摘要
植被林冠层降雨再分配是森林生态系统重要的水文过程,其研究对进一步探索太行山植被林冠层的水文效应,揭示森林生态系统水源涵养功能具有重要意义。选取位于中国科学院太行山山地生态试验站自然荆条灌丛以及人工刺槐林、白皮松林、黄连木林、樱桃林、杜仲林、白蜡林、竹林为研究对象,于2022年7—9月对8种林分的降雨再分配进行监测。结果表明:1)2022年雨季次降雨量波动性较大,降雨时间分布不均主要集中在7月、8月。2)总穿透雨量占总降雨量的比例均超过60%;总树干径流量占总降雨量的比例最大的为杜仲林(13.94%),其次为竹林(6.78%),其余树种总树干径流量所占比例均低于5%;总冠层截留量占总降雨量的比例,白蜡林最大(32.97%),白皮松林最小(7.53%),整体上表现为穿透雨量>冠层截留量>树干径流量。3)穿透雨量、树干径流量与林外降雨量呈一元线性函数关系,冠层截留量与林外降雨量呈幂函数关系,穿透雨率和树干径流率与林外降雨量呈对数函数关系(单调增函数);冠层截留率与林外降雨量呈对数函数关系(单调减函数)。降雨再分配特征受降雨量及叶片吸水能力影响较大。因此,合理选择林分类型,调整不同林分比例可减少冠层截留量,提高降水利用效率。
With the implementation of ecological restoration projects,vegetation cover in the Taihang Mountains has increased,but the current situation of water shortages has still not been effectively improved.The impact of increased vegetation on hydrological processes is unknown.As the first action layer of rainfall reaches the terrestrial ecosystem,the vegetation canopy divides rainfall into throughfall,stemflow,and canopy interception.This changes the spatial distribution of the rainfall.Therefore,studying rainfall redis-tribution processes is important for exploring the relationship between vegetation and water.This study selected eight typical forests,natural Vitex negundo,and artificial froests of Robinia pseudoacacia,Pinus bungeana,Pistacia chinensis,Eucommia ulmoides,Cerasus pseudocerasus,Fraxinus chinensis,and Garcinia multiflora.Field monitoring and indoor experiments were conducted to ex-plore the rainfall redistribution characteristics of different forest stands of the Taihang Mountains.The results of the study were as fol-lows:1)During the study year(2022),the rainfall amount was 480.0 mm,rainfall in the rainy season was 283.25 mm,the number of rainfall events in the rainy season was 20,the average amount per rainfall was 14.16 mm,and the variation range of rainfall intensity was 0.05-0.72 mm∙h-1,mainly consisting of rainfall events less than 5 mm∙h-1.The hypo-rainfall in the rainy season of 2022 fluctu-ated greatly,and the uneven distribution of rainfall time was mainly concentrated in July and August.2)The proportion of total throughfall to total rainfall was greater than 60%.The lowest threshold of rainfall amount among eight vegetations for producing throughfall was 0.77 mm;E.ulmoides forest has the largest proportion of total stemflow in total rainfall,with a value of 13.94%,fol-lowed by G.multiflora forest(6.78%),and the proportion of total stemflow in the remaining species was less than 5%.The lowest threshold of rainfall amount for eight vegetations for producing stemflow was 3.35 mm;the proportion of total canopy interception of total rainfall was the largest in F.chinensis forest,accounting for 32.97%,and the smallest in P.bungeana forest,accounting for 7.53%.The overall performance was as follows:throughfall>canopy interception>stem flow.3)Throughfall,stemflow,and canopy interception increased significantly with rainfall.Throughfall rate,stemflow rate,and funneling ratio increased rapidly and then leveled off with increasing rainfall amount.The canopy interception rate decreased rapidly and then leveled off with increasing rain-fall.Rainfall redistribution characteristics were greatly affected by rainfall amount and leaf water absorption capacity.It was found that the canopy interception rate of P.bungeana,R.pseudoacacia,E.ulmoides,and G.multiflora forests was significantly smaller than that of natural V.negundo,which was important for reducing rainfall canopy interception evaporation and increasing effective rainfall.These four forests could therefore be considered for planting in water-shortage areas.Thus,reasonable selection of stand type and adjustment of stand proportions can reduce canopy interception and improve the efficiency of precipitation utilization.The res-ults of this study provide a theoretical basis and data support for the selection of tree species in reforestation projects in the Taihang Mountains.
作者
孙天妙
阳辉
曹建生
SUN Tianmiao;YANG Hui;CAO Jiansheng(Center for Agricultural Resources Research,Institute of Genetics and Developmental Biology,Chinese Academy of Sciences/Key Laboratory of Agricultural Water Resources,Chinese Academy of Sciences,Shijiazhuang 050022,China;University of Chinese Academy of Sciences,Beijing 100049,China)
出处
《中国生态农业学报（中英文）》
CAS
CSCD
北大核心
2023年第9期1471-1481,共11页
Chinese Journal of Eco-Agriculture
基金
河北省自然科学基金创新研究群体项目(D2021503001)
科技基础资源调查专项(2022FY100104)
河北省创新能力提升计划项目(20536001D)
河北省重点研发计划项目(20324201D)资助。
关键词
太行山区
降雨再分配
穿透雨
树干径流
冠层截留
叶片吸水能力
Taihang Mountain
Rainfall redistribution
Throughfall
Stem flow
Canopy interception
Leaf water absorption capacity
