In matters relating to the environment, the United Nations Conference on Environment and Development, held in June 1992 in Rio de Janeiro, produced an “ Earth Charter”, or declaration of basic principles for the conduct of nations and peoples with respect to environment and development; agreements on specific legal measures, including conventions （公约）on climate change and biodiversity, and principles for a framework agreement on forests; and an agenda for action （ “Agenda 21”）, establishing the environmental work program agreed by the international community for the period beyond 1992 and into the twenty-first century.