摘要
林冠对降雨雨滴的汇聚与分散影响林下雨滴的质量和动能。定义一个新的指标“雨滴聚散比”来描述林冠对雨滴汇聚能力的大小,通过量化有多少个林外小雨滴汇聚成1个林内大雨滴来研究不同降雨强度和降雨量条件下,北京西山林场样地林冠对雨滴的汇聚作用。研究结果表明:降雨出现在侧柏林时,林内穿透雨量占林外总降雨量的比例最大,其次为林冠截留量,最后为树干茎流量。小径级雨滴(<1 mm)对林内外降雨量的贡献率始终最大,大径级雨滴(>3 mm)对林内外降雨强度的贡献率始终最低。雨滴聚散比曲线在不同雨强条件下呈单峰变化趋势,在不同雨量条件下则呈双峰变化趋势。在雨强为2.20 mm/h时,雨滴聚散比为9,即林外9个小雨滴转化为1个林内大雨滴。北京北部山区侧柏林冠对降雨雨滴主要起汇聚作用,其汇聚能力大小随降雨强度呈单峰变化趋势,随降雨量呈双峰变化趋势。
The aggregation and dispersion of raindrops by canopy affect the mass and kinetic energy of raindrops under the forest.A new parameter“raindrop convergence rate”was defined in this paper to describe the raindrop convergence capacity of the forest canopy.By quantifying how many small raindrops outside the forest converge into one large raindrop inside the forest,the canopys effect on raindrop convergence was studied under the conditions of rainfall intensity and rainfall.The main research results are as follows:a)The proportion of total rainfall in Robinia pseudoacacin forest is the highest,followed by canopy interception,and the proportion of stem flow is the lowest.b)The contribution rate of small diameter raindrop(<1 mm)to rainfall intensity inside and outside the forest is always the highest,while that of large diameter raindrop(>3 mm)is always the lowest.c)The raindrop convergence rate curve shows a unimodal trend under different rainfall intensification conditions,and a bimodal trend under different rainfall conditions.When the rain intensity is 2.20 mm/h,the convergence rate of raindrop is 9,that is,9 small raindrops outside the forest are transformed into 1 large raindrop inside the forest.It can be seen that the canopy of Robinia pseudoacacin in Beijing mountain area mainly plays an aggregation role in raindrops,and its aggregation capacity presents a unimodal curve with rainfall intensity and a bimodal curve with rainfall.
作者
孙丰宾
张展硕
乔林
余新晓
SUN Fengbin;ZHANG Zhanshuo;QIAO Lin;YU Xinxiao(Beijing Institute of Urban Meteorology,Beijing 100089,China;Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029,China;Yellow River Institute of Hydraulic Research,Zhengzhou 450003,China;Beijing Weather Forecast Center,Beijing 100089,China;Beijing Forestry University,Beijing 100083,China)
出处
《人民黄河》
CAS
北大核心
2023年第12期25-30,共6页
Yellow River
基金
国家自然科学基金资助项目(42230714)
国家自然科学联合基金之黄河水科学研究联合基金资助项目(U2243202)。
关键词
雨滴汇聚速率
截留
植被冠层
降雨特性
raindrop convergence rate
interception
vegetation canopy
rainfall characteristics
作者简介
孙丰宾(1985—),男,山东泰安人,工程师,博士,主要从事水文水资源与水环境研究工作;通信作者:乔林(1965—),男,河南郑州人,研究员,研究方向为气象学,E-mail:bjs_qxt@sina.com。
