Impacts of Biodiversity Loss on Ocean Ecosystem Services

The significance of Biodiversity especially in the worlds oceans is important. This article describes how human ties to global fisheries are only possible in the future if the fragile biodiversity is restored and maintained. "What is the role of biodiversity of in maintaining the ecosystem services on which a growing human population depends? Recent surveys of terrestrial literature suggest that local species richness may enhance ecosystem productivity and stability. However, the importance of biodiversity changes at the landscape level is less clear, and the lessons from local experiments and theory do not seem to easily extend to long term, large scale management decisions. These issues are particularly enigmatic for the world's oceans, which are geographically large taxonomically complex, making the scaling up from local to global scales potentially more difficult." Part of the solution require better understanding of the three dimensional ocean ecosystem. More experimentation is required to make more effective policies of conservation. "In summary, experimental results indicate robust positive linkages between biodiversity, productivity, and stability across trophic levels in marine ecosystems. Identified mechanisms from the original studies include complementary resource use, positive interactions, and increased selection of highly performing species at high diversity." A few of the issues that the world's ocean's are global warming, affluent runoff from industry, high pressure fishing practices and coastal development. "A mechanism that may explain enhanced recovery at high diversity is that fishers can switch more readily among target species, potentially providing over fished taxa with a chance to recover. Indeed, the number of fished taxa was a log-linear function of species richness was negatively related to the variation in catch from year to year and positively correlated with the total production of catch per year. This increased stability and productivity are likely due to the portfolio effect, whereby a more diverse array of species provides a larger number of ecological functions and economic opportunities over time. This portfolio effect has independently been confirmed by economic studies of multispecies been confirmed by economic studies of multispecies harvesting relationships in marine ecosystems. Linear (or log-linear) relationships indicate steady increases in services up to the highest levels of biodiversity.This means that proportional species losses are predicted to have similar effects at low and high levels of native biodiversity." The writer is optimistic that it is possible for many areas to be rehabilitated back to their full potential. "Community variability, as measured by the coefficient of variation in aggregate fish biomass, was reduced by 21% on average. Finally tourism revenue measured as the relative increase in dive trips within 138 Caribbean protected areas strongly increased after the were established." Summarizing the this summery with this passage. "High diversity systems consistently provided more services with less variability, which has economic and policy implications. First, there is no dichotomy between biodiversity conservation and long term economic development; they must be view as interdependent societal goals. Second, there was no evidence for redundancy at high levels of diversity; the improvement of services was continues on a log-linear scale. Third, the buffering impact of species diversity of ecosystem services generates insurance value that must be incorporated into future economic valuations and management decisions."

Citations:
Impacts of Biodiversity Loss on Ocean Ecosystem Services
by: Boris Worm et al.

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