摘要
From the analysis on the problem of selection, data acquisition, quantification and accuracy check in the indicators to desertification degree both at home and abroad, one might conclude that in the existing assessment of desertification degree there is a prevailing tendency which is the substitution of absolute landscape for relative land degradation, namely, assessment of desertification degree is that of absolute landscape state to some extent. As a result the reassessment accuracy of desertification scope, damaging degree and control effect are affected. The regaining and establishment of the initial and final ecological datum level of land degradation are the prerequisite to the establishment of normal scientific indicator system. From the viewpoint of this three design principles of indicators to the desertification degree are put forward: the zonal principle of indicator systems decided by the ecological datum level corresponding to their bioclimatic zones, the hierarchical principle of indicator systems decided by different spatial scales and the resolutions of different sensors and principle of landscape types based on the 3S as core-indicator.
From the analysis on the problem of selection, data acquisition, quantification and accuracy check in the indicators to desertification degree both at home and abroad, one might conclude that in the existing assessment of desertification degree there is a prevailing tendency which is the substitution of absolute landscape for relative land degradation, namely, assessment of desertification degree is that of absolute landscape state to some extent. As a result the reassessment accuracy of desertification scope, damaging degree and control effect are affected. The regaining and establishment of the initial and final ecological datum level of land degradation are the prerequisite to the establishment of normal scientific indicator system. From the viewpoint of this three design principles of indicators to the desertification degree are put forward: the zonal principle of indicator systems decided by the ecological datum level corresponding to their bioclimatic zones, the hierarchical principle of indicator systems decided by different spatial scales and the resolutions of different sensors and principle of landscape types based on the 3S as core-indicator.
基金
Under the auspices of the National Natural Science Foundation of China (49771009) and the Guangdong Provincial Key Research Proj