Soil macrofauna associated with cover crops in an Oxisol from the southwest of Piauí state, Brazil

Abstract

<jats:p>ABSTRACT: The soil macrofauna is fundamental for the maintenance of soil quality. The aim of this study was to characterize the soil macrofauna under different species of cover crops, including monoculture or intercropping associated to two types of soil management in the southwest region of Piauí state. The study was carried out in an Oxisol (Latossolo Amarelo, according to Brazilian Soil Classification System) in the municipality of Bom Jesus, Piauí, distributed in 30 m2 plots. Testing and evaluation of the soil macrofauna were conducted in a 9 × 2 strip factorial design, with combinations between cover crops/consortia and soil management (with or without tillage), with four replications. Soil monoliths (0.25 × 0.25 m) were randomly sampled in each plot for macrofauna at 0‒0.1, 0.1‒0.2, and 0.2‒0.3 m depth, including surface litter. After identification and counting of soil organims, the relative density of each taxon in each depth was determined. The total abundance of soil macrofauna quantified under cover crops in the conventional and no-tillage system was 2,408 ind. m-2, distributed in 6 classes, 16 orders, and 31 families. The results of multivariate analysis show that grass species in sole cropping systems and no-tillage presents higher macrofauna density, in particular the taxonomic group Isoptera. No-tillage also provided higher richness of families, where Coleoptera adult were the second more abundant group in no-tillage and Hemiptera in conventional tillage.</jats:p>

Diffuse Reflectance Spectroscopy for Mapping Soil Carbon Stock in the Gilbués Desertification Region at Brazilian Cerrado

“…The values found for TOC and TN, as well as for C Stock and N Stock, are related to the different levels of degradation present in the study area. The C and N contents decrease with the local erosive processes; however, the agricultural activities developed in the PSMW may have provided different agricultural inputs and plant material to the soil, justifying the high amplitude in the values [1].…”

“…Northeastern Brazil is known worldwide for its great productive potential and the implementation of large-scale agricultural projects involving crops such as soybeans, corn, and cotton, as well as beef cattle [1,2]. The state of Piauí, Brazil, which is one of the units of the Brazilian Federation in this territory, besides being known for excelling in food production, also stands out for harboring the largest area of desertification in the country (6200 km 2 ), known as the Gilbués Desertification Nucleus [2].…”

Linking soil biodiversity and ecosystem function in a Neotropical savanna

“…Litterfall was collected monthly for two years (from May 2018 to April 2020) from two replicated baskets (50 cm × 50 cm) (Scoriza et al, 2012) randomly placed inside each of the 12 plots. All senesced plant material deposited monthly in each basket was carefully collected and placed in paper bags in a total of 576 samples (12 plots × 2 replications × 24 sampling dates).…”

“…Our results suggest that soil epigeic fauna diversity and evenness, but not abundance and taxa richness, are positively influenced by rainfall and soil water content in the studied savanna ecosystem. We expected rainfall seasonality to influence soil epigeic fauna diversity and abundance because these are generally related to soil type, climate, and vegetation (Lavelle and Pashanasi, 1989;Pinheiro et al, 2002;Santos et al, 2020), although studies in the Cerrado are scarce. Apart from soil water content, soil temperaturenot measured in this studyregulates soil fauna, determining its spatial and temporal patterns (Lavelle and Spain, 2001).…”