苏北海堤防护林冠层截留降水特性研究

STUDY ON THE INTERCEPTIONAL CHARACTERISTIC OF MAIN SHELTERFOREST CANOPIES ON SEAWALL IN JIANGSU PROVINCE

对苏北海堤主要防护林类型林冠层降水分配格局及其影响因素的分析结果表明:各林分冠层在降水分配格局方面有较大差异,柳杉林冠层截留率(29.4％)>水杉林(25.7％)>刺槐林(17.5)。透流率则是刺槐林(75.7％)>水杉林(68.2％)>柳杉林(66.0％)。刺槐林和水杉林树干径流率明显高于柳杉林,分别为6.35％、6.1％和4.65％。各林分冠层截留率随降雨量级增大而递减。水杉、刺槐林在落叶期截留率比柳杉林低20％,盛叶期柳杉林与水杉林相近,比刺槐林高10％～15％。另外,在逐步回归分析基础上,筛选出了影响林冠截留的主要降水特性因子,并给出了各林分冠层降水截留量预报模型。

Through a study on the patterns of rainfall redistribution in main shelter-forest canopies and their influential factors in Northern Jiangsu Province's seawall, this paper present the research results as follow: the inter-ceptional rates of these shelter-forests are Chinese cryptomeria(29. 4 %)> Water fir (25. 7% )> Black locus (17. 5%), but the throughfall rates and stemflow rates of these three forests are Crypetomeria(66. 0%)<Wa-ter fir(68. 2%)<Black locus(75. 7%) and Chinese cryptomeria (4. 65%)<Water fir (6. l%)and Black locus (6. 35%). The interceptional rates of these forest's decrease with the increase of rainfall quantity. During the deciduous period, the interceptional rates of Water fir and Black locus are less than that of Chinese cryptomeria by 20%. During the graving period, Cryptomeria's canopy interceptional rates are nearly the same as that of Water fir, but they are bigger than that of Black locus by10-15%. This paper also set up some regression models showing the relationship between the interceptional quantity and precipitation characteristics in three shelter-forest types.