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Habitat Fragmentation and Biodiversity Conservation: Key Findings and Future Challenges [Landscape Ecol, DOI: 10.1007/S10980-015-0312-3]

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Habitat Fragmentation and Biodiversity Conservation: Key Findings and Future Challenges [Landscape Ecol, DOI: 10.1007/S10980-015-0312-3] UC Davis UC Davis Previously Published Works Title Erratum to: Habitat fragmentation and biodiversity conservation: key findings and future challenges [Landscape Ecol, DOI: 10.1007/s10980-015-0312-3] Permalink https://escholarship.org/uc/item/4fz8r8md Journal Landscape Ecology, 31(2) ISSN 0921-2973 Authors Wilson, MC Chen, XY Corlett, RT et al. Publication Date 2016-02-01 DOI 10.1007/s10980-015-0322-1 Peer reviewed eScholarship.org Powered by the California Digital Library University of California Landscape Ecol DOI 10.1007/s10980-015-0312-3 EDITORIAL Habitat fragmentation and biodiversity conservation: key findings and future challenges Maxwell C. Wilson . Xiao-Yong Chen . Richard T. Corlett . Raphael K. Didham . Ping Ding . Robert D. Holt . Marcel Holyoak . Guang Hu . Alice C. Hughes . Lin Jiang . William F. Laurance . Jiajia Liu . Stuart L. Pimm . Scott K. Robinson . Sabrina E. Russo . Xingfeng Si . David S. Wilcove . Jianguo Wu . Mingjian Yu Received: 5 November 2015 / Accepted: 7 November 2015 Ó Springer Science+Business Media Dordrecht 2015 Habitat loss and fragmentation has long been consid- fragmented landscapes across the word (Haddad et al. ered the primary cause for biodiversity loss and 2015), altering the quality and connectivity of habitats. ecosystem degradation worldwide, and is a key Therefore, understanding the causes and conse- research topic in landscape ecology (Wu 2013). quences of habitat fragmentation is critical to preserv- Habitat fragmentation often refers to the reduction of ing biodiversity and ecosystem functioning. continuous tracts of habitat to smaller, spatially From May 4th to 10th, 2015, an International distinct remnant patches, and habitat loss typically Workshop on Habitat Fragmentation and Biodiversity occurs concurrently with habitat fragmentation (Col- Conservation, held at the Thousand Island Lake, linge 2009). Although some habitats are naturally Zhejiang, China, discussed threats to biodiversity in patchy in terms of abiotic and biotic conditions (Wu fragmented landscapes and how fragmentation and Loucks 1995), human actions have profoundly research can identify and help mitigate these threats. M. C. Wilson Á J. Wu P. Ding (&) Á J. Liu Á X. Si Á M. Yu (&) School of Life Sciences, Arizona State University, College of Life Sciences & Institute of Ecology, Zhejiang Tempe, AZ 85287, USA University, Hangzhou 310058, Zhejiang, China e-mail: [email protected] e-mail: [email protected] M. Yu X.-Y. Chen e-mail: fi[email protected] School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200214, China R. D. Holt Department of Biology, University of Florida, R. T. Corlett Á A. C. Hughes Gainesville, FL 32611, USA Centre for Integrative Conservation, Xishuangbanna Tropical Botanic Garden, Chinese Academy of Sciences, M. Holyoak Menglun, Mengla 666303, Yunnan, China Department of Environmental Science and Policy, University of California, Davis, CA 95616, USA R. K. Didham School of Animal Biology, University of Western G. Hu Australia, Perth, WA 6009, Australia Department of Landscape Architecture, School of Civil Engineering and Architecture, Zhejiang University of R. K. Didham Science and Technology, Hangzhou 310018, Zhejiang, CSIRO Land and Water, Centre for Environment and Life China Sciences, Perth, WA 6014, Australia 123 Landscape Ecol To meet these challenges, the Workshop had three (Fahrig 2003); however, newer research suggests that goals. The first was to synthesize key findings in indirect and interaction effects may be the dominant fragmentation science. Second was to identify impor- driver of the ecological changes often attributed to tant remaining research questions concerning the habitat loss alone (Didham et al. 2012). relationships between habitat fragmentation, biodi- • Species richness often changes significantly with versity, and ecosystem functioning at local, regional, fragmentation (MacArthur and Wilson 1967; Dia- and global scales. Finally, we examined the unique mond 1975). Nonetheless, other measures of com- roles of field-based fragmentation experiments in munity structure, such as community composition, addressing these questions. The Workshop’s findings trophic organization, species persistence, and spe- are relevant to the broader ecological community, and cies residency, may better inform how fragmenta- we present them here to stimulate research that will tion affects biotic communities, even when species advance landscape ecology and conservation biology. richness per se is not altered by fragmentation (Robinson et al. 1992; Haddad et al. 2015). • As habitat loss results in changes in both the Key findings concerning habitat loss amount and configuration of habitat (e.g., and fragmentation decreased patch size, increased patch isolation, and increased edge area), fragmentation-mediated processes cause generalizable responses at the • While habitat fragmentation ultimately derives from population, community, and ecosystem levels. habitat loss, three broadly defined mechanisms These include decreased residency within and mediate the ecological consequences of fragmenta- movement among fragments, reduced species tion. First, there are those attributable directly to the richness across taxonomic groups, and decreased loss of habitat area. Second, there are those nutrient retention (Haddad et al. 2015). By com- attributable directly to changes in the spatial config- paring findings across multiple landscape-scale uration of the landscape, such as isolation. Finally, fragmentation experiments, one can partition there are those attributable to indirect or interaction effectively the relative influence of increasing effectsofhabitatlossandchangesinspatialconfig- habitat loss, patch isolation, and edge influence on uration (Didham et al. 2012), and to the interaction of different community and ecosystem attributes fragments with the matrix (e.g., spillover effects). A (Haddad et al. 2015), and potentially distinguish review of the literature found that when one ignores generalizable consequences of fragmentation from indirect and interaction effects, the impacts of habitat more idiosyncratic, system-specific responses. loss are far greater than changing habitat configuration L. Jiang S. E. Russo School of Biology, Georgia Institute of Technology, School of Biological Sciences, University of Nebraska- Atlanta, GA 30332, USA Lincoln, Lincoln, NE 68588, USA W. F. Laurance D. S. Wilcove Centre for Tropical Environmental and Sustainability Woodrow Wilson School of Public and International Science, James Cook University, Cairns, QLD 4878, Affairs, Princeton University, Princeton, NJ 08544, USA Australia D. S. Wilcove W. F. Laurance Department of Ecology and Evolutionary Biology, College of Marine and Environmental Sciences, James Princeton University, Princeton, NJ 08544, USA Cook University, Cairns, QLD 4878, Australia J. Wu S. L. Pimm School of Sustainability, Arizona State University, Nicholas School of the Environment, Duke University, Tempe, AZ 85287, USA Durham, NC 27708, USA S. K. Robinson Florida Museum of Natural History, University of Florida, Gainesville, FL 32611, USA 123 Landscape Ecol • Area and isolation effects encompass a variety of not fully understand the ways in which these systems ecological processes that can complicate our converge and diverge from each other, creating a understanding of fragmentation. For example, primary source of confusion within the study of reductions in patch size and increases in edge- fragmentation. affected area can influence local ecosystem pro- cesses indirectly through microclimatic effects. To What factors affect the relative balance between top- make results more generalizable, studies should down and bottom-up processes in fragmented decompose area and isolation effects into direct, landscapes? ecologically relevant, mechanistic drivers such as microclimate, local matrix quality, and vulnera- Community ecologists have long recognized that both bility to stochastic events (e.g., Laurance et al. top–down (predator–mediated) and bottom–up (pro- 2011). ducer–mediated) processes can influence community composition. However, our understanding of how top- down and bottom-up dynamics might interact across geographic space is limited (Gripenberg and Roslin Remaining questions and challenges 2007), although it is clear that spatial factors such as patch size could potentially impact the strength of Despite the progress made in formalizing fragmenta- trophic cascades (Terborgh 2010). Fragmented habi- tion science, significant questions remain. tats present an excellent platform for examining the interaction between these forces over a variety of Local community-level dynamics spatial scales. How do conditions at the time of fragmentation impact How do the processes of dispersal and ecological community structure and dynamics? filtering—exclusion due to the effects of environmental and biotic conditions—interact to structure Historically the term fragmentation has been used to biodiversity? describe the ecological changes arising from two different landscape contexts. The first of these are Although both dispersal- and niche-mediated mecha- relaxing systems—those intact at the time of frag- nisms affect community assembly, the importance of mentation and which are now relaxing to few species the interaction between these processes in high- and diminished ecosystem function (e.g., Laurance diversity communities is still largely unknown (Myers et al. 2011). In contrast, assembling systems are those and Harms 2011).
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