SWAT模型最佳子流域划分方案研究——以云南洱海流域为例  

Study on Optimal Sub-division Scheme of Watershed Using SWAT Model——A Case Study in Erhai Basin,Yunnan Province

作　　者：李曼曼[1,2] 韩会玲[1] 刘晓英[2] 郝卫平[2] 

机构地区：[1]河北农业大学城乡建设学院,保定071000 [2]中国农业科学院农业环境与可持续发展研究所/农业部旱作节水农业重点实验室,北京100081

出　　处：《中国农业气象》2012年第2期185-189,共5页Chinese Journal of Agrometeorology

基　　金：国际科技合作项目(2010DFB30550);948引进项目(2011-G9);国家863项目(2011AA100501);中央级公益性项目(BSRF201107);国家科技支撑计划项目(2012BAD09B01)

摘　　要：应用SWAT模型(Soil and Water Assessment Tool),以区域气候复杂的云南省洱海流域为例,研究不同子流域划分数量对径流和泥沙负荷模拟结果的影响,以明确洱海流域合理的子流域划分方案。结果表明,随着子流域划分数量的增加,年均径流深增加但敏感性较小,相对偏差仅0.89%;年均泥沙负荷减少而敏感性较大,相对偏差达21.21%。经综合权衡年均径流和泥沙负荷对子流域划分响应的敏感性,提出洱海流域合理的子流域划分临界值为137个,相应子流域平均面积占流域总面积的0.73%。在大于该临界值的划分水平下,模拟的年均径流深和泥沙负荷趋于稳定,但对进一步提高模拟精度无明显效果。研究结果对其它地形地貌复杂的流域水文模拟和非点源污染模拟具有重要借鉴意义。Taking Erhai basin, Yunnan province as an example, this paper investigated the effect of sub-division level on simulations of runoff and sediment load under SWAT （ Soil and Water Assessment Tool） framework, and determined the optimal sub-division scheme. Results showed that the annual average runoff depth increased with the number of the sub-watershed, but the sensitivity was relatively small, and the relative deviation was only 0.89%. In contrast, the annu- al average sediment load decreased with the number of the sub-watershed, and the sensitivity was relatively large, the relative deviation being 21.21%. Considering the response of both the annual average runoff depth and sediment load to the sub-division scheme, a threshold value of 137 was proposed as the optimal sub-division level in Erhai basin, and the average area of the sub-watershed accounts for 0.73 % of the total basin area. Above this critical value, the simula- ted runoff depth and sediment load were stabilized, and their accuracy could not be improved further. According to our results, the method, using ratio of a sub-watershed to total basin area to determine the optimal number of sub-water- shed in previous studies, cannot describe the real condition in a basin. Our results have implication for hydrological simulations and non-point source pollution simulations in other similar complex topographical watershed.

关 键 词：SWAT模型 洱海流域 子流域划分 

分 类 号：S271[农业科学—农业水土工程]