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世界上影响灌溉农业最大的问题是盐渍化问题。中国是受土壤盐渍化影响的大国。盐碱化曾是限制封丘县农业生产的四大自然灾害之一。本文基于40个土壤剖面数据,结合第二次土壤普查的盐土数据,对封丘县的土壤盐分的时空特征进行了系统研究。结果表明:27年来封丘县土壤盐分含量大幅下降,盐碱土作为土壤发生类型只存在于极个别微域景观;土壤含盐量较高的区域集中分布在东南部,与地下水埋深趋势相吻合,但只有东南角部分地区含盐量超过0.293dS/m为盐化土。地下水位下降是土壤盐分降低的主要原因。盐分聚集在40cm以下,并未脱离土体。封丘县存在土壤盐碱化的自然条件,一旦水文地质条件发生变化,土壤盐渍化仍然可能发生。
The biggest problem affecting irrigated agriculture in the world is salinization. China is a big country affected by soil salinization. Salinization was one of the four major natural disasters that limited the agricultural production in Fengqiu County. Based on the data of 40 soil profiles and the saline soil data of the second soil survey, the spatial and temporal characteristics of soil salinity in Fengqiu County were systematically studied. The results showed that the soil salinity content of Fengqiu County dropped drastically in the past 27 years. Saline-alkaline soil existed only as a kind of soil micro-area landscape in the past 27 years. The areas with high salt content in the soil were concentrated in the southeast, which accorded with the trend of groundwater depth , But only the salinity in some parts of the southeast corner exceeded 0.293dS / m as salinized soil. The decrease of groundwater level is the main reason for the decrease of soil salinity. Salt accumulation below 40cm, did not break away from the soil. Fengqiu County has the natural conditions of soil salinization. Once the hydrogeological conditions have changed, soil salinization may still occur.