Basal soil respiration in land use and cover systems in a caatinga enclaves moist forest

Abstract

Deforestation and the disorderly exploitation of natural resources for agricultural expansion occurred at an accelerated pace in the Brejo microregion of the state of Paraíba, Brazil, which resulted in abandonment and erosion of the soil in a large part of the region. In view of this scenario, the present study was undertaken to investigate the soil respiration in systems involving different forms of land use and cover in caatinga enclaves moist forests (Brejo de Altitude areas). The study was conducted in four land use and cover systems, namely, pasture, mandala agriculture, agroforestry system, and forest. Microbial activity was estimated by quantifying the carbon dioxide (CO2) released in the soil respiration process, from the soil surface, and captured by KOH solution. Soil temperature (°C) and water content (%) were monitored simultaneously with the analysis of soil respiration. The forms of land use and cover have a direct effect on the metabolic activity of soil organisms, and climatic factors such as soil temperature and moisture influence the dynamics of organic matter decomposition and, consequently, the release of CO2. The production of CO2 is higher at night than during the day, regardless of the analyzed systems. Among the evaluated areas, the forest showed the lowest CO2 emissions, so it was considered a CO2 receptor in contrast to the pasture area, which functioned as a CO2 emitter. Management techniques that reduce surface temperature and increase organic matter should be prioritized to promote soil biota.

Dynamics of plant organic matter decomposition in different agricultural landscapes

“…Some studies also found higher leaf litterfall decomposition rates for other arboreal species in periods with higher soil water contents, which result in an intense activity of microorganisms (SOUTO et al, 2013;ALMEIDA et al, 2019;SOUSA et al, 2020). Silva et al (2022) found that areas with natural vegetation present approximately 28% lower soil temperature when compared to areas with little plant cover, and that environmental stimuli, such as temperature and soil moisture, affect the organic matter decomposition dynamics and, consequently, the release of soil CO 2 , indicating that management techniques that reduce the soil surface temperature and increase organic matter contents should be prioritized to improve soil biota. These attributes emerge as important indicators of soil environmental quality, as they estimate the extent of functional sustainability regarding ecological aspects of land use and occupation systems (SILVA et al, 2021).…”

Revision of the Strodei Subgroup of Nyssorhynchus (Diptera: Culicidae), with descriptions of 2 new species

“…The dominant vegetation is Atlantic semi-deciduous forest with trees more than 30 m tall. It has a great variety of habitats with Atlantic forest, Caatinga and Cerrado (da Silva 2018).…”

Comparison of Carbon Dioxide Efflux in Different Land Use Typologies

“…and coffee (Coffea sp.). The soil is of the podzolic type -characterized by its deep profile, clayey texture, and medium to high natural fertility (Araújo et al, 2022).…”

“…Recent research (Mátyás et al, 2020;Gomes et al, 2021;Leal et al, 2020;Silva et al, 2020) has shown that different cropping systems have affected soil respiration and biological activity. Although soil processes play a key role in carbon fluxes, there are still few studies in the Agreste Mesoregion of Paraíba, in particular the Brejo Microregion, on the dynamics of respiration and leaf decomposition and knowing that this information is of great relevance, it is pertinent to make these evaluations (López-Teloxa and Monterroso-Rivas, 2020;Silva, 2022). This study aimed to evaluate CO 2 efflux in different land use typologies.…”