Wang Tao, He Fuhong, Zhang Anding, Gu Lijuan, Wen Yangmao, Jiang Weiguo, Shao Hongbo
College of Geography and Planning, Ludong University, Yantai 264025, China.
College of Geography and Planning, Ludong University, Yantai 264025, China ; Shandong Provincial Key Laboratory of Soil Conservation and Environmental Protection, Linyi 276000, China.
ScientificWorldJournal. 2014 Jan 29;2014:417325. doi: 10.1155/2014/417325. eCollection 2014.
This paper took a subregion in a small watershed gully system at Beiyanzikou catchment of Qixia, China, as a study and, using object-orientated image analysis (OBIA), extracted shoulder line of gullies from high spatial resolution digital orthophoto map (DOM) aerial photographs. Next, it proposed an accuracy assessment method based on the adjacent distance between the boundary classified by remote sensing and points measured by RTK-GPS along the shoulder line of gullies. Finally, the original surface was fitted using linear regression in accordance with the elevation of two extracted edges of experimental gullies, named Gully 1 and Gully 2, and the erosion volume was calculated. The results indicate that OBIA can effectively extract information of gullies; average range difference between points field measured along the edge of gullies and classified boundary is 0.3166 m, with variance of 0.2116 m. The erosion area and volume of two gullies are 2141.6250 m(2), 5074.1790 m(3) and 1316.1250 m(2), 1591.5784 m(3), respectively. The results of the study provide a new method for the quantitative study of small gully erosion.
本文以中国栖霞北岩子口流域小流域沟谷系统中的一个子区域为研究对象，采用面向对象图像分析（OBIA）方法，从高空间分辨率数字正射影像图（DOM）航空照片中提取沟谷的谷肩线。接着，提出了一种基于遥感分类边界与沿沟谷谷肩线的RTK - GPS测量点之间的相邻距离的精度评估方法。最后，根据提取的实验性沟谷Gully 1和Gully 2的两条边缘的高程，采用线性回归拟合原始地表，并计算侵蚀量。结果表明，OBIA能够有效提取沟谷信息；沿沟谷边缘实测点与分类边界之间的平均距离差为0.3166 m，方差为0.2116 m。两条沟谷的侵蚀面积和侵蚀量分别为2141.6250 m²、5,074.1790 m³和1316.1250 m²、1,591.5784 m³。研究结果为小沟谷侵蚀的定量研究提供了一种新方法。
