Partitioning of root, litter and microbial respiration by plant input manipulation in forests

Abstract

Soil respiration (Rs) is the largest carbon (C) flux from terrestrial ecosystems to the atmosphere and is of great significance to the global C budget. An increasing number of studies have assessed Rs through in situ observations and model estimates over the last decades, but the sources and pathways of soil carbon dioxide (CO2) are not fully understood, and great uncertainty remains in Rs partitioning of soil CO2 sources. Here, we compiled 236 paired observations that measured soil CO2 fluxes after concurrently removal of living roots (and rhizosphere), litter, and both roots and litter in plant input manipulation experiments conducted at 14 forest sites to partition root + rhizosphere (Rr), litter (Rl) and soil organic matter-derived microbial respiration (Rm) in total soil CO2 flux. We found that Rr, Rl and Rm accounted for 20.1%, 21.8% and 62.7% of the total Rs, respectively. Mean annual precipitation (MAP) was the most important factor driving Rr/Rs, Rl/Rs and Rm/Rs, and MAP was positively correlated with Rr/Rs and Rl/Rs but negatively correlated with Rm/Rs, suggesting a significant climatic control over the proportions of Rs components. Across all sites, the proportions of Rr/Rs and Rl/Rs increased but Rm/Rs decreased with the increase in soil CO2 flux, suggesting that the proportions of root- and litter-derived soil CO2 are generally higher in the tropics than in cold temperate and boreal forests. More accurate partitioning of Rr, Rl and Rm to elucidate different sources and pathways of soil CO2 flux will provide important insights for the global Rs assessment and terrestrial C budget.

The Vegetation Characteristics of Pinus Taiwanensis Drive the Changes in Different Components of Soil Respiration in Wuyi Mountain, Southeast China

“…In addition, similar to W R , litter-derived respiration is part of the total soil respiration, and R S generally be reported as linearly increased with litter production (Zhang et al, 2016b). This may be due, at least in part, to the litter production strongly in uences soil C sources and regulates microbial activities in the forest ecosystem (Zhang et al, 2016b;Zhu et al, 2023). Consistent with prior studies, we observed that R S linearly increased with increasing LAI.…”

Twenty Years of Progress, Challenges, and Opportunities in Measuring and Understanding Soil Respiration

“…A subsequent workshop in 2007 highlighted the opportunities for using automated soil respiration measurements (Carbone & Vargas, 2007). Focused reviews have surveyed methods to partition autotrophic (Ra) and heterotrophic (Rh) respiration (Hanson et al., 2000; Kuzyakov, 2006; Kuzyakov & Larionova, 2005; J. Zhu et al., 2023), the links between photosynthesis and Rs (Kuzyakov & Cheng, 2001; Kuzyakov & Domanski, 2000; Kuzyakov & Gavrichkova, 2010; Vargas, Baldocchi, et al., 2011), Rs response to elevated CO 2 and temperature (Davidson & Janssens, 2006; Jackson et al., 2009; Pendall et al., 2004; Zak et al., 2000), inferring carbon allocation using isotopes (Brüggemann et al., 2011), above‐ and belowground Rh under ecosystem disturbance (Harmon et al., 2011), and wetting or thawing effects on Rs (D.‐G. Kim et al., 2012).…”

“…Focused reviews have surveyed methods to partition autotrophic (Ra) and heterotrophic (Rh) respiration (Hanson et al, 2000;Kuzyakov, 2006;Kuzyakov & Larionova, 2005; J. Zhu et al, 2023), the links between photosynthesis and Rs (Kuzyakov & Cheng, 2001;Kuzyakov & Domanski, 2000;Kuzyakov & Gavrichkova, 2010;, Rs response to elevated CO 2 and temperature Jackson et al, 2009;Pendall et al, 2004;Zak et al, 2000), inferring carbon allocation using isotopes (Brüggemann et al, 2011), above-and belowground Rh under ecosystem disturbance (Harmon et al, 2011), and wetting or thawing effects on Rs (D.-G. Kim et al, 2012). In the last decade, Rey (2015) discussed the importance of considering abiotic Rs sources and transport processes, while M. Xu and Shang (2016) examined the uneven distribution of global Rs measurements, factors affecting Rs computation at different spatial scales, and estimated the global Rs flux.…”

Interactive effects of climate warming and management on grassland soil respiration partitioning

“…There is a large uncertainty associated with the amount of respiration originating from each of these sources due to variations in ecosystem properties and the interactive effects of climate change and management/land use (Jones et al, 2009; Nguyen, 2003). There are some studies which evaluate the partitioned soil respiration into roots, mycorrhizae and microbes (e.g., in forest: Heinemeyer et al, 2007 and Zhu et al, 2023; in barley field: Moyano et al, 2007), but there are only a few to date in grasslands ecosystems due to difficulty in separating root from mycorrhiza hyphal respiration. Heinemeyer et al (2012) in a grassland study found that mycelium respiration contributed to 27% of soil respiration, while root respiration contributed to 11%, with considerable variation across the experimental period.…”