农业工程学报
農業工程學報
농업공정학보
2013年
13期
81-89
,共9页
郭明航%杨勤科※%王春梅
郭明航%楊勤科※%王春梅
곽명항%양근과※%왕춘매
土壤%侵蚀%地形%坡度%坡长%地形因子%LS因子
土壤%侵蝕%地形%坡度%坡長%地形因子%LS因子
토양%침식%지형%파도%파장%지형인자%LS인자
soils%erosion%topography%slope gradient%slope length%terrain factor%LS factor
地形是影响地表水文和土壤侵蚀的主要环境因素，坡度、坡长和 LS 因子是土壤侵蚀模型的重要参数。该文以第四次全国土壤侵蚀普查项目为依托，在ANUDEM软件环境中建立25m分辨率文地貌关系正确的DEM （Hydrologically Correct Digital Elevation Model, Hc-DEM），提取了坡度、坡长并计算了LS因子，对中国主要水蚀地区的土壤侵蚀地形因子的空间及统计特征进行了分析，并将该数据与目前应用较为广泛的2种遥感高程数据进行了对比。结果表明，25m分辨率Hc-DEM可用以表达各典型样区地形特征，其上提取的坡度和坡长，符合一般地貌学原理和常规认识；坡度在东北地区最为平缓（0.8°），而在黄土丘陵区最陡（22.3°）；坡长则在东北地区最长而黄土丘陵区最短（479m和69m）；在地势比较低的河谷和地势较高的分水地带坡度比较平缓，而在分水岭到河谷冲积平原之间坡度较陡；在地形起伏较大的陡坡丘陵或坡度平缓的丘陵，坡长均比较大；LS因子的空间分布格局与坡度基本一致；该文得到的数据与ASTER和SRTM遥感高程数据对比具有明显优势，全国土壤侵蚀普查项目建立的DEM，在全国、省区和大流域尺度上的土壤侵蚀评价制图中具有不可替代性。该文阐明了中国主要水蚀区的侵蚀地形特征，为土壤侵蚀学、水文学中地形因子的提取提供了参考。
地形是影響地錶水文和土壤侵蝕的主要環境因素，坡度、坡長和 LS 因子是土壤侵蝕模型的重要參數。該文以第四次全國土壤侵蝕普查項目為依託，在ANUDEM軟件環境中建立25m分辨率文地貌關繫正確的DEM （Hydrologically Correct Digital Elevation Model, Hc-DEM），提取瞭坡度、坡長併計算瞭LS因子，對中國主要水蝕地區的土壤侵蝕地形因子的空間及統計特徵進行瞭分析，併將該數據與目前應用較為廣汎的2種遙感高程數據進行瞭對比。結果錶明，25m分辨率Hc-DEM可用以錶達各典型樣區地形特徵，其上提取的坡度和坡長，符閤一般地貌學原理和常規認識；坡度在東北地區最為平緩（0.8°），而在黃土丘陵區最陡（22.3°）；坡長則在東北地區最長而黃土丘陵區最短（479m和69m）；在地勢比較低的河穀和地勢較高的分水地帶坡度比較平緩，而在分水嶺到河穀遲積平原之間坡度較陡；在地形起伏較大的陡坡丘陵或坡度平緩的丘陵，坡長均比較大；LS因子的空間分佈格跼與坡度基本一緻；該文得到的數據與ASTER和SRTM遙感高程數據對比具有明顯優勢，全國土壤侵蝕普查項目建立的DEM，在全國、省區和大流域呎度上的土壤侵蝕評價製圖中具有不可替代性。該文闡明瞭中國主要水蝕區的侵蝕地形特徵，為土壤侵蝕學、水文學中地形因子的提取提供瞭參攷。
지형시영향지표수문화토양침식적주요배경인소，파도、파장화 LS 인자시토양침식모형적중요삼수。해문이제사차전국토양침식보사항목위의탁，재ANUDEM연건배경중건립25m분변솔문지모관계정학적DEM （Hydrologically Correct Digital Elevation Model, Hc-DEM），제취료파도、파장병계산료LS인자，대중국주요수식지구적토양침식지형인자적공간급통계특정진행료분석，병장해수거여목전응용교위엄범적2충요감고정수거진행료대비。결과표명，25m분변솔Hc-DEM가용이표체각전형양구지형특정，기상제취적파도화파장，부합일반지모학원리화상규인식；파도재동북지구최위평완（0.8°），이재황토구릉구최두（22.3°）；파장칙재동북지구최장이황토구릉구최단（479m화69m）；재지세비교저적하곡화지세교고적분수지대파도비교평완，이재분수령도하곡충적평원지간파도교두；재지형기복교대적두파구릉혹파도평완적구릉，파장균비교대；LS인자적공간분포격국여파도기본일치；해문득도적수거여ASTER화SRTM요감고정수거대비구유명현우세，전국토양침식보사항목건립적DEM，재전국、성구화대류역척도상적토양침식평개제도중구유불가체대성。해문천명료중국주요수식구적침식지형특정，위토양침식학、수문학중지형인자적제취제공료삼고。
Terrain is one of the main environmental factors that influence ground water and soil erosion. Slope gradient, Slope length, and LS factor are important in soil erosion models. In this paper, DEM with a resolution of 25m was built in the software ANUDEM and slope, slope length, and LS factor were calculated with support from the fourth national soil erosion survey. Spatial and statistical characteristics for terrain factors that influence soil erosion were analyzed, and the result was contrasted with two kinds of remote sensing based elevation data that were used widely. The result showed that the typical terrain characters could be expressed by Hc-DEM with a resolution of 25m. Slope gradient and a slope length based on 25m Hc-DEM in accordance with the conventional understanding. Slope gradient was gentlest in the northeast region and steepest in the Loess Hilly region. Slope length was longest in the northeast region and shortest in the Loess Hilly region. Slope gradient was gentle in the bottom of valleys and ridge areas with higher elevation, and was steep in areas between the ridge and deposition areas. In areas with great relief steep hilly areas or gentle hilly areas, slope length was longer. The spatial distributions of LS factor were similar with that of the slope gradient. The data of this research was proven to be better than ASTER and SRTM elevation data. Moreover, the DEM data built in the fourth national soil erosion survey was irreplaceable in the field of soil erosion mapping at the national, province, and large watershed scales. This paper showed the characteristics of erosional terrain in the main water erosion region in China, and the result provided a basis for the calculation of terrain factors in research of soil erosion and hydrology.
