Sustainability requires living within the regenerative capacity of the biosphere. In an attempt to measure the extent to which humanity satisfies this requirement, we use existing data to translate human demand on the environment into the area required for the production of food and other goods, together with the absorption of wastes. Our accounts indicate that human demand may well have exceeded the biosphere's regenerative capacity since the 1980s. According to this preliminary and exploratory assessment, humanity's load corresponded to 70% of the capacity of the global biosphere in 1961, and grew to 120% in 1999.
Resource Type: Journal PapersThe 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 PapersHorizon scanning identifies emerging issues in a given field sufficiently early to conduct research to inform policy and practice. Our group of horizon scanners, including academics and researchers, convened to identify fifteen nascent issues that could affect the conservation of biological diversity. These include the impacts of and potential human responses to climate change, novel biological and digital technologies, novel pollutants and invasive species. We expect to repeat this process and collation annually.
Resource Type: Journal PapersCoral 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 PapersAssuming no radical transformation in human behavior, we can expect important changes in biodiversity and ecosystem services by 2050. A considerable number of species extinctions will have taken place. Existing large blocks of tropical forest will be much reduced and fragmented, but temperate forests and some tropical forests will be stable or increasing in area, although the latter will be biotically impoverished. Marine ecosystems will be very different from today's, with few large marine predators, and freshwater biodiversity will be severely reduced almost everywhere. These changes will not, in themselves, threaten the survival of humans as a species.
Resource Type: Journal PapersWe applied a conceptual framework and score-card developed by the Cambridge Conservation Forum (CCF) to a sample of 60 conservation activities to determine the predictive power of implementation measures versus measures of key outcomes (later steps in the models defined in the CCF tools). We show that assessing key outcomes is often more difficult than quantifying the degree of implementation of a project but that, while implementation is a poor predictor of success, key outcomes provide a feasible and much more reliable proxy for whether a project will deliver real conservation benefits. The CCF framework and evaluation tool provide a powerful basis for synthesizing past experience and, with wider application, will help to identify factors that affect the success of conservation activities.
Resource Type: Journal PapersThe 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 PapersOur analyses show significant differences between predictions from different models, with predicted changes in range size by 2030 differing in both magnitude and direction (e.g. from 92 loss to 322 gain). We explain differences with reference to two characteristics of the modelling techniques: data input requirements (presence/absence vs. presence-only approaches) and assumptions made by each algorithm when extrapolating beyond the range of data used to build the model. The effects of these factors should be carefully considered when using this modelling approach to predict species ranges. Main conclusions We highlight an important source of uncertainty in assessments of the impacts of climate change on biodiversity and emphasize that model predictions should be interpreted in policy-guiding applications along with a full appreciation of uncertainty.
Resource Type: Journal PapersThe effects of Pleistocene glaciations on the genetic characteristics of the most austral conifer in the world, Pilgerodendron uviferum, were analysed with specific reference to the hypothesis that the species persisted locally in ice-free areas in temperate South America.
Results indicated that Pilgerodendron populations are highly monomorphic, probably reflecting past population bottlenecks and reduced gene flow. Southernmost populations tend to be the least genetically variable and were therefore probably more affected by glacial activity than northern ones. Populations located outside ice limits seem to have been isolated during the glacial period. The presence of centres of genetic diversity, together with the lack of a significant correlation between genetic and geographical distances and the absence of geographical patterns of allelic frequencies at most analysed alleles, may indicate that Pilgerodendron did not advance southward after the last glaciation from a unique northern refugium, but spread from several surviving populations in ice-free areas in Patagonia instead.
Resource Type: Journal PapersGlobal 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.
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