Response of soil respiration to environmental and photosynthetic factors in different subalpine forest-cover types in a loess alpine hilly region  

作　　者：Yuanhang Li Sha Lin Qi Chen Xinyao Ma Shuaijun Wang Kangning He 

机构地区：[1]School of Soil and Water Conservation,Key Laboratory of State Forestry Administration On Soil and Water Conservation,Beijing Forestry University,Beijing 100083,People’s Republic of China [2]Beijing Engineering Research Center of Soil and Water Conservation,Beijing Forestry University,Beijing 100083,People’s Republic of China [3]Engineering Research Center of Forestry Ecological Engineering,Ministry of Education,Beijing Forestry University,Beijing 100083,People’s Republic of China [4]North China Power Engineering Co.,Ltd.of China Power Engineering Consulting Group,Changchun 130021,People’s Republic of China [5]Power China Huadong Engineering Corporation Limited,Hangzhou 311122,People’s Republic of China

出　　处：《Journal of Forestry Research》2022年第2期653-665,共13页林业研究（英文版）

基　　金：This work was supported financially by the National Key Research and Development Plan Projects of China(2017YFC0504604).

摘　　要：Soil respiration(Rs)is important for transport-ing or fixing carbon dioxide from the atmosphere,and even diminutive variations can profoundly influence the carbon cycle.However,the R_(s) dynamics in a loess alpine hilly region with representative sensitivity to climate change and fragile ecology remains poorly understood.This study investigated the correlation and degree of control between R_(s) and its photosynthetic and environmental factors in five subalpine forest cover types.We examined the correlations between R_(s) and variables temperature(T_(10)) and soil moisture content at 10 cm depth(W_(10)),net photosynthetic rate(P_(n))and soil properties to establish multiple models,and the variables were measured for diurnal and monthly vari-ations from September 2018 to August 2019.The results showed that soil physical factors are not the main drivers of R_(s) dynamics at the diel scale;however,the trend in the monthly variation in R_(s) was consistent with that of T_(10)and P_(n).Further,R_(s) was significantly affected by pH,providing further evidence that coniferous forest leaves contribute to soil acidification,thus reducing R_(s).Significant exponential and linear correlations were established between R_(s) and T_(10)and W_(10),respectively,and R_(s) was positively correlated with P_(n).Accordingly,we established a two-factor model and a three-factor model,and the correlation coefficients(R_(2))was improved to different degrees compared with models based only on T_(10) and W_(10).Moreover,temperature sensitivity(Q_(10))was the highest in the secondary forest and lowest in the Larix principis-rupprechtii forest.Our findings suggest that the control of R_(s) by the environment(moisture and tempera-ture)and photosynthesis,which are interactive or comple-mentary effects,may influence spatial and temporal homeo-stasis in the region and showed that the models appropriately described the dynamic variation in R_(s) and the carbon cycle in different forest covers.In addition,total phosphorus(TP)and total potassium(TK

关 键 词：Loess alpine hilly region Soil respiration Environmental factor Photosynthesis factor Q_(10) Two-factor model Three-factor model 

分 类 号：S714[农业科学—林学]