几种营养元素在土壤中的分布类型

The Distribution Type of Some Nutrient Elements in Soil

以方格法采取了红油土１４７个土壤样点，分别分析了其中铵态氮、硝态氮、Ｏｌｓｅｎ－Ｐ、氯离子、水溶性钾、钙、镁，并采用图检方法对这几种营养元素在土壤中的分布类型进行了研究，结果表明，土壤中的铵态氮，铵、硝态氮之和，Ｏｌｓｅｎ—Ｐ呈正态分布；Ｃａ２＋、Ｃａ２＋＋Ｍｇ２＋、Ｃｌ－也可用正态分布描述；硝态氮呈对数正态分布；Ｍｇ２＋既可用正态分布，也可用对数正态分布描述；Ｋ＋属偏态分布，其代表值只能用正态化后计算的平均值。根据分布类型分别计算了它们的统计值，并比较了采用何种统计值才能更好地反映土壤营养元素的含量。

One hundred and fourty seven soil samples were taken along two transects both from north to south and west to east with sampling points at an interval of 5 m in a Manured Loessial soil at the tilled depth (0 cm～25 cm), their NH + 4-N, NO - 3-N, Olsen-P, water soluble K +,Cl -,water soluble Ca 2+ and Mg 2+ analyzed, and their distribution types were iden tified by frequency histograms, normal probability diagrams, logarithmically normal probability diagrams and normalization diagrams. The results obtained show that ammonium-N, ammonium-N plus nitrate-N and Olsen-P belonged to normal distribution, and Ca 2+ ,Ca 2+ +Mg 2+ as well as Cl - could also be described by normal distribution while the nitrate-N belonged to logarithmically normal distribution. In contrast, Mg 2+ coul dbe described by either normal distribution or logarithmically normal distribution, and water soluble K + did belong neither to normal nor logarothmically normal distribution, but were obviously skewed. Based on their distribution type, the statistical values, particularly the means, were calculated, and a comparison was made among the means to indicate which statistical values were more suitable for reflecting the nutrient contents in the soil.