地表微地形测量及定量化方法研究综述

地表微地形测量是地表粗糙度定量化的基础，对地表形态动态监测、水文过程模拟以及土壤侵蚀过程模型的构建具有重要意义。目前，微地形测量方法主要分为接触式和非接触式2大类，前者包括测针法、链条法、差分GPS法等，后者包括超声波测距法、红外线传感器法、结构光激光扫描法、激光测距扫描法、三维激光扫描仪法、近景摄影测量法等。在全面回顾各方法原理、优缺点及其应用的基础上，分析地表粗糙度定量化常用方法：统计方法指数、地统计学指数和分形及多重分形模型。认为：1）差分GPS法、结构光激光扫描法、三维激光扫描仪法和近景摄影测量法将在亚毫米一，厘米级地表微地形测量及地表粗糙度多尺度特征研究中发挥重要作用，同时简单、方便的测针法可能在野外测量中依然占据主导地位；2）以地表微地形测量技术为基础，在土壤侵蚀过程模型中亟需形成一套完整的“测量一定量化一模型应用”范式，同时应加强对地表微地形空间异质性和各向异性的研究，发展新的统一的地表粗糙度定量化方法。

Review of measurement and quantification of surface microtopography

Surface microtopography, as the basis of quantification of surface roughness, is closely related to dynamic changes of soil erosion, hydrological process simulation and the soil erosion process modeling. At present, techniques used to quantify surface microtopography can be divided into two categories, contact and non-contact measurement. The former consists of pins, chain and GPS-RTK methods, while the latter includes ultrasonic, infrared sensor, structured lighting laser scanner, laser scanner based on distance measuring, 3D laser scanner and close -range photogrammetry. In first instance, a comprehensive review of the principle, merits and demerits and applications of all techniques is given in this paper. The next part is a brief introduction of often-used indices for water erosion research, which are based on statistical, geostatistical, fractal and multifractal models. Finally, two major conclusions are drawn. First of all, GPS-RTK, structured lighting laser scanner, 3D laser scanner and close-range photogrammetry will continually contribute to the measurement of microtopography at millimeter to centimeter scale and the research of muhiscale surface roughness characteristics, while the pins method will be still widely used in field test because of its simplification and convenience. However, based on the measurement techniques, more efforts should be made in generating an integrated technological process of measurement, quantification and model application in soil erosion models. Besides, by considering spatial anisotropy and heterogeneity of surface roughness, it is essential to develop a new and uniform quantification method for describing microtopography.