title: Estimating daytime ecosystem respiration to improve estimates of gross primary production of a temperate forest.
abstract: Leaf respiration is an important component of carbon exchange in terrestrial ecosystems, and estimates of leaf respiration directly affect the accuracy of ecosystem carbon budgets. Leaf respiration is inhibited by light; therefore, gross primary production (GPP) will be overestimated if the reduction in leaf respiration by light is ignored. However, few studies have quantified GPP overestimation with respect to the degree of light inhibition in forest ecosystems. To determine the effect of light inhibition of leaf respiration on GPP estimation, we assessed the variation in leaf respiration of seedlings of the dominant tree species in an old mixed temperate forest with different photosynthetically active radiation levels using the Laisk method. Canopy respiration was estimated by combining the effect of light inhibition on leaf respiration of these species with within-canopy radiation. Leaf respiration decreased exponentially with an increase in light intensity. Canopy respiration and GPP were overestimated by approximately 20.4% and 4.6%, respectively, when leaf respiration reduction in light was ignored compared with the values obtained when light inhibition of leaf respiration was considered. This study indicates that accurate estimates of daytime ecosystem respiration are needed for the accurate evaluation of carbon budgets in temperate forests. In addition, this study provides a valuable approach to accurately estimate GPP by considering leaf respiration reduction in light in other ecosystems.
authors.affiliation: State Key Laboratory of Forest and Soil Ecology, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, P.R. China; Changjiang River Scientific Research Institute, Wuhan, P.R. China.
authors.forename: Jinwei
authors.initials: J
authors.lastname: Sun
authors.affiliation: State Key Laboratory of Forest and Soil Ecology, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, P.R. China.
authors.forename: Jiabing
authors.initials: J
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Forest and Soil Ecology, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, P.R. China.
authors.forename: Dexin
authors.initials: D
authors.lastname: Guan
authors.affiliation: Changjiang River Scientific Research Institute, Wuhan, P.R. China.
authors.forename: Fuqi
authors.initials: F
authors.lastname: Yao
authors.affiliation: State Key Laboratory of Forest and Soil Ecology, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, P.R. China.
authors.forename: Fenghui
authors.initials: F
authors.lastname: Yuan
authors.affiliation: State Key Laboratory of Forest and Soil Ecology, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, P.R. China.
authors.forename: Anzhi
authors.initials: A
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Forest and Soil Ecology, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, P.R. China.
authors.forename: Changjie
authors.initials: C
authors.lastname: Jin
mesh_terms: D000465:Algorithms; D018533:Biomass; D002245:Carbon Dioxide / Q000378:metabolism*; D002940:Circadian Rhythm; D017753:Ecosystem; D065928:Forests; D008954:Models, Biological; D010101:Oxygen Consumption / Q000502:physiology* / Q000528:radiation effects; D010788:Photosynthesis / Q000528:radiation effects; D018515:Plant Leaves / Q000378:metabolism / Q000502:physiology / Q000528:radiation effects; D012621:Seasons; D036226:Seedlings / Q000378:metabolism / Q000502:physiology / Q000528:radiation effects; D013472:Sunlight; D013696:Temperature; D014197:Trees / Q000378:metabolism / Q000502:physiology* / Q000528:radiation effects
chemical_list: D002245:Carbon Dioxide