西南紫色土水蚀区坡谱信息熵与地形因子关系分析  

Relationship between slope spectrum’s information entropy and terrain factors in water erosion areas of purple soil in southwest China

作　　者：赵维军[1] 董奇群 燕婷婷 秦伟[3,4] 朱清科[2] Zhao Weijun;Dong Qiqun;Yan Tingting;Qin Wei;Zhu Qingke(Key Laboratory of Tourism and Resources Environment in Colleges and Universities of Shandong Province,Taishan University,Taian,271000,China;School of Soil and Water Conservation,Beijing Forestry University,Beijing 100083,China;State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin,China Institute of Water Resources and Hydropower Research,Beijing 100048,China;Research Center on Soil and Water Conservation of the Ministry of Water Resources,Beijing 100048,China)

机构地区：[1]泰山学院旅游与资源环境山东省高校重点实验室,泰安271000 [2]北京林业大学水土保持学院,北京100083 [3]中国水利水电科学研究院流域水循环模拟与调控国家重点实验室,北京100048 [4]水利部水土保持生态工程技术研究中心,北京100048

出　　处：《农业工程学报》2020年第9期160-167,F0004,共9页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金(41877073,41907050);中央基本科研业务费专项重点项目(SE0145B132017);山东省自然科学基金(ZR2019MD031);山东省高校科研计划项目(J18KA197)。

摘　　要：坡谱信息熵可综合反映地形起伏特征,计算便捷,为探索其能否替代计算繁杂的地形因子应用在土壤侵蚀评价中,该研究以西南紫色土水蚀区为研究对象,基于ASTER GDEM(30 m分辨率),计算坡谱信息熵、坡度坡长因子及沟壑密度等地形因子,分析坡谱信息熵与地形因子量化关系。结果表明:全区坡谱曲线形态有"S"、"L"及近似钟型,峰值集中分布在0°~3°、15°~18°、24°~27°;全区坡度坡长因子均值为11.03,空间北大南小的分布差异明显。区域尺度的沟壑密度为0.66km/km^2,流域尺度沟壑密度为0.33~0.88km/km^2;坡谱信息熵与坡度坡长因子在一级区(R^2=0.9494,P<0.01)、二级区(R^2=0.9603,P<0.01)均具有显著的对数或幂函数关系。与沟壑密度在川渝山地丘陵区呈显著的指数关系(R^2=0.7475,P<0.05),在其他区域尺度虽存在显著的多项式函数关系,但相关度较低。研究结果可为紫色土区水土流失评价、土壤侵蚀预报提供科学依据。In conventional soil erosion evaluation,the calculation of slope length and steepness(LS)factor requires the relatively complicated extraction of slope grade and slope length,and there are certain thresholds due to the determination of slope length to the location.Slope Spectrum’s Information Entropy(SSIE)can comprehensively represent the characteristics of topographic relief,but it is not clear that how to apply for the prediction of soil erosion.This paper aims to explore the relationship between the SSIE and topographic factors,while the research area is taking the water erosion area of purple soil in southwest China,including the Qinba mountains region,Wuling mountain hilly area,and Sichuan and Chongqing mountainous region.The slope gradient,slope length,and hydrographic net were extracted using ArcGIS based on ASTER GDEM(30 m resolution).After the calculation,two relationships were established between the SSIE and LS factor,as well the SSIE and gully density based on 63 basins.The results showed that:1)The whole region displayed the curves of slope spectrum in the shape of"L","S"and approximate bell,while the different curves of slope spectrum were successively distributed in Sichuan and Chongqing mountainous region,Wuling mountain hilly area and Qinba mountains region.Meanwhile,the main peaks of slope spectrum curves were concentrated in 0°-3°,15°-18°and 24°-27°.2)The mean of LS factor was 11.03,and the distribution range of LS factors was 0-5,10-15 and greater than 20 in Qinba mountainous region and Wuling mountain hilly area.However,that in Sichuan and Chongqing mountainous region was mainly concentrated in 0-15,showing obvious north-south difference.3)The gully density was 0.66km/km2 at the regional scale,particularly 0.72 km/km2 in Qinba mountains region,and 0.75 km/km2 in Wuling mountain hilly area.In Sichuan and Chongqing mountainous region,the gully density reached the minimum,0.57 km/km2,lower than 17.39%mean value of the regional scale.The gully density ranged from 0.33 to 0.88 km/km2 at th

关 键 词：地形 土壤侵蚀 坡谱信息熵 紫色土区 

分 类 号：S157.1[农业科学—土壤学]