Regionalization of Salt-affected Land for Amelioration in the Yellow River Delta Based on GIS
GUAN Yuan xiu, LIU Gao huan, WANG Jin feng (The State Key Laboratory of Resources and Environment Information System, Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China)
Soil salinization is the major land degradation problem and has seriously influenced the sustainablal agricultural development. Regionalization of salt affected land is the precondition for effective amelioration. The present saline land situation is obtained by remote sensing image processing. The cause that leads to land salinization is analysized. Especially, the two key factors, ground water depth and mineralization degree that control land salinization, are analysized by using long term observation data. Previously, regionalization of saline soil was done descriptively and artificially. Based on the present saline land situation, ground water depth and ground water mineralization degree, the regionalization of saline land for amelioration in the Yellow River Delta is done quantitatively. Four different saline land amelioration regions are delineated, namely, easy amelioration region, relatively difficult amelioration region, difficult amelioration region and unfavorable amelioration region. Countermeasures for ameliorating saline soils are put forward according to ecological conditions of different saline land regions. This not only greatly improves regionalization speed but also accuracy.