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本文以北京市松山国家级自然保护区5种典型天然纯林为对象,对其枯落物层和土壤层水文效应进行了初步研究,结果表明:枯落物总储量变化范围在3.68 t.hm-2-27.90 t.hm-2,顺序为:山杨纯林>油松纯林>五角枫纯林>蒙古栎纯林>黑榆纯林,最大持水量的变化范围为17.11 t.hm-2-89.14t.hm-2,顺序为油松纯林>山杨纯林>五角枫纯林>蒙古栎纯林>黑榆纯林,山杨纯林有效拦蓄能力最强,为54.41 t.hm-2,黑榆纯林最弱,为12.00t.hm-2;未分解层枯落物8h基本达到饱和,半分解层在6h已经达到饱和,持水量与浸泡时间呈明显对数关系,R>0.95;枯落物在浸水的0.5h内吸水速率最大,4h左右时下降速度明显减缓,枯落物吸水速率与浸泡时间呈明显幂函数关系,R>0.97;土壤容重均值变化范围为1.14 g.cm-3-1.59g.cm-3,总孔隙度的变动范围为27.75%-33.92%;黑榆纯林土壤层有效持水能力最强,为37.27 t.hm-2,山杨纯林最弱,为23.27 t.hm-2,土壤入渗速率与入渗时间呈明显幂函数关系,R>0.95。
In this paper, five typical natural pure forests in Songshan National Nature Reserve of Beijing were studied for their hydrological effects on litter and soil layers. The results showed that the total reserves of litter ranged from 3.68 t · hm -2-27.90 t.hm-2, with the order of: Populus simonii> Pinus tabulaeformis> Pinus tabulaeformis pure forest> Quercus mongolica pure forest> Ulmus pumila pure forest, the maximum water content varied from 17.11 t.hm-2- 89.14t.hm-2, the order was pure forest of Pinus tabulaeformis> pure forest of Populus euphratica> Pure forest of Pentagon> Quercus mongolica> Pure forest of Ulmus pumila and Populus euphratica, with the highest effective interception capacity of 54.41 t.hm-2, The weakest part of pure forest was 12.00t.hm-2; the litter of undistorted layer reached the saturation basically in 8h, the semi-decomposed layer reached saturation in 6h, and the water holding capacity was obviously logarithmic with immersion time, R> 0.95; The water absorption rate was the highest in 0.5h immersion, and the descending speed was obviously slowed down in about 4h. The water absorption rate of litter showed a significant power function relationship with immersion time (R> 0.97). The average soil bulk density ranged from 1.14 g · cm- 1.59g.cm-3. The total porosity ranged from 27.75% to 33.92%. The effective water holding capacity of the pure Ulmus pumila forest soil layer was 37.27 t.hm-2, the weakest of which was 23.27 t. hm-2, Soil infiltration rate and infiltration time showed a significant power function, R> 0.95.