s:785:"%T Biodiversity and agroecosystem function %A Agus, F. %A van Noordwijk, M. %X Agroecosystems are ecosystems in which humans have exerted a deliberate selectivity on the composition of the biota, i.e. the crops and livestock maintained by the farmer, replacing to a greater or lesser degree the natural flora and fauna of the site. The establishment and management of a modified and simplified plant community, often including exotic species, influences the composition and activities of the associated herbivore, predator, symbiont and decomposer sub-communities (Figure 11.1; Swift and Anderson 1993). The composition, diversity, system structure and dynamics of agroecosystems may thus differ in many respects from those of the natural ecosystems of the adjacent landscape. ";