摘要
坡度对地表水文、土壤侵蚀、土地利用规划有着重要的影响,区域尺度上的坡度通常基于数字高程模型(DEM)提取。区域尺度上,高分辨率坡度数据由于DEM获取途径、方式等原因,较难获得,通常通过超分辨率重构(又称降尺度变换)得到。以黄土高原地区水平梯田地形为研究对象,基于无人机摄影测量技术,生成不同分辨率的DEM数据并提取坡度,设计并给出了基于稀疏混合估计对DEM数据进行超分辨率重构的方法及流程,并与最近邻法、双线性插值法、三次卷积插值法比较,结果表明所提方法在空间分布和误差方面上均优于其他方法。
Slope is one of the key factors which had a close relationship with soil and water losses and land use planning,and it is one of the most important pieces of information in many natural source spatial databases. Slope was usually extracted from digital elevation model（ DEM） in regional scale. However,it is difficult to obtain DEMs with grid size less than 10-m from continental or country scale topographic maps that are needed to include topographic changes due to terraces because of manpower and financial restrictions. Thus the high resolution DEMs were usually obtained by super-resolution reconstruction or down scaling from low resolution DEMs. As a basic data source,high resolution DEMs created by superresolution methods do influence the extraction of slope. Dry terraced fields in the hilly loess region around Longquan of Yuzhong County were taken as study area. DEMs and orthophotos obtained in March,2015 by UAV-based photogrammetry were used. The resolution of the DEMs data was generated in 5 m,10 m,20 m and 40 m respectively for slope produce. Sparse mixed estimation method（ SME）,nearest method,bilinear method and cubic method were used for DEMs reconstruction. Finally,the slope was calculated from original DEMs and reconstructed DEMs. The result showed that the SME method was the best method in DEMs super resolution reconstruction for extraction of slope.
出处
《农业机械学报》
EI
CAS
CSCD
北大核心
2017年第1期112-118,138,共8页
Transactions of the Chinese Society for Agricultural Machinery
基金
国家自然科学基金项目(41301283
41371274
41301507)
陕西省自然科学基金项目(2015JM4142)
中央高校基本科研业务费专项资金项目(QN2013051
2013BSJJ105)
关键词
侵蚀
梯田
坡度
超分辨率重构
稀疏混合估计
erosion
terrace
slope
super-resolution reconstruction
sparse mixed estimation
