淮北地区生土农田养分平衡与土壤肥力变化的关系

SOIL FERTILITY CHANGE AS AFFECTED BY NUTRIENT BALANCES IN NEWLY LEVELED FARMLAND

在江苏淮北地区土地平整后形成的生土上,对水稻小麦水稻、水稻油菜水稻、水稻绿肥水稻3种种植模式不同施肥条件下的氮、磷、钾产投比及与土壤肥力关系进行试验分析.结果表明:随着种植季数的增加,氮、磷的产投比有很大的提高.3季种植后,有机质投入量与土壤有机质净增量,总投氮与土壤全氮、碱解氮,总投磷量与土壤速效磷,总投钾量与速效钾均呈显著正相关,肥料投入对生土土壤肥力演变起决定性作用.

An experiment was conducted in the seashore region of northern Jiangsu to probe the causality of fertility enhancement of the immature soil formed after land leveling with application of some organic manures such as pig manure, cake manure and straws. The result showed that the nutrient output/input ratios increased with the number of cropping seasons on the immature soil. There were significant positive correlations between the contents of soil organic matter and the amount of applied organic material to the soil. The contents of soil total N, available N, available P and available K were also positive correlative with respective nutrient inputs into the soil and with respective nutrient differences between the input and output. It was concluded that inputs of organic material and nutrients were the key factors that controled the fertility evolution of the immature soil.