不同间伐保留密度杉楠复层林的凋落物水文特征OA北大核心CSTPCD

This study investigated the multi-layer forest transformed from Phoebe bournei with four different thinning retention densities and the pure forest of Chinese fir thinning without interplanting in Shunchang County to explore the hydrological effect of litter in the management of Chinese fir interplanting P. bournei into a multi-layer mixed forest. The litters on the forest land were collected and the hydrological indexes such as litter standing crop,water holding rate,interception,and water holding capacity were measured. The result showed significant differences in the amount of litter under the cedar-heath dipterocarp forests with different inter-stocking retention densities,and the total,semi-decomposed,and un-decomposed amounts of apoptotic material increased with the increase of inter-stocking retention densities:Ⅳ(810 tree·hm-2)>Ⅲ(630 tree·hm-2)>CK (pure forest 570 tree·hm-2)>Ⅱ(570 tree·hm-2)>Ⅰ(375 tree·hm-2) the percentage of semi-decomposed layer's accumulation to the total accumulation was higher than that of the un-decomposed layer;the proportion of semi-decomposed layer apomictic litter was greater in the single-story pure forest of fir without interplanting than in the compound forest of broadleaf P. bournei set-aside,while the proportion of un-decomposed layer apomictic litter was the opposite;the water absorption rates of the semi-decomposed layer and the un-decomposed layer were similar,but the water holding capacity and rate were greater in the semi-decomposed layer than in the un-decomposed layer,and both of them were Ⅳ>Ⅲ>CK>Ⅱ>Ⅰ;the maximum retention rate of litters varied from 188. 12％ to 233.54％,and the effective retention amount ranged from 24.39 to 48.54 t·hm-2,both of which showed that Ⅳ>Ⅲ>CK>Ⅱ>Ⅰ. The conversion of pure cedar forests to cedar-heath complex forests resulted in an increase in the amount of litters and its hydrological function in cedar-heath complex forests with a high density of cedar retention,while the opposite was true for those with a lower density of cedar retention,and the density of the complex forests and their stand structure affected the amount of litters in the understory and its hydrological function.