甘肃兴隆山主要森林类型凋落物及土壤层的蓄水功能

Water conservation function of litter and soil layer under main forest types in Xinglong Mountain of Gansu

以甘肃兴隆山青杄林、青杄-白桦林、山杨-白桦林、灌丛林、落叶松林和油松林6种森林类型林下凋落物层和土壤层为研究对象,于2010年进行了不同森林类型蓄水功能的研究。结果表明:(1)凋落物累积量13.40～46.32 t/hm2,油松林是山杨-白桦林的2.71倍;凋落物最大持水量为39.38～85.91 t/hm2,油松林最大,山杨-白桦林最小;(2)土壤密度随土壤深度的加大而增大,毛管孔隙度、总孔隙度、饱和蓄水量、非毛管蓄水量均随土壤深度的加大而减小;6种森林0～60 cm土壤层非毛管蓄水量为413.38～771.71 t/hm2,青杄-白桦林最大,落叶松林最小;(3)6种森林类型总蓄水量为青杄-白桦林(849.76 t/hm2)>青杄林(778.48 t/hm2)>山杨-白桦林(623.24 t/hm2)>油松林(504.80 t/hm2)>落叶松林(492.02 t/hm2)>灌丛林(462.26 t/hm2),青杄-白桦林是灌丛林的1.84倍。因此,天然林随森林的正向演替其蓄水功能先增加后减少。

Taken the litter and soil layer under six main forests（Picea wilosonii,P.wilosonii and Betula platyphlla,Populus davidiana and B.platyphlla,Cotonester multiglorus and Rosa xanthina shrubs,Larix principis-rupprechtii and Pinus tabulaeformis）in Xinglong Mountain of Gansu province as research objects.The water conservation function of the different forests were studied in 2010.The results showed that：（1）The accumulation amount of litters was 13.40-46.32 t/hm2 among six forests,the amount of P.tabulaeformis forest was 2.71 times larger than that of P.davidiana and B.platyphlla forest;the maximum water-holding capacity of litters varied from 39.38 t/hm2 to 85.91 t/hm2.Water-holding capacity of P.tabulaeformis forest was the biggest whereas P.davidiana and B.platyphlla forest was the least.（2）The bulk density of forest soil in Xinglong Mountain were augmenting with the increment of soil depth,whereas the capillary porosity,total porosity,maximum water-storage and non-capillary water-storage were all decreasing with the increment of soil depth;non-capillary water-storage of 0-60 cm soil layer was 413.38-771.71 t/hm2 among six forests.Non-capillary water-storage of P.wilosonii and B.platyphlla forest was the biggest whereas L.principis-rupprechtii forest was the least.（3）Total water-storage of six forest types was P.wilsonii and B.platyphlla forest（849.76 t/hm2）P.wilsonii forest（778.48 t/hm2）P.davidiana and B.platyphlla forest（623.24 t/hm2）P.tabulaeformis forest（504.80 t/hm2）L.principis-rupprechtii forest（492.02 t/hm2）C.multiglorus and R.xanthina shrubs（462.26 t/hm2）,the amount of P.wilsonii and B.platyphlla forest was 1.84 times larger than that of C.multiglorus and R.xanthina shrubs.The water conservation function of natural forest firstly increase then decrease with the development of positive forest succession.