【摘要】 本文用荷兰8种表土测试不同温度下0.01molL^-1CaCl₂提取液和淋滤液中N素各形态。试验结果表明温度对NO₃^--N提取量和淋滤量无影响,但对NH₄⁺-N、可溶性总N和还原态N影响显著;可溶性有机态N的释放服从一级动力学方程:N_t=N₀(1-e^-kt),非线性最小二乘法能满意地拟合动力学实验结果。测定0.01molL^-1CaCl₂提取液中的可溶性有机态N对预测土壤N素矿化、合理推荐施肥及防止N素污染可能是一个很有前途的指标。更多还原

【Abstract】 Eight Dutch surface soils were used in this study to analyse different N fractions in 0.01 molL^-1 CaCl₂ extracts and percolates at different temperatures.The resulcs obtained showed that:（1） The temperature of 0.01 molL^-1 CaCl₂ extracting and percolating solution had no influence on amount of No₃^- -N,the extractability of other N fractions （NH₄⁺ -N,total soluble N and reduced N）,however,was evidently affected by the temperature in 0.01 molL^-1 CaCl₂ solution.The hydrolysis of organic N was the predominant reason for this influence.（2） The release of organic soluble N obeyed the first order kinetics.A nonlinear least square method could bestfit the experimental data into the model N_t=N₀(1——e^-kt)with Rsquared being higher than 0.99.（3） The kinetic values No were highly consistent with the soluble reduced N in extraction experiment.The 0.01 molL^-1 CaCl₂ solution extracted and released the labile organic N fraction.The determination of soluble org anic N in 0.01 molL^-1 CaCl₂ solution looked promising as a property for prediction of N mineralization,N fertilization and N pollution.更多还原