东南地区土壤养分的空间变异性与取样策略Ⅱ.中微量元素

Spatial Variability and Sampling Strategy of Soil Nutrient in Southeast China Ⅱ.Secondary and Micro-elements

在我国东南5省选择6个代表性区域(自然村),采用ASI和地统计学等方法对耕作土壤的有效Ca、Mg、S和Zn的空间变异性与合理取样数量进行了研究。结果表明,①中微量元素的一般变异性大小顺序为:S>Zn>Mg>Ca,有效Ca和Mg的变异主要受土壤母质和微地形等区域性因素的影响,有效Zn的变异主要与作物布局和施肥水平等随机性因素有关,有效S的变异则同时受水分条件、作物布局和施肥水平的制约;②尽管某些中微量元素的总体变异性相似,但在各研究区域,其实际半方差结构并不相同;③对于明显偏斜的土壤养分来说,建议采用最适分配法确定合理取样数量,纯随机合理取样数量仍可作为重要参考。

Based on the data from 6 natural villages of 5 provinces in southeast China, the spatial variability and rational sampling strategy of soil available Ca, Mn, S and Zn was studied using ASI method and Geo-statistics. Results showed that： （1）The general variability of soil secondary and micro-elements was graded as S〉Zn〉Mg〉Ca. The spatial variability of Ca and Mg was mainly influenced by regional factors, such as parent material and micro terrain. The spatial variability of Zn was mainly influenced by random factors, such as crop layout and fertilization level, and the spatial variability of S was affected by water conditions, crop layout and fertilization level.（2）The general variability of some soil secondary or micro-elements was basically similar, while the structure of semi-variance was quite different among the villages. （3）Stratified and Rational Distributed Sampling method was recommended to determine the rational sampling quantity of soil nutrients which showed obviously non normal distribution. The sampling quantity obtained by Simple Random Distributed Sampling method was still a good reference.