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1.
PLoS One ; 7(3): e32529, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22457717

RESUMO

Protected areas (PAs) are a cornerstone of conservation efforts and now cover nearly 13% of the world's land surface, with the world's governments committed to expand this to 17%. However, as biodiversity continues to decline, the effectiveness of PAs in reducing the extinction risk of species remains largely untested. We analyzed PA coverage and trends in species' extinction risk at globally significant sites for conserving birds (10,993 Important Bird Areas, IBAs) and highly threatened vertebrates and conifers (588 Alliance for Zero Extinction sites, AZEs) (referred to collectively hereafter as 'important sites'). Species occurring in important sites with greater PA coverage experienced smaller increases in extinction risk over recent decades: the increase was half as large for bird species with>50% of the IBAs at which they occur completely covered by PAs, and a third lower for birds, mammals and amphibians restricted to protected AZEs (compared with unprotected or partially protected sites). Globally, half of the important sites for biodiversity conservation remain unprotected (49% of IBAs, 51% of AZEs). While PA coverage of important sites has increased over time, the proportion of PA area covering important sites, as opposed to less important land, has declined (by 0.45-1.14% annually since 1950 for IBAs and 0.79-1.49% annually for AZEs). Thus, while appropriately located PAs may slow the rate at which species are driven towards extinction, recent PA network expansion has under-represented important sites. We conclude that better targeted expansion of PA networks would help to improve biodiversity trends.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Animais , Extinção Biológica , Plantas/classificação
2.
Cell Biol Toxicol ; 24(6): 475-81, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18335319

RESUMO

Science-based indicators aimed at measuring the sustainability of human activities on the environment have become of prime importance in the policy arena. At the international level, the Commission on Sustainable Development and the Convention on Biological Diversity and other Multilateral Environmental Agreements have recognised the need to develop a set of scientific indicators related to changes in biodiversity and other environmental issues able to direct policy decisions. In the marine realm, the study of the effects of both 'top-down' extractive activities such as fishing is more and more dealt with, in conjunction with 'bottom-up' activities such as nutrient loading and the effects on biogeochemical cycles, marine geochemistry and ecosystem structure and functioning of other pollutants and contaminants. 'Conventional' approaches such as the identification of taxa, model organisms and related methodologies will continue playing a key role for the monitoring of human-induced changes in the marine environment. On the other hand, newly developed disciplines such as genomics, proteomics and biodiversity informatics are increasingly looked at as a source of information and applications that can respond to questions and concerns by the policy community such as the need to adapt to global and climate change in the marine environment so as to mitigate its societal implications.


Assuntos
Meio Ambiente , Biologia Marinha/métodos , Biologia Marinha/tendências , Política Pública , Animais , Monitoramento Ambiental , Pesquisa
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