不同干扰程度对金佛山方竹林土壤物理特性及其水源涵养功能的影响

Influence of Different Disturbance Intensity on Soil Physical Characteristics and Water Conservation Function in Chimonobambusa utilis Forests

本文对贵州遵义地区金佛山方竹(Chimonobambusa utilis)林3种不同干扰程度的土壤物理特性及其水源涵养功能等进行了研究,结果表明:干扰对方竹林的土壤容重及土壤孔隙度有比较大的影响,土壤容重均随土层深度的增加而增加,土壤总孔隙度与非毛管孔隙度基本上都是随着土层深度的增加而减小;不同干扰程度枯落物的持水率为:中度干扰>轻度干扰>重度干扰,而总持水量则为:中度干扰>重度干扰>轻度干扰;其平均最大蓄水量为:中度干扰(1237.84t/hm)2>轻度干扰(1198.21t/hm)2>重度干扰(1173.38t/hm2);非毛管蓄水量为:轻度干扰(141.06t/hm)2>中度干扰(114.81t/hm2)>重度干扰(102.67t/hm)2;平均土壤稳渗速率为:轻度干扰(2.20mm/min)>中度干扰(1.77mm/min)>重度干扰(1.00mm/min);从综合情况来看:林地的水源涵养能力(土壤最大蓄水量+枯落物最大持水量)的变化顺序为:总蓄水量中度干扰(1250.56t/hm)2>轻度干扰(1207.33t/hm)2>重度干扰(1184.78t/hm)2。在相同的立地条件下,中度干扰的方竹林的水源涵养功能最好,重度干扰的最差。

The soil physical characteristics and water conservation function of the Chimonobambusa utilis forests in Zunyi, Guizhou with different disturbance intensities have been studied. The results indicate that soil bulk density and porosity were considerably influenced by disturbance. The litter moisture changed in the following order： moderate disturbance 〉 intense disturbance 〉 slight disturbance. The maximum average water-holding capacities varied in the order of moderate （1237.84 t/hm^2） 〉 mild （1198.21 t/hm^2） 〉 severe （1173.38 t/hm^2）. The biggest, the middle and the smallest non-capillary water-holding capacities were in the following： mild 〉 moderate 〉severe, by values of 141.06t/hm^2, 114.81 t/hm^2 and 102.67 t/hm^2, respectively. The average stable infiltration rate of soil changed in the order of mild （2.20mm/min） 〉 moderate （1.77mm/min） 〉 severe （1.00mm/min）. The comprehensive water conservation capacity of the forest land, which meant the ultimate water retention of soil plus the ultimate water holdup of litter, also the total water storage, varied in the following order： moderate （1250.56t/hm^2） 〉 mild （1207.33t/hm^2） 〉 severe （1184.78t/hm^2）. Under the same site conditions, the water conservation function of the bamboo forest under moderate and severe disturbance were separately the best and the worst.