[20210708]IF11871_生物多样性.pdf

https:/crsreports.congress.gov July 8, 2021BiodiversityBiodiversity refers to the variety of life on Earth, and definitions of biodiversity generally encompass measures of diversity at the genetic, species, and ecosystem levels. Assessing changes in biodiversityincluding both losses and gainsat all three of these levels and the causes, or drivers, of these changes is of interest to many scientists and other stakeholders. Addressing biodiversity, including biodiversity loss and the potential consequences for humans, is also of interest to some Members of Congress. Some Members have introduced legislation in the 117th Congress that aims to conserve species and ecosystems. Definition of Biodiversity There are many definitions of biodiversity. Many include similar concepts to the definition provided by the United Nations Convention on Biological Diversity (CBD): biological diversity is “the variability among living organisms from all sources including, inter alia, terrestrial, marine and other aquatic ecosystems and the ecological complexes of which they are part; this includes diversity within species, between species and of ecosystems.” Some definitions also consider fluctuations to