论文部分内容阅读
以乌鲁木齐县蔬菜主产区的三个乡为例,采用GIS与地统计学相结合的方法对其耕层土壤(0~20 cm)的有机质、全氮、速效氮、速效磷、速效钾等5种养分要素的空间变异特征进行分析。结果表明:全氮变异函数曲线的理论模型能很好地符合球状模型;有机质、碱解氮、速效磷、速效钾的变异函数曲线则符合线性无基台模型。有机质、速效磷和速效钾具有很强的空间相关性,说明受母质、地形、土壤类型等自然的结构性因素影响较大;碱解氮具有中等的空间相关性,说明对施肥、作物、管理水平等随机因素引起的空间相关性起很大作用;全氮的空间相关性很弱,说明人为活动严重削弱了结构性因素造成强的自相关作用。
Taking three townships in the main vegetable producing area of Urumqi as an example, the soil organic matter, total nitrogen, available nitrogen, available phosphorus, available potassium, etc. of topsoil (0-20 cm) were determined by a combination of GIS and geostatistics Spatial variability characteristics of five nutrient elements were analyzed. The results show that the theoretical model of the total nitrogen variability curve can well fit the spherical model; and the curve of variation of organic matter, available nitrogen, available phosphorus and available potassium accord with the linear model without abase. There was a strong spatial correlation between organic matter, available phosphorus and available potassium, which indicated that natural structural factors, such as parent material, topography and soil type, had a great effect on soil structure. There was a moderate spatial correlation between available nitrogen and soil fertility. Level and other random factors play a significant role in spatial correlation; total nitrogen spatial correlation is very weak, indicating that human activities seriously weakened the structural factors resulting in strong autocorrelation.