辽河源不同林龄油松林水源涵养能力研究

Water Conservation Capacity of Pinus tabulaeformis Forests with Different Ages at Liaohe River

为定量评价不同林龄油松林的水源涵养能力,采用水量平衡法和综合蓄水量法,对辽河源地区3种不同林龄油松林的降雨再分配、凋落物持水能力、土壤蓄水能力以及林分水源涵养能力进行研究。结果表明:(1)观测期间,共观测到112次降雨,累计降雨量902.2mm,平均降雨量8.1mm;小雨、中雨、大雨和暴雨分别占总降雨量的25.2%,35.5%,26.4%和12.9%;(2)不同林龄油松林的林冠截留、林内降雨和树干茎流占总降雨量的比例分别为24.1%,72.9%和3%;林内降雨与林外降雨呈显著正线性关系;随着林龄的增加,林冠截留能力增加,而树干茎流先增加后减少;(3)凋落物的最大持水量、最大吸湿比和有效拦蓄量均随着林龄的增加而增加;(4)随着林龄的增加,土壤容重减小,总孔隙度增加,土壤入渗速率提高,蓄水能力增加;(5)不同林龄油松林水源涵养能力表现为成熟林>近熟林>中龄林。在不同林龄的油松林中,随着演替的进行,林分对降雨的分配与截流能力、水源涵养能力逐步增强。

To evaluate the water conservation capacity of Pinus tabulaeforrnis forest with different ages quan- titatively, water balance method and comprehensive water storage method were used to investigate the rain- fall redistribution, litter water-holding capacity, soil water storage capacity of three Pinus tabulaeformis stands with different ages in Liaohe River. The results showed that. （1）During the observation, a total of 112 times rainfall were observed, cumulative rainfall was 902.2 mm, the average rainfall was 8.1 mm; The light rain, moderate rain, heavy rain and torrential rain accounted for 25.2o//00, 35.5-, 26.4% and 12.9% of the total rainfall, respectively; （2）The percentage of crown canopy interception, forest precipitation and sap flow of Pinus tabulaeformis forests in total rainfall were 24.1%, 72.9% and 3%; There was a significant positive linear relationship between forest precipitation inside and outside; with the increase of forest age, the capacity of crown canopy interception increased, and the sap flow increased first and then decreased; （3） The maximum moisture capacity of litter, the maximum of moisture absorption ratio and effective interception amount increased with the increase of forest age; （4）With the increase of forest age, the soil bulk density reduced, but the total porosity, soil infiltration rate and storage capacity increased. （5）The water conser- vation capacity of Pinus tabulaeformis forest with different ages performed; Mature forest〉near-mature for- est -middle-aged forest. Pinus tabulaeformis at different ages, the ability of rainfall distribution and reten- tion capacity and water conservation capacity increased with the succession.