杉木大径材林地土壤养分变化规律

为了解林地土壤养分状况,本文对黎平县杉木大径材林地土壤进行分级,并检测土壤养分含量变化规律。结果表明:林地土壤pH呈酸性,土壤有机质较丰富、水解氮中等;其中有效磷含量2 mg/kg的6级土壤比例达到77.42%严重偏低;有效磷都分布在5、6级土壤,速效钾集中分布在4、5级土壤;除20～40 cm土层与40～60 cm土层速效钾含量差异不显著外,各养分含量在不同土层之间差异水平显著,有效磷和速效钾含量在不同土层之间达到强变异程度。0～60 cm土层的土壤养分含量总体表现为土壤上层养分含量高于下层土壤,随着土层深度增加而降低。

Changes of Soil Nutrients in Large Diameter Wood Forest Land of Chinese Fir

In order to understand the status of soil nutrients in forest land and provide reference basis and guidance for tending and management measures. In this study, there were 62 samples plots of Chinese fir large-diameter timber were set in Liping County. And collected different soil samples at 0-20cm,20-40cm,40-60cm with the purpose to detect the variation of nutrient content and classification of the soil. The results showed that: the pH of the soil was acidic. The proportion of grade 6 soils less than 2 (mg/kg) reached 77.42%, which was seriously low. The available phosphorus belonged to grade 5 and 6 soils, and the available potassium concentrated in grade 4 and 5 soils. Except the difference of available potassium content between 20-40 cm soil layer and 40-60 cm soil layer was not significant, the differences of nutrient content among different soil layers were significant, and the contents of available phosphorus and available potassium were different. Strong variability was achieved between soil layers. The nutrient content of the soil 0-60 cm soil layer was higher than that of lower soil layer, and decreased with the increase of soil depth. More than three quarters of nutrient content concentrated in 0-40 cm soil layer, and the soil organic matter was rich and hydrolyzed nitrogen was medium.