DOCSLIB.ORG

Transient Phenomena in Ecology

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Transient Phenomena in Ecology RESEARCH ◥ a systematic study of transient dynamics in REVIEW SUMMARY ecological systems. As illustrated in the figure, a relatively small number of ideas from dynam- ical systems are used to categorize the differ- ECOLOGY ent ways that transients can arise. Translating these abstract results from dynamical systems Transient phenomena in ecology into observations about both ecological models ◥ and ecological system dy- ON OUR WEBSITE namics, it is possible to un- Alan Hastings*, Karen C. Abbott, Kim Cuddington, Tessa Francis, Gabriel Gellner, Read the full article derstand when transients Ying-Cheng Lai, Andrew Morozov, Sergei Petrovskii, at http://dx.doi. arelikelytooccurandthe Katherine Scranton, Mary Lou Zeeman org/10.1126/ various properties of these science.aat6412 transients, with implica- .................................................. BACKGROUND: Much of ecological theory transient is a persistent dynamical regime— tions for ecosystem man- and the understanding of ecological systems including near-constant dynamics, cyclic dy- agement and basic ecological theory. Transients has been based on the idea that the observed namics, or even apparently chaotic dynamics— can provide an explanation for observed re- states and dynamics of ecological systems can that persists for more than a few and as many gime shifts that does not depend on under- be represented by stable asymptotic behavior as tens of generations, but which is not the sta- lying environmental changes. Systems that of models describing these systems. Beginning ble long-term dynamic that would eventually continually change rapidly between different with early work by Lotka and Volterra through occur. These examples have demonstrated the long-lasting dynamics, such as insect outbreaks, Downloaded from the seminal work of May in the 1970s, this view potential importance of transients but have may most usefully be viewed using the frame- has dominated much of ecological thinking, often appeared to be a set of idiosyncratic work of long transients. although concepts such as the idea of tipping cases. What is needed is an organized approach An initial focus on conceptual systems, such points in ecological systems have played an that describes when a transient behavior is as two-species systems, establishes the ubiq- increasingly important role. In contrast to the likely to appear, predicts what factors enhance uity of transients and an understanding of implied long time scales of asymptotic behavior long transients, and describes the character- what ecological aspects can lead to transients, http://science.sciencemag.org/ in mathematical models, both observations of istics of this transient behavior. A theory of long includingthepresenceofmultipletimescales ecological systems and questions related to the ecological transients is a counterpart to the and particular nonlinear interactions. The in- management of ecological systems are typically related question of tipping points, where pre- fluences of stochasticity and more realistic focused on relatively short time scales. vious work based on an analysis of simple bi- higher-dimensional dynamics are shown to A number of models and observations demon- furcations has provided broad insights. increase the likelihood, and possibly the tem- strate possible transient behavior that may poral extent, of transient dynamics. persist over very long time periods, followed ADVANCES: Just as ideas based on the saddle- by rapid changes in dynamics. In these ex- node bifurcation provide a basis for under- OUTLOOK: The development of such a frame- amples, focusing solely on the long-term be- standing tipping points, a suite of ideas from work for organizing the study of transients in havior of systems would be misleading. A long dynamical systems provides a way to organize ecological systems opens up a number of on September 11, 2018 avenues for future research and application. The approach we describe also raises impor- AB tant questions for further development in dy- Long transient before continuing cycle namical systems. We have not, for example, emphasized nonautonomous systems, which Slow change mayberequiredtounderstandtheimplica- during a saddle tions of a changing environment for transients. Species 2 crawl-by “landscape” Systems with explicit time dependence as well as stochastic nonlinear systems still present Population dynamic great mathematical challenges. Slow change in Implications for management and basic Species 1 system state near ecological understanding depend on both the ghost attractor results we describe and future developments. A recognition of the difficulty of prediction caused by long transients, and of the corre- Long transient sponding need to match dynamics to transient before reaching behaviors of models, shows that basing either stable state (well) Multiple High management or interpretation of ecological Stochasticity time scales dimension observations only on long-term dynamics can be seriously flawed.▪ Two ways that long transients arise in ecology, illustrated as a ball rolling downhill. (A)Slow transition away from a ghost attractor: a state that is not an equilibrium, but would be under slightly different conditions. (B) Lingering near a saddle: a state that is attracting from The list of author affiliations is available in the full article online. *Corresponding author. Email: [email protected] some directions but repelling from others. Additional factors such as stochasticity, multiple time Cite this article as A. Hastings et al., Science 361, eaat6412 scales, and high system dimension can extend transients. (2018). DOI: 10.1126/science.aat6412 Hastings et al., Science 361, 990 (2018) 7 September 2018 1of1 RESEARCH ◥ point.” In turn, the directional change in pa- REVIEW rameter values is often assumed to result from an exogenous process such as, for instance, global climate change. Intense study of one kind of ECOLOGY exogenously triggered regime shift (those caused by saddle-node bifurcations) has provided im- portant insights (3, 5, 6) across a range of eco- Transient phenomena in ecology logical systems. There is, however, a growing body of evidence that we review here, from both Alan Hastings1*, Karen C. Abbott2, Kim Cuddington3, Tessa Francis4, Gabriel Gellner5, empirical and modeling studies, suggesting alter- Ying-Cheng Lai6, Andrew Morozov7,8, Sergei Petrovskii7, native underlying mechanisms for some regime Katherine Scranton9, Mary Lou Zeeman10 shifts. The approach for understanding regime shifts The importance of transient dynamics in ecological systems and in the models that describe can be extended to a much broader range of them has become increasingly recognized. However, previous work has typically treated phenomena and systems by focusing on transients each instance of these dynamics separately. We review both empirical examples and model in ecological systems, where once again ideas from systems, and outline a classification of transient dynamics based on ideas and concepts dynamical systems can organize what may at first from dynamical systems theory. This classification provides ways to understand the likelihood appear to be a disparate set of observations and of transients for particular systems, and to guide investigations to determine the timing explanations. In the cases we focus on here, the ecological dynamics are essentially transient of sudden switches in dynamics and other characteristics of transients. Implications for both Downloaded from 7–12 management and underlying ecological theories emerge. ( ) and shifts occur in the absence of any clear trend in the environmental properties. Ecological transients can arise for a number of nderstanding ecological dynamics over cilitate understanding of transient dynamics, reasons, including responses to environmental relevant time scales underpins almost all each example appears novel and idiosyncratic. fluctuation as well as a variety of human inter- major questions in ecology, such as ex- Concepts from dynamical systems (Table 1) can ventions. Some transients are short; others can U planations for observed distributions and provide tools for a more systematic approach last for a very long time. An ecosystem exhibit- http://science.sciencemag.org/ abundances of species, population changes to the incorporation of transient dynamics in ing long transient behavior would typically show through time, and management of ecological ecological models and theories, as well as guide an apparently stable dynamic (e.g., periodic os- systems. There is a growing recognition that applications to natural and managed systems. cillations,asinFig.1,A,D,andE)overtimethat dynamics on ecological time scales, called tran- Tools will emerge for understanding which eco- may span dozens or even hundreds of genera- sients, may be different from asymptotic dynamics. logical factors produce long transients, and for tions before experiencing a sudden transition to The inherent impermanence of transients means identifying appropriate responses to the possi- another state (e.g., extinction) or another regime that an ecological system in a transient state can bility of sudden system changes in management (e.g., oscillations with a very different mean change abruptly, even without any underlying and in experimental and observational studies. value). Therefore, long transients may provide change in environmental conditions (parameters). A major ecological question is how to relate Conversely, the possibility of long transients im- observations of
Load more

Recommended publications
  • 1999 May 23–27; Mi
    The Evolving Role of Science in Wilderness to Our Understanding of Ecosystems and Landscapes Norman L. Christensen, Jr. Abstract—Research in wilderness areas (areas with minimal Disturbance and Change _________ human activity and of large spatial extent) formed the foundation for ecological models and theories that continue to shape our Henry Chandler Cowles’ (1899, 1901) studies of succes- understanding how ecosystems change through time, how ecologi- sion on sand dunes newly exposed by the retreat of the Lake cal communities are structured and how ecosystems function. By Michigan shoreline initiated a search for a unifying theory the middle of this century, large expanses of wilderness had of ecosystem change that continues to this day. Cowles’ become less common and comparative studies between undis- primary interest was in understanding the relationship turbed and human-dominated landscapes were more prevalent. between the process of vegetation change and landform Such studies formed the basis an evolving understanding of hu- evolution. He did not advocate a unifying theory for succes- man impacts on ecosystem productivity and biogeochemical cy- sional change in this work, but his assertions on several cling. Research in the last third of this century has repeatedly important points were central to the evolution of such a taught us that even the most remote wilderness areas are not free theory. These assertions included directional change con- of human influence. Nevertheless, extensive wilderness has been verging on a stable climax community and “biotic reaction,” and will continue to be critical to our understanding our impacts that is, organismal influences on the environment as a on nonwilderness landscapes.
    [Show full text]
  • MU Ecological Succession
    ECOLOGICAL SUCCESSION Prepared by Dr. Rukhshana Parveen Assistant Professor, Department of Botany Gautum Buddha Mahila College, Gaya Magadh University, Bodhgaya Ecological Succession is also called as Plant Succession or Biotic succession. Hult (1885) used the term” succession”. The authentic studies on succession were started in America by Cowles (1899) and Clements (1907). The occurrence of relatively definite sequence of communities over a long period of time in the same area resulting in establishment of stable community is called ecological succession. It allows new areas to be colonized and damaged ecosystems to be recolonized, so organisms can adapt to the changes in the environment and continue to survive. Major types of ecological succession. 1. Primary Succession- When the succession starts from barren area such as bare rock or open water. It is called primary succession. Figure1:- Primary succession. 2. Secondary Succession- Secondary succession occurs when the primary ecosystem gets destroyed by fire or any other agent. It gets recolonized after the destruction. This is known as secondary ecological succession. Figure2:- Secondary succession. 3. Autogenic succession:- After succession has begun, Its vegetation itself cause its own replacement by new communities is called Autogenic succession 4. Cyclic Succession: - This refers to repeated occurrence of certain stages of succession. 5. Allogenic succession:- When the replacement of existing community is caused by any other external condition and not by existing vegetation itself. This is called allogenic succession. 6. Autotropoic succession:- It is characterised by early and continued dominance of autotrophic organism called green plants. 7. Heterotropic succession:- It is characterised by early dominance of heterotrophs such as bacteria, actinomycetes, fungi and animal.
    [Show full text]
  • Distributional Dynamics in the Hawaiian Vegetation!
    Pacific Science (1992), vol. 46, no. 2: 221-231 © 1992 by University of Hawaii Press. All rights reserved Distributional Dynamics in the Hawaiian Vegetation! DIETER MUELLER-DOMBOIS 2 ABSTRACT: Vegetation ecology is usually divided into two broad research areas, floristic/environmental gradient analysis and studies of vegetation dy­ namics. The early influential American ecologist Clements combined the two areas into a dynamic system for classifying vegetation. His succession and climax theory, however, was later severely criticized. A new approach to the study of distributional dynamics, called "landscape ecology," focuses on the dynamics of spatial vegetation patterns. There is a spatial hierarchy rule, which implies greater stability of species and community patterns when one considers larger area units versus smaller ones. It is argued that this rule is frequently transgressed in biotically impoverished areas, like the Hawaiian Islands, where certain dominant plant species have become established over unusually broad areas and habitat spectra. A further point made is that with "species packing" successional patterns change from auto-succession, where the dominant species retains dominance by in situ generation turnover (termed chronosequential monoculture), via "normal" succession (i.e., displacement ofdominants by other dominants over time [termed chronosequentialpolyculture]), to small-area patch or gap dynamics (termed chronosequential gap rotation). Examples of the three spatially different succession paradigms are given for Hawaii, and the point is made that chronosequential monocultures cannot be expected to last, but change to chronosequential gap rotation with the invasion of alien dominants. Before the invasion of alien dominants, certain native dominants seem to have segregated into races or varieties by evolutionary adaptation to successional habitats.
    [Show full text]
  • Nature Conservation and Grazing Management
    Nature conservation and grazing management Free-ranging cattle as a driving force for cyclic vegetation succession Jan Bokdam Promotor Prof. dr. F. Berendse Hoogleraar Natuurbeheer en Plantenecologie, Wageningen Universiteit Promotiecommissie Prof. dr. R. Marrs University of Liverpool, United Kingdom Prof. dr. J.P. Bakker Rijksuniversiteit Groningen Prof. dr. ir. H. van Keulen Wageningen Universiteit Prof. dr. J. Sevink Universiteit van Amsterdam Nature conservation and grazing management Free-ranging cattle as a driving force for cyclic vegetation succession (met een Nederlandse samenvatting) Jan Bokdam Proefschrift ter verkrijging van de graad van doctor op gezag van de rector magnificus van Wageningen Universiteit Prof. dr. ir. L. Speelman in het openbaar te verdedigen op vrijdag 11 april 2003 des namiddags te vier uur in de Aula. ISBN 90-5808-791-3 Printed by Ponsen & Looyen b.v., Wageningen. This study was carried out at the Nature Conservation and Plant Ecology Group, Department of Environmental Sciences, Wageningen University, Bornsesteeg 69, 6708 PD Wageningen, in co-operation with the Vereniging Natuurmonumenten, ’s Graveland. Most of the chapters in this thesis have been or will be published as articles in scientific journals. You are kindly requested to refer to these articles rather than to this thesis. This thesis should be cited as follows: J. Bokdam (2003) Nature conservation and grazing management. Free-ranging cattle as a driving force for cyclic succession. PhD thesis. Wageningen University, Wageningen, The Netherlands. voor Margaret, Johan, Maarten en Wouter Alles hangt met alles samen Alles verandert - Panta rhei (Heraclitus, ca. 500 v.C.) Abstract Bokdam, J. (2003). Nature conservation and grazing management.
    [Show full text]
  • Transition Dynamics in Succession: Implications for Rates, Trajectories and Restoration
    In: Suding, K. and R. J. Hobbs, editors. 2008. Chapter 3, New Models for Ecosystem Dynamics and Restora‐ tion. Island Press. Transition Dynamics in Succession: Implications for Rates, Trajectories and Restoration Lawrence R. Walker School of Life Sciences University of Nevada, Las Vegas 4505 Maryland Parkway Las Vegas, NV 89154-4004, USA and Roger del Moral Department of Biology University of Washington Seattle, WA 98195-5325, USA Succession provides a temporal framework in ize (del Moral 2000). Ultimately, successional communi- which to understand ecological processes. Studies of ties can be characterized by a range of processes from qu- community assembly and changes in species diversity and asi-equilibrium to non-equilibrium dynamics depending nutrient cycling, for example, benefit greatly from the on the time scales involved (Briske et al. 2003). temporal perspective that succession offers. The temporal Restoration research has benefited from (stable) consequences of species interactions throughout the life state and transition models (Bestelmeyer et al. 2003, Grant history of each species are also well integrated into the 2006) because these models focus on mechanisms that conceptual framework of successional dynamics. With an cause transitions between successional stages and provide emphasis on species effects on community dynamics, suc- explicit goals for restoration. Transitions are integral to cession has been a nexus for physiological, population, restoration as they are the process of community level ecosystem and landscape ecology as well as for biogeo- change following a disturbance and may move the system graphy, geology, soil science and other disciplines. With either toward or away from the desired state. These tran- its temporal focus that demands recognition of the ubi- sitions lead to sometimes predictable but often unpredict- quitous forces of change, succession thus provides insights able or even novel patterns of community change.
    [Show full text]
  • Transient Phenomena in Ecology
    RESEARCH ◥ a systematic study of transient dynamics in REVIEW SUMMARY ecological systems. As illustrated in the figure, a relatively small number of ideas from dynam- ical systems are used to categorize the differ- ECOLOGY ent ways that transients can arise. Translating these abstract results from dynamical systems Transient phenomena in ecology into observations about both ecological models ◥ and ecological system dy- ON OUR WEBSITE namics, it is possible to un- Alan Hastings*, Karen C. Abbott, Kim Cuddington, Tessa Francis, Gabriel Gellner, Read the full article derstand when transients Ying-Cheng Lai, Andrew Morozov, Sergei Petrovskii, at http://dx.doi. arelikelytooccurandthe Katherine Scranton, Mary Lou Zeeman org/10.1126/ various properties of these science.aat6412 transients, with implica- .................................................. BACKGROUND: Much of ecological theory transient is a persistent dynamical regime— tions for ecosystem man- and the understanding of ecological systems including near-constant dynamics, cyclic dy- agement and basic ecological theory. Transients has been based on the idea that the observed namics, or even apparently chaotic dynamics— can provide an explanation for observed re- states and dynamics of ecological systems can that persists for more than a few and as many gime shifts that does not depend on under- be represented by stable asymptotic behavior as tens of generations, but which is not the sta- lying environmental changes. Systems that of models describing these systems. Beginning ble long-term dynamic that would eventually continually change rapidly between different with early work by Lotka and Volterra through occur. These examples have demonstrated the long-lasting dynamics, such as insect outbreaks, Downloaded from the seminal work of May in the 1970s, this view potential importance of transients but have may most usefully be viewed using the frame- has dominated much of ecological thinking, often appeared to be a set of idiosyncratic work of long transients.
    [Show full text]
  • Carrying Capacity Carrying Capacity Is Typically Defined As the Maximum Population Size That Can Be Supported Indefinitely by a Given Environment
    Carrying capacity Carrying capacity is typically defined as the maximum population size that can be supported indefinitely by a given environment. The simplicity of this definition belies the complexity of the concept and its application. There are at least four closely related uses of the term in basic ecology, and at least half a dozen additional definitions in applied ecology. Basic Ecology Carrying capacity is most often presented in ecology textbooks as the constant K in the logistic population growth equation, derived and named by Pierre Verhulst in 1838, and rediscovered and published independently by Raymond Pearl and Lowell Reed in 1920: where N is the population size or density, r is the intrinsic rate of natural increase (i.e., the maximum per capita growth rate in the absence of competition), t is time, and a is a constant of integration defining the position of the curve relative to the origin. The expression in brackets in the differential form is the density-dependent unused growth potential, which approaches 1 at low values of N, where logistic growth approaches exponential growth, and equals 0 when N=K, where population growth ceases. That is, the unused growth potential lowers the effective value of r (i.e., the per capita birth rate minus the per capita death rate) until the per capita growth rate equals zero (i.e., births=deaths) at K. The result is a sigmoid population growth curve (Figure 1). Despite its use in ecological models, including basic fisheries and wildlife yield models, the logistic equation is highly simplistic and much more of heuristic than practical value; very few populations undergo logistic growth.
    [Show full text]
  • Population Dynamics, Disturbance, and Pattern Evolution
    Botany Publication and Papers Botany 9-1998 Population Dynamics, Disturbance, and Pattern Evolution: Identifying the Fundamental Scales of Organization in a Model Ecosystem Thorsten Wiegand UFZ-Centre for Environmental Research Kirk A. Moloney Iowa State University, [email protected] Suzanne J. Milton University of Cape Town Follow this and additional works at: http://lib.dr.iastate.edu/bot_pubs Part of the Botany Commons, Other Ecology and Evolutionary Biology Commons, Other Plant Sciences Commons, and the Terrestrial and Aquatic Ecology Commons Recommended Citation Wiegand, Thorsten; Moloney, Kirk A.; and Milton, Suzanne J., "Population Dynamics, Disturbance, and Pattern Evolution: Identifying the Fundamental Scales of Organization in a Model Ecosystem" (1998). Botany Publication and Papers. 62. http://lib.dr.iastate.edu/bot_pubs/62 This Article is brought to you for free and open access by the Botany at Iowa State University Digital Repository. It has been accepted for inclusion in Botany Publication and Papers by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. Population Dynamics, Disturbance, and Pattern Evolution: Identifying the Fundamental Scales of Organization in a Model Ecosystem Abstract We used auto- and cross-correlation analysis and Ripley’s K-function analysis to analyze spatiotemporal pattern evolution in a spatially explicit simulation model of a semiarid shrubland (Karoo, South Africa) and to determine the impact of small-scale disturbances on system dynamics. Without disturbance, local dynamics were driven by a pattern of cyclic succession, where ‘‘colonizer’’ and ‘‘successor’’ species alternately replaced each other. This results in a strong pattern of negative correlation in the temporal distribution of colonizer and successor species.
    [Show full text]
  • Excerpts of Text Citing Connel and Slatyer (1977)
    Excerpts of text citing Connel and Slatyer (1977) A typical approach to restoration has been to plant the suite of species found in an intact community relict. However, it is possible that there are necessary but fully transient community states that occur during succession (Connel and Slatyer 1977). This phenomenon improves micro-site conditions, which allow occupation of the same species, or others and thus influences species richness (Connel and Slatyer 1977). Connel and Slatyer (1977) proposed three models of succession: (1) facilitation, in which early species modify the environment to make it more suitable for later colonizers; (2) tolerance, in which, as the environment changes, established species exhibit a progressive tolerance of invading species; and (3) inhibition, in which early colonizers restrict the invasion of later colonizers. Therefore BSCs enhance the probability of colonization and survival of later successional species according to the facilitation model of Connel and Slatyer (1977). The shift could thus be due to facilitation of N-demanding species (Connel and Slatyer 1977). The classic facilitation, tolerance, and inhibitory models of succession proposed by Connel and Slatyer (1977), based on the net effect of early colonists on later ones, have been widely used to classify successional patterns in terrestrial and aquatic systems (Bertness 1991, De Steven 1991, Farrell 1991). This implied that, regardless of dominant exotic species, all patch types were roughly equivalent at inhibiting native grass recruitment from added seed (Connel and Slatyer 1977). Connel and Slatyer (1977) identied three models of succession during community development in which early successional species can have either a positive (facilitation), neutral (tolerance), or negative (inhibition) effect on the establishment of later species.
    [Show full text]
  • Towards a Unifying Theory of Vegetation Dynamics
    TOWARDS A UNIFYING THEORY OF VEGETATION DYNAMICS by Madhur Anand Department of Plant Sciences [Environmental Science] Subrnitted in partial filfillrnent of the requirements for the degree of Doctor of Philosophy Faculty of Graduate Studies The University of Western Ontario London, Ontario May 1997 National Libraiy Bibliothèque nationale !*m of Canada du Canada Acquisitions and Acquisitions et Bibliographie SeMces senrices bibliographiques 395 Wellington Street 395, rue Wellington OttawaON K1AON4 Ottawa ON KIA ON4 Canada Carlada The author has granted a non- L'auteur a accorde une licence non exclusive licence allowing the exclusive permettant à la National Library of Canada to Bibliothèque nationale du Canada de reproduce, loan, distribute or sell reproduire, prêter, distribuer ou copies of this thesis in microform, vendre des copies de cette thèse sous paper or electronic formats. la forme de microfiche/film, de reproduction sur papier ou sur format électronique. The author retains ownership of the L'auteur conserve la propriété du copyright in ths thesis. Neither the droit d'auteur qui protège cette thèse. thesis nor substantid extracts fiom it Ni la thèse ni des extraits substantiels may be printed or otherwise de celle-ci ne doivent être imprimés reproduced without the author's ou autrement reproduits sans son permission. autorisation. ABSTRACT The thesis to be argued is that vegetation dynamics is a unified, complex chaotic process, hierarchically unfolding over spatio-temporal scales, where determinism and randomness convolute, shifting in dominance through sequential phases. Conventional theory, known as the Clements-Gleason controversy, views determinism and randomness as mutually exclusive phenornena. My goal is to prove conventional theory wrong.
    [Show full text]
  • Vegetation Dynamics and Dynamic Vegetation Science Van Der Maarel, E
    University of Groningen Vegetation dynamics and dynamic vegetation science Van der Maarel, E Published in: Acta Botanica Neerlandica IMPORTANT NOTE: You are advised to consult the publisher's version (publisher's PDF) if you wish to cite from it. Please check the document version below. Document Version Publisher's PDF, also known as Version of record Publication date: 1996 Link to publication in University of Groningen/UMCG research database Citation for published version (APA): Van der Maarel, E. (1996). Vegetation dynamics and dynamic vegetation science. Acta Botanica Neerlandica, 45(4), 421-442. Copyright Other than for strictly personal use, it is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license (like Creative Commons). Take-down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. Downloaded from the University of Groningen/UMCG research database (Pure): http://www.rug.nl/research/portal. For technical reasons the number of authors shown on this cover page is limited to 10 maximum. Download date: 24-09-2021 Bot. Acta Need. 45(4), December 1996, p. 421-442 REVIEW Vegetation dynamics and dynamic vegetation science* Eddy van der Maarel Department of Ecological Botany and Ecological Research Station Oland, Uppsala University, Villavdgen 14, S-752 36 Uppsala, Sweden: Department
    [Show full text]