Evaluation of farmland productivity after rural homestead reclamation in the Three Gorges Reservoir Area - A case study of Fuling District, Chongqing City Characteristics and soil anti-erodibility effects of mulberry forest lands at different altitudes of water-level fluctuation zone of the Three Gorges Reservoir Research progress on the effects of the Three Gorges Reservoir on the ecological environment Evaluation and changing characteristics of fertilizer input in different agricultural systems in the Three Gorges Reservoir Area