An Agroecosystem is land used for crops, pasture, and livestock; the adjacent uncultivated land that supports other vegetation and wildlife; and the associated atmosphere, the underlying soils, groundwater, and drainage networks.

Other /More definition:
An agroecosystem is a dynamic association of crops, pastures, livestock, other flora and fauna, atmosphere, soils and water. Agroecosystems are contained within larger landscapes that include uncultivated land, drainage networks, rural communities. and wildlife.