【摘要】 为缩短分析时间提高时效 ,建立了田间条件下土壤剖面硝态氮含量测定的方法 ,主要包括 1∶1土水质量比快速浸提土壤硝态氮 ,Merck反射仪进行浸提液硝态氮快速定量及酒精灼烧法快速测定土壤水分 ,根据土壤容重换算土壤硝态氮含量。将该方法与实验室常规的 0 0 1mol/LCaCl2 溶液 1∶10土水质量比浸提、连续流动分析法比较 ,结果表明 ,田间快速法与实验室常规法测定的土壤硝态氮含量具有极显著的相关性 ,2种方法测定表土层 (0～30cm)和底土层 (30～ 90cm)土壤硝态氮质量分数 (mg/kgN)的相关系数分别为 0 96和 0 92 ,按不同层次土壤容重换算表土层和底土层土壤硝态氮含量 (kg/hm2 N)的相关系数为 0 93和 0 92。更多还原

【Abstract】 It was difficult to use soil nitrate content in N fertilization recommendation because of long time of routine laboratory analysis. A quick method for analyzing soil nitrate content in field was developed. In this method, soil nitrate was extracted with distilled water (1∶1 of soil to distilled water). Nitrate concentration was measured by Merck Reflectance meter. Soil water content was measured by alcohol burning method. Nitrate concentration was also measured by routine method of 0.01mol/L CaCl 2 (1∶10 of soil to CaCl 2 solution) with continuous flow analysis (CFA). Soil water content was measured by oven drying method. A significant correlation was found between the soil nitrate concentration (mg/kg N) measured by the quick and the routine methods. The correlation coefficients in topsoil (0-30cm) and subsoil (30-60cm and 60-90cm) were 0.96 and 0.92 respectively. The correlation coefficient of the soil nitrate content (kg/hm2 N) in topsoil and subsoil were 0.93 and 0.92 respectively. The coefficient of variation were 0-8mg/hm2 and 0-18mg/hm2 N respectively.更多还原