农业机械学报2017，Vol.48Issue(10)：172-179,8.DOI:10.6041/j.issn.1000-1298.2017.10.021
梯田区侵蚀地形因子随DEM分辨率变化的特征分析
Analysis of DEM Resolution on Erosional Terrain Characteristics of Terrace Area
摘要
Abstract
Terrain is a main environmental factor which affects the surface hydrology and soil erosion.Slope steepness,slope length and LS factor are important parameters in soil erosion.model.As a water conservation measure,terraced field changes the surface morphology and affects slope steepness,slope length and LS factor.Terrain features of the terraced area based on low resolution DEM are fuzzy and difficult to be reasonably estimated due to the lacking of high precision.High resolution DEM,which was accessed by UAV aerial photogrammetry technology,was used to analyze slope steepness,slope length and LS factor under different resolutions.Meanwhile,the changes of these parameters were calculated and analyzed in a none terraced area with the same resolution changes as comparison.The result showed that the DEMs which were accessed by UAV can express the terrace terrain features in details.Distribution of terraced terrain factors coincided with topographic features.These features showed high values distributed in the ridge area and small values distributed in terrace surface.With the decrease of DEM resolutions,the slope steepness of none terraced areas was decreased while the slope length was increased,and LS value was increased firstly and then decreased because of the fast decrease of the slope stcepness,but the variation range was relatively small.For terraced areas,the portion of both small and large part of the slope steepness was decreased,average slope steepness was also decreased.Slope length had a clear increasing trend,so as the LS factor.Under the resolution of 20 m,LS factor was overestimated for about 33％.Terracing is usually considered as a project factor in soil erosion models of soil and water conservation measures.Due to the large influence of resolution on LS factors,the estimation of erosion in terraced field needs to consider the effect of resolution changes.关键词
土壤侵蚀/中国水土流失方程/地形因子/梯田/数字高程模型Key words
soil erosion/Chinese soil loss equation/topographic factor/terrace/DEM分类
农业科技引用本文复制引用
张宏鸣,杨勤科,王猛,杨江涛,王美丽,晋蓓..梯田区侵蚀地形因子随DEM分辨率变化的特征分析[J].农业机械学报,2017,48(10):172-179,8.基金项目
国家重点研发计划项目(2017YFC0403203)、国家自然科学基金项目(41771315、41301283、41371274、41301507、61402374)、欧盟地平线2020研究与创新计划项目(ISQAPER:635750)、陕西省自然科学基础研究计划项目(2016JM6038)和西北农林科技大学基本科研业务费专项资金项目(2452015060) （2017YFC0403203）
