覆盖方式对浙西低丘橘园土壤碳库和养分流失的影响

Effects of Mulching Methods on Soil Carbon Pool and Nutrient Loss in Low Hilly Orange Orchards in Western Zhejiang

设置了对照(清园)、秸秆覆盖、自然生草和人工种草4个处理,比较了不同覆盖方式对丘陵红壤区柑橘土壤有机质、养分、水分、地表径流量、地表径流中泥沙和养分流失量以及柑橘产量和品质等的影响,以期为南方果园科学管理提供依据。结果表明:3种不同处理方式促进了表土不同形态的有机质积累,提高了水稳定性团聚体含量和土壤水分贮量并降低了表层的土壤容重。3种覆盖方式的综合效果以秸秆覆盖最佳,秸秆覆盖后的土壤碳库管理指数较对照提高了55.00%,年累计径流量、泥沙流失量、全氮和全磷流失量较对照分别降低了61.27%、89.31%、79.24%和87.50%。秸秆覆盖处理可小幅提高柑橘产量,显著提高柑橘的糖度,降低其可滴定酸含量。综上所述,低丘果园行间覆盖农作物秸秆具有良好的生态效应,能够有效减少养分流失,改善土壤理化性质和生态环境,可作为南方丘陵果园生态优化的水保措施。

The effects of different mulching methods on soil properties,carbon pool,and surface nutrient loss of citrus gardens in hilly red soil areas were explored,which could provide a basis for scientific management of orchards in southern China.Four treatments including control(garden cleaning),straw mulching,natural grass planting and artificial grass planting were set up.The effects of different mulching methods on soil organic matter,nutrients,soil moisture,surface runoff loss,and soil and nutrient loss in surface runoff were compared and studied.The results showed that mulching citrus orchards with the above three different methods could improve the accumulation of organic matter in different forms of topsoil,increase the content of water stable aggregates and soil moisture storage,and reduce the soil bulk density of the surface layer.The comprehensive effect of the straw mulching method was the best.After straw mulching,compared to the control,the soil carbon storage management index increased by 55.00%,the annual cumulative runoff decreased by 61.27%,the output of soil decreased by 89.31%,and the output of total nitrogen and phosphorus decreased by 79.24%and 87.50%.At the same time,straw mulching can slightly increase the yield of citrus,significantly increase the sugar content of citrus,and reduce the content of titratable acid of citrus.In conclusion,mulching crops with straw between rows in low hilly orchards had a significant ecological effect,which can effectively reduce nutrient loss,improve soil physicochemical properties and ecological environment,and can serve as a maintenance measure for ecological optimization in southern hilly orchards.