山西省中条山4种栎类林分的土壤特性

栎类是我国重要的资源，分析不同栎类林分的土壤理化性质，有利于准确评估土壤肥力，预测栎类林分生长潜力，为栎类林分多目标可持续经营提供参考。选取中条山林局北坛林场栓皮栎纯林、辽东栎混交林、油栎混交林和栓皮栎中林林分3个层次的土壤，比较了不同林分类型土壤pH、有机质、氮素、磷素和钾素含量。结果表明，栓皮栎纯林、辽东栎混交林的土壤pH低于油栎混交林，而土壤表层铵态氮含量、有效磷含量及有效钾含量高于油栎混交林。辽东栎混交林土壤养分含量最高，栓皮栎中林土壤有机质含量最低。随着土壤深度增加，栓皮栎中林有机质含量分别为49.2、13.5和7.9 g·kg^-1，表层土壤全氮含量最低，为2.29 mg·kg^-1。油栎混交林表层土壤全磷、全钾含量最低，分别为1.16和5.68 mg·kg^-1。随着土壤深度的增加，4种林分的土壤有机质、全氮、全磷均呈递减趋势。结果显示栎类阔叶林的养分转化率较栎类针阔混交林好，栎类中林的养分含量较低。

Comparison analysis on soil characteristics of four types of oak stands in Zhongtiaoshan, Shanxi Province

Oak is the important resource in China. Analyzing soil physical and chemical properties of different oak stands is helpful for accurately evaluating soil fertility, predicting growth potential, and can also provide some references for sustainable management of oak stands. In this study, we compared and discussed the pH, organic matter, nitrogen, phosphorus and potassium contents in the soils from three different layers of Quercus variabilis standard stand, Quercus wutaishanica mixed stand, pine oak mixed stand and Quercus variabilis standard stand with coppices in Beitan Forest Farm, Zhongtiaoshan Forestry Bureau. As results, the soil pH of Q. variabilis standard stand and Q. wutaishanica mixed stand were lower than that of pine oak mixed stand, while the contents of ammonium nitrogen, available phosphorus and available potassium in the surface of soil were higher than those of pine oak mixed stand. The soil nutrient content was the highest in Q. wutaishanica mixed stand; the soil organic matter was the lowest in Q. variabilis standard stand with coppices, and with the increase of soil depth, the organic matter content was 49.2 , 13.5 and 7.9 g·kg^-1, respectively, so as the total nitrogen content at the surface, of 2.29 mg·kg^-1. The soil total phosphorus and total potassium contents were the lowest in pine oak mixed stand, of 1.16 and 5.68 mg·kg^-1, respectively. With the increase of soil depth, organic matter, total nitrogen, total phosphorus and total potassium contents in the soils were decreased gradually. In conclusion, the results of this study indicated that the nutrient conversion efficiency of oak broad-leaved stand was better than that of oak coniferous mixed stand, while the nutrient content was lowest in oak standard stand with coppice.