Since the 1950s, humans have changed ecosystems more than during any other similar span in history, causing staggering losses of biodiversity. Informed policy is urgently required to slow these losses, but is hampered by the lack of a consistent scientific framework for tracking the conservation status of Earth’s ecosystems, and of objective and transparent criteria for identifying those more likely to disappear. Recognizing this major scientific gap, the IV IUCN World Conservation Congress (Barcelona, Spain, 5-14 October, 2008) set in motion a process to develop risk assessment criteria that will eventually lead to a new tool for conservation policy: a global IUCN Red List of Ecosystems.
The new system and the already well established Red List of Threatened Species are designed to complement each other and provide better measures of biodiversity loss and recovery. Monitoring the status of both species and ecosystems provides a more complete picture of the state of biodiversity. Ecosystems may collapse, while species that lived in them continue to live elsewhere or within novel ecosystems. Likewise species may go extinct even though the ecosystems in which they occurred remain functional and unperturbed.
The Red List of Ecosystems uses categories that are very similar to the ones in the species Red List. The endpoint of ecosystem decline is collapse which is for example the analogous concept of species extinction. The risk of collapse is evaluated using five criteria based on variables which may be specific to particular ecosystem types with appropriate standardization procedures:
(A) ongoing declines in distribution, indicating ongoing threatening processes that result in ecosystem loss
(B) restricted distribution, which predisposes the system to spatially explicit threats, along with manifested
decline, threat or fragmentation.
(C) degradation of the abiotic environment, reducing habitat quality or abiotic niche diversity for component biota (e.g. ocean acidification,soil fertility loss).
(D) disruption of biotic processes and interactions, which can result in the loss of mutualisms, biotic niche diversity or exclusion of component biota.
(E) quantitative estimates of the risk of collapse.
A paper that provides guidance to the application of the Red List of Ecosystems Categories and Criteria has been published in the Philosophical Transactions of the Royal Society as part of a discussion meeting issue. The paper makes a very interesting read especially if you are not familiar with this new system. I have to admit that I belong to the group of people that didn't know much about it before, maybe heard about it once or twice, but never learned about it in more detail. This paper represents a very good start and now I will have a closer look at all the other contribution to this special issue. The theme is 'Phylogeny, extinction and conservation’. Sounds promising.
h/t Alexander Weigand
h/t Alexander Weigand