ABSTRACT Carbon flows into and out of the soil are important processes that contribute to controlling the global climate. The relationship between soil organisms and the climate is interdependent since the organisms that contribute to carbon and greenhouse gas fluxes are simultaneously affected by climate change and soil management. Temperature, soil moisture, pH, nutrient level, redox potential and organic matter quality are key elements affecting the microorganisms involved in organic carbon flows in the soil. Climate, topography (slope and position […]

ABSTRACT: Soil microorganisms are influenced by climate change. However, the effect of climate change on soil cultivable bacteria are unclear. In this study, the composition and diversity of the soil cultivable bacterial community were explored by a dilution–plate method, PCR, and 16S rRNA sequencing in a desert steppe of northern China after repeated NH4NO3 amendments and precipitation manipulation for seven years. The experimental treatments were as follows: control (CK), N addition (+N), N addition plus water addition (+N+W), and N […]

ABSTRACT Microorganisms have a fundamental importance in agricultural ecosystems and may be influenced by several factors, including soil management. The aim of this study was to evaluate the effects of cropping systems and soil covers on the microbial community in soil cultivated with muskmelon (Cucumis melo L.). The experiment was conducted in a randomized complete block design with four replications. The treatments were arranged in a split plot design with cropping systems (no-tillage and conventional tillage systems) assigned to the […]

Most studies related to soil aggregation associate the effect of managements or land use types with the organic matter content. However, a direct evaluation of microorganisms and their processes in undisturbed soil allows a better understanding of the real effect of different managements. The objective of this study was to evaluate the changes induced by different types of land use (pasture, eucalyptus forest, araucaria forest, conventional tillage with carrot, and conventional tillage with pumpkin) on soil chemical properties (pH, Ca, […]

Minas Gerais stands out as the largest coffee-producing state of Brazil. This crop is extremely susceptible to weeds, which can be handled by manual, mechanized and/or chemical methods, which strongly affect production costs and soil quality. In this sense, the objective of this study was to evaluate the effect of different weed control methods in and between coffee rows on the soil microbiota and its processes. For this purpose, soil samples were taken in April 2010 from an Oxisol on […]

Enzymatic activity is an important property for soil quality evaluation. Two sequences of experiments were carried out in order to evaluate the enzymatic activity in a soil (Rhodic Eutrudox) amended with cattle manure, earthworm casts, or sewage sludges from the municipalities of Barueri and Franca. The activity of commercial enzymes was measured by microcalorimetry in the same soil samples after sterilization. In the first experiment, the enzyme activities of cellulase, protease, and urease were determined in the soil samples during […]

The decomposition of plant residues is a biological process mediated by soil fauna, but few studies have been done evaluating its dynamics in time during the process of disappearance of straw. This study was carried out in Chapecó, in southern Brazil, with the objective of monitoring modifications in soil fauna populations and the C content in the soil microbial biomass (CSMB) during the decomposition of winter cover crop residues in a no-till system. The following treatments were tested: 1) Black […]