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土壤盐渍化是松嫩平原存在的主要生态环境问题之一。在年降水量基本保持稳定波动的情况下,松嫩平原西部河流年径流量逐年衰减,自然泡沼和湿地面积日益缩小,区域地下水位普遍呈持续下降趋势。与此同时盐渍化土壤面积却显著增加,特别在低平原地区土壤盐渍化呈扩大和加重态势。土壤原生盐渍化和次生盐渍化过程分析表明:目前松嫩平原发生的土壤次生盐渍化应主要归因于人类的经济活动改变了原来内流区地表的水文过程,极大地减少了地表积水-径流的数量和时间。土壤原生苏打盐渍化是在浅埋深地下水和地面渍涝积水的共同作用下形成的,浅埋深地下水是土壤表层积盐的主要原因,而地面渍涝积水使土壤表层积累的盐分向微地貌的高处迁移,影响了苏打盐渍土在地表的分布格局。在土壤开始发生盐渍化的阶段,浅埋深地下水起了很重要的作用;随着土壤盐渍化程度的加重,地下水盐分向土壤迁移量越来越少;在目前次生盐渍化阶段,地下水对土壤盐渍化作用微弱,甚至可以忽略。
Soil salinization is one of the major ecological and environmental problems in the Songnen Plain. Under the condition of stable annual precipitation, the annual runoff of western Songnen Plain declines year by year, and the area of natural marshland and wetland shrinks day by day. The groundwater table in the area tends to decline continuously. At the same time, the area of salinized soils increased significantly, especially in the low-lying areas, the salinization of soil increased and aggravated. Soil salinization and secondary salinization process analysis shows that the current secondary salinization of soil in the Songnen Plain should be mainly attributed to the fact that the economic activities of mankind have changed the hydrological processes on the surface of the original inflow area and greatly reduced Surface water accumulation - the amount and time of runoff. Soil primary soda salinization is formed under the combined effect of shallow depth groundwater and groundwaterlogging waterlogging. Shallow depth groundwater is the main reason for surface salt accumulation in the soil, while surface waterlogging and waterlogging make salt accumulation in the soil surface The migration to the top of micro-topography affected the distribution pattern of sodic saline soil on the surface. In the stage of soil salinization, shallow groundwater plays a very important role. With the degree of soil salinization increasing, the migration of groundwater salinity to the soil is less and less. In the current secondary salinization stage Groundwater salinization of the soil weak, or even negligible.