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一、涝洼地土壤低产性状 1.土壤湿度大 涝洼地排水不良,土壤常呈过湿状态。由于它释水能力弱,雨水下渗缓慢,所以遇暴雨或连续降雨很容易造成涝灾。在淹水条件下产生的还原作用,不仅能淋失养料成分,而且会产生有毒物质。涝洼地土壤春季返浆永大,违农时,不易做到苗全、苗壮、苗齐;夏秋季节,雨水“坐堂”,影响铲、趟、中耕除草和割、拉、翻作业。 2.土壤温度低 涝洼地土壤含水量多,蒸发的多,所消耗的热量也多,所以土壤温度比疏干土壤的要低。涝洼地土壤冷浆、地温低,播种晚,
First, the low waterlogging depression of soil properties 1.Damp waterlogging depression drainage, soil often over-wet state. Because of its weak ability to release water, rain infiltration slow, so in case of heavy rainfall or continuous rainfall is very easy to cause floods. The reduction produced under flooded conditions not only leaches nutrients, but also produces toxic substances. Waterlogged depression soil spring back to the pulp is always large, against agriculture, it is not easy to achieve full seedling, seedling, Miao Qi; summer and autumn, the rain “sit down”, affecting shovel, trip, weeding and cut, pull, turn homework. 2. Soil temperature Low waterlogging depression of soil moisture content and more evaporation, also consume more calories, so the soil temperature is lower than the dry soil. Waterlogged depression soil cold slurry, low ground temperature, late sowing,