基于改进型DNDC模型的小流域非点源氮迁移过程模拟与空间拓展应用  

Simulation of nonpoint source nitrogen transport in two separated catchments in the hilly area of purple soil

作　　者：杨小林[1,2] 朱波[3] 李义玲[1] 花可可[2] 

机构地区：[1]河南理工大学 安全应急管理研究中心 [2]中国科学院 成都山地灾害与环境研究所,四川成都610041 [3]中国科学院成都山地灾害与环境研究所,四川成都610041

出　　处：《水利学报》2013年第10期1197-1203,共7页Journal of Hydraulic Engineering

基　　金：国家重点基础研究发展计划(2012CB417101)

摘　　要：以长江上游紫色土区截流堰小流域和大兴小流域为研究对象,应用改进型DNDC(Enhanced Denitrification Decomposition Model)模型对紫色土区小流域径流、泥沙和氮流失过程进行模拟研究。采用截流堰小流域2007—2009年和2010—2011年径流、泥沙及氮迁移监测数据分别进行模型参数率定和验证,检验模型在紫色土区的适用性,然后利用大兴小流域2011年水文、水质监测数据对该模型进行拓展验证,探讨模型在具相似空间结构特征的小流域尺度拓展的可行性。结果显示:率定期和验证期月径流、土壤侵蚀、氮流失Nash-Sutcliffe效率系数大多超过0.80,相对误差均在16.36%以内。拓展验证期,月径流、土壤侵蚀、总氮(TN)和颗粒态氮(PN)的NashSutcliffe效率系数分别为0.70、0.55、0.76和0.71,相对误差分别为6.2%、31.2%、9.5%和30.4%。改进型DNDC模型能较好模拟紫色土区小流域径流、泥沙和氮迁移过程,但尺度拓展过程中泥沙、颗粒态氮的模拟偏差有所增大。In this study, a hydrology-biogeochemistry-based （enhanced DNDC model） model was employed to simulate the water quantity and water quality in two separate but similar watersheds in the hilly area of purple soil. The enhanced DNDC model was calibrated with data in a period of 36 months （2007-2009） and validated with data of 24 months period （2010-2011） in Jieliuyan watershed, and extended validated with data of 12 months period （2011） in Daxing watershed. The primary objective of this study was to com- pare hydrology, sediment and nitrogen simulation results in two separate, but similar, watersheds. The simu- lation results of monthly discharge, sediment and nitrogen show that the enhanced DNDC model performed satisfactorily in the study area （Ens--0.90, 0.92, 0.89, and 0.88 in calibration period and Ens=0.83, 0.87, 0.74, and 0.52 in validation period for discharge, sediment yield, total nitrogen and particulate nitrogen, respectively）. The results indicate that the enhanced DNDC model is an appropriate model for the non-point source nitrogen pollution simulations in purple soil area. The possibility of extended validation has been proved due to the encouraging results during the extended validation period. However, lower Ens and larger Ro for sediment yield and particulate nitrogen were observed in the extended validation period in a larger watershed due to the model weakness of channel nrocess.

关 键 词：紫色土区 改进型DNDC模型 率定和验证 相似小流域 拓展验证 

分 类 号：X522[环境科学与工程—环境工程]