Microbiological attributes of yellow oxissol under different monocultures in the savanna region of Piauí state

Abstract

Microbial biomass is an important component in maintaining soil quality and plant productivity.The aim of this paper was to evaluate alterations in microbiological attributes and organic carbon in accordance with seasonal change in different monocultures in the Savanna region of Piauí state. Soil samples were collected in areas of soy, eucalyptus, pasture, and in an area of native savanna, at depths of 0-0.20 m, during the rainy and dry periods. Using these samples microbial biomass carbon (MBC), basal respiration (BR), metabolic quotient (qCO 2 ), microbial quotient (qMIC), and total organic carbon in the soil (TOC) were evaluated. MBC differed significantly between the systems evaluated, with higher values in the soil under native vegetation in the two sampling periods. TOC presented a significant difference between the systems, with higher values in the native savanna and soybean in the rainy period. For the qMIC, the soybean area presented lower values in the two periods compared with the other areas. Basal respiration as well as qCO 2 values differed between the systems only in the dry period. The results reveal that the type of vegetation cover, management system, and seasonality influence the behavior of biological properties in the soil.

Soil biological attributes in monoculture and integrated systems in the Cerrado region of Piauí State, Brazil

“…This expansion, which transforms natural environments into agricultural systems, impacts soil quality indicators because conventional cultivation system are generally adopted during the agricultural exploration of new areas, with soil tillage by heavy machines and the absence of vegetation cover. Thus, in addition to the low nutritional quality of cultivated species, this cultivation system can negatively alter the soil microbiological attributes (Ferreira, Stone, & Martin-Didonet, 2017;Nunes et al, 2018).…”

“…Studies have shown that integrated production systems promote increases in the carbon contents of microbial biomass as well as in soil enzymatic activity (Balota et al, 2014;Stieven, Oliveira, Santos, Wruck, & Campos, 2014;Nunes et al, 2018).…”

Soil microbiological activity under different vegetation coverages in the Cerrado biome of Tocantins state

“…Lower values qMIC in agriculture area compared to the other areas indicate that there are lower proportions of labile organic matter and stable soil organic matter (MGANGA; RAZAVI; KUZYAKOV, 2016). qMIC values below 1.0 indicate a slower process for mineralization of OM in these systems (NUNES et al, 2018). Another interesting factor is that in 10-20 cm layer qMIC was superior in all evaluated areas, which may indicate a better quality of SOM, or even a better efficiency of microorganisms in the use of organic compounds in this depth soil.…”

“…Another interesting factor is that in 10-20 cm layer qMIC was superior in all evaluated areas, which may indicate a better quality of SOM, or even a better efficiency of microorganisms in the use of organic compounds in this depth soil. Nunes et al (2018), evaluating microbiological attributes in different monocultures in the Cerrado of Piauí state, found a qMIC that varied from (1.06 to 2.66 %). Data that corroborate with presented in this study.…”