华北落叶松不同类型林分内植物多样性及土壤持水能力比较

Comparison of Plant Diversity and Soil Water Holding Capacity in Different Stand Types of L.Principis-Rupprechtii

华北落叶松主要分布于华北地区,是优良的用材及水源涵养树种之一,也是塞罕坝机械林场最主要的优势树种,随着人们对森林资源经营的不断探索,对物种更加多样、森林更加健康、植被固碳更佳、水土保持更好的森林结构更加期望,面对林场二次创业之际,广泛营造混交林也是大势所趋,为了给林场下一步造林选择提供科研保障,文章通过对纯林及混交林的植物多样性、枯落物含量、土壤持水能力进行对比分析,寻找较好的混交类型,为林场二次创业保驾护航。本研究选取华北落叶松纯林、落阔混交林、落针混交林作为研究对象,探讨了不同林分类型下生物多样性、枯落物储量、土壤物理性质及持水能力的差异。研究结果表明:落阔混交林和落针混交林的植物丰富度大于落叶松纯林,混交林的Simpson指数、Shannon-Wiener指数、Pielou均匀度指数小于纯林,但相差不大。混交林落针混交林的枯落物层厚度最大为8.93 cm,枯落物总储量的大小关系为:落针混交林>落阔混交林>纯林。落阔混交林、落针混交林的土壤容重均小于落叶松纯林,土壤孔隙度、土壤持水量以及土壤持水率均高于纯林,落针混交林0~10 cm层最大持水量可达到740.62 g/kg,最小持水量达650.17 g/kg,毛管持水量668.95 g/kg,自然含水量434.70 g/kg。

Larix principis-rupprechtii is mainly distributed in North China.It is one of the excellent timber and water conservation tree species,and it is also the most important dominant tree species in Saihanba mechanical forest farm.With the continuous exploration of forest resources management,people have more expectations for the forest structure with more diverse species,healthier forests,better vegetation carbon sequestration and better soil and water conservation.In the face of the second venture of the forest farm,it is also the general trend to extensively build mixed forests.In order to provide scientific research guarantee for the next afforestation selection of the forest farm,this paper compares and analyzes the plant diversity,litter content and soil water holding capacity of pure forest and mixed forest in order to find a better mixed type to escort the second entrepreneurship of the forest farm.In this study,Larix principis-rupprechtii pure forest,deciduous broad-leaved mixed forest and deciduous coniferous mixed forest were selected as the research objects,and the differences of biodiversity,litter storage,soil physical properties and water holding capacity under different forest types were discussed.The results showed that the plant richness of deciduous broad-leaved mixed forest and deciduous coniferous mixed forest was higher than that of larch pure forest.The Simpson index,Shannon-Wiener index and Pielou evenness index of mixed forest were lower than those of pure forest,but the difference was not significant.The maximum thickness of litter layer in mixed forest is 8.93 cm,and the relationship between the total litter storage is:mixed forest>mixed forest>pure forest.The soil bulk density of deciduous broad-leaved mixed forest and deciduous needle mixed forest was lower than that of larch pure forest,and the soil porosity,soil water holding capacity and soil water holding rate were higher than those of pure forest.The maximum water holding capacity of 0~10 cm layer of deciduous needle mixed forest could reach 740.62 g/kg,the minimum water holding capacity was 650.17 g/kg,the capillary water holding capacity was 668.95 g/kg,and the natural water content was 434.70 g/kg.