Biological Consequences of Ecosystem Fragmentation: A Review

Abstract

Abstrack Resemcb on fragmented ecosystems bas focused mostly on tbe biogeograpbic consequences of tbe creation of habitat "islands" of d i f f m t s i z e and bas p v f d e d little of practical value to managers H o m , ecosystem fragmentation causes large changes in tbepbysfcal environment as well as biogeograpbic changes Fragmentation generally msults in a landscape that consists of remnant areas of native vegetation surrounded by a mdrlx of agricultural or otber developed land As a mu14 fluxes of radiation, momentum (La, wind), water, and nutrients clcros~ tbe landsare altered significantly. Tbese in turn can haw important influences on tbe biota witbin remnant are-especially at or near tbe edge between tbe remnant and tbe surrounding matrix Tbe isolatfon of remnant areas by clearing also bas important consequences for tbe biota These consequences vary with tbe time since isolatioq distance from otber remnants, and d e p of connectivity witb otber remnants Tbe influences of pbysical and biogeographic changes are modified by tbe size, sbape, and p i t i o n in tbe landscape of individual remnanQ witb larger remnants being less aduwsely affected by tbejhapaentation process @vtuamicr Resumen. La inwstigaci6n sobre 10s ecosistemasfragmentados se ba e n f d principlmente en las c o n s~i a s biogeograficas de la maci6n de "islas" de bdbitat de diferentes tammios y ha s & de muy poco valorprdctico para 10s m a r w j h s del mcurso. Como quiera que seq la fragmenkui6n de 10s ecosistemas causa grandes cambios en el medio ambiente fkico asi como en el ambito biogeografica La fragmentaci6n resulta generalmente en terrenos que consisten de areas remanentes de vegetacidn ruativa r o d e de una mat& de tierras agricolas u otras formas de us0 de la tima Como un resultado & estq el flujo de la radiaci6n, del momentum (eJ el viento), del agua y de 10s nutrientes a t r a h de la tierra son alterados significativatnente. Esto en su turn, puerle influencim e la biota & r a m de kas amas remanentes, especialmente en o cerca de 10s limites entre 10s remanentes y la matrix que 10s &a El aislamiento de las h a s remanentespor la tala tambikr tiene imporkmtes consecuenciaspara la biota y estas consecuetacias vmlan con, el tiempo desde el momento del aislamientq la distancia basta 10s ohas remanentes y el grad0 de coneccidn entre ella La influencia de 10s cambios frSic0s y biogeogrdficos es modiJicadapor el tamatio, la fonna y la posici6n en el t m de rpmanentes indioiduales siendo 10s remanentes gmndes 10s menos afecWos adwmamante por el proceso de flagmentaci6n La didmica de las &tws remanmtes son dirigidas 18 Conservation Biology Volume 5, No. 1, M v c h 1991 S a u n d m et al. Consequences of Rqgmenpzp'on 19of remnant areas me predominantly driven by factors arising in tbe smunding krndscu#~e Management oJ and research on, fiagmented ecosystems sbould be directed at understanding and controlling tbese external influences as mu& as at tbe biota of tbe remnants themselves Tbere is a strong need to develop an integrated appmach to l...

Movements of Marine Fish and Decapod Crustaceans: Process, Theory and Application

“…Levin and Paine, 1974;Steele, 1978;Paine and Levin, 1981;Sousa, 1984;. It is in terrestrial environments, however, that the quantification of landscape pattern and the study of the effect of pattern on ecological processes have made significant advances in understanding animal movement and persistence, the effects of disturbance, the importance of broad-scale environmental change and the design of resource management strategies (Turner, 1989;Saunders et al, 1991;Hobbs, 1994;Forman, 1995;Farina, 1998). Landscape ecology principles and tools are applicable throughout ecology and recent reviews have outlined the usefulness of a landscape ecology approach for the marine environment (Kneib, 1994;Robbins and Bell, 1994;Bell et al, 1997;Irlandi and Crawford, 1997;Eggleston, 1999).…”

Historical changes in caribou distribution and land cover in and around Prince Albert National Park: land management implications

“…In highly fragmented landscapes, the decline of wildlife popu¬ lations is greater than that expected by habitat loss alone (Andren, 1994) and ultimately, these changes to the landscape can isolate groups of animals (Belisle & Desrochers, 2002). Habitat fragmentation is consid¬ ered one of the greatest threats to biodiversity mak¬ ing it an important conservation issue (Harris, 1984;Forman & Godron, 1986;Saunders et al, 1991).…”

Are bird song complexity and song sharing shaped by habitat structure? An information theory and statistical approach

“…There is 82 considerable evidence that habitat fragmentation can cause declines in avian populations 83 (Bender et al, 1998;Schmiegelow and Monkkonen, 2002). The main reasons of these 84 species' declines are a reduction of habitat areas (area effect) and an increase in distance 85 between remaining habitat patches that influences therefore dispersal ability (isolation 86 effect, Andrén, 1994; Opdam et al, 1994; reviewed in Saunders et al, 1991;Debinski 87 and Holt, 2000). Habitat fragmentation has been suggested to condition song variation in 88 some bird species (white crowned sparrow Zonotrichia leucophrys nuttalli, Trainer,89 1983; corn bunting Miliaria calandra, Holland et al, 1996), but direct evidence has only 90 been shown in the Dupont's lark Chersophilius duponti Tella, 2005, 2007).…”