散射辐射比例对华北平原杨树人工林生态系统能量分配的影响
Impacts of Diffuse Radiation Fraction on Energy Partitioning in a Poplar Plantation in the North China Plain
徐磊 1吴小云 1律江 2石云 2朱梦洵 3许行 1张志强1
作者信息
- 1. 北京林业大学水土保持学院 北京 100083;山西吉县森林生态系统国家野外科学观测研究站 临汾 042299
- 2. 北京市共青林场 北京 101300
- 3. 中咨集团生态技术研究所(北京)有限公司 北京 100037
- 折叠
摘要
[目的]在全球辐射总量及其组成显著变化的背景下,明确散射辐射比例(Fdif)对华北平原杨树人工林生态系统能量分配的影响,为准确评估杨树人工林的生态服务功能和进一步完善生态系统过程模型提供科学依据.[方法]利用涡度相关技术和小气候观测,对 2019、2021年生长季(DOY 91～304)杨树人工林生态系统的能量通量和环境因子开展研究.[结果]华北平原杨树人工林生态系统能量分配在生长季中期(DOY 152～243)以潜热通量(LE)为主,在生长季初期(DOY 91～151)和末期(DOY 244～304)以显热通量(H)为主.Fdif与波文比(β)呈显著负相关(P<0.01),与冠层导度(Gs;P<0.01)、冠层分离指数(Ω;P<0.05)和Priestley-Taylor系数(α;P<0.01)呈显著正相关.通径分析结果表明,Gs是调节华北平原杨树人工林生态系统能量分配的主要因子,Fdif下降时,Gs降低,饱和水汽压差(VPD)增大,生态系统的β显著增大,进而改变生态系统能量分配模式.[结论]Fdif变化影响华北平原杨树人工林生态系统能量分配,Fdif下降会导致能量平衡中的LE所占比例增加、H所占比例相应减小.在气候变化背景下,本研究不仅可深入揭示华北平原杨树人工林生态系统能量分配机制,同时也对准确评估森林生态系统服务功能起到至关重要的作用.
Abstract
[Objective]Under the background of obvious shifts in the amount and component of global radiation,this study aims to elucidate the impact of variations in the fraction of diffuse radiation(Fdif)on energy partitioning of a poplar plantation in the North China Plain.[Method]The eddy covariance techniques and microclimate observations were used to investigate energy fluxes and environmental variables in a poplar plantation during the growing seasons of 2019 and 2021(DOY 91-304).[Result]The energy distribution of the ecosystem primarily consisted of latent heat flux(LE)during the mid-growing season(DOY 152-243),whereas of sensible heat flux(H)during early(DOY 91-151)and late(DOY 244-304)growing seasons.There was a significant negative correlation between Fdif and Bowen ratio(β),and a significant positive correlation between Fdif and Gs,Ω,and α.Path analysis revealed that Gs was the crucial factor regulating the ecosystem's energy distribution.When Fdif decreased,Gs decreased,saturated water vapor pressure difference(VPD)increased,and the ecosystem's β significantly increased,which in turn altered ecosystem energy partition patterns.[Conclusion]The change of Fdif will affect the energy distribution of the poplar plantation ecosystem in the North China Plain.A decrease in Fdif results in a higher proportion of LE and a lower proportion of H,significantly affecting energy partitioning in poplar plantation ecosystems.In the context of climate change,this study not only provides a deep insight into the energy allocation mechanisms of poplar plantation ecosystems in the North China Plain,but also plays a crucial role in accurately assessing the ecological service functions of these forests.
关键词
散射辐射/杨树人工林/能量分配/通径分析/华北平原Key words
diffuse radiation/poplar plantation/energy partition/path analysis/North China Plain引用本文复制引用
基金项目
中国科协青年人才托举工程项目(YESS20230091)
国家自然科学基金(32301664)
中央高校基本科研业务费专项(QNTD202303)
中国博士后科学基金特别资助项目(2023T160055)
中国博士后科学基金特别资助项目(2022M10407)
国家重点研发计划(2022YFF1302501)
出版年
2024
国家科技期刊平台
NSTL
万方数据