热带北缘地区橡胶林水分利用效率的季节差异及归因分析  

Seasonal differences and attribution analysis of water use efficiency in rubber plantations at the north fringe of the tropics

作　　者：郭沈沈 吴志祥[2] 刘文杰[1] 赵豪 李运帅 王誉博 王鹏[1] GUO Shenshen;WU Zhixiang;LIU Wenjie;ZHAO Hao;LI Yunshuai;WANG Yubo;WANG Peng(College of Ecology and Environment,Hainan University,Haikou,Hainan 570228,China;Rubber Research Institute,Chinese Academy of Tropical Agricultural Sciences/Danzhou National Field Scientific Observation and Research Station for Tropical Agroecosystems,Danzhou,Hainan 571737,China)

机构地区：[1]海南大学生态与环境学院,海口570228 [2]中国热带农业科学院橡胶研究所/海南儋州热带农业生态系统国家野外科学观测研究站,海南儋州571737

出　　处：《热带生物学报》2023年第4期424-432,共9页Journal of Tropical Biology

基　　金：海南省自然科学基金青年基金项目(421QN19);国家自然科学基金地区基金项目(32160320);大学生创新创业训练计划项目(202110589090)。

摘　　要：为了深入了解橡胶树(Hevea brasiliensis)的生态水文和碳水循环耦合过程,依托涡度通量数据,利用EC-LUE模型和Penman-Monteith模型,在模拟橡胶林生态系统总初级生产力(GPP)和蒸散(ET)数据的基础上,分析了2010-2019年橡胶林生态系统WUE季节性差异。并在此基础上,定量评估了各因素对WUE变化的影响。结果表明:(1)从时序变化来看,2010-2019年间橡胶林生态系统雨季WUE(3.52 g·kg^(-1))小于旱季(4.73 g·kg^(-1)),GPP和ET均表现出明显的“单峰型”特征,二者峰值出现在雨季;(2)从归因分析来看,大气因素中,太阳辐射倾向于在旱季抑制WUE的增加(呈现负贡献),但是这种抑制作用被大气因素中的其他因素抵消(呈现正贡献)。在各因素中,对WUE变化贡献最高的因素为地表阻抗,其在旱季倾向于促进WUE的增加,贡献占比为33.29%。橡胶林WUE在雨旱季转换的变化主要受生物物理因素调控。Water use efficiency(WUE),a critical element of carbon and hydrological cycle,plays a key role in land-atmosphere feedback.The seasonal differences of rubber plantation ecosystems in WUE from 2010 to 2019 were analyzed by using the EC-LUE model and the Penman-Monteith model based on the data of gross primarily productivity(GPP)and evapotranspiration(ET).Furthermore,the impact of each factor on the change of WUE was quantitatively evaluated.The factors were then classified into two groups:atmospheric(temperature,atmospheric pressure,water vapor deficit,net radiation,and solar radiation)and biophysical(fraction of photosynthetically active radiation,soil heat flux,aerodynamic resistance,and canopy resistance).The results showed that the rubber plantation ecosystems had a lower WUE(3.52 g·kg^(−1))in the rainy season than in the dry season(4.73 g·kg^(−1))from 2010 to 2019,and that both GPP and ET curves were clearly unimodal,with their peaks all in the rainy season.Solar radiation tended to reduce the increase of WUE in the dry season,indicating a negative contribution,although this suppression was counteracted by other atmospheric factors,showing a positive contribution.Surface impedance,which tended to encourage the growth of WUE in the dry season,had the highest contribution to WUE change,accounting for 33.29%of the total.The WUE change in rubber plantations from rainy to drought seasons were primarily governed by biophysical parameters,which might serve as a reference for a further study of the ecohydrological and carbon-water cycle activities in rubber plantations.

关 键 词：水分利用效率 植被初级生产力 蒸散 橡胶林生态系统 

分 类 号：S718[农业科学—林学] S794.1