珠江源头区几种主要林分类型下土壤的水分涵养功能研究

Study on Soil Water Conservation Functions of Several Vegetation Types in Zhujiang Fountainhead Region

通过对珠江源头区几种主要的植被类型——云南松林、华山松林、云南松+栓皮栎、云南松+旱冬瓜林、旱冬瓜林、滇石栎林、高山栎林等林分土壤的水源涵养功能进行研究,分别从土壤吸湿水分的能力、枯落物截留状况、渗透性能以及水土流失状况方面进行了分析,认为:阔叶林地表枯落物含量较多,分解速度也最快,土壤渗透功能及持水能力也最强,其次为针阔混交林,针叶纯林的持水保土功能最差。地表径流量以针阔混交林<阔叶林<针叶林依次递减,但其差异较大,地表径流最大的云南松针叶林是最小的高山栎灌丛的2.18倍,泥沙量最大的云南松林是最小的云南松+栓皮栎林的25.65倍,而阔叶林与针阔混交林差异不大,研究表明针叶林下土壤的水分涵养功能较差,而针阔混交林和阔叶林则较强。

Based on the analysis of soil water holding capacity, water interception of litters,soil infiltration ability and soil and water loss regime, the soil water conservation functions of several vegetation types Pinus yunnanensis forest, Pinus armandii forest, Pinus yunnanensis ＋ Quercus variabilis forest, Pinus yunnanensis ＋ Alnus nepalensis forest, Alnus nepalensis forest, Lithocarpus dealbatus forest, Quercus aquifolioides forest in Zhujiang fountainhead region were studied. The results indicates that. （1）due to the rich litters and its fast decomposition, the broad leaved forests have the strongest soil infiltration ability and water holding capacity, next the broad leaved and coniferous mixed forests, the coniferous forest is the poorest. （2）the surface runoff are increase by degrees that is the broad leaved and coniferous mixed forests,the broad leaved forests,the coniferous forest in turn. But there is a marked differences of which the highest runoff of Pinus yunnanensis needleleaved forest is 2.18 times of that the lowest Quercus aquifolioides forest and the highest silt amount of Pinus yunnanensis forest is 25.65 times of that the lowest Pinus yunnanensis ＋ Quercus variabilis mixed forest while a minors between the broad leaved forests and the broad leaved and coniferous mixed forests. （3）the soil water holding capacity of coniferous forest is poor while the broad leaved forests and the broad leaved and coniferous mixed forests are higher.