文献类型：期刊文献

英文题名：Effect of diffuse fraction on gross primary productivity and light use efficiency in a warm-temperate mixed plantation

作者：Liu, Peirong[1] Tong, Xiaojuan[1] Zhang, Jinsong[2] Meng, Ping[2] Li, Jun[3] Zhang, Jingru[1] Zhou, Yu[2]

第一作者：Liu, Peirong

通信作者：Tong, XJ[1];Zhang, JS[2]

机构：[1]Beijing Forestry Univ, Sch Ecol & Nat Conservat, Beijing, Peoples R China;[2]Chinese Acad Forestry, Res Inst Forestry, Key Lab Tree Breeding & Cultivat State Forestry Ad, Beijing, Peoples R China;[3]Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Water Cycle & Related Land Surface Proc, Beijing, Peoples R China

年份：2022

卷号：13

外文期刊名：FRONTIERS IN PLANT SCIENCE

收录：;Scopus(收录号：2-s2.0-85140389808);WOS:【SCI-EXPANDED(收录号:WOS:000875763800001)】；

基金：This study was sponsored by the National Natural Science Foundation of China (31872703; 31570617) and the National Key R & D Program of China~(2020YFA0608101).

语种：英文

外文关键词：gross primary productivity; light use efficiency; diffuse fraction; environmental factors; mixed plantation

摘要：Diffuse radiation (I-f) is one of important variables determining photosynthetic rate and carbon uptake of forest ecosystems. However, the responses of gross primary productivity (GPP) and light use efficiency (LUE) to diffuse fraction (DF) are still poorly understood. We used a 6-year dataset of carbon flux at a warm-temperate mixed plantation site in North China to explore the impacts of DF on GPP and LUE. During 2011-2017, ecosystem apparent quantum yield (alpha) and photosynthesis at photosynthetically active radiation (PAR) of 1800 mu mol m(-2) s(-1) (P-1800) on cloudy days were 63% and 17% higher than on clear days, respectively. Under lower vapor pressure deficit (VPD) and air temperature (T-a) conditions, canopy photosynthesis was significantly higher on cloudy skies than on clear skies. On half-hourly scale, increased DF enhanced alpha and P-1800. Daily GPP peaked at a median DF (=0.5), while daily LUE significantly increased with DF (p<0.01). Both GPP and LUE were mainly controlled directly by DF and PAR. DF had an indirect effect on LUE and GPP mainly through PAR. At high DF levels (>0.5), the increase in LUE did not make GPP enhancement. The direct effect of DF on GPP and LUE under lower T-a and VPD was more sensitive than under higher T-a and VPD. When DF was incorporated into the Michaelis-Menten model, it performed well in the GPP estimation, and the determination coefficient increased by 32.61% and the root mean square error decreased by 25.74%. These findings highlight the importance of incorporating DF into carbon sequestration estimation in North China.