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【目的】研究晋西黄土丘陵区油松、杨树和刺槐3种典型人工林枯落物的持水特性。【方法】采集研究区油松、杨树和刺槐人工林不同层次枯落物,测定其蓄积量、最大持水量、吸水速率、最大吸湿比、有效拦蓄量等持水特性参数。【结果】3个树种人工林地中枯落物的蓄积量依次为油松林(13.72t/hm2)>杨树林(13.42t/hm2)>刺槐林(6.88t/hm2),枯落物的最大持水量依次为杨树林(18.83t/hm2)>油松林(14.24t/hm2)>刺槐林(11.44t/hm2),枯落物的最大吸湿比依次为刺槐林(2.85)>杨树林(2.75)>油松林(2.17),枯落物的有效拦蓄量依次为杨树林(27.23t/hm2)>油松林(22.02t/hm2)>刺槐林(15.80t/hm2)。3种人工林枯落物的吸水过程均表现为在浸水0～3h持水量不断增大、吸水速率由最大不断下降,到4～12h变化趋于平缓,到24h变化基本达到动态平衡。建立了3种林枯落物持水量与浸水时间及吸水速率与浸水时间之间的关系式。【结论】杨树林枯落物的持水能力比油松林和刺槐林强,对土壤的水源涵养作用更明显。
【Objective】 The objective of this study was to investigate the water-holding characteristics of litter in three typical plantations of Pinus tabulaeformis, Poplar and Robinia pseudoacacia in the hilly Loess Plateau. 【Method】 The litter of Pinus tabulaeformis, Poplar and Robinia pseudoacacia plantation were collected at different levels in the study area to determine the water holding capacity parameters such as stock volume, maximum water holding capacity, water absorption rate, maximum moisture absorption ratio and effective storage capacity. 【Result】 The results showed that the accumulation of litter in the three tree species plantations followed the order of Pinus tabulaeformis forest (13.72t / hm2)> poplar forest (13.42t / hm2)> Robinia pseudoacacia forest (6.88t / hm2), litter maximum water holding capacity (18.83t / hm2)> Pinus tabulaeformis forest (14.24t / hm2)> Robinia pseudoacacia forest (11.44t / hm2), the maximum moisture absorption ratios of litter were as follows: Robinia pseudoacacia (2.85)> poplar forest (2.17). The effective interception rates of litter were as follows: Poplar forest (27.23t / hm2)> Pinus tabulaeformis forest (22.02t / hm2)> Robinia pseudoacacia forest (15.80t / hm2). The water absorption of litter in the three kinds of plantations showed that the water holding capacity increased continuously from 0 to 3 hours, the water absorption rate decreased continuously from the maximum to 4 to 12 hours, and reached the dynamic balance after 24h. The relationship between water holding capacity, immersion time, water absorption rate and immersion time of three kinds of forest litters was established. 【Conclusion】 The water holding ability of poplar litter is stronger than that of Pinus tabulaeformis and Robinia pseudoacacia, and it is more obvious to the water conservation of soil.