岔口小流域AnnAGNPS模型参数敏感性分析  

Sensitivity Analysis of AnnAGNPS Model Parameters in Chakou Watershed

作　　者：娄永才 郭青霞[1] LOU Yong-cai;GUO Qing-xia(College of Resources and Environment,Shanxi Agricultural University,Taigu 030801,China)

机构地区：[1]山西农业大学资源环境学院,山西太谷030801

出　　处：《生态与农村环境学报》2018年第3期207-215,共9页Journal of Ecology and Rural Environment

基　　金：国家自然科学基金(41071345)

摘　　要：以黄土丘陵沟壑区岔口小流域为例,选取可能对农业非点源污染模型Ann AGNPS产生影响的径流曲线数CN值、降雨侵蚀因子、饱和导水率、田间持水量、耕作管理因子、水土保持因子、土壤侵蚀因子、地形因子、沟道曼宁系数和化肥施用量等10个因子,采用修正的摩尔斯(Morris)分类筛选法,分析影响模型模拟结果的敏感性程度,在此基础上对模型进行模拟验证。结果表明:CN值与模型模拟结果呈明显正相关;沟道曼宁系数和田间持水量与模型输出结果均呈明显负相关;影响地表径流量输出最敏感的参数是CN值和田间持水量;影响模型泥沙、营养盐输出最敏感的参数主要是CN值、土壤可蚀性因子、耕作管理因子、地形因子和水土保持因子;氮磷污染物空间分布不具一致性,区域差异明显,土壤氮磷库是其流失主要来源;径流模拟结果显示R2和Ens均为0.99,模型能较好地反映流域地表径流过程;泥沙和氮磷模拟误差较大,但在一定程度上能反映流域水土流失及氮磷污染的趋势,对流域水土流失及非点源污染的治理具有一定的参考价值。Chakou Watershed was located in the typical loess hilly-gully region,and was selected as study area.Ten parameters of AnnAGNPS model were selected for sensitivity analysis,and Morris classification method was used to analyze the sensitivity of the parameters to the simulation results of the model.Based on the results of parameter sensitivity analysis,the model calculation results were verified.The results show that:The number of runoff curves has great positive influence on model output;Channel Manning coefficient and field water-holding capacity have negative influence on model output.The most sensitive parameters affecting the surface runoff output are the number of runoff curves and the field water-holding capacity.The most sensitive parameters affecting the sediment and nutrient output are the number of runoff curves,soil erodibility factor,tillage management factor,topographic factor,and soil and water conservation factor.The spatial distribution of nitrogen and phosphorus pollutants is not consistent,the regional differences are obvious,and the soil nitrogen and phosphorus pools are the main sources of their losses.The model can better reflect the surface runoff process(R 2=0.99,Ens=0.99).The results of simulations on sediment,nitrogen and phosphorus are widely inaccurate,but to some extent,it can reflect the trend of soil and water loss and nitrogen and phosphorus pollution,and has certain reference value to the control and management of soil erosion and non-point source pollution.

关 键 词：ANNAGNPS 参数敏感性 摩尔斯 岔口小流域 

分 类 号：X32[环境科学与工程—环境工程] X52