8种土壤126个氮素解吸实验表明,解吸模型C=ClH-a能模拟土壤铵态氮、硝态氮的解吸动态规律,其中有125个实验的复相关系数达到极显著水平。盆栽试验和田间试验结果表明,对生长期较短的空心菜、菜心和莴苣而言,土壤氮素可解吸量Q和土壤溶液氮素初始浓度C li与供试蔬菜的氮素吸收量和产量之间有显著的抛物线型关系,为评价土壤氮素生物有效性和临界指标提供了一种新方法。 126 nitrogen desorption experiments on eight soils showed that the desorption model C = ClH-a could simulate the dynamic laws of soil ammonium nitrogen and nitrate nitrogen desorption, and the correlation coefficients of 125 experiments reached extremely significant levels. The results of pot experiment and field experiment showed that for the shorter growth period of cabbage, cabbage and lettuce, the soil nitrogen desorption Q and the soil nitrogen initial concentration C li and the nitrogen absorption and yield of the tested vegetables There is a significant parabolic relationship between soil nitrogen and soil, which provides a new method for evaluating the bioavailability and critical index of soil nitrogen.