Abstract: How to assess the global biodiversity and predict its declining trend and associated impacts on the well-being of mankind has turned out to be one of the important orientations of the current study on biodiversity over the world.The connotation of, approaches to and achievements in global biodiversity assessment have been elaborated by combining recent advancement in the study on global biodiversity assessment. The conceptual framework of driving-force-pressure-state-impact-response (DPSIR) is currently the major framework in use in most biodiversity assessment projects. Based on objectives of the assessments, the methods of biodiversity assessment can be classified into three main types, i.e. index assessment, model simulation, and scenario analysis. Currently, the global 2010 target assessment index framework, the integrated model to assess the global environment (IMAGE)/GLOBIO model, and the scenario models set up on environmental outlooks of Special Report on Emissions Scenarios(SRES)of Intergovernmental Panel on Climate Change(IPCC), Millennium Ecosystem Assessment(MA), Global Environment Outlook(GEO), and Organization for Economic Cooperation and Development(OECD) are most commonly used in the global assessment projects. The results of a number of global assessment projects show that the declining trend of the global biodiversity has not yet been effectively curbed, and will even be accelerated in this century. In the future, the study should go deep in understanding the relationship between biodiversity, ecosystem service and human well-being, and exploring for development of a 2020 global assessment index framework and a multi-scenario, multi-model and multi-ecosystem based integrated biodiversity assessment method. China should conscientiously sum up its experience in studying theories and methodology for global biodiversity assessment, strengthen construction of its 2020 target assessment index framework and biodiversity monitoring network, develop area-specific integrated biodiversity assessment models and scenario analysis methods with proprietary intellectual property rights, conduct periodically integrated assessment of the biodiversity of the country, get to know status quo and developing trend of its biodiversity, so as to provide services to its decision-makers in respect to preservation and management of biodiversity.

Key words: biodiversity assessment, assessment index, model, scenario analysis