【摘要】 文章从地面数据的调查、盐渍土影象的目视判读特征、光谱特征和土壤盐渍化区域的植被特征以及多光谱、高光谱遥感技术等方面综述国内外应用遥感数据探测土壤盐渍化程度及其制图的研究。利用数字图象并结合野外调查数据进行目视解译和计算机自动解译、图象变换提取盐渍土信息;结合G IS方法在分类中加入非遥感数据来提高分类精度;在研究盐渍土的光谱特征的基础上应用高光谱技术定量或半定量地提取盐渍土信息。这都是制定综合治理措施、决定土地利用方向的关键,也是进行区域土壤盐渍化动态预报的重要依据。更多还原

【Abstract】 Soil salinity is one of the major problems that affect crop growth and yield,and often lead to degradation of cultivated land.Recent advance in mapping and monitoring salt-affected soils by means of remote sensing has shown that this technology holds great promise in generating accurate results at enhanced speed and reduced cost.This paper first summarizes the role of ground data in detecting salt-affected soils,such as electrical conductivity of soils,underground water table,degree of mineralization,field-derived spectra of saline soils,and vegetation.In situ collected and laboratory data are very important in mapping and detecting salinity based on remote sensing technique.This paper then discusses the spectral properties of salt-affected soils,visual interpretation of saline features from remote sensing images,and use of vegetation as an indirect indicator.Key issues in and approaches of identification and mapping of salt-affected areas based on remote sensing technique are reviewed next.This review reveals that a multiplicity of remotely sensed data has been employed widely to investigate,identify,and monitor the surface salinity status of soils and its spatial distribution.The obtained results have demonstrated the value of spectral reflectance data for the calibration of remotely sensed data,ascertained the optimal bands in detecting salt-affected soils using spectra unmixing,established training range selection and mapping methods based on hyperspectral data for the validation of the quantitative information extracted from satellite data.These studies have used digital image interpretation,image transformation,hyperspectroscopy techniques in combination with GIS in order to map the distribution of salt-affected soils.Some studies have shown that hyperspectral remote sensing data have been applied to study soil salinity at an increasing pace.This technology carries great promise in producing more detailed and accurate soil salt information.更多还原