Effect of thinning intensity on the stem CO_(2) efflux of Larix principis-rupprechtii Mayr

作     者：Kuangji Zhao Timothy J.Fahey Xiangzhen Wang Jie Wang Fang He Chuan Fan Zhongkui Jia Xianwei Li Kuangji Zhao;Timothy J.Fahey;Xiangzhen Wang;Jie Wang;Fang Hie;Chuan Fan;Zhongkui Jia;Xianwei Li

作者机构：Sichuan Province Key Laboratory of Ecological Forestry Engineering on the Upper Reaches of the Yangtze RiverCollege of ForestrySichuan Agricultural University611130 ChengduChina Key Laboratory for Silviculture and Conservation of the Ministry of EducationCollege of ForestryBeijing Forestry University100083 BeijingChina Department of Natural ResourcesCornell University14853 New YorkUSA 

出 版 物：《Forest Ecosystems》 (森林生态系统（英文版）)

年 卷 期：2021年第8卷第4期

页      面：841-855页

核心收录：

学科分类：0710[理学-生物学] 0830[工学-环境科学与工程（可授工学、理学、农学学位）] 0907[农学-林学] 0829[工学-林业工程] 09[农学] 0903[农学-农业资源与环境] 0901[农学-作物学] 0833[工学-城乡规划学] 0713[理学-生态学] 0834[工学-风景园林学（可授工学、农学学位）] 

基　　金：funding from National Natural Science Foundation of China(No.31870387) China Scholarship Council 

主　　题：Stem CO_(2)efflux Thinning intensity Environmental factors Nutrient content Wood structure Nonstructural carbon Larix principis-rupprechtii 

摘      要：Background:Stem CO_(2) efflux(E_(S))plays a critical role in the carbon budget of forest *** is a core practice for sustainable management of *** is therefore necessary and urgent to study the effect and mechanism of thinning intensity(TI)on E_(S).Methods:In this study,five TIs were applied in Larix principis-rupprechtii Mayr 21-,25-,and 41-year-old stands in North China in *** infrared gas analyzer(Li-8100 A)was used to measure ES and its association with environmental factors at monthly intervals from May to October in 2013 to *** addition,nutrients,wood structure and nonstructural carbon(NSC)data were measured in August ***:The results show that ES increased with increasing *** maximum ES values occurred at a TI of 35%(3.29,4.57 and 2.98μmol·m^(-2)·s^(-1))and were 1.54-,1.94-and 2.89-fold greater than the minimum E_(S) value in the CK stands(2.14,2.35 and 1.03μmol·m^(-2)·s^(-1))in July for the 21-,25-and 41-year-old forests,*** E_(S) of the trees in low-density stands was more sensitive to temperature than that of the trees in high-density *** sugars(SS)and temperature are the main factors affecting *** the stand density is low enough as 41-year-old ***-rupprechtii forests with TI 35%,bark thickness(BT)and humidity should be considered in addition to air temperature(T_(a)),wood temperature(T_(w)),sapwood width(SW),nitrogen concentration(N)and SS in the evaluation of *** a change in stand density is ignored,the CO_(2) released from individual 21-,25-and 41-year-old trees could be underestimated by 168.89%,101.94% and 200.49%,***_(2) release was estimated based on the stem equation in combination with the factors influencing ES for ***:We suggest that it is not sufficient to conventional models which quantify ES only by temperature and that incorporating the associated drivers(***,SS,SW and N)based on stand density into conventional model