基于不同流向算法的地形湿度指数模型差异性分析  

Research on the Differences in Terrain Humidity Index(THI)Models Based on Different Flow-Direction Algorithms

作　　者：唐瀑漾 罗明良[1,2] 白雷超 刘晋红 Tang Baoyang;Luo Mingiang;Bai Leichao;Liu Jinhong(School of Geographical Sciences,China West Normal University,Nanchong 637009;Jialing River Basin Research Institute,China West Normal University,Nanchong 637009)

机构地区：[1]西华师范大学地理科学学院,四川南充637009 [2]西华师范大学嘉陵江流域研究所,四川南充637009

出　　处：《中阿科技论坛（中英文）》2024年第3期99-103,共5页China-Arab States Science and Technology Forum

基　　金：国家自然科学基金项目(41871324)。

摘　　要：土壤侵蚀是全球性的主要环境问题之一,不但会导致土壤退化、土地生产力降低和耕地面积减少,直接影响农业生产的食品安全,而且随径流泥沙转移对异地生态环境带来严重的影响。文章选取冬季云南元谋秃秃脊梁子地区的侵蚀沟区作为研究对象,基于高精度无人机航摄所得的数字高程模型(DEM),利用4种流向算法(Rho8、D8、Dinf和MFD-md)得到地形湿度指数(TWI)在3种分辨率下的运算结果,分析不同流向算法的地形湿度指数模型的差异性。研究结果表明:不同流向算法的差异主要集中在侵蚀沟坡面细沟区域;单流向算法可以有效展示沟道坡面细沟,多流向算法可以展示研究区整体汇水趋势;分辨率越高,算法的差异会越明显。文章进一步指出地形湿度指数对流向算法、DEM分辨率参数具有强烈的依赖性。As one of the major global environmental problems,soil erosion led to soil degradation,undermined land productivity and reduced arable land,which not only posed great threat to agri-food security,but also exerted severe impact on off-site ecological environment due to the influx of runoff sediment.In response to this,the article selects the erosion ditch in Yuanmou,Yunnan Province as the research subject.Based on the digital elevation model obtained from high-precision UAV aerial photography,this thesis applies four flow-direction algorithms(Rho8,D8,Dinf,and MFD md)to obtain the calculation results of TWI at three resolutions,In order to analyze the differences in TWI of different algorithms.The research findings indicate that the differences are mainly concentrated in the regions of rills on the slope surface;The single-flow algorithm is more effective in displaying the rills,while the multi-flow algorithm is more fit for displaying the overall trend of catchment;and the higher the resolution,the more significant the differences will be.To this end,it should be noted that the THI has a strong dependence on the flow-direction algorithm and DEM resolution parameters.

关 键 词：地形湿度指数 流向算法 DEM分辨率 模型差异性 

分 类 号：S157[农业科学—土壤学]