杉木闽粤栲异龄复层混交林涵养水源功能

Study on the Water-conserving Function of Different-aged Compound Storied Castanopsis fissa and Cunninghamia lanceolata Plantations

为揭示杉木闽粤栲异龄复层混交林涵养水源功能,2017年在福建沙县对4种保留密度的杉木闽粤栲异龄复层混交林的林分持水量、土壤物理性质和涵养水源功能进行研究。结果表明:与栽植前、杉木纯林相比,各异龄复层林土壤的0~20 cm土层,土壤密度分别下降8.86%、7.78%以上,土壤结构体破坏率分别下降15.12%、11.30%以上,>0.25 mm水稳性团聚体含量分别提高12.55%、9.38%以上,非毛管孔隙度分别提高14.87%、10.76%以上,毛管孔隙度分别提高15.32%、11.68%以上,总孔隙度分别提高15.25%、11.53%以上;20~40 cm土层土壤的上述各项指标均表现出相同变化规律。与对照杉木纯林相比,林分总持水量增加218.312 t·hm-2以上,提高14.68%以上;初渗速度增加13.29%以上,稳渗速度增加14.16%以上,地表径流系数降幅达10.34%以上。说明在杉木林中引入闽粤栲显著改善土壤的物理性质,提升林分的涵养水源功能。

In order to reveal the water-conserving function of different-aged compound storied Castanopsis fissa and Cunninghamia lanceolata plantations.In 2017,the water content,soil physical properties and water conservation function of 4 different retention density of C.lanceolata age-complex mixed-forest forests were studied in Fujian Sha County.The results showed that soil density decreased respectively above 8.86% and 7.78%% in 0~20 cm layer of the soil in different-aged compound storied plantations comapred with that before inter-cropped and pure C.lanceolata control.while structure destruction rate decreased above 15.12% and 11.30%,respectively.Similarly,the content of water-stable aggregates larger than 0.25 mm increased above 12.55% and 9.38%,Porosity of non-capillary tubes increased above 14.87% and 10.76%,Porosity of capillary tube increased above 15.32% and 11.68%,Meanwhile,total porosity increased above 15.25% and 11.53%.All the above indexes of soil show the same law of change in 20~40 cm layer.Compared with the pure forest of C.lanceolata,the total water holding quantity was enhanced above 218.312 t·hm-2,enhanced above 14.68%,initial infiltration speed was enhanced above 13.29%,infiltration speed was enhanced above 14.16%,while surface runoff coefficiency was decreased above 10.34%,the introduction of the C.fissa in the C.lanceolata forest significantly improved the physical properties of the soil and enhanced the water conservation function of the forest.