farmland use耕地利用farmlandn.农田farmland ecological bearing capacity农用地生态承载力farmland loss caused by construction建设占用耕地farmland of government official study官学学田farmland collection and control system农田采集控制系统farmland non-agricultural conversion农地非农流转Farmland information collection system农田信息采集系统farmland sectional altitude difference田间微地形偏差Farmland occupation-compensation balance占补平衡Farmland irrigation and water conservation农田水利farmland requisition-compensation balance耕地占补平衡