Abstract
Quantification of the temporal and spatial variations of soil respiration is an essential step in modeling soil carbon (C) emission associated with the spatial distribution of plants. To examine the temporal and spatial variations of soil respiration and its driving factors, we investigated soil respiration, microclimate, and understory vegetation in a 50 m × 70 m plot in a climatic transitional zone oak forest in Central China. The temporal variation of soil respiration based on the 21 measurements ranged from 15.01% to 30.21% across the 48 subplots. Structural equation modeling showed that soil temperature and understory shrub biomass had greater positive effects on the seasonal variability of soil respiration. The spatial variation of soil respiration of the 48 subplots varied from 3.61% to 6.99% during the 21 measurement campaigns. Understory shrub biomass and belowground fine root biomass positively regulated the spatial variation of soil respiration. Soil respiration displayed strong spatial autocorrelation, with an average spatial correlation length of 20.1 m. The findings highlight the importance of understory shrub and belowground biomass in regulating the temporal and spatial heterogeneity of soil respiration in forest ecosystems, and the need to carefully address it to robustly estimate the contribution of soil C emission in terrestrial C cycling.
Highlights
Soil respiration represents a major flux of carbon (C) to the atmosphere, releases approximately100 pg C each year [1], and typically accounts for 30%–80% of total ecosystem respiration [2].soil respiration undoubtedly exerts a great influence on atmospheric CO2 concentration, and on climate change [3]
Across the 48 subplots, soil respiration changed from 1.57 μmol m−2 s−1 to 4.13 μmol m−2 s−1, and the temporal variation (CVtp ) of soil respiration averaged 20.64%, differed between 15.01% and
Our study demonstrates the commonly known temporal fluctuation of soil respiration rate, which is consistent with the growing body of literature on temporal patterns of soil respiration rate [36,37]
Summary
Soil respiration represents a major flux of carbon (C) to the atmosphere, releases approximately100 pg C each year [1], and typically accounts for 30%–80% of total ecosystem respiration [2].soil respiration undoubtedly exerts a great influence on atmospheric CO2 concentration, and on climate change [3]. Soil respiration represents a major flux of carbon (C) to the atmosphere, releases approximately. 100 pg C each year [1], and typically accounts for 30%–80% of total ecosystem respiration [2]. Soil respiration undoubtedly exerts a great influence on atmospheric CO2 concentration, and on climate change [3]. It is not easy to accurately predict soil respiration even within the one ecosystem due to its large temporal and spatial variations [4], which are impacted by different biotic and abiotic factors [5]. There is a large uncertainty associated with the prediction of terrestrial C cycling due to the temporal-spatial variability of soil respiration at different scales [6]. Soil temperature can regulate metabolism of plant roots [9,10] and decomposition rate of soil organic matter [11] by changing
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
