Carbon pools and microbial indicators in vineyard soils under organic and conventional fertilization in the São Francisco Valley, in a semi-arid tropical climate.

Soil management systems that do not prioritize conservation contribute to carbon (C) depletion in tropical environments. In the semi-arid region of Brazil, fruit farming has been a key driver for economic development, yet high agricultural yields depend on the use of costly inputs. We conducted a groundbreaking study in São Francisco Valley, northeastern Brazil, to investigate the effects of organic (OF) and synthetic fertilizers (CF) on carbon stock and stability, organic matter fractions, microorganismal carbon biomass (C-mic) and quality indexes, and C-CO emissions up to the 1 m of depth in grapevine soils.

Can C-budget of natural capital be restored through conservation agriculture in a tropical and subtropical environment?

Conservation agriculture through no-till based on cropping systems with high biomass-C input, is a strategy to restoring the carbon (C) lost from natural capital by conversion to agricultural land. We hypothesize that cropping systems based on quantity, diversity and frequency of biomass-C input above soil C dynamic equilibrium level can recover the natural capital. The objectives of this study were to: i) assess the C-budget of land use change for two contrasting climatic environments, ii) estimate the C turnover time of the natural capital through no-till cropping systems, and iii) determine the C pathway since soil under native vegetation to no-till cropping systems.

C-offset and crop energy efficiency increase due industrial poultry waste use in long-term no-till soil minimizing environmental pollution.

Brazil is one of the major global poultry producers, and the organic waste generated by the chicken slaughterhouses can potentially be used as a biofertilizer in agriculture. This study was designed to test the hypothesis that continuous use of biofertilizer to the crops, substituting the use of mineral fertilizer promote C-offset for the soil and generate crop energy efficiency for the production system. Thus, the objectives of this study were to evaluate the effects of biofertilizer use alone or in combination with mineral fertilizer on soil organic carbon (SOC) stock, carbon dioxide (CO) mitigation, C-offset, crop energy efficiency and productivity, and alleviation of environmental pollution.

Driving factors of soil carbon accumulation in Oxisols in long-term no-till systems of South Brazil.

In a climate change scenario, it is important to understand the factors that lead to changes in a soil carbon (C) sink. It is recognized that such process is highly dependent on climate, soil properties, topography, and vegetation. However, few studies demonstrate how these mechanisms operate in highly weathered Oxisols.

Macroaggregation and soil organic carbon restoration in a highly weathered Brazilian Oxisol after two decades under no-till.

Conclusions based on studies of the impacts of soil organic carbon (SOC) fractions and soil texture on macroaggregation and SOC stabilization in long-term (>20years) no-till (NT) fields remain debatable. This study was based on the hypothesis that the amount and frequency of biomass-C input associated with NT can be a pathway to formation of macroaggregates and to SOC buildup. The objectives were to: 1) assess the macroaggregate distribution (proportional mass, class mass) and the SOC and particulate organic carbon (POC) stocks of extra-large (8-19mm), large (2-8mm) and small (0.