This study demonstrates the utility of carbon isotope discrimination in describing genetic adaptation to arid environments, although it is probably most useful in detecting differentiation when the strategy of the species under investigation is to increase water use efficiency, rather than drought-avoidance. The results suggest that populations on the eastern and western sides of the Andes should be treated as separate management units for the purposes of conserving the genetic resource of this species.Resource Type: Journal Papers
National Parks and other protected areas not only provide a safe haven for biodiversity, they provide benefits to local communities and preserve some of the most beautiful places on our planet. ‘Coverage of protected areas’ is also a specific indicator in the 2010 Target of the Convention on Biological Diversity.
Obtaining the data necessary to monitor trends in protected areas requires a massive effort by national authorities to compile, analyse and then distribute this data to the centralised depository of the World Database on Protected Areas (WDPA). With a living and growing system of protected areas that now exceed 100,000 sites covering 19 million square kilometres, you can imagine that this is no small task!
The threat posed to coral reefs by biological invasion is unlikely to diminish and should therefore be considered in analyses of the effectiveness of Marine Protected Areas.Resource Type: Journal Papers
An assessment of impacts on Arctic terrestrial ecosystems has emphasized geographical variability in responses of species and ecosystems to environmental change. This variability is usually associated with north-south gradients in climate, biodiversity, vegetation zones, and ecosystem structure and function. It is clear, however, that significant east-west variability in environment, ecosystem structure and function, environmental history, and recent climate variability is also important.Some areas have cooled while others have become warmer.
Overall, the subregional synthesis demonstrates the difficulty of generalizing projections of responses of ecosystem structure and function, species loss, and biospheric feedbacks to the climate system for the whole Arctic region and implies a need for a far greater understanding of the spatial variability in the responses of terrestrial arctic ecosystems to climate change.Resource Type: Journal Papers
Global and regional coral reef area statistics are of considerable value in fields ranging from global environmental change to fisheries to conservation. Although widely quoted, Smith's 1978 figure of 600 000rkm2 is only an approximate calculation. The World Conservation Monitoring Centre has prepared a new estimate of reef coverage by mapping emergent reef crest and very shallow reef systems. These data were rasterised, using 1rkm grid squares, as a means of reducing errors arising from variation in scale. Global and regional reef coverages were calculated from the resultant grid. The total global area is estimated at 255 000rkm2, considerably lower than many previous estimates. Variation in reef area estimates is, in part, a function of variation in reef definition.Resource Type: Journal Papers
Since about 1600, 486 animal species have been recorded extinct. This represents about 0.04 of all animal species so far described. In the same period, 600 plant species are known to have disappeared, about 0.25 of the total. These figures are much smaller than those of the Permian/Triassic and Cretaceous/Tertiary mass extinctions. One might therefore conclude that at present life on earth is at comparatively little risk of extinction. However, there is a growing body of data to show that the converse is true.Resource Type: Journal Papers
The countries affected by the 2004 Asian tsunami contain the most diverse and extensive coral reefs and mangroves of the Indian Ocean, and some of the richest in the world. Not only are these ecosystems among the most threatened in the world, they also provide numerous essential ecosystem services.
It is thus not surprising that reefs and mangroves received widespread attention after the tsunami, with three principal questions posed: Are the tsunami's impacts on reefs and mangroves a further threat to their future survival? Did reefs and mangroves play a role in shoreline protection and reduce structural damage and human mortality? How could reconstruction efforts include actions to maintain these ecosystems and reduce further threats to them?Resource Type: Journal Papers
Coral reefs are the most biologically diverse of shallow water marine ecosystems but are being degraded worldwide by human activities and climate warming. Analyses of the geographic ranges of 3235 species of reef fish, corals, snails, and lobsters revealed that between 7.2 and 53.6 of each taxon have highly restricted ranges, rendering them vulnerable to extinction. Restricted-range species are clustered into centers of endemism, like those described for terrestrial taxa. The 10 richest centers of endemism cover 15.8 of the world's coral reefs (0.012 of the oceans) but include between 44.8 and 54.2 of the restricted-range species. Many occur in regions where reefs are being severely affected by people, potentially leading to numerous extinctions. Threatened centers of endemism are major biodiversity hotspots, and conservation efforts targeted toward them could help avert the loss of tropical reef biodiversity.Resource Type: Journal Papers
Projections indicate that species and ecosystems will be at maximum risk from human activities during the next few decades. Prompt action by the world community can minimise the eventual loss of species. Highest priorities should be to: (i) strengthen the management of ecosystems containing a large proportion of global biodiversity; (ii) help developing countries complete their biodiversity strategies and action plans, monitor their own biodiversity, and establish and maintain adequate national systems of conservation areas; (iii) support actions at the global level, providing benefit to all countries in managing their own biodiversity. Generally, resources will best be spent in safeguarding ecosystems and habitats that are viable and important for global biodiversity, and which are threatened by factors that can be controlled cost-effectively. Other important criteria are representativeness, complementarity and insurance.Resource Type: Journal Papers
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