Definition: Biodiversity, or biological diversity, is usually defined as the variety and variability of living organisms and the biological communities in which they live, plus the ecological and evolutionary processes that keep them functioning. There are four levels of diversity: genetic, species, ecosystem, and landscape. (Library of Congress, Tracer bullet 97-5)
For a list of international agreements on this topic see the Joint Web Site of the Biodiversity Related Conventions and the CIESIN thematic guide to the Convention on Biological Diversity
GEO Data portal (UNEP) is the authoritative source for data sets used by UNEP and its partners in the Global Environment Outlook (GEO) report and other integrated environment assessments. Its online database holds more than 500 different variables, as national, subregional, regional and global statistics or as geospatial data sets (maps), covering themes like Freshwater, Population, Forests, Emissions, Climate, Disasters, Health and GDP. Display them on-the-fly as maps, graphs, data tables or download the data in different formats.
Earth Trends a comprehensive online database, maintained by the World Resources Institute, that focuses on the environmental, social, and economic trends that shape our world.
Biodiversity Hotspots maps and statistics from Conservation International, a non-governmental interest group. To qualify as a hotspot, a region must meet two strict criteria: it must contain at least 1,500 species of vascular plants (> 0.5 percent of the world’s total) as endemics, and it has to have lost at least 70 percent of its original habitat.
Australia and New Zealand
International intergovernmental organizations with Biodiversity or Sustainable Development mandates:
Canadian Environmental Regulation and Compliance News - links to provincial and federal regulatory sites
Non-governmental organizations or sites with Biodiversity or Sustainable Development resources: