内蒙古砒砂岩不同类型区土壤有机质与速效钾特征

Characteristics of Soil Organic Matter and Available Potassium in Different Types of Pisha Sandstone Area of Inner Mongolia

选择内蒙古鄂尔多斯准格尔旗不同类型砒砂岩区,通过野外采样和室内分析试验,研究了土壤有机质和速效钾特征,并探讨不同土层、坡位和坡向以及植被丰富度等因子对其影响。结果表明:(1)整体上看,覆土区、覆沙区和裸露区有机质含量介于6.65~7.41 g/kg,处于低水平,速效钾含量介于74.61~137.38 mg/kg,处于中高水平。(2)覆土区地形因子对土壤有机质和速效钾的影响最明显,根据3个不同类型区坡向、坡位及坡向与坡位的交互作用对土壤有机质、速效钾呈现的显著或者极显著关系出现频数,初步判断其影响程度大小为坡位(6次)>坡向(4次)>坡向×坡位(2次)。(3)3个类型区植被丰富度指数与土壤有机质、速效钾含量相关性较高,是进行土壤养分研究应考虑的重要因素。

In this study, different types of pisha sandstone in Zhungeer Banner, Ordos, Inner Mongolia were selected to study the characteristics of organic matter (OM) and available potassium (AK) in soil through field sampling and indoor experiments, and the impact of different soil layers, slope position and slope direction, vegetation richness and other factors on OM and AK was also explored. The results showed that: (1) On the whole, the content of OM in the loess covered area, the sand covered area and the exposed area was between 6.65~7.41 g/kg, which was at a low level, and the content of AK was between 74.61~137.38 mg/kg, which was at a medium high level. (2) Topographic factors had the most obvious effect on soil OM and AK in the loess covered area. Slope direction, slope position and the interaction between slope direction and slope position were correlated with soil nutrients, according to the frequency of significant or extremely significant occurrence. The relationship of the degree of influence was preliminarily demonstrated as slope position>slope direction>slope direction×slope position. (3) There was a high correlation between vegetation richness and soil OM and AK content in three different types of regions, which is an important factor to be considered in soil nutrient study.