基于Penman-Monteith模型分时段模拟华北落叶松日蒸腾过程  

Simulation of the daily transpiration process of Larix principis-rupprechtii based on Penman-Monteith model

作　　者：陈琪 李远航 王琼琳 王莉 林莎 贺康宁 CHEN Qi;LI Yuanhang;WANG Qionglin;WANG Li;LIN Sha;HE Kangning(School of Soil and Water Conservation,Key Laboratory of State Forestry Administration on Soil and Water Conservation,Beijing Engineering Research Center of Soil and Water Conservation,Engineering Research Center of Forestry Ecological Engineering of Ministry of Education,Beijing Forestry University,100083,Beijing,China)

机构地区：[1]北京林业大学水土保持学院水土保持国家林业局重点实验室北京市水土保持工程技术研究中心林业生态工程教育部工程研究中心

出　　处：《中国水土保持科学》2019年第5期54-64,共11页Science of Soil and Water Conservation

基　　金：国家重点研发计划重点专项“黄土高原人工生态系统结构改善和功能提升技术”(2017YFC0504604)

摘　　要：蒸腾是植被主要的耗水形式,研究黄土干旱地区林木的实际蒸腾量,对于提高林木水分的利用效率,加强林地植被的建设和管理以及维持林分的稳定有着重要的研究意义,同时分析其蒸散耗水特性也对调控水分关系,解决干旱地区水分供需矛盾具有重要的指导意义。笔者以青海省黄土干旱区华北落叶松为研究对象,2018年5-8月,利用探针式茎流计获取华北落叶松生长季树干茎流(10 min频率)的实时数据,结合Penman-Monteith方程反推出的冠层整体气孔阻力γst和便携式自动气象站获取的试验区气象数据,分时段构建了高寒区华北落叶松的γst与气象因子的回归模型,为准确估算华北落叶松的蒸腾量提供科学参考依据。结果表明:1)华北落叶松蒸腾速率的日变化呈现单峰型曲线,树干液流存在明显的时滞现象,滞后时间大约70 min。2)不同时段的γst与饱和水汽压差VPD、温度t均呈负相关关系,与空气相对湿度RH呈正相关关系。气象因子多因素回归效果要优于单因素回归,模拟的平均误差约在14.5%以内。γst与3个气象因素在00:00-08:00时段的多元回归方程为γst=-117376.512+103310.241VPD-3134.50t+1608.292RH;08:00-20:00时段的多元回归方程为γst=-269.467+244.359VPD-20.451t+8.033RH;20:00-24:00时段的多元回归方程为γst=-1570.795-141.384t+49.334RH。[Background]Transpiration is the main form of water consumption in vegetation.It is of great significance to study the actual transpiration of forest trees in arid loess area to improve the utilization efficiency of forest moisture,strengthen the construction and management of forest vegetation and maintain the stability of forest branches.Analysis of its evapotranspiration water consumption characteristics also has important guiding significance for regulating the relationship between water and solving the contradiction between water supply and demand in arid regions.[Methods]This paper takes the Larix principis-rupprechtii in the loess arid area of Qinghai province as the research object.From May to August 2018,the real-time data of the stem sap flow(10 min frequency)of Larix principis-rupprechtii growing season was obtained by using the probe stem flow meter,combined with the Penman-Monteith equation.The inverse total pore resistanceγstof the canopy and the meteorological data obtained from the portable automatic weather station were used to construct the regression model ofγstand meteorological factors of Larix principis-rupprechtii in the alpine region,which provided a basis for accurately estimating the transpiration of L.principis-rupprechtii.It provides scientific reference for the accurate estimation of transpiration of L.principis-rupprechtii.[Results]1)The diurnal variation of transpiration rate of L.principis-rupprechtii shows a single peak curve,and of meteorological elements for sap flow is about 70 min.2)The canopy layer stomatic resistance at different periods was negatively related to VPD and temperature T,and is positively related to air relative humidity RH.By comparison,we can find that the effect of multiple factors regression of meteorological factors is better than that of single factors regression.The simulated results are ideally within an average error of 14.5%.The multivariate regression equation betweenγstand three meteorological factors during the period from 00:00 to 8:00 isγst=-

关 键 词：PENMAN-MONTEITH方程 树干茎流 冠层整体气孔阻力 时滞性 蒸腾模型 

分 类 号：S715.4[农业科学—林学]