Abstract:

Hedgerow intercropping is a comprehensive agroforestry technique with the ecobenefits of soil improvement,soil particle interception,soil conservation,soil fertility enhancement and nonpoint pollution controlling.To evaluate the ecobenefits of hedgerows with different categories and species,42 hedgerow inventory plots were arranged in the Jiangjin city of the Three Gorges reservoir area.The properties containing bulk density,moisture content,saturated water conductivity,water stable aggregates,antiscouribility index,antierodibility,organic matter and soil nutrients concentration of soil which sampled before,behind and under hedgerows,and between hedgerows steep land were tested to evaluate the ecobenefits of hedgerow.According to the principle of Analytical Hierarchy Process (AHP),the evaluating indicators system involving soil improvement,soil conservation,soil fertility enhancement and nonpoint pollution controlling containing 17 indicators were established.The weights values were calculated by Entropy and Delphi which help to avoid the subjectivity of experts in computing weights values,and AHP combined to calculate the comprehensive ecobenefits values.And then,the ecobenefits with different categories and species in the Three Gorges reservoir area were compared according the comprehensive ecobenefits values.The results indicated that,the shrub hedgerows had the best ecobenefits among the hedgerows with different categories,and shrub hedgerows were of excellent benefits in soil improvement,soil conservation,soil fertility enhancement and nonpoint pollution controlling.Among different species,hedgerows with Vitex negundo and Ailanthus altissima had the best comprehensive ecobenefits,Giycine maxhedgerows were of the excellent benefits in soil fertility enhancement,hedgerows with Gynura bicolor and Herba Rorippae were the best one in nonpoint source (NPS) pollution controlling