Titre :	Consequences of global warming for biological diversity
Type de document :	texte imprimé
Auteurs :	Robert L. Peters, Auteur
Editeur :	Chapman and Hall
Année de publication :	1991
Importance :	p 99-118
Langues :	Anglais (eng)
Catégories :	SCIENCES DE L'ENVIRONNEMENT
Mots-clés :	EFFET DE SERRE  BIODIVERSITE  CHANGEMENT CLIMATIQUE  CHANGEMENT LATUDINAL PROJETE
Résumé :	In the geologic past, natural climate changes have caused large-scale geographic shifts in species’ ranges, changes in species composition of biological communities and species extinctions. If the widely predicted greenhouse effect occurs, natural ecosystems will respond in ways similar to the ways they did in the past but the response must be more extreme because of the very rapid rate of the projected change. Moreover, population reduction and habitat destruction due to human activities will prevent many species from colonizing new habitat when their old habitat becomes unsuitable. The synergy between climate change and habitat destruction due to human activities will prevent many more species than either factor alone. These effects would be pronounced in temperate and arctic regions , where tempertaure increases are projected to be relatively large. It is unclear how affected the tropical biota would be by the relatively small temperatures increases projected for the lower latitudes, because relatively little is known about the physiological tolerances of tropical species, but substantial disruption may occur due to precipitation changes. Throughout the world, geographically restricted species might face extinction, whereas widespread species are likely to survive in some parts of their range. In the northern mid- and high latitudes, new northward habitat will become suitable even as die-offs occur to the south. However, it may be difficult for many species to take advantage of this new habitat because dispersal rates for many species are slow relative to the rate of warming and therefore, ranges of even many widespread species are likely to show a net decrease during the next century. Range retractions will be proximally caused by temperature and precipitation changes, increases in fires, changes in the ranges and severity of pests and pathogens, changes in competitive interactions and additional effects of nonclimatic stresses like acid rain and low-level ozone. The best solutions to the ecological upheaval resulting from climatic change are not yet clear. In fact, little attention has been paid to the problem. What is clear, however is that the climatological changes wpould have tremendous impact on communities and populations isolated by development and, by the middle of the next century, may dwarf any other consideration in planning for reserve management. The problem may seem overwhelming . One thing is, worth keeping in mind : if populations are fragmented and small, they are more vulnerable to the new stresses brought about by climate change. Thus, one of the best things that can be done in the short-term is to minimize further encroachment of development upon existing natural ecosystems. Furthermore, we must refine climatological predictions and increase understanding of how climate affects species, both individually and in their interactions with each other. Such studies may allow us to identify those areas where communities will be most stressed as well as alternate areas where they might best be saved. Meanwhile, efforts to improve techniques for managing communities and ecosystems under stress, and also for restoring them when necessary, must be carried forward energetically.
Numéro du document :	A/MAC
Niveau Bibliographique :	2
Bull1 (Theme principale) :	METEOROLOGIE ,ATMOSPHERE,CLIMATOLOGIE
Bull2 (Theme secondaire) :	ATMOSPHERE,CLIMATOLOGIE-CONSIDERATION GENERALE

Consequences of global warming for biological diversity [texte imprimé] / Robert L. Peters, Auteur . - Chapman and Hall, 1991 . - p 99-118.
Langues : Anglais (eng)

Catégories :	SCIENCES DE L'ENVIRONNEMENT
Mots-clés :	EFFET DE SERRE  BIODIVERSITE  CHANGEMENT CLIMATIQUE  CHANGEMENT LATUDINAL PROJETE
Résumé :	In the geologic past, natural climate changes have caused large-scale geographic shifts in species’ ranges, changes in species composition of biological communities and species extinctions. If the widely predicted greenhouse effect occurs, natural ecosystems will respond in ways similar to the ways they did in the past but the response must be more extreme because of the very rapid rate of the projected change. Moreover, population reduction and habitat destruction due to human activities will prevent many species from colonizing new habitat when their old habitat becomes unsuitable. The synergy between climate change and habitat destruction due to human activities will prevent many more species than either factor alone. These effects would be pronounced in temperate and arctic regions , where tempertaure increases are projected to be relatively large. It is unclear how affected the tropical biota would be by the relatively small temperatures increases projected for the lower latitudes, because relatively little is known about the physiological tolerances of tropical species, but substantial disruption may occur due to precipitation changes. Throughout the world, geographically restricted species might face extinction, whereas widespread species are likely to survive in some parts of their range. In the northern mid- and high latitudes, new northward habitat will become suitable even as die-offs occur to the south. However, it may be difficult for many species to take advantage of this new habitat because dispersal rates for many species are slow relative to the rate of warming and therefore, ranges of even many widespread species are likely to show a net decrease during the next century. Range retractions will be proximally caused by temperature and precipitation changes, increases in fires, changes in the ranges and severity of pests and pathogens, changes in competitive interactions and additional effects of nonclimatic stresses like acid rain and low-level ozone. The best solutions to the ecological upheaval resulting from climatic change are not yet clear. In fact, little attention has been paid to the problem. What is clear, however is that the climatological changes wpould have tremendous impact on communities and populations isolated by development and, by the middle of the next century, may dwarf any other consideration in planning for reserve management. The problem may seem overwhelming . One thing is, worth keeping in mind : if populations are fragmented and small, they are more vulnerable to the new stresses brought about by climate change. Thus, one of the best things that can be done in the short-term is to minimize further encroachment of development upon existing natural ecosystems. Furthermore, we must refine climatological predictions and increase understanding of how climate affects species, both individually and in their interactions with each other. Such studies may allow us to identify those areas where communities will be most stressed as well as alternate areas where they might best be saved. Meanwhile, efforts to improve techniques for managing communities and ecosystems under stress, and also for restoring them when necessary, must be carried forward energetically.
Numéro du document :	A/MAC
Niveau Bibliographique :	2
Bull1 (Theme principale) :	METEOROLOGIE ,ATMOSPHERE,CLIMATOLOGIE
Bull2 (Theme secondaire) :	ATMOSPHERE,CLIMATOLOGIE-CONSIDERATION GENERALE