草海流域6种林分枯落物水源涵养功能研究

Study on Water Retention Function of Litters in Six Forest Stands in Caohai Watershed

为草海流域水文生态功能调控与植被恢复的物种组合配置提供依据,以贵州威宁草海流域6种林分(云南松林、云南松-滇杨针阔混交林、滇杨林、茶树林、华山松林、杉木林)枯落物作为研究对象,结合实地测量与室内浸泡法,分析比较其枯落物层厚度、蓄积量及涵养水源过程的差异,并通过坐标分析法综合评价其涵养水源的能力。结果表明:6种林分枯落物层总厚度变化范围在1.34~3.26cm之间,蓄积量变化范围在0.62~3.53 t/hm^2之间,最大持水量在0.76~5.57 t/hm^2之间,最大持水率在119.05~207.69%之间,其中,未分解层的厚度、蓄积量与最大持水量显著高于半分解层;持水量、持水速率与浸水时间分别符合方程:Q=alnt+b,R^2>0.82;v=kt^n,R^2>0.98。综合分析结果表明,6种林分枯落物层水源涵养功能从大到小依次表现为:云南松林(0.30)>滇杨林(0.42)>针阔混交林(1.19)>杉木林(1.35)>华山松林(1.51)>茶树林(2.64)。云南松林的蓄积量最大,滇杨林的持水量最大,持水率最大的为针阔混交林。从涵养水源功能的角度,云南松和滇杨可作为草海流域植被恢复的首选树种。

To provide a basis for the regulation of hydrological ecological function and the species allocation of vegetation in Caohai Watershed,6 forest stands in Weining Caohai watershed(Pinusyunnanensis forest, Pinusyunnanensis-Populusyunnanensis forest, Populusyunnanensis forest,Camellia sinensis forest, Pinusarmandi forest and Cunninghamialanceolata forest)were chosen as research subjects,combined with field measurement and indoor immersion method,the differences in the thickness of litters,accumulations and water conservation processes were analyzed and compared,and the functions of water conservation were comprehensively ranked by coordinate analysis method.The results showed that:the total thickness of the litter layer of the six forest stands varied from 1.34 to 3.26 cm,the amount of accumulation was between 0.62 and 3.53 t/hm^2,and the maximum water-holding capacity was between0.76 and 5.57 t/hm^2,the maximum water-holding ratewas between 119.05 and 207.69%.The thickness accumulation and the maximum water holding capacity of the undecomposed layer were significantly higher than the semi-decomposed layer;the water-holding capacity of the undecomposed layer and the semi-decomposed layer of litter had a significant logarithmic relationship with the water immersion time:Q=alnt+b, R^2 >0.82;the water absorption rate of the litter had a power function relationship with the water immersion time:v=kt^n, R^2 >0.98.The results of comprehensive analysis showed that the water conservation functions of the litter layers in the six forest stands from large to small: Pinusyunnanensis forest > Populusyunnanensis forest >Coniferous and broad-leaved mixed forest > Cunninghamialanceolata forest > Pinusarmandi forest > Camellia sinensis forest.The amount of accumulation of Pinusyunnanensis forest was the largest,the water holding capacity of Populusyunnanensis forest was the largest,and the water holding rate was the largest of Coniferous and broad-leaved mixed forest.From the perspective of water conservation function,it is recommended that the preferred tree species for vegetation restoration are Pinusyunnanensis and Populusyunnanensis in Caohai watershed.