with Dr . Ann Kinzig . Bethany is in the effects of urbanization on trophic interested in issues of public education, dynamics, and uses a common desert water use and policy, and environmental plant, Encelia farinosa, and its arthropod justice in the Phoenix metropolitan area . communities as his study system . Christofer She studies these issues through analysis uses mathematical models to get a theoretical of spatially explicit patterns of water-use, understanding, and manipulates number conservation education, and socioeconomic of trophic levels, environmental stress variables in the Phoenix area . and limiting resources in field experiments to elucidate the underlying processes Elizabeth Hagen received her B .A . in and mechanisms behind trophic dynamics . biology from Wittenberg University and her M .S . in stream ecology from Brad Butterfield received his B .A . in biology Virginia Tech . She is currently a doctoral from Rice University and is currently a candidate at ASU working with Dr . John doctoral candidate in plant biology at Sabo . Beth’s dissertation reach focus is ASU in Dr . John Briggs’ lab . He is interested on how temporal and spatial variability in in community, landscape, and phylogenetic aquatic resource availability and structural ecology . Brad uses functional trait screening characteristics of aquatic-terrestrial and analysis of a 75yr . dataset of perennial boundaries influence terrestrial consumer plant community dynamics to understand distributions along desert rivers . coexistence mechanisms and controls on vegetation change in hot deserts .

8 Melissa Kruse received her B .A . in as a direct resource influencing trophic Anthropology and Environmental Studies interactions between streamside crickets from the University of Nebraska-Lincoln . and spiders . She is currently pursuing a PhD in Anthropology in the School of Human Hoski Schaafsma received his B .A . in Evolution and Social Change at Liberal Arts from St . John’s College and ASU under Dr . Katherine Spielmann . is currently a PhD student in Plant Biology Her research is focused on how working with Dr . John Briggs . Hoski is prehistoric peoples of the North American investigating the legacies on modern Southwest dealt with risk and uncertainty landscapes created by human activities, associated with small scale farming in with a focus on anthropogenic landscapes arid regions . Her dissertation takes and patches originally created hundreds an interdisciplinary approach towards and thousands of years ago . His primary understanding how farming communities study sites are in the Sonoran Desert of maintain resilience when faced with central Arizona . changing climatic conditions . Zach Stahlschmidt received his B .S . Kevin McCluney received his BS in with honors in animal sciences from the Biology in 2003 from Florida State . He University of Illinois at Champaign- is now in his 5th year at Arizona State, Urbana . He is now in his third year in working towards a PhD under Dr . John a doctoral program at Arizona State Sabo . In general, his research examines University under Dr . Dale DeNardo . how variation in water availability Although broadly interested in the dynamics influences terrestrial animal communities . of the animal-environment interface, his Most recently he has focused on water dissertation focuses on the regulation of python egg-brooding behavior and its impact on offspring .

photo credit: Christian Mehlführer 9 speaker

abstracts alphabetically by first author

Evolution of social and institutional consequences on the vulnerability of resp onses to resource uncertainty individual farmers and the resilience of in dry regions of India the underlying agro-ecosystem . Rimjhim Aggarwal . School of Sustainability, Arizona State University, Tempe, Arizona Niche construction and food production 85287, USA strategies in arid environments John M . Anderies and Matthew Peeples . This objective of this paper is to elucidate School of Human Evolution and Social the multiple mechanisms through which Change, School of Sustainability, Arizona farmers in dry regions of India traditionally State University, Tempe, Arizona 85287, USA coped with resource uncertainty, how these mechanisms were affected by the Humans occupying what has become the technological changes ushered in the early present-day US southwest in the prehistoric 1970s with the spread of Green Revolution, past were faced with the challenge of living and how the new risks posed by increasing in a harsh, arid environment Land-use. stress on ecosystem services and greater strategies are linked toenvironmental integration of markets in recent years is contexts, and likely more tightly so when affecting the resilience of the agroecosystem . such contexts are highly constraining Because most of the precipitation in the dry such as in the southwest . However, niche regions of India is confined to the monsoon construction theory suggests that months, the crop growing period is very characterizations of changes in land-use short . Any aberrations in the amount and strategies need to explicitly consider not distribution of rainfall can have serious only how humans respond to changing consequencesof livelihoods of farmers, environments, but also how land-use particularly those without irrigation . practices may create the kinds of fundamental modifications in environmental structure In the paper we examine alternative risk that prompt further changes . Using insights coping mechanisms at individual, community, from niche construction theory, we develop and regional levels and their impacts a stylized bioeconomic model of resource across different spatial and temporal scales . use focused on the transition from foraging An important contribution of the paper and limited agricultural production to is to show how the Green Revolution extensive upland shifting cultivation across technologies and the policy changes that large portions of the Colorado Plateau . We accompanied their spread, shifted the argue that the dynamic relationship between burden of risk bearing from the community resource use and adaptation described in to the individual level with important the niche construction framework is an

10 photo credit: Hans Hillewaert

essential aspect of this subsistence change (lichens with green algal phycobionts) in and reflect on the importance of a highly both places appeared related to precipitation variable, arid environment in precipitating patterns . Extended drought was likely this change . responsible for a large decline of all species . Loss of lichen and moss cover is expected Lichens in deserts are dynamics to affect many aspects of this ecosystem . Of Jayne Belnap . US Geological Survey, special concern is the loss of Collema, as it 2290 S West Resource Blvd . Moab, Utah is the dominant source of nitrogen for 84532, USA this region .

Biological soil crusts are an essential part of A primer on spatiotemporal patterns desert ecosystems throughout the world, of climate variability and change in the as they are important in soil stabilization western U.S. and soil fertility . Despite their importance, Julio L . Betancourt . US Geological Survey, there have been few efforts to examine 1955 E . 6th Street Tucson, Arizona 85719, USA the population dynamics of the dominant species comprising these crusts or the effect Two important sources of resource of exotic plant invasions on these dynamics uncertainty in the western U .S . are or how likely future temperature increases decadal-to-multidecadal (D2M) natural will affect them . We followed changes in climate variability and anthropogenic lichen and moss cover for eight years on climate change . D2M variability is the Colorado Plateau and for four years in characteristic of the instrumental record the Mojave Desert . Our data show that cover of the past century, as well as tree-ring of both lichens and mosses can increase chronologies of last two millennia . D2M dramatically over short time periods, often variability can synchronize fluctuations in going from just above 0% cover to as high resource availability within and across as 9% cover in only six months . Cover of regions, and may play a major role in the nitrogen-fixing lichen Collema on the resetting ecosystems at regional scales . Colorado Plateau declined throughout the Although the tropical Pacific is paramount, study, going from 19% in 1996 to as low D2M variability in the North Atlantic (the as 2% in 2003, likely in response to an so-called Atlantic Multidecadal Oscillation increase in monthly maximum temperatures or AMO) and the North Pacific (Pacific during the study period . In contrast, in Decadal Oscillation) also may play the Mojave Desert, Collema and the important roles . Resource managers have moss Syntrichia caninervis responded to barely addressed the challenges posed by precipitation . Changes in chlorolichen cover D2M variability, which makes it that much

11 Effect of precipitation patterns and consumers on grassland and shrubland dynamics in the Northern Chihuahuan Desert . Scott L Collins, William Pockman, Jennifer Johnson, Selene Baez, Eric Small, David Lightfoot . Department of Biology, University of New Mexico, Albuquerque, New Mexico 87131, USA

Consumers, climate variability, and soil resources are all known to impact aridland plant communities, yet the relative importance of bottom up and top down forces varies among aridland ecosystems . In addition, consumer and resource effects are often occurring within a dynamic landscape in

which native C4 grassland is being invaded

and dominated by native C3 shrubs . We present data from long-term field experiments at the Sevilleta LTER in central New Mexico USA to determine the relative impacts of resources (bottom-up drivers) and consumers harder to reckon the impacts of climate on plant community structure and function change . Abrupt cool season warming in the northern Chihuahuan Desert . Using beginning 1976-1984, depending on the exclosures to eliminate all small mammals region, brought on a marked increase in from grass- and shrub-dominated plots for springtime temperatures, an earlier onset over 10 years, we found the plant community of spring by 8 to 10 days, a rise in the structure and dynamics were similar inside elevation at which it rains rather than and outside exclosures . Thus, small mammal snows, a decrease in snowpack, earlier consumers have thus far had little top-down snowmelt timing, a shift to an earlier impact on these aridland plant communities . Instead, plant community dynamics is strongly pulse of snowmelt-fed discharge, and an driven by seasonal and interannual increase in the frequency of large fires A precipitation variability .In general, winter set of nested and downscaled climatological rains affect the composition and diversity and hydrological models was used recently of spring annuals, and summer rains strongly to attribute many of these changes to impact summer composition and aboveground the buildup in greenhouse gas emissions, net primary production . Nitrogen fertilization, but questions remain . My presentation on the other hand, only impacted plant will rely on statistical approaches to identify community dynamics in years of extraordinary spatiotemporal patterns of temperature rainfall . In sum, the evidence to date and precipitation variations in both the past demonstrates that bottom-up forces drive and present to explore their associations plant community dynamics in this aridland with various modes of large-scale climate ecosystem, and that soil resources, such variability in the context of climate change . as nitrogen, also limit aboveground net primary production but only under conditions of consistently high soil water content .

12 Environmental risk and human behavior in is both temporally and spatially limited, southwestern prehistory: A view from the and thus poses an additional challenge Sonoran Desert. to living in the Sonoran Desert . We have Douglas B . Craig . Northland Research Inc ., conducted both field and laboratory studies 32068 Grand Valley Drive, Marana, Arizona to demonstrate that Gila monster have 85658, USA developed both physiological and behavioral responses to deal with variable resource Risk-based models of human behavior have availability . Additionally, we have used become increasingly popular in archaeology manipulative experiments to uncover in recent years . The U S. . Southwest has interactions among these responses and figured prominently in these modeling efforts, attempt to understand the underlying partly because the harsh environment poses mechanisms that drive responses to obvious risks to human survival, and partly anthropogenic disturbances . because high-resolution archaeological and paleoenvironmental data are available for the region . My paper will review some of the important lessons learned from recent studies of prehistoric risk management in the Sonoran Desert . The relative importance of risk-adverse and risk-seeking strategies will be discussed in relation to: 1) the transition from foraging to farming economies, 2) the long-term persistence of prehistoric farming communities throughout the region, and 3) the abandonment of many of these communities shortly before European contact

Physiological and behavioral responses to varying environmental constraints in the Gila monster, Heloderma suspectum. Dale DeNardo, Jon Davis, Carolyn Christel . School of Life Sciences, Arizona State University, Tempe, Arizona 85287, USA

Meeting hydric and energetic needs is critical for the persistence of all organisms and can be especially challenging in arid environments . The Gila monster, Heloderma suspectum, survives in the climatically and therefore resource variable Sonoran Desert and does so by specializing on a unique diet – the contents of vertebrate nests . Such a diet

photo credit: Charles Kazilek Soil foraging animals re-couple critical resource-rich patches across the landscape . resources in dysfunctional woodlands. In the semi-arid woodlands of eastern David J . Eldridge, Alex I . James and Alan Australia, water and nutrients are strong B .C . Kwok . School of Biological, Earth and drivers of primary production, but more than Environmental Sciences, University of a century of overgrazing has disrupted NSW, Sydney 2052, Australia their normal pattern of redistribution from bare source areas to vegetation sinks, Empirical evidence and theoretical predictions compromising feedback processes that suggest that stability and productivity in arid ensure the persistence of smaller-scale systems are greatest where resources are patches . With a relaxation of grazing distributed patchily in the landscape . Temporal pressure, the foraging pits of existing and spatial shifts in geomorphic interconnections and reintroduced semi-fossorial animals such as runoff and sediment processes may have a role in reinstating some of this between patches alters the effects of these small-scale, resource-rich patchiness over

14 extensive areas of woodland . Data control via aerial spraying may be politically collected over the past five years suggest infeasible closer to urban areas . Determining that animal-induced disturbance of surface an optimal control path may prove prohibitively soils has a dramatic effect on soil and costly to determine and implement on an ecological processes by moderating infiltration, agency-by-agency basis . Land managers litter and seed capture, and decomposition need simpler, heuristic solutions that ideally processes . These processes affect soil can be further simplified to “rules of thumb” nutrient pools, plant germination and or “treatment thresholds” such those used productivity, with effects ultimately scaling in integrated pest management . up to higher levels of organization, including feedback effects on the animals themselves . Drivers and consequences of We hypothesize that foraging pits provide interannual variability in nitrogen transport and retention in aridland a spatial and temporal connectivity between stream riparian ecosystems. critical resources, effectively ‘re-coupling’ Nancy B . Grimm . School of Life Sciences, resources in space (and time) . The result is Arizona State University, Tempe, AZ, USA a multi-scaled network of nutrient- and water-enriched patches with a reinforcing The arid and semi-arid southwestern USA and self-regulating effect on the maintenance exhibits strong interannual variability in of heterogeneity in these semi-arid environments . climate, evidence of directional climate Dynamic site selection for invasive change, and rates of urbanization that are species control with dynamic budgets among the highest in North America . Climatic and jurisdictional fragmentation variability produces a variable hydrologic George Frisvold . Department of Agricultural (disturbance) regime, which has consequences and Resource Economics, University of for delivery of nitrogen (N) from terrestrial Arizona, Tucson, Arizona 85721, USA to aquatic components of landscapes and continued transport to downstream, Using buffelgrass (Pennisetum cilare) in recipient systems . Both extreme events Southern Arizona as a case study, this and multi-year drought /wet phases presentation considers the problem of modulate N dynamics through effects on allocating resources to invasive species mobility of terrestrial sources, channel control across space and time . Land geomorphic structure, riparian structure and managers must select control sites processes, and in-stream processes . sequentially because of annual budget Differences in N delivery among years result constraints and because the effectiveness in variations in stream algal cover and of different treatment options and availability relative abundance of Cyanobacteria, showing of labor varies by season . The complexity that the degree of N limitation at a given of this dynamic problem is increased by the time may be a function of previous episodic fragmentation of decision-making among terrestrial–aquatic connections . Because N various public and private agents . The limits production of vascular plants as well presentation examines the size of potential as algae, interannual variability in N delivery gains from interagency cooperation . Spatial to streams potentially influences the differences in control costs also imply trade-offs establishment and/or maintenance of in choice of control methods . While manual ciénegas, an alternative stable state in control becomes prohibitively costly at higher desert stream ecosystems . Other stressors altitudes and greater distance from roads, of arid streams include urbanization,

15 introduction of non-native species, and plant production of floral nectar and fruit increased water withdrawals . Across the resources that mediate interactions with broad southwestern region, these stressors pollinators and seed dispersers; the supply already are affecting stream ecosystem of nutrients (e .g . phosphorus and nitrogen) dynamics to a greater extent than is the by mycorrhizae to plants in exchange for changing climate; however, the interaction carbohydrates; and extrafloral nectar of climate change with anthropogenic resources of plants that attract and reward stressors is likely to increase and ants for their defense against herbivores . produce unanticipated changes in these In arid regions of the world with often important ecosystems . depauperate and uncertain resource environments, such consumer-resource Environmental resource variability favors interactions may be particularly key in shaping complex adaptive traits that mediate the ecology and evolution of species . Here, consumer-resource mutualisms I show how fruit abortion resulting from J . Nathaniel Holland . Department of Ecology excess flower production and environmental and Evolutionary Biology, Rice University, resource limitation may be a complex Houston, Texas 77005, USA adaptive trait of senita cacti that maximizes plant fitness by mediating interactions with Nearly all mutualisms in nature are inherently pollinating fruit-consuming senita moths mediated by the production of resources by in the Sonoran Desert of North America . one species that attract and reward the Empirical and theoretical analyses indicate mutualistic consumers with which it that variation in both extrinsic environmental interacts . Some common examples include resources and intrinsic consumer-resource

16 interactions can be critical to the ecological that feeds back with state . Risk management and evolutionary stability of senita cactus is further complicated by the effectiveness and senita moth interactions . of vigilance as determined by sight lines and even flea burden . At the same time, Foraging games on a pulsed resource: predators manage fear, but must consider Species interactions between competing risk of injury . The foraging game spans three gerbils and their predators trophic levels and joins two species of Burt P . Kotler and Joel S . Brown . co-adapted gerbils with their predators in Ben-Gurion University of the Negev, Mitrani a choreographed game of risk and fear . Department of Desert Ecology, Blaistein Institutes for Desert Research, Midreshet From Atacama to Patagonia- late Ben-Gurion 84990 Israel quaternary environmental change along South America’s “arid diagonal” Sand-dwelling gerbils of Israel compete Claudio Latorre . CASEB-Departamento de strongly for seeds . Seeds are produced Ecologia, Pontificia Universidad Catolica once a year in the spring, but are de Chile and Institute of Ecology and redistributed daily by the wind . The daily Biodiversity, Santiago, Chile pulses of available seeds turn uncertainly into a niche axis . Tradeoffs of harvest A multitude of interconnected arid ecosystems speed, anti-predator ability, and interference straddle the central and southern Andes of ability versus foraging efficiency couple South America from Peru and northern Chile with this to create a mechanism of down to southern Argentina . With origins coexistence based on temporal partitioning . dating back to the beginning of the Andean Gerbils also interact with foxes and owls orogeny, these ecosystems possess both and manage risk using time allocation and unique and endemic floras and share many vigilance . Meanwhile, predators manage genera and species . A large array of fear using time allocation and daring . In this paleoclimate archives indicate that past foraging game, the value of gerbil foraging climate change along this “Arid Diagonal” decisions depend on predator behavior, has been dominated by shifts in South and vice versa . Gerbils employ a monthly America’s major wind belts, the tropical (lunar) cycle of time allocation and vigilance Easterlies and southern Westerlies . Yet, very

17 photo credit: Fish Game & Wildlife Services little is known regarding the late Quaternary interest is not surprising, given the importance dynamics of these ecosystems owing to of this issue to accurately predict global difficulties in obtaining paleoecological change impacts on communities and information from these arid regions that ecosystems, and to understand the conditions include poor pollen preservation potential under which biotic interactions restrict or and low taxonomic resolution as well as enhance biodiversity . Current conceptual chronological uncertainties . Here, I present models predict that the relative importance the results of several different studies using of facilitation and competition will vary rodent middens and other records of biotic inversely across abiotic stress gradients, change from northern Chile . These results with facilitation being dominant under have shed new light on: 1) the timing of stressful conditions . Testing of these models past rainfall increases and vegetation change is often hampered by the experimental in the central and southern Atacama Desert design of the majority of past studies, which before, during and since the Last Glacial have simplified the complexity of natural Maximum; 2) latest Pleistocene groundwater communities by evaluating the interaction and perennial stream discharge in the northern between a single or a few pairs of species, Atacama Desert; and 3) late Quaternary and have not considered how abiotic stress histories of coastal fog ecosystems and promoted by different, but co-occurring, 4) human settlement patterns . We are also resources may affect shifts between now in the process of using similar innovative competition and facilitation . Using examples techniques to understand past environmental from our research, conducted with different change in southern Argentine Patagonia . biotic communities (vascular plants and biological soil crusts) and organization Biotic interactions at multiple spatial levels (species and communities) in semi- scales: their role in maintaining arid ecosystems of Spain, in this talk I ecosystem structure along complex explore how biotic interactions change resource gradients across complex gradients driven by water Fernando T . Maestre, Santiago Soliveres, and nutrient availability, and discuss their Cristina Escolar, Pablo García-Palacios, importance as a driver of ecosystem Andrea P . Castillo, Isabel Martínez & Adrián structure in unpredictable environments . Escudero . Universidad Rey Juan Carlos, The implications of our results for developing Área de Biodiversidad y Conservación, new theoretical, experimental and modelling Escuela Superior de Ciencias Experimentales approaches are also discussed . y Tecnología, C/ Tulipán s/n, Móstoles, 28933, Spain The impact of dominant plant species on juvenile success in The study of biotic interactions and their a desert shrub community implications for ecosystem structure, Maria Miriti . Ohio State University, functioning and dynamics has been a core Columbus, Ohio 43210, USA ecological research theme for decades . Among the ample range of topics covered Resource availability and biotic interactions by this research, the analysis of the have long been linked in plant community spatio-temporal variation of facilitative and ecology and arid plant communities competitive interactions along environmental haveserved as model systems to refine gradients has occupied a prevalent place, understanding of this relationship . Plant especially during the last fifteen years . This spatial distributions reflect heterogeneity of

18 19 limiting resources or the degree of competitive structuring within plant communities . Therefore, analyses of spatial associations within and between species can provide great insight into the relative importance of the biotic and abiotic factors that structure communities . Ongoing monitoring of desert perennials within Joshua Tree National Park has shown two species, Ambrosia dumosa and Tetracoccus hallii, to be codominant as determined by their relative abundance and ubiquitous distributions . Spatial analyses show that these species present distinct spatial distributions . Further, significant positive spatial associations of perennial juveniles with Ambrosia but not Tetracoccus suggest that these species differ in their ability to facilitate conspecific or heterospecific juveniles . I present results from analyses of juvenile recruitment, growth and survival in clusters associated with high and low densities of Ambrosia and Tetracoccus to determine the extent to which positive associations with Ambrosia are the result of enhanced performance or limited dispersal . Although high nitrate levels are found under Ambrosia canopies and high levels of ammonium are found under Tetracoccus canopies, experiments suggest that soil nutrients are not the driving factor determining early plant success . Results are interpreted in light of recent spatiotemporal shifts in the distribution of perennials within this plant community caused by extensive regional drought .

20 Assessing cultural-behavior as well I show how the optimal level of control as biological-genetic adaptations to reflects not only the population dynamics of deserts: Avoiding the pitfalls of the introduced species and others in the host adaptationist syndrome system, but also the relative value of ‘native’ Gary Paul Nabhan . University of Arizona, and ‘invasive’ species . Tucson AZ 85721USA Effects of changes in soil warming, Gould and Lewontin famously critiqued precipitation and elevated CO2 on soil Wilson’s adaptationist program in their widely- carbon dynamics in two arid ecosystems: cited Spandrels of San Marcos essay, but Knows, unknowns, interactions, ecologists, anthropologists and sociobiologists surprises, and uncertainties remain susceptible to the pitfalls outlined in James Reynolds, Weijun Shen’ Paul R . their critique, especially when they propose Kemp, Stanley D . Smith, and Mark Bradford . agendas for dealing with climate change . I Division of Environmental Science and propose that we more critically look at the Policy, Nicholas School of the Environment, term “desert adaptation” to keep policy-makers Duke University, Durham, NC 27708-0328 from building a house of cards on just so Terrestrial ecosystems often exhibit stories from classical natural history and nonlinear and discontinuous responses ethnography . What is missing is the lens of to environmental forcings, e g. ,. climate and political ecology to challenge the assumption disturbance, even if the forcings themselves that the name of the game is “adaptive are continuous and gradual . We give responses” of organisms, and cultures, to examples from two semiarid ecosystems, a dynamic desert . Instead, we need to face the Jornada Basin in southern New Mexico the driving forces and ultimate causes of and the Nevada Test Site of the Mojave change rather than dealing with proximate Desert . Each system is experiencing climate causes and symptoms . change, invasion of exotic species, and Biological invasions in desert systems: elevated CO2 but with local differences . The control problem Using PALS-FT (the Patch Arid Lands Charles Perrings . Professor of Environmental Simulator-Functional Types version), Economics at the Global Institute for we conducted a number of 100-y simulations Sustainability, School of Life Sciences, Arizona to examine the responses to i) step vs . State University, Tempe, AZ, 85282, USA gradual soil warming, ii) changes in precipitation (amount, intensity, seasonality) Biological invasions result in significant and iii) elevated CO2 . Here, we focus only costs in terms of forgone output, control on soil organic matter (SOM) and nutrient costs or environmental damage in every dynamics . Our results suggest that relatively major ecosystem . Desert systems are no large changes in plant FT composition exception . In the Sonoran Desert, for leads to only smallchanges in SOM content; example, it has been estimated that some on the other hand, small differences in soil 380 introduced species currently occupy up structure/texture and decade-long droughts to 60% of the desert . This paper considers can have substantial effects . Significant the problem of how much effort to commit nonlinear interactions were observed: to the control of species that have been increased precipitation and CO2 strongly introduced and have either established or counteracted each other while soil warming have at least the potential to establish . amplified their combined effects on both

21 SOM and nutrient dynamics . In general, the and for precipitation change to play an combinatory effects were non-additive and extremely important role in the community

actually less than the sum of the corresponding dynamics of a higher CO2 world . single-factor effects . Nitrogen and substrate supply were two key processes governing Mitigating agricultural risk in the strength of interactions . Finally, we arid environments conclude that desert soils have the potential Katherine Spielmann, Margaret Nelson, to serve as significant carbon sinks if future Scott Ingram, and Matthew Peeples . School dryland environments become wetter, warmer, of Human Evolution and Social Change, and enriched with CO2 . However, crucial Arizona State University, Tempe, Arizona unknowns underscore the uncertainties of 85287, USA potential factors influencing soil carbon In this presentation we discuss the dynamics in arid ecosystems . relationships between risks of resource Effects of elevated CO2 and precipitation shortfall under agricultural production, and change on production processes in the strategies farmers used to mitigate those Mojave Desert risks . The strategies we consider are Stanley D . Smith . University of Nevada, Las storage, exchange, and migration . We Vegas, Nevada 89154-1087, USA evaluate the utility of these strategies to mitigate the risk of resource shortfall under A conceptual analysis by the TERACC conditions of marked variation in access (terrestrial ecosystem responses to climate to water for crop production, to which change) group suggests that rainfall will prehistoric farmers in the US Southwest increase in variability, with larger single events had to adapt . We also discuss the relationship interspersed with longer drought intervals, between the temporal and spatial scales with future climate change . Such a change of variation in access to water, and the in pattern may have positive benefits for success of particular strategies . Our production in xeric versus more mesic discussion is illustrated with data from

ecosystems . Elevated CO2 is well known conceptual models and two archaeological to stimulate plant production in desert case studies from the Mimbres and Salinas systems, but changes in rainfall amount regions of the US Southwest . At the local and patterns may significantly change the scale, household-based, multi-year storage interaction between those two drivers . and community-scale restricted sharing of Examination of the 10- year record of plant stored food appear to have been effective production at the Mojave Desert Free-air primary strategies for mitigating inter-annual CO2 Enrichment (FACE) site shows variation in precipitation and stream flow . that almost all production gains occurred The more enduring risk of resource shortfall in above-average wet years, with few under relatively high population levels and enhancements in dry years . Drought-Wet long-term drought, however, was addressed cycles also had almost opposite effects on primarily through permanent emigration from the CO2 response of native and exotic affected areas . At the scale of the Southwest annuals . Therefore, if southwestern climates region, migration was a resilient strategy get drier and/or more variable with global for farmers to cope with intense drought warming, we anticipate the highly episodic conditions . On those rare occasions production patterns of deserts to potentially when the water supply was assured, become even more episodic in the future, the Salinas case being one of these,

22 subsistence farming in the Southwest was uncover community processes that favor a highly robust practice, and populations species coexistence and discern the remained in place until the disruption of responsible underlying functional traits . Spanish colonization . Finally I will show how the warming and drying of the Sonoran Desert over the Species diversity maintenance and last 25 years has led to a shift in species long-term change in a community of composition, paradoxically favoring Sonoran Desert annual plants species that germinate and grow best D . Lawrence Venable . Department of in cold temperatures . Ecology & Evolutionary Biology, University of Arizona, Tucson, AZ 85721 Desert rodents: Some dogmas re-visited Glenn E . Walsberg . School of Life Sciences, A special property of desert annuals that Arizona State University, Tempe, Arizona appeals to plant ecologists is that they have 85287, USA fast population dynamics . This means they make a good system for studying plant Because of their persistent high temperatures population and community dynamic processes . and absence of water, subtropical It also means that they act as a bit of canary deserts arguably represent the terrestrial in the mine for understanding vegetation environment that offers the greatest dynamics in changing environments . I will physiological challenges for organisms . describe a 25-year data set on the One of the most conspicuously successful demography of a community of Sonoran groups of animals in such habitats is small Desert winter annuals . We have used it to rodents . Despite the extensive attention

23 photo credit: Petrified Forest National Park/Park Ranger that has been placed on them for more presented, and reveal an animal routinely than 60 years, however, material found in exposed to high environmental temperatures textbooks and review articles contain and which critically depends upon succulent generalizations that can be quite misleading . food as a water source . Such examples I will present two examples . One is the provide cautionary notes to biologists role of hyperthermia and behavioral as both producers and consumers of thermoregulation in ground squirrels . In scientific information . this case, the description presented to Pulsed resources and hot deserts- the generations of students and which remains importance of columnar cacti to entrenched in the literature is revealed consumer populations to be simply a speculation that was not Blair O . Wolf and Andrew Mckechnie . Biology confirmed by subsequent empirical data . The Department, University of New Mexico, second example is that of kangaroo rats as Albuquerque, NM 87131-0001, USA the prototypical desert rodent that avoids high temperatures and survives on a diet In the Sonoran Desert of Arizona, saguaro, of dry seeds without access to free water Carnegiea gigantea and organ pipe cacti, or succulent food . Subsequent studies have Stenocereus Thurberi, provide extensive revealed this generalization to be most likely water and energy resources to the consumer valid only in the least interesting conditions: community during the hottest and driest winter or relatively cool deserts . Data for periods of the annual cycle . Between May kangaroo rats living in hot deserts paint a and August, columnar cacti release a huge considerably different portrait than commonly pulse of nutrients into the ecosystem in the

24 photo credit: Tuxyso

form of floral nectar and fruit pulp . Cacti are represents approximately 43% of the bird unusual among arid zone plants because community’s carbon intake . The saguaro they offer an abundance of succulent, resource penetrates deeply into both energy rich fruit to consumers in an insectivorous and granivorous bird environment where water and nutrient populations where it provides water, abundance may constrain animal function . energy and nutrients . In contrast, these Quantifying the importance of these resources have very limited penetration into resources to consumers provides important other consumer groups . In small mammals, insight into the role that cacti play in for example, cacti resources comprise less structuring animal communities . This than 10% of the carbon intake of the rodent nutrient pulse can be tracked into consumers community during the same period . by means of its stable isotope signal, which differentiates cacti from other plant resources in the environment . Plants such as saguaro use CAM photosynthesis and have tissue carbon isotope ratios that differ strongly from the isotopic values of the majority of desert plant species, which use C3 photosynthesis .

During June, the peak period of fruit production, stable isotope analysis of avian plasma indicates that saguaro fruit

25 poster abstracts

Variation in community structure Climate change and its impact on and diversity: A decade of arthropod Nepalese agriculture. monitoring in urban areas. Govinda Bhandari . Director National 1 2 Christofer Bang and Stanley H . Faeth . Institute of Natural Sciences, Dillibazar, 1 Arizona State University, Tempe, Arizona Kathmandu, Nepal, G . P . O . No . 7589 2 85287, USA, The University of North EPC . 5546 Carolina at Greensboro .

Exponential growth of CO2 and other Two widely held notions about urbanization greenhouse gasses in the atmosphere is are: 1) diversity decreases in urban areas causing climate change . It affect agriculture, and 2) remnant or restored habitats will forestry, human health, biodiversity, snow have or re-gain the same diversity as cover and aquatic to mountain ecosystems . natural areas . More recent research has Changes in climatic factors like temperature, shown contradicting results for both ideas . solar radiation and precipitation have We monitored arthropod communities with potentials to influence crop production . pitfall traps in the Central Arizona Phoenix Despite many efforts possible on combating (CAP) area over ten years in desert sites, impacts of climate change, there are still desert remnant sites and in two common difficulties in Nepalese agriculture . With an landscaping categories: xeric and mesic average of 0 06ºC/year,. a rise in temperature yards . We also compared these data with from 1975 to 2006 by 1 .8ºC has been two years of sweep net samples . We found recorded in the country . Problem of frequent that diversity in remnant areas declined drought, severe floods, landslides and mixed drastically over this timeframe, that temporal type of effects in agricultural crops have variation in both diversity and abundances been experienced in Nepal because of climate

was considerable in all habitats, and that change . Study done on CO2 enrichment desert and mesic habitats were more technology at Khumaltar revealed that the similar than anticipated . Ground dwelling yield of rice and wheat increased by 26 .6%

arthropods and arthropods associated with and 18 4%. due to double CO2, 17 .1% vegetation responded differently to habitat and 8 .6% due to increase in temperature type . Our results indicate the complexity respectively . A crop simulation model

of urbanization effects superimposed on (DSSAT) to study the effects of CO2, a background of seasonal and regional temperature and rain in NARC showed climatic effects on arthropod diversity over positive effect in yield of rice and wheat in the long term . all regions, but negative effect in maize especially in Terai . In Nepalese agriculture, the time has come for the authorities to

26 find out adaptive measures to mitigate a climatic regime that has resulted in a the effects to reduce untold natural distinctive arid-adapted flora and fauna . calamities and miseries due to recent Such a definition, although still prone erratic weather pattern . to exceptions, satisfies the requirement of including most areas commonly recognized The desertlands of North America. as desertscrub, both in North America and David E . Brown and Elizabeth Makings . throughout the world including the so-called School of Life Sciences, Tempe, Arizona polar deserts of arctic regions . Indeed, 85287, USA desertlands occur in all four climatic zones and in every biogeographic realm if one The term “desert” is widely used to refer recognizes the Andulucian Desert of to any arid, lightly populated landscape, southern Spain as desertland . Rain-shadowed and “going out into the desert” and “desert continental deserts in North America include living” has involved plant communities ranging the cold temperate Great Basin Desert, from open desertscrub through a variety the warmtemperate Mojave and Chihuahuan of grasslands and scrublands, to deserts, and portions of the subtropical open woodlands . More correctly from Sonoran Desert, which also includes the a biogeographic perspective, the desert continent’s only coastal desert communities appellation has been used to describe various within its Vizcaíno and Lower Colorado biotic communities (desertland) or vegetation- River subdivisions . types (e .g ., various types of desertscrub) . As such, numerous definitions have been Effects of clonality on physiological proposed for both, none of which is entirely plasticity in Cylindropuntia satisfactory . Most American biogeographers, (Cactaceae) species . however, accept a description of Mark Buhanan . School of Life Sciences, desertlands as those arid communities Arizona State University, Tempe, Arizona receiving less than 10 to 12 inches of 85287, USA precipitation a year and in which perennial plant cover ranges from nearly zero to Desert environments are characterized by less than 50% of the ground surface . There long periods of stress but also by ephemeral are exceptions, however, such as certain periods of nutrient abundance . The ability edaphically controlled communities within of perennial plants to respond to both biotic communities that are clearly not conditions determines the success of the desertscrub such as the so-called “pumice individual both ecologically and evolutionarily . deserts” of the intermountain West . We Physiological plasticity is expected to be a therefore further define desertlands as having mechanism whereby growth limited plants

27 may respond to ephemeral environmental of the roots shortly after the treatment fluctuations . Cylindropuntia (family Cactaceae) period to demonstrate the presence and is adapted to this stressful but variable magnitude of plasticity in an important environment and is expected to exhibit physiological parameter (nutrient uptake) . physiological plasticity as a response to Population genetic variation was estimated that variability . Cylindropuntia species range using RAPD’s (randomly amplified polymorphic in extent of clonality . Vegetative propagation DNA) to better understand how plasticity allows establishment of propagules in less might work in natural populations the role favorable microsites which may be too of plasticity in natural populations . severe for seedling establishment and the environments experienced by the propagules Nitrogen availability and population are different . This research seeks to examine density: Effects on a migratory polyphenic grasshopper. physiological plasticity as a response to Arianne Cease1, Shuguang Hao2, James variable nutrient levels and to compare Elser1, Le Kang2, Jon Harrison1 . 1School of the magnitude of plasticity across species Life Sciences, Arizona State University, with different propagation strategies . Since Tempe, Arizona 85287, USA, 2Institute of phenotype is both a function of variation Zoology, Chinese Academy of Sciences due to plasticity and the underlying genetic variation, both will be investigated for the Insects respond to high density in a study species using two complimentary variety of ways that, if exposed during approaches . Clones of several individuals larval development, can culminate in were grown under three nutrient (nitrate drastic changes in physiology and fertilizer) regimes and the nitrogen content morphology . Some of these changes can be beneficial in aiding dispersal from a crowded habitat . For grasshoppers and other insect herbivores that tend to be nitrogen (N) limited, plant quality also affects these characters . We tested this in a dominant pest-grasshopper in the arid grasslands of China’s Xilin River basin region, Odaleus asiaticus . Grasshoppers were assigned to 1 of 4 treatment groups

28 (high or low density and N fertilized or environmental justice framework, we evaluate unfertilized grass) . There was a significant the landscape of opportunity to engage interaction effect between diet and density . with information about water supply and Grasshoppers reared in high density and water quality created by the 42 organizations fed high N diets had a significantly serving metropolitan Phoenix . Contrary to decreased growth rate and adult mass, predictions, percent Latino, renters, and increased development time, increased school-aged children are positively related metabolic rate, and altered morphometric to high water information (WI) availability parameters as compared with the other in our maps . However, preliminary results three treatment groups . These results indicate that the content and framing of suggest that insects reared in high density information may prevent these social groups are more sensitive to changes in dietary N from finding the information compelling or and that the exhibited phenotypic plasticity engaging . This indicates that spatial and could increase their migratory capability . ideological barriers to WI engagement may interact synergistically . This may lead to Chutes or Ladders? Examining the roles lower public awareness about water issues of geography and ideology in mediating than would otherwise be expected given the the relationship between information prolific amount of information provided to providers and the public’s environmental the public . There is some evidence that awareness. the structure of interactions among water Bethany B . Cutts12, Ariana Fox12, Allyn information providers may partially explain Knox13, and Nicholas R . Moore4 . 1Decision the mismatch between information being Center for a Desert City, POB 878209, provided and that desired by the public . Arizona State University, Tempe AZ 85287- 2 8209 School of Life Sciences, POB 874601, Increased territorial responses in urban Arizona State University, Tempe AZ 85287- populations of two Sonoran Desert birds: 3 4601: Barrett Honors College, POB 871612, Hormones or Ecology? Arizona State University, Tempe AZ 85287- H . Bobby Fokidis, Miles Orchinik, and Pierre 4 1612: Department of Geography, Hunter Deviche . School of Life Sciences, Arizona College – CUNY, 695 Park Avenue New York, State University, Tempe, AZ 85281, USA NY 10065 In many birds, the onset of breeding is Public information campaign evaluation marked by territory establishment and its methods often under value the impact subsequent defense from conspecific of information and ignore the larger political intrusion . Territories may be defended for context of the information being provided . various reasons including the monopolization While some studies focus on the impact of of spatially limited resources . These a one information program on one action, resources can vary between habitats, which effort to educate the public can informally in turn may influence territorial behavior . provide legitimacy to community interests We measured the territorial behavior of male and empower political and community Curve-billed Thrashers, Toxostoma curvirostre, action beyond the individual or household and Abert’s Towhees, Pipilo aberti, belonging level . Further, few studies have considered to urban and rural Arizona populations through the potential impact of several programs direct observation of birds in response to administered by several organizations with conspecific song playback recordings . overlapping geographic ranges . Using an Corticosterone (CORT) has been associated

29 with avoidance behavior in some species . Geographic variation in the energetics of In circulation, most CORT in birds is reversibly inactivity: Individual and environmental bound to corticosterone binding globulin influences on the resting metabolism of (CBG) and this interaction presumably Gila monsters. 1 2,3, mediates the amount of free (unbound) C .M . Gienger , Jon R . Davis Dale F . 2 4 hormone available to interact with DeNardo , Daniel D . Beck , and C . Richard 1 1 cellular receptors . We measured total and Tracy . Program in Ecology, Evolution, estimated free plasma CORT concentrations and Conservation Biology and Department in urban and desert thrashers and towhees of Biology, University of Nevada, Reno . 2 and correlated these concentrations to Reno, NV 89557, School of Life Sciences behavioral responses to song playback . and Organismal, Integrative, and Systems We also measured population densities of Biology, Arizona State University, Tempe, 3 the two species in urban and rural areas AZ 85287, Department of Biology, Rhodes as it may influence aggressive interactions College and Memphis Zoo, Memphis, TN 4 between conspecifics . Both urban thrashers 38112, Department of Biological Sciences, and towhees were significantly more Central Washington University, Ellensburg, aggressive than desert conspecifics parts WA 98926 but this difference was not related to total or free plasma CORT or to differences in Variation in rates of energy expenditure of ectotherms can largely be explained by two population density between habitats . These factors, body temperature and body size . results will be discussed in the context of Together these can account for more than the effects of urbanization on behavior and 90% of variation in resting metabolism endocrine physiology . of squamate reptiles (lizards and snakes), and can thus be useful predictors for estimating energetic requirements . But because species are distributed across heterogeneous landscapes, which can encompass a range of both environmental conditions and selective pressures, body size and body temperature may vary among populations . Thus, population differences in the magnitude and distribution of energy use may be expected to differ as a function of differences in size and thermal regimes .

We modeled the effect of individual body size and body temperature on geographic variation in resting metabolism of Gila monsters . Gila monsters are a particularly interesting species to investigate the causes and consequences of variation in resting metabolism, as they are almost always resting . Some populations can spend more than 95% of their time quiescent underground and allocate more than 90% of their annual metabolic expenditure to inactivity .

30 We gathered field data from four ecologically significant inter-and-intra-specific variation distinct populations from the Chihuahuan, in consumer nutrient content, but proposed Mojave and Sonoran Deserts . Environmental mechanisms underlying this variation remain conditions (temperature, precipitation, understudied, especially for terrestrial elevation, etc .) at the different study sites consumers . Therefore, we analyzed natural vary markedly, and they represent nearly variation in nutrient content within and among the entire range of environmental variation consumer species across four desert food experienced by Gila monsters . Both body webs (Atacama Desert, Chile) . Additionally, size and body temperature patterns varied we evaluated the relationship between body between populations, and we show that size and nutrient content in consumers . both individual (body size) and environmental Whole-body elemental composition varied (thermal regimes) effects can influence among taxa . On average phosphorus content temporal and geographic patterns of Gila was more variable than nitrogen content, showing five-fold variation among species, monster metabolism .

Stoichiometry in desert food webs: Assessing inter-and-intra-specific variations in consumers C:N:P ratios. González, A .L 1,4. , Fariña, J M. 1. , Kay, A .D . 2, Pinto, R 3. & Marquet, P .A 1,4. . 1Center for Advanced Studies in Ecology and Biodiversity & Departamento de Ecología, Pontificia Universidad Católica de Chile, Santiago . Chile . 2Department of Biology . University of St . Thomas . St . Paul, Minnesota, U .S .A . 3Universidad Arturo Prat, Iquique . Chile . 4Institute of Ecology and Biodiversity (IEB), Casilla 653, Santiago, Chile .

while N showed a two-fold variation . Ecological Stoichiometry (ES) focuses in Elemental content also showed variation the causes and consequences of variation within taxa and in general, P content was in elemental composition within and among more variable . The N and P content of whole organisms, and links these differences to data set were negatively related to body main ecological processes . Thus, ecological size, but some species showed no relationship interactions can be strongly and reciprocally between nutrient content and body size . influenced by the elemental requirements These results do not support the common of the consumers and those provided by assumption in stoichiometry models that their food . While empirical data shows elemental composition is constant within that autotrophs exhibit a wide variation in consumer species . The high variability on nutrient content, ES predicts that heterotrophs nutrient content of invertebrate and vertebrate maintain a constant intra-specific nutrient consumers from desert food webs, points to content, but a wide variation across the need for further studies across a range taxa . Recent research, however, indicates of terrestrial ecosystems .

31 Geomorphology, hydrology and communities were found on young landforms vegetation along Sonoran Desert with stable unincised channels and frequent ephemeral drainages. higher volume flows . (4) On the youngest Matt Haberkorn . Phoenix College surfaces with active deposition taking Biology Dept . 1202 W . Thomas Rd . place, the largest most frequent flows, Phoenix, AZ 85013 and unincised channels Parkinsonia florida dominated communities . Interconnections between the geomorphology, hydrology, and vegetation patterns of four Dispersal and colonization of Philodina small to midsized Sonoran Desert ephemeral megalotrocha (Rotifera, Bdelloidea) drainages are the focus of a continuing in aquatic habitats in the Chihuahuan study northeast of Phoenix, Arizona . Desert. These ephemeral drainages are complex Lina Hamdan & Elizabeth Walsh . Department associations of geomorphic histories with of Biological Sciences, University of Texas various piedmont landforms, which determine at El Paso, El Paso, Texas 79968-0519, USA channel incision processes and channel morphology . Geomorphic histories result in The Chihuahuan Desert is a unique region typical landscape scale hydrologic patterns with high biodiversity . There is a high degree determining volume and frequency of of local endemism of freshwater biota, but ephemeral flow events along drainage relatively few studies have been focused reaches . Channel order and watershed on zooplankton . Bdelloid rotifers are one area were found to be poor hydrological and component of these ecosystems and often plant community predictors . This indicates dominate very temporary habitats . Bdelloids moisture does not accumulate downstream are usually assumed to be cosmopolitan in the same fashion as perennial streams species due to their potentially high dispersal and moisture alone does not determine rates . Distribution records of the bdelloid plant communities . Rather, landforms and Philodina megalotrocha extend from North associated channel morphology where America to New Zealand . However, relatively found to be strong predictors of hydrology little is known concerning its ecology and and plant communities . Each piedmont genetics . The goals of this study are to: landform has a typical channel morphology 1) determine whether the distribution of and resulting hydrology, resulting in typical P. megalotrocha in the Chihuahuan Desert plant communities . Four geomorphic plant is associated with ecological characteristics community associations have been identified . of habitats and 2) investigate whether (1) The oldest piedmont landforms with P. megalotrocha is a truly a cosmopolitan highly developed soils, typically nearest to species and not a complex of cryptic mountain fronts, contained deeply incised species . Redundancy analysis was applied channels . Ephemeral flow was not observed to investigate relationships between rotifer for the majority of these channels over populations and 23 environmental factors . the two year observation period and plant Variables were added when they provide communities were defined by Parkinsonia extra fit to the model at a significance level microphylla . (2) Downstream on slightly of p<0 .05 . The first 4 conical axes explained younger landforms with less developed 8 6%. of the variance in the species data . soils, Acacia greggii characterizes This analysis indicated that P. megalotrocha wider stable channels with frequent is associated with the Cattail Spring pools ephemeral flows . (3) Prosopis velutina (Big Bend National Park) . Also, it is somewhat

32 associated with flow and the summer attention . Due to its dramatic topographical season . To determine the extent of genetic relief and its location between the Sonoran differentiation among geographically isolated and Chihuahuan Deserts and subtropical populations, cox1 sequences were used and temperate North America many unique to construct distance matrices using and rare species and habitats occur in the the Neighbor Joining algorithm . Genetic region . Sky Island Alliance is a grassroots variation was high among populations organization dedicated to the protection (ranging from 1% to 22%), which indicates and restoration of this rich natural heritage . that P. megalotrocha may be a complex of We bring volunteers, landowners and agency cryptic species . personnel together to plan and implement riparian and upland restoration projects to Restoration in the Sky Islands: bringing protect vital desert, grassland and riparian volunteers, landowners, practitioners and wildlife and habitats . agencies together to benefit wildlife and habitats in a global biodiversity hotspot. Four case studies on restoration projects Trevor Hare, and Sarah Williams . Sky Island are presented that can inform similar Alliance, 738 N Fifth Avenue, Suite 201, projects and plans . First is a study of a Tucson, Arizona 85705, USA funded but flawed restoration planning project in the headwaters of the Santa The Sky Island region of the Southwestern Cruz River where a lack of communication US and Northwestern Mexico is recognized between the project manager, adjacent internationally as a biodiversity hotspot landowners, and land and wildlife managers and is garnering increased conservation doomed its completion . Second is a study

photo credit: Jim Elser

33 Dissolved organic carbon dynamics in Tempe Town Lake. H . Hartnett1,2, J . Shipp2, David Lui2, H . Waterman3 . 1School of Earth and Space Exploration, Box 871404, Arizona State on an un-funded but ongoing restoration University, Tempe AZ 85287-1406, 2Dept . project in the Huachuca Mountains where of Chemistry and Biochemistry, Box 871406, man-made spring and creek impoundments Arizona State University, Tempe AZ 85287- allowed bullfrogs to extirpate native aquatic 1406, 3Dept of Chemical Engineering, Arizona species . Third is a study of a fully funded State University, Tempe AZ 85287 ASU large-scale ciénega restoration project in the Peloncillo Mountains where in 2009 Urban lakes provide a range of ecosystem we hope to restore flood flows across a services to their communities but there 200-acre wetland that is drying due to is little information about the long term man-made diversions . Fourth is a study on biogeochemical behavior of these systems . upland restoration focusing on wildland We have been investigating basic water road density reductions to protect the chemistry and dissolved organic carbon oak savannas and riparian areas of dynamics in Tempe Town Lake, Tempe the Sonoita Valley and Ciénega AZ since Jan 2005 . This man-made lake Creek watershed . provides both recreational and flood-control services . Over this four year period, the lake has experienced two high-flow events (Jan 05 and Feb 08) that “reset” the lake with fresh water from the Verde and Salt Rivers . In between these two events the lake experienced little input of water, except for rainfall events and the regular inputs from recharge wells . There have been four monsoon periods over the time of our study; two years with relatively wet summers (2006, 2008) and two years with relatively dry summers ( 2005, 2007) . The bulk DOC concentrations in the lake are generally highest (> 6 mg C L-1) during the winter high-flow events and can exhibit peak concentrations following summer monsoon storms . During dry periods the major ion chemistry in the lake reflects concentration increases due to evaporation; in contrast, DOC concentrations for the same periods decreases due to biological consumption and/or photochemical oxidation . Results from

34 ESI-MS analysis suggests these periods of woody and herbaceous floodplain each reflect very different DOC compositions vegetation as well as wetland vegetation and thus sources . in the active channel zone . Preliminary results of this correlative analysis will be Resolving human and ecological reported and compared to results of water needs in a changing region: similar studies on other regional rivers . Environmental flows in the Verde watershed, central Arizona. Neuroendocrine control of reproduction 1 1 1 A .F . Hazelton and J .C . Stromberg School in two geographically distinct populations of Life Sciences, Arizona State University, of Cassin’s sparrows, Aimophila cassinii. Tempe, AZ, 85287-4501, USA Laura L . Hurley and Pierre Deviche . School of Life Sciences, Arizona State University, The Verde River is a large, perennial, Tempe, AZ 85287, USA free-flowing river in central Arizona . In the midst of this semi-arid landscape, extensive Seasonally breeding birds use various and diverse aquatic and riparian communities proximate cues to regulate their reproductive depend on the river’s abundant surface cycle . In stable environments (e .g . temperate water and ground water . Human populations zones) the most important primary cue in the region also depend on these same is day length . In demanding environments water resources . The human population in (e .g . deserts) supplementary cues associated the Verde watershed is growing rapidly, with weather (e g. . monsoon rains) may and there is a danger that unchecked play a more significant role . Little is known anthropogenic water use, such as groundwater about how these cues are integrated to pumping and surface water diversions, regulate secretion of the neuropeptide may impact the biotic communities along gonadotropin-releasing hormone (GnRH), the Verde . which controls gonadal activity by stimulating release of anterior pituitary gonadotropins . The environmental flows approach to water This study uses N-methyl-DL-aspartate management attempts to balance ecological (NMA) administration to evaluate GnRH cell water needs with anthropogenic water use . function in two free-living Cassin’s Sparrow The term “environmental flows” refers to populations (Arizona and Colorado) that the water necessary to maintain aquatic employ temporally different breeding and riparian ecosystems . One tool used to strategies . Differences were evaluated determine environmental flows is the flow by measuring changes in plasma testosterone response curve; this is a graph that depicts and luteinizing hormone a change in the abundance of a particular (stimulated by NMA species or community as water availability administration), gonad declines . This correlative approach was size, and neural GnRH taken to quantify the relationship between expression in both water availability and riparian plant populations through community metrics on the Verde River . out the breeding season . Three piezometers were installed at each Initial findings confirm of three study sites and equipped with temporally shifted seasonal pressure transducers to track changes in reproductive patterns, but further ground water depth . Vegetation surveys investigation is needed to understand were conducted and included measurements the control of GnRH release .

35 Soil moisture controls on creosotebush daily images that allows for direct comparison (Larrea tridentata) phenology: When it with eddy flux and micro-meteorological rains it greens and yellows. data sets . In this study we installed three Shirley A . Kurc and Lisa M . Benton . School pheno-cams within the footprint of an eddy of Natural Resources, University of Arizona, covariance tower at a creosotebush- Tucson, AZ, USA dominated ecosystem within the Santa Rita Experimental Range, southeastern Arizona . Ultimately, to predict the holistic effects We illustrate how soil moisture drives green of climate change on natural systems, an up, and therefore carbon uptake, in desert understanding of ecosystem level phenology ecosystems . We also show how temperature as an integrative measure of ecosystem and soil moisture influence flowering in this functioning, is critical . Because creosotebush repeat-blooming shrub . is the most common shrub species of the warm desert ecosystems of North America, Past vegetation and climate changes the green up of these ecosystems largely in the Atacama Desert of northern Chile influence carbon fluxes in these regions . estimated from fossil pollen in rodent Additionally, because creosotebush is a middens. 1 2,3 repeat bloomer, it is a stable resource in Antonio Maldonado , Claudio Latorre , 4 1 an otherwise unpredictable and harsh Julio L . Betancourt . CEAZA, U . Serena, La 2 environment for hundreds of pollinators Serena, Chile, CASEB - Dept . Ecología, P . U . 3 4 that synchronize their emergence with Católica, IEB, Santiago, Chile, US Geol . flowering . As warmer and drier weather Survey, Tucson, Arizona, USA predicted for the southwestern United States, these important phenological Fossil rodent middens are common in small activities are certain to be affected . caves and rock shelters throughout the Atacama Desert of northern Chile . Middens spanning the last 50,000 years BP were collected from Quebrada del Chaco in the southern Atacama Desert (25º30’S; 69º15’W), a key transitional region between the southern Westerlies and tropical Easterlies where the absolute desert reaches its maximum inland penetration . Here, we use pollen preserved in the midden matrix to infer past vegetation and climate changes in this hyperarid region . Middens were collected between 2600 to 3500 m of altitude, among contracted vegetation that Typical phenological datasets are provided persists only along rocky outcrops and from discrete sampling periods (e .g . dry gullies . Distinguishable patches of once per season) . In pulse-driven dryland steppe grassland and high Andean plant ecosystems, these discrete samplings species form only above 3500 m . are often insufficient to really correlate with weather events . In situ time-lapse digital Our results indicate that Fabaceae, cameras (hereafter pheno-cams) have the Chenopodiaceae and Ephedra were advantage of providing a continuous set of dominant around ~50,000 years BP .

36 This shifted towards the Brasicaceae and Holocene, from ~9,000 to 1,400 years BP . Fabaceae ~40,000 years BP at lower altitudes These results agree well with nearby (2700 m) with Asteraceae and Poaceae records of vegetation change as well as dominating at higher elevations (3500 m) . other paleoclimate proxies . Brasicaceae and Asteraceae became dominant Acknowledgements: FONDECYT#1060496 at lower altitudes between ~20,000-10,000 The fate of combustion-derived carbon years BP, whereas highly diverse pollen deposition in urban soil. assemblages dominated by Asteraceae Yevgeniy Marusenko1, Pierre Herckes2, and Poaceae existed at higher altitudes . and Sharon Hall1 .1School of Life Sciences, By ~9,000 years BP, assemblages were 2Department of Chemistry and Biochemistry, dominated exclusively by Chenopodiaceae, PO Box 874501, Arizona State University, which only in the last millennium has been Tempe AZ 85287-4501, USA replaced by Brasicaceae and Fabaceae . By comparing to data from modern local Urbanization has led to an increase of pollen rainfall, we can establish the timing combustion-derived, organic carbon emissions of significant changes in the vegetation, that can deposit diffusely to soils within and with the most prominent change documented surrounding our cities . One of the most by an elevational descent of high elevation common types of urban pollutants, Polycyclic taxa between~20,000-10,000 years BP by Aromatic Hydrocarbons (PAHs), may be about 1000 m . This was followed by a sharp toxic and are detrimental to environmental increase in aridity during most of the quality . Despite this concern, there is a

37 photo credit: Geoff Gallice

38 considerable gap in our knowledge about the health consequences, distribution, or environmental fate of PAHs in highly populated urban areas . Soil microorganisms utilize organic compounds as a resource, and they are known to degrade petroleum-based point source pollution in contaminated soil . However, little is known about their capacity to degrade diffused carbon pollution deposited from the atmosphere . First, we are asking the question, what is the magnitude, distribution, and fate of non-point carbon pollution in an urban area? Also, can urban soil microorganisms metabolize combustion- derived organic compounds in urban soils and are they better adapted degraders compared to microbes away from the city? To accomplish our research goals, we will characterize PAHs and other anthropogenic compounds near roadway soils across the Phoenix valley, explore the abiotic and biotic fate of PAHs in soils, and assess the importance of microbial community structure in PAH dynamics . Preliminary data suggest that PAH concentrations in arid Phoenix soils are nearly an order of magnitude lower than expected based on data from other cities . We are currently exploring if road properties and soil conditions may be correlated with PAH concentrations, and if our soils have unique microbes that have the ability to degrade these compounds .

Eco-systemic restoration: A model community at Salton Sea. Ilaria Mazzoleni, P . Ra, A . Barthakur, S . Price, V .Zajfen, S . Varma, B . Mehlomakulu, H . Portillo, S . Milner, S . Proudian . Southern California Institute of Architecture, Los Angeles, CA, USA

The traditional model of growth is a ‘zero sum’ game with discrete land use typologies, where growth in one can only happen at the expense of another . Our primary motivation in developing a systemic community in a

39 desert environment is to provide a paradigm essentially a basin that had filled up with shift in accommodating growth – by capturing occasional flooding of the Colorado River, and integrating systems that are cyclical but now gets constantly replenished by the in nature and time, with each cycle agricultural runoff from the area surrounding rejuvenating and healing the surrounding it . The lack of any outlets makes it a very ecology rather than eroding it over time . unstable ecosystem with rising salinity and The approach is holistic, in that we consider increasing toxicity . The process of healing interrelationships between all processes is emphasized by a symbiotic relationship fundamental to sustaining life and preserving between the designed community and the nature – water and energy cycles, agriculture natural environment in and around Salton and seasonality, production and the Sea . Key objectives in this is to reduce the exchange economy, as well as social needs Sea’s salinity levels, provide alternative of a multi-generational community . Our models of agriculture, and maintain the strategy, however, is hinged on the notion ecosystem it supports . We have incorporated of restoring scarred landscapes, making a number of strategies that emphasize this them givers of life, and enhancing their symbiotic relationship . Nature sensitive integration into the surrounding ecology agricultural practices and crop types provide and life . Our project site is located on the a food source and economic benefits to the northern bank of the Salton Sea, Ca . It is community while eliminating chemical runoffs

40 into the Sea . Passive energy strategies such microbial biomass and abundance . Following as the heat sink and solar ponds use the Sea’s experimental wetting, carbon dioxide (CO2) mass and salinity to the advantage of the flux from interspace soils was positively community . The goal is to create a community correlated with N deposition, whereas in in the desert that does have a net 0 impact plant islands, soil CO2 flux was positively on emission, waste, energy and water while correlated with soil moisture content and reducing the Sea salinity level and maintaining soil organic matter . Soil CO2 flux in both the ecosystem it supports . The poster will focus patch types showed rapid and short-lived on the illustration of the model community responses to precipitation, demonstrating as case study of not only sustainable architecture the brief time scales during which soil biota but as example of a biomimetic approach to may process deposited materials . Although design inspired by natural eco-systems . we observed patterns consistent with N limitation of microbes in interspaces, we Has atmospheric nitrogen deposition conclude that atmospheric N deposition altered resource availability to likely accumulates in soils because soil microbes? microbes are primarily limited by water Michelle L . McCrackin1, Tamara K . Harms1, and secondarily by carbon or nitrogen . Nancy B . Grimm1, Sharon J . Hall1, and Soil microbial uptake of atmospherically Jason P . Kaye2 .1School of Life Sciences, deposited N likely occurs only during Arizona State University, Tempe, AZ 85287, sparse and infrequent rainfall . USA, 2Department of Crop and Soil Sciences, Pennsylvania State University, University Effect of water supply on leaf Park, PA 16802, USA stoichiometry in a desert shrub (Zygophyllum xanthoxylum). Terrestrial desert ecosystems are strongly Decao Niu1, James Elser2, Fu Hua1* 1College structured by the distribution of plants, of Pastoral Agricultural Science and Technology, which concentrate resources and create Lanzhou University, Lanzhou 730020, islands of fertility relative to interplant China, 2School of Life Sciences, Arizona spaces . Atmospheric nitrogen (N) deposition State University, Tempe AZ 85287 resulting from urbanization has the potential *Corresponding author to change those spatial patterns via resource inputs . We sampled soils at 12 desert remnant Water often limits plant growth in arid and sites around Phoenix, Arizona along a semiarid ecosystems . However, how water model-predicted gradient in N deposition affects fluxes and partitioning of key elements to determine the degree to which deposition in plants is not obvious, as water stress has altered spatial patterns in soil resource reduces stomatal C transport but also availability and microbial activity . Soil restricts mass flow of nutrients (N, P) into microbial biomass and abundance were roots . This experiment evaluated effects not influenced by atmospheric N deposition . of water on leaf C:N:P stoichiometry in Instead, plant islands remained strong the desert plant Zygophyllum xanthoxylum . organizers of soil microbial processes . Plants were germinated from seed and These islands of fertility exhibited elevated grown at 8 levels of soil water content pools of resources, microbial abundance, (SWC) . When leaves had achieved maximum and activity relative to interspaces . In size, samples were collected for analysis of both plant islands and interspaces, soil Cmass, Nmass and Pmass (% of dry weight moisture and soil N concentrations predicted contributed by each element) and leaf area .

41 Leaf growth was unimodally related to SWC, of shadscale vegetation by weed species . suggesting drought stress at low SWC and The weeds fuel the spread of fires that

waterlog stress at high SWC . Leaf Cmass eliminate shrubs . increased slightly with increasing water; Restoring shadscale vegetation where weeds in contrast, leaf Nmass declined as SWC are now dominant would be very expensive . increased . Leaf Pmass was higher under drier and wetter conditions but lower under Protecting remaining areas of shadscale intermediate water levels . Thus, leaf C: N will require a switch to intensely defensive ratio increased with SWC while leaf C: P management . Critical defenses include ratio and N: P ratio were unimodally related construction of fire breaks between areas to SWC, in parallel with leaf area . As a of weed and shadscale vegetation, elimination result, there were significant positive of livestock grazing and other disturbances correlations between leaf C:P and N:P and that facilitate weed spread, control of leaf growth . Our results indicate that growth antelope and wild horse populations, and and stoichiometry were strongly affected by restoration of native shrubs along roads soil water in this desert shrub . This positive and trails and in former livestock gathering association is consistent with recent areas . Without intensive management much theoretical derivations of growth-stoichiometry of the Great Basin’s shadscale vegetation relations in plants that postulate conditions will be lost . This will probably be accompanied under which plant N: P can be positively or by a reduction of litter accumulation and unimodally related to growth . soil moisture absorption and storage, increased soil erosion, increased temperature Conservation of shadscale vegetation in and moisture extremes, and the decline or the North American Great Basin Desert. extinction of obligate species of plants, 1 2 Garry F . Rogers and Raymond M . Turner . animals and microorganism . 1Agua Fria Open Space Alliance, PO Box 711, Dewey, AZ 86327, 2U . S . Geological Future residential outdoor water Survey (retired), Tucson, Arizona . availability under climatic uncertainty. D .A . Sampson, S K. . Wittlinger, and P . Gober . Native perennial shrub vegetation throughout Decision Center for a Desert City (DCDC), the Great Basin Desert is being replaced Global Institute of Sustainability, Arizona weed communities dominated by Bromus State University, PO Box 878209, Tempe, tectorum (cheatgrass) . The change has been AZ 85287-8209 well documented in upper-valley Artemisia (sagebrush) areas . Our analysis of repeated Uncertainty in surface water supplies as a photographs indicates that a similar change result of climate change may alter future is occurring in the extensive lower-valley water available for outdoor use . We used dwarf shrub vegetation dominated by WaterSim 3 .0, a water simulation model Atriplex confertifolia (shadscale) . The created by DCDC (Gober et al . in review), change appears to reduce productivity, to examine the potential impacts of future stability and biological diversity, and it climatic conditions on residential water represents a regional extirpation and threat supplies for the Phoenix Metropolitan area of eventual extinction for a widespread in 2030 . WaterSim evaluates potential water native vegetation type .The change is supplies in relation to water demand (based occurring because of past and present land on population and individual use) and, in use practices that encouraged infiltration conjunction with policy levers, forecasts the

42 gallons of water available to each individual example, for the most severe climate factor on a daily basis (GPCD) . Water supplies (20% of historical runoff) lot sizes above ~ for the Phoenix metropolitan area come 400 square feet (ft2) could only support xeric from surface sources, which are subject to landscapes in 2030 . We present alternative climate change, and from groundwater strategies for managing future uncertain pumping . Runoff projections for the Salt-Verde water resources . watershed, based on downscaled climate References: Ellis, A W. ., T .W . Hawkins, R .C . Balling, and P . Gober . 2008 . Estimating future runoff levels for a semi-arid models from the 2007 IPCC Assessment fluvial system in central Arizona, USA . Climate Research Report, suggest a potential range in surface 35(3):227-239 . water runoff of -80% to +124% of the historical Gober, P ., E . A . Wentz, T . Lant, M . K . Tschudi, and C . Kirkwood . In review . WaterSim: A simulation model for average (Ellis et al . 2008) . For these analyses urban water planning in Phoenix, Arizona, USA . we assume sustainability in groundwater Environment and Planning B. (recharge = pumping) and constant indoor water use (set at present standards of 78 GPCD) . We focus on the proportion of lot size dedicated to landscape plantings and a continuum of water available for irrigation spanning xeric to mesic landscapes . For

43 photo credit: Jim Elser Addition of surface water and table can limit the amount of moisture ground water interactions in the available in a soil, thereby restricting Variable Infiltration Capacity (VIC) evapotranspiration .Ground water withdrawals land surface model. for municipal, industrial and agricultural Tushar Sinha and John Sabo, School of Life use and its application as irrigation will affect Sciences, Arizona State University, Tempe, streamflow and evapo-transpiration in the AZ 85287 unsaturated soil layers . These effects are currently not included in most of the land Surface water and ground water interactions surface schemes including the Variable directly affect soil moisture and hence alter Infiltration Capacity (VIC) model . Therefore, the energy and water balance fluxes . A the current study focuses to improve shallower water table can supply water to performance of the VIC model to simulate meet the atmospheric demands streamflow and evapotranspiration in semi-arid of evapo-transpiration regions where ground water withdrawals and while deeper water recharge are important .

A deeper spatially variable bottom-most soil layer is created using observed water table depths from near surface aquifer system, physiographic divisions and multilayer soil characteristics

44 photo credit: katsrcool dataset for the conterminous United States Risk mediation in prehistoric irrigation (CONUS-SOIL) . The VIC model is calibrated communities: Exploring the diversification using the naturalized streamflows at selected of farming strategies in arid environments. sites in the Colorado River Basin using Colleen A . Strawhacker . School of Human the variable bottom-most soil layer . USGS Evolution and Social Change, Arizona State observations of water withdrawals, irrigation University, Tempe, AZ and recharge are accounted to those VIC grid cells that are within the spatial extent Prehistoric communities across arid of shallow aquifer system and are influenced environments have utilized a range of by withdrawals . The model simulations are agricultural strategies in order to buffer performed for the Colorado River basin and against environmental variability . Communities the model is finally evaluated using observed that constructed irrigated systems also used streamflow & near surface temperatures . dry farming techniques in order to mediate This modeling framework provides a unique the risk associated with unpredictable opportunity to forecast tradeoffs between floods and droughts that could greatly decrease water for farms, cities and ecosystems the effectiveness of the canals . This poster under climate change . proposes a comparative project, which

45 investigates the varied strategies employed in in riparian cover in the Upper San Pedro order to decrease risk to the production of food, River riparian corridor . Within three focusing on prehistoric irrigated communities geomorphic zones (pre-entrenchment on the arid north coast of Peru and in the floodplain, post-entrenchment floodplain Phoenix Basin . Archaeological and soil and channel), we mapped cover of Populus/ investigations will be the main methodologies Salix forests, other woody vegetation utilized to answer the associated questions (Prosopis and Tamarix), herbaceous/open, in order to compare both irrigated and dry and anthropogenic areas . During the past farmed fields . The environmental impacts half century, the channel has narrowed and temporal variability (i .e . how and when considerably and wooded area on the were each time of field used over time) of each post-entrenchment surfaces has increased type of agricultural strategy will be explored by over 150% . The increase at the southern in order to see how prehistoric farmers were end of the river (where stream flows are able to buffer risk and predict long-term largely perennial) is a result of expansion environmental variability through their of Populus/Salix forests; the increase in the agricultural strategies . northern (and drier) sector is largely a result of expansion of drought-tolerant Riparian forest change following extreme Tamarix . Related modeling efforts predict that disturbance: case study of the upper San the pioneer forests will decline over the coming Pedro River (Arizona). century as senescence exceeds recruitment . Juliet C .Stromberg1, Melanie Tluczek2 and Similar cases of progressive expansion of Andrea F . Hazelton1, 1 School of Life Sciences, pioneer riparian trees following extreme Arizona State University, Tempe, AZ, 85287- disturbance exist on other western North 4501, USA, 2 Applied Biology Sciences, American rivers, and suggest that long-term Arizona State University- Polytechnic, Mesa fluctuations in pioneer forest area are not AZ, 85212, USA uncommon in dryland regions .

In dryland regions, flood regimes are Water for wildlife: Historical non-stationary nd highly variable through actions and future directions. 1 2 time . Extreme flood events can trigger Melanie Tluczek and David E . Brown . 1 large-scale changes that shape vegetation Applied Biological Sciences – Arizona State patterns for decades . Near the turn of University-Polytechnic, Mesa, AZ 85212, the 19th century, intense floods occurred 2School of Life Sciences Arizona State in southern Arizona, following a period University, Tempe, AZ 85287-4501 USA of drought and extensive human impacts (e .g ., cattle grazing) . These floods triggered Since the 1940s, wildlife managers and downcutting of the San Pedro River and conservation groups have installed numerous this entrenchment constituted an extreme and varied water retention devices in the disturbance that substantially altered Southwest deserts in an attempt to stabilize hydro-geomorphology and riparian vegetation . and increase populations of wildlife species Along the San Pedro River, formerly abundant ranging from Gambel’s quail to desert bighorn marshlands and grasslands were largely sheep and Sonoran pronghorn . The implications replaced by pioneer riparian trees which of these efforts, both positive and negative, began to establish in the widening floodplain have been debated by wildlife professionals in the early 1900s . Using a time-series since the 1990s . A number of studies have of georeferenced aerial photographs, we arisen from these debates, addressing quantified recent (1955 to 2003) change issues such as disease, predation, and usage

46 of water developments . Although it has been shown that artificial waters are used by a variety of wildlife species, studies of their effectiveness have resulted in some ambiguity—some species apparently increasing as a result of water developments, others not . Moreover, a full understanding of the affects of these developments on the health, behavior, predator-prey relationship and population level of many species remains enigmatic . Here, we present an overview of historical water provisioning methods, give a brief synthesis of past studies, and track population measurements of select species to identify specific data gaps . We conclude by evaluating several ongoing studies and by suggesting future directions in research revolving around two main themes: the effects of introduced water sources on predator-prey relationships and the development of water budgets for mountain lions, coyotes, and certain sensitive prey species with and without water developments .

The Arizona Rivers Project: Water science, teachers, kids, stewardship. Jim Washburne, Martha P .L . Whitaker, John Madden . UA-Hydrology & Water Resources, SAHRA, Tucson, AZ 85721-0158b, USA

Arizona’s rivers and washes represent some of the most unique and ecologically diverse areas of the state . While Arizona’s riparian environments might not always be obvious, many of us have sampled their richness and have made a commitment to maintain them for the future . Our children and our students can share in this stewardship of the land

47 whilepreparing for challenging technical and scientific careers by undertaking individual and group research projects focused on a multitude of topics ranging from water quality monitoring to invasive species mapping; or Predictability of flowers as a resource from stream restoration to plant or animal in the Chihuahuan Desert. identification and mapping . The Arizona Rivers Karen Wetherill and Kristin Vanderbilt . Project seeks to facilitate student research Sevilleta Long Term Ecological Research skills by promoting partnerships and Program, Department of Biology, University collaborations between watershed and of New Mexico, Albuquerque, NM USA riparian “experts” and the next generation of Arizona citizens and scientists . If you ignore all the green and brown in the desert, you are left with a colorful yet Arizona Rivers involves students and unpredictable landscape of flowers . The volunteers of all ages in addressing issues diversity of flowering plants (in this case, or questions that are developed locally and non-grasses) in arid ecosystems is remarkably pertain to Arizona’s streams, including water high, but their predictability over space and quality, stream restoration, riparian ecology, time is stochastic . The Sevilleta National and habitat preservation . A primary goal Wildlife Refuge (SNWR) sits on the border is to foster effective partnerships among between Chihuahuan desert and Colorado schools, watershed management groups, steppe and has over 300 species of plants . state, county, or municipal regulators, and Monthly plant phenology data has been other water professionals . Workshops in taken for the past nine years at three Tucson, Phoenix, and Flagstaff have been localities on the SNWR, representing held to train teachers, students, water Chihuahuan desert grassland, Chihuahuan professionals, and other volunteer river desert shrubland and Colorado steppe monitors about standard protocols for grassland . Across these three sites, very environmental data collection, and to few species bloom every year and even fewer promote new collaborations and data bloom consistently in the same month exchange . These workshops are crucial each year . Annual turnover rates vary from to offering teachers professional development 26 .8% to 93 .9% with 54 .4% being the in the context of real field experience, average turnover rate . In addition to presence technical training, and collaborations with or absence, dominance of flowers in the professional scientists who can offer support landscape is also unpredictable . Rank and mentorship . (www .azrivers org). abundances change drastically over seasons .

48 The many animals that rely on flowers as over the past thirty years in Arizona using a source of food must be flexible enough historic aerial photography and treatment to deal with this stochasticity or be tuned plant discharge data . We also present a in precisely to the same cues as their host framework for categorizing the fate of flower . Deserts are characterized by the municipal effluent . One aspect includes extremes, not the norms, and the landscape the intended use of the effluent; here, of flowers is no exception . we quantify the degree to which effluent is 1) re-used directly, 2) recharged to Spatial patterns of effluent dependent aquifers for later re-use, or 3) used to waterways in Arizona. create or sustain wetland/riparian habitat . Margaret White and Juliet C . Stromberg . We also categorize effluent discharge with Arizona State University, School of Life respect to hydrogeomorphology of the Sciences, Tempe, Arizona 85287, USA receiving water bodies, recognizing that each type has different capacity to sustain As population centers continue to expand hydroriparian vegetation . Our categories throughout Arizona, societal demands are include 1) ephemeral channels within changing the flow regimes of many rivers an endogenic dryland river; 2) channels and altering spatial patterns across the of perennial or spatially intermittent water landscape . Today, a new hydrologic rivers; 3) stream (alluvial) aquifers, and dynamic has emerged as water consumption 4) regional (interbasin) aquifers . Over the for growing urban development is increasing coming decade both the number of municipal the generation of wastewater effluent and its discharge points and the total effluent discharge into stream channels or aquifers . discharge is expected to increase, As of 2008 Arizona has approximately 40 intensifying the need to understand waterways designated as effluent- dependent . ecological implications of effluent We present an analysis of the changing dependent systems . spatial patterns of effluent discharge and development of effluent dependent waterways