香根草植物篱地上-地下部分对三峡库区紫色土坡耕地氮素流失的影响  

Effects of Aboveground and Underground Parts of Vetiveria zizanioides L.Hedgerow on the Nitrogen Loss of Purple Soil on Slope Farmland in the Three Gorges Reservoir Area

作　　者：郭萍[1,2,3] 夏振尧 张伦[1] 向瑞 张文琪 朱志恩 肖海 杨悦舒 GUO Ping;XIA Zhenyao;ZHANG Lun;XIANG Rui;ZHANG Wenqi;ZHU Zhien;XIAO Hai;YANG Yueshu(Key Laboratory of Geological Hazards on Three Gorges Reservoir Area,Ministry of Education,Yichang 443002,China;College of Civil Engineering&Architecture,China Three Gorges University,Yichang 443002,China;School of Architecture and Civil Engineering,Huizhou University,Huizhou 516007,China)

机构地区：[1]三峡库区地质灾害教育部重点实验室,湖北宜昌443002 [2]三峡大学土木与建筑学院,湖北宜昌443002 [3]惠州学院建筑与土木工程学院,广东惠州516007

出　　处：《应用基础与工程科学学报》2023年第4期852-864,共13页Journal of Basic Science and Engineering

基　　金：国家自然科学基金项目(U2040207,42277323,41807068)。

摘　　要：植物篱能影响坡面产流产沙过程,进而影响其携带的氮素流失,但植物篱地上及地下部分对氮素流失的影响尚不明确.通过设置1个降雨强度(60mm/h)、2个坡度(15°和25°)和3个坡面条件(裸坡对照、植物篱和仅有植物篱根系),开展人工降雨试验,分析坡面侵蚀量和径流量及其携带的硝态氮(NO-3-N)、氨态氮(NH+4-N)和全氮(TN)含量与流失量的变化特征.结果表明:植物篱可以减少坡面侵蚀量和径流量的产生,坡面土壤氮素主要以泥沙为载体而流失;植物篱可以降低坡面径流携带的氮素含量却增加了侵蚀泥沙中氮素含量,并能够有效地减少坡面径流和泥沙所携带氮素流失量;植物篱通过地上部分和地下部分共同发挥作用减少坡面氮素流失量,其中地上部分和地下部分对减少坡面NO-3-N、NH+4-N、TN流失量的平均贡献率分别为43.97%和56.03%、44.12%和55.88%、46.91%和53.09%.以上结果加深了香根草植物篱对坡耕地氮素流失影响机理的理解,可为三峡库区坡耕地水土资源可持续高效利用提供科学依据.Hedgerow can influence not only on the erosion and runoff process,but also on the related nitrogen loss on slope farmland.However,the effect of aboveground part and underground part of hedgerow on nitrogen loss is still not clear.Simulated rainfall experiments were conducted at 1 rainfall intensity(60mm/h),2 slope gradients(15°and 25°)and 3 slope conditions(Control check,Hedgerow and Only hedgerow roots)to analysis the sediment amount,runoff amount,and the content and loss of nitrate nitrogen(NO-3-N),ammonia nitrogen(NH+4-N)and total nitrogen(TN)via them.The results indicated that the hedgerow could effectively reduce the sediment amount and runoff amount,and the nutrient was mainly lost via sediment.The nitrogen content in runoff could be reduced by hedgerow while that could be increased in sediment,and finally the hedgerow could effectively reduce the nutrient via both runoff and sediment.The reduction effect can attribute to the combination of aboveground and underground parts of hedgerow,and the average contribution rates of aboveground part and underground part of hedgerow to the reduction of nutrient loss amount for NO-3-N,NH+4-N,TN were 43.97%and 56.03%,44.12%and 55.88%,46.91%and 53.09%,respectively.The results could deepen the understanding of the influence mechanism of Vetiveria zizanioides hedgerow on nitrogen loss of slope farmland,and provide a scientific basis for the sustainable and efficient utilization of soil and water resources of slope farmland in the TGRA.

关 键 词：三峡库区 植物篱 氮素流失 地上部分 地下部分 贡献率 

分 类 号：S157.1[农业科学—土壤学]