ECA_3_Executive summary_b_194;195

If key knowledge gaps would be addressed soon, future assessments could provide a more comprehensive account of the relationship between biodiversity and nature’s contributions to people and of the status and trends of nature (well established) (3.6). Much more information is available on the relationship between biodiversity and ecosystem services from experiments than from the field. Among the experiments those manipulating plant diversity were overrepresented compared with those manipulating other taxa, and most concerned grasslands or aquatic mesocosms. For experiments and field studies addressing the relationship between biodiversity and ecosystem services, comprehensive information across all types of nature’s contributions is not yet available (well established) (3.2, 3.6). A broader knowledge basis on trends in habitat extent, intactness and species conservation status was available for Western and most of Central Europe than for Eastern Europe, Central Asia and Balkan countries in Central Europe (3.4, 3.6). For example, exact extent, biodiversity status and trends are hardly known for most terrestrial and freshwater ecosystems in Eastern Europe and Central Asia, and the chemical status of 40% of Western and Central Europe’s surface waters remains unknown (well established). Biodiversity status and trends are also poorly known for most marine habitats. E.g. 30% of coastal marine habitat assessments in the Mediterranean reported unknown conservation status. Only a minor fraction of the deep-sea floor and of known seamounts have been subject to biological investigation (well established) (3.4, 3.6). Major gaps on status and trends of taxonomic groups concerned invertebrates, most marine and freshwater species, bryophytes, lichens, fungi and microorganisms. Of the estimated 32,000 vascular plant species of Europe and Central Asia, IUCN evaluated 2,483 (approx. 8%) in the Red List of Threatened Species. Of the estimated more than 2,000 bryophyte and more than 7,000 lichen species in the region only 14 and 5 species, respectively, have been evaluated in the IUCN Red List. For invertebrates in general, and freshwater invertebrates in particular, even the current status is available only for a minority of species. Almost a quarter of all European freshwater molluscs are data deficient, many of them likely to be threatened. 76% of freshwater fishes and 83% of freshwater molluscs assessed have unknown population trends (well established) (3.4). One to two thirds of marine species are still to be described. Status and trends for marine biodiversity are mostly unknown, even for coastal habitats. Accordingly, 50% of the assessments under the European Union Habitats Directive reported unknown conservation status for cetaceans and turtles and coastal marine habitats in the Macaronesian biogeographic region. And 30% of coastal marine habitat assessments in the Mediterranean reported unknown conservation status. Only a minor fraction of the deep-sea floor and of known seamounts have been subject to biological investigation (well established) (3.3., 3.4, 3.6). Indigenous and local knowledge on biodiversity trends was only partially available (well established) (3.6). Due to lack of quantitative knowledge the relative role of drivers of change in determining trends in extent and intactness of habitats and in species diversity and abundance could only be attributed in terms of a coarse classification. Moreover, information is lacking on the interacting effects of several drivers on biodiversity (well established) (3.3, 3.4, 3.6) These knowledge gaps greatly reduce the ability to monitor progress towards international biodiversity targets and to inform policy to avert further biodiversity loss. For example, current instruments such as the European Union Habitats Directive and Natura 2000 programme do not consider algae, fungi or lichens, and only a small fraction of invertebrates (well established) (3.6).