‘中林46杨’林分耗水特性及其与环境因子的关系

Effects of environmental factors on water consumption properties in poplar 'Zhonglin-46'

应用热扩散原理，采用径流计和自动气象站同步观测树干液流和林内环境因子，分析‘中林46杨’蒸腾耗水规律及其与环境因子关系，旨在为该地区更精确地估计生态用水定额提供科学依据，而且也可为该区域杨树胶合板用材林的造林、营林及流域综合管理提供理论基础。结果表明：在整个生长季的晴天，‘中林46杨’树干液流的日变化呈现明显的单峰宽峰曲线，在4、6-10月的液流速率分别为6.21、12.96、11.07、8.18、5.86和2.98 cm/h；‘中林46杨’在夜间有微弱的上升液流，这可能与根压有关；在生长季树干液流速率与环境因子回归分析结果表明，树干液流受环境因子综合影响，影响大小依次是太阳辐射、空气温度、相对空气湿度、林地10 cm土壤温度和风速，建立的回归方程达到极显著水平。

The stem sap flow characteristic of poplar ＇ Zhonglin - 46＇ trees and their relation to environmental factors Were studied based on the thermal dissipation principle, using stem sap flow determining system and auto weather station. The aim of this study is to provide essential theory about water ecology for developing and managing the plywood plantation for Poplar ＇ Zhonglin - 46＇ in the region, and furthermore to provide the theory about the afforestation, management and Watershed management. It is revealed that The daily variation of stem sap flow of Poplar ＇Zhonglin- 46＇ on clear days in the whole growing season can be described with an evident unimodal curve. The sap flow rates in April, June, July, August, September and October are 6.21,12.96,11.07,8.18,5.86 and 2.98 cm/h, respectively; In the night there is a weak rising sap flow, which may be connected with a root pressure; An enter regression analysis of the sap flow rate per day and environmental factors shows that the stem sap flow can be affected by a number of environmental factors, which,in terms of the influential degree can be arranged in the descending order： total solar radiation, air temperature, relative humidity, 10 cm soil temperature of woodland and wind velocity.