Diurnal and seasonal variations on soil CO₂ fluxes in tropical silvopastoral systems

Abstract

Soil respiration is a very important component of the global carbon cycle, considered as the second most important carbon (C) flux to the atmosphere and is directly affected by global warming (Xu & Qi, 2001; Bond-Lamberty et al., 2004; Arredondo et al., 2018). It is defined as the sum of autotrophic respiration (i.e. roots and fungi) and heterotrophic respiration (i.e. soil microorganisms that break down organic matter and soil fauna) and is influenced by environmental factors, such as soil and ambient temperature, water content and photosynthetically active radiation (Raich & Schlesinger, 1992; Zimmermann et al., 2009; Cueva et al., 2016). Approximately 30% of the emissions of carbon dioxide (CO 2) come from changes in land use, particularly from deforestation to establish pastures for extensive livestock production (Schimel et al., 2001; Villanueva, 2014). In Mexico, it is estimated that 30%-50% of soil organic carbon

Silvopastoral systems improve carbon stocks at livestock ranches in Tabasco, Mexico

“…Higher C and nutrient input from litterfall in STP favour soil nutrient recycling, which explains the increase in SOC content. The variations in carbon emissions from soil respiration between STP and GM also affect the accumulation of SOC in these livestock systems (Adame‐Castro et al, 2020; Villanueva‐López et al, 2016). These findings showed that the presence of scattered trees in livestock grazing systems (STP) enhances C storage at different soil depths as well as in woody biomass and merits consideration in strategies to mitigate the carbon emissions from animal production systems and for the successful achievement of the SDGs.…”

“…The increasing atmospheric concentrations of greenhouse gases (GHG) are recognized as the main cause of climate change (Adame‐Castro et al, 2020; Villanueva‐López et al, 2019). GHG emissions have increased by more than 40% since preindustrial times, with CO 2 concentrations in the atmosphere increasing from 278 ppm in 1750 to 414 ppm in 2020 (Krishnapriya et al, 2019).…”

Soil CO2 evolution is driven by forage species, soil moisture, grazing pressure, poultry litter fertilization, and seasonality in silvopastures

“…Singh et al (2020) found that cattle grazing grass-dominated cover crops reduced CO 2 efflux compared with grazing legume-dominated cover crops, and overall, grazing compared with nongrazing did not affect cumulative CO 2 emissions. Research on soil respiration differences between forages in silvopastures is limited; however, Adame-Castro et al (2020) reported no cumulative flux differences between Panicum maximum Jacq. and Cynodon plectostachyus (K.…”

“…Research on soil respiration differences between forages in silvopastures is limited; however, Adame‐Castro et al. (2020) reported no cumulative flux differences between Panicum maximum Jacq. and Cynodon plectostachyus (K.…”