半干旱沙地樟子松林降雨再分配特征  

Precipitation redistribution characteristics of Pinus sylvestris var.mongolica in semiarid sandy land

作　　者：孙姗姗 刘新平 王翠萍 张铜会 何玉惠 吕朋 车力木格 张腊梅 王明明 程莉 SUN Shanshan;LIU Xinping;WANG Cuiping;ZHANG Tonghui;HE Yuhui;LYU Peng;Chelmeg;ZHANG Lamei;WANG Mingming;CHENG Li(Naiman Desertification Research Station,Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Lanzhou 730000,Gansu,China;University of Chinese Academy of Sciences,Beijing 100101,China;Northwest Surveying,Planning and Designing Institute of National Forestry and Grassland Administration,Xi’an 710048,Shaanxi,China;Forestry and Grassland Service Center in Tongwei County,Gansu Province,Dingxi 743300,Gansu,China)

机构地区：[1]中国科学院西北生态环境资源研究院奈曼沙漠化研究站,甘肃兰州730000 [2]中国科学院大学,北京100101 [3]国家林业和草原局西北调查规划设计院,陕西西安710048 [4]甘肃省通渭县林业和草原服务中心,甘肃定西743300

出　　处：《干旱区地理》2021年第1期109-117,共9页Arid Land Geography

基　　金：国家重点研发计划课题(2017YFC0506706,2016YFC0500907);国家自然科学基金项目(41801076);中国科学院科技扶贫项目:库伦旗草牧业-肉牛养殖一体化脱贫与产业发展模式试验示范;内蒙古自治区科技重大专项课题(Y749BJ1001)。

摘　　要：森林植被的降雨再分配过程是影响区域水资源利用效率以及生态系统生产力的重要因素。于2018年5-8月观测27 a生樟子松人工林降雨再分配特征,探究降雨再分配的比例变化对林地水分平衡的影响机制,分析、量化林内穿透雨、林冠截留、树干径流、枯落物层入渗部分产生的阈值。结果表明:樟子松林内穿透雨量占同期降雨量的86.45%,穿透雨量随着降雨量的增加呈线性增加趋势,降雨量>0.63 mm时产生穿透雨;林冠截留量和树干径流量分别占降雨量的10.44%和2.54%,树干径流量与降雨量之间呈正线性关系,降雨量>1.19 mm时,产生树干径流;枯落物层截留量占降雨量的12.37%,枯落物层截留量随着降雨量的增加而增加;枯落物在0~24 h内平均吸水速率为1.83 mm·h^(-1),其最大持水量为3.23 mm,并且枯落物层截留量占其最大持水量的42.37%。从林冠到枯落物各层截留总量为25.35%,其中有74.65%的雨水最后从枯落物层入渗进入地表,用于补充土壤水分、下渗或补充地下水。半干旱沙地樟子松林可以有效地发挥截留降雨、贮存雨水的功能,继而改善沙地土壤含水量和地下水的有效补给量,提高森林生态系统生产力。The precipitation redistribution process of forest vegetation is an essential factor affecting regional water use efficiency and ecosystem productivity,which can also regulate the mechanism of water resource balance.The precipitation interception by vegetation during and after rain events is an important component of the hydrological cycle of forest ecosystems in arid and semiarid sandy grassland.Pinus sylvestris var.mongolica Litv.is the main water and soil conservation species in the semiarid sandy land.It plays a significant role in regulating regional hydrological processes.There was the water resource deficit and water level drop in Horqin Sandy Land,the precipitation interception by Pinus sylvestris var.mongolica planted forest can affect the regional ecological environment.We investigated the precipitation redistribution characteristics of Pinus sylvestris var.mongolica planted forest in Horqin Sandy Land from May to August in 2018.The study aims to analyze and quantize precipitation redistribution patterns(throughfall,canopy interception,stemflow,and litter layer interception)of Pinus sylvestris var.mongolica.Simultaneously,we calculated how many precipitation magnitudes distributed to the surface soil,to evaluate the regional soil water content and effective supply of groundwater in the planted forest of Pinus sylvestris var.mongolica.A canopy of Pinus sylvestris var.mongolica is the first layer affecting precipitation redistribution.Canopy interception rate decreased and then stabilized with the precipitation increase,which also can be linearly correlated with canopy closure and leaf area index,which is affected by its canopy structure.The atmospheric precipitation passes through the forest canopy to form throughfall,canopy interception,stemflow.Throughfall of Pinus sylvestris var.mongolica accounted for 86.45%of the total precipitation,and linearly increased with the precipitation(y=0.8994x−0.5655,R^(2)=0.9961,P<0.0001).Throughfall occurred when the precipitation exceeded 0.63 mm.The canopy intercept

关 键 词：樟子松林 降雨再分配 冠层截留 枯落物层截留 科尔沁沙地 

分 类 号：S715[农业科学—林学]