Biodiversity -The UN defines biodiversity as "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”.
Ecosystems - An ecosystem is a dynamic complex of flora (plants), fauna (animals), microbes (microorganisms such as bacteria) and their non-living environment (soil, air, water) interacting with one another as a functional unit. Examples of ecosystems are forests, grass-lands and urban areas.