作物种植前后土壤有机质及养分因子的空间变异分析

Spatial variation analysis of soil organic matter and nutrient factor for before and after planting crops

以作物土壤试验数据为基础,结合多年的农户调查数据,采用Moran's I指数分析、Pearson相关系数分析和Kriging插值3种地统计学方法,探讨了浙江省浦江县作物种植前后土壤有机质及氮磷钾等养分因子的空间演化规律。研究发现Moran's I指数分析证实随着区域范围的加大,各因子间自相关程度产生较大差异。这一点在Pearson相关系数分析中也得到证实,并在kriging插值图中直观表达。结果还表明:有机质和碱解氮的形成与水的关系较为密切,水源区两因子的含量较周边高,且会促进前者向后者转化。养分投入后,过多的养分在土壤中降解过程与区域自然环境条件的关系较密切。同一作物的农户养分投入在不同区域差异较大,不同作物的农户养分投入在区域内却存在量的相关。

The soil organic matter and nutrient factor space evolution for before and after planting crops was discussed,based on data of tested soil and household survey over the years. Results could provide the theoretical basis for reasonable input of crop nutrient and planting structure adjustment to divisional guidance in different regional. The spatial variability of soil factor before and harvest after crops was analyzed by using Moran＇s I index analysis, Pearson correlation coefficient analysis, and Kriging interpolation diagram. Results suggested that three methods can interactly examine and complemente. Moran＇s I index was proved to the great different of nutrient factor of all kinds with the enlarged area coverage,. The correlation degree among all kinds was tested through Pearson correlation. The feature of space distribution in different area could be directly reacted by Kriging interpolation.. The characteristics of used nutrient was showed as following： 1） The soil organic matter and nitrogen was a very close relationship with water, and they had a high content in the water resource district. Results resulted from the accelerated the transformation of nitrogen by water. 2） The a period of time was needed to degradation of a plethora of nutrients in the soil after input nutrient, and this process was closely related with the regional natural environment condition. 3） The calculated result showed a significant correlation between the content of P and K Because of mainly using the compound fertilizer.The content of P and K of soil were higher after harvest crops than before planting crops, which was contributed to the used compound fertilizer with fixed ratio of P and K by farmers. In addition, another reasons is the slower degradation rate of P and K. For the same crop, nutrient inputs by farmers was differend in different regional, but it was correlations in quantitative in the area for different crop. Input nutrient in the same area was the relatively small differences between in conventional rice crop and in scale management grape. However, input nutrient was bigger different for other crops. Spatial analysis results was basically agreed with the peasant household survey results. Nitrogen input should be properly controlled in high mountain, suburban vegetable growing areas, and pot source river downstream zone due to high input nitrogen. The high content of soil P was also properly needed to control in Mountain surrounding. The content of input K is usually not high. Although the the K content in some areas is higher, it is mainly distributed in the high mountains areas, which may be related to the trees.