Studies on soil desiccation of croplands in cinnamon soil region of Shanxi
论山西褐土区农田土壤干燥化问题

This article, taking corn and wheat fields in Lishi, Xinzhou, Taiyuan, Shouyang, Linyi as examples, selects five representative 0~600cm deep soils (some are 700cm deep) separately from 12 profiles to analyze soil moisture situation in different seasons and different vertical profiles.The research obtains: The dry layer of soil in the Loess Plateau regionexists universally in corn and wheat fields of the study area, presenting both in mild and moderate dry layers.The characteristic of seasonal dry layer is the main cause that makes crops in the region liable to be hit by drought. The mild dry layer in Jinzhong exists in soils below 600cm. The long-term drought in southern Shanxi; aggravates desiccation degree, the dryness of mild soil has also developed to 600cm. The dry layer of soil in 400cm in western Shanxi tends to be mild. The dry soil layer in northern Shanxi reaches 600cm, indicating a mild dryness there. The occurrence of seasonal dry layer and deep soil dryness of farmland seriously affects the farmland soil water circulation. The main reason that causes the natural phenomenon of the development of dry layer of the local farmland is scarce precipitation,but the formation of temporary dry layer due to increase of productivity, vegetation density and evaporation have also exerted noticeable influence. To mitigate farmland dryness the effective ways are to select low-water consumption dryland crops, and to practise rational close planting, and irrigation in places where condition are permitted.