Effects of forest cover types and environmental factors on soil respiration dynamics in a coastal sand dune of subtropical China  

作　　者：Wei Gao Zhiqun Huang Gongfu Ye Xinjian Yue Zhiyong Chen 

机构地区：[1]Institute of Geography,Fujian Normal University,Fuzhou 350007,People’s Republic of China [2]Ministry of Education Key Laboratory of Humid Subtropical Eco Geographical Process,Fuzhou 350007,People’s Republic of China [3]Fujian Academy of Forestry Sciences,Fuzhou 350012,People’s Republic of China [4]College of Forestry,Fujian Agriculture and Forestry University,Fuzhou 350002,People’s Republic of China

出　　处：《Journal of Forestry Research》2018年第6期1645-1655,共11页林业研究（英文版）

基　　金：supported by the National Natural Science Foundation of China(31570604,41371269);The Basal Research Fund of Fujian provincial Public Scientific Research Institution support(2014R1011-7);the Casuarina Research Center of Engineering and Technology,and the Key Laboratory of Forest Culture and Forest Product Processing Utilization of Fujian Province

摘　　要：Trees on sand dunes are more sensitive to environmental changes because sandy soils have extremely low water holding capacity and nutrient availability. We investigated the dynamics of soil respiration(Rs) for secondary natural Litsea forest and plantations of casuarina,pine, acacia and eucalyptus. Results show that significant diurnal variations of Rsoccurred in autumn for the eucalyptus species and in summer for the pine species, with higher mean soil respiration at night. However, significant seasonal variations of Rswere found in all five forest stands. Rschanged exponentially with soil temperatures at the 10-cm depth; the models explain 43.3–77.0% of Rs variations. Positive relationships between seasonal Rsand soil moisture varied with stands. The correlations were significant only in the secondary forest, and the eucalyptus and pine plantations. The temperature sensitivity parameter(Q10 value) of Rsranged from 1.64 in casuarina plantation to 2.32 the in secondary forest; annual Rswas highest in the secondary forest and lowest in the pine plantation. The results indicate that soil temperatures and moisture are the primary environmental controls of soil respiration and mainly act through a direct influence on roots and microbial activity. Differences in root biomass, quality of litter,and soil properties(pH, total N, available P, and exchangeable Mg) were also significant factors.Trees on sand dunes are more sensitive to environmental changes because sandy soils have extremely low water holding capacity and nutrient availability. We investigated the dynamics of soil respiration(Rs) for secondary natural Litsea forest and plantations of casuarina,pine, acacia and eucalyptus. Results show that significant diurnal variations of Rsoccurred in autumn for the eucalyptus species and in summer for the pine species, with higher mean soil respiration at night. However, significant seasonal variations of Rswere found in all five forest stands. Rschanged exponentially with soil temperatures at the 10-cm depth; the models explain 43.3–77.0% of Rs variations. Positive relationships between seasonal Rsand soil moisture varied with stands. The correlations were significant only in the secondary forest, and the eucalyptus and pine plantations. The temperature sensitivity parameter(Q10 value) of Rsranged from 1.64 in casuarina plantation to 2.32 the in secondary forest; annual Rswas highest in the secondary forest and lowest in the pine plantation. The results indicate that soil temperatures and moisture are the primary environmental controls of soil respiration and mainly act through a direct influence on roots and microbial activity. Differences in root biomass, quality of litter,and soil properties(pH, total N, available P, and exchangeable Mg) were also significant factors.

关 键 词：Coastal sand dunes Soil respiration Secondary forest PINE CASUARINA ACACIA Eucalyptus plantations Environmental factor Q_(10) 

分 类 号：S7[农业科学—林学]