The change in the use of the soil causes an imbalance in the ecosystems, altering the chemical and physical properties, which can make their natural recovery unviable. This study aimed to characterize chemically and physically an Entisol under the Caatinga area in a 30 years ecological succession stage in the Semiarid region of Paraiba. The experiment was carried out at the Experimental Station Professor Ignácio Salcêdo, belonging to the National Institute of Semiarid (INSA), located in the municipality of Campina Grande, in the state of Paraíba, soil samples were collected in the 0-10 cm layer, for the determination of pH levels (H2O), exchangeable acidity (Al3+) and potential acidity (H + Al), Ca2+, Mg2+, K+, P, Na+, CTC and SB, Total organic carbon (TOC) and organic matter (OM). In the physical analyses, texture, soil density, particle density, total porosity and aggregate stability were determined. The chemical characterization observed the presence of high levels of K+, Ca2+, Mg2+, CTC and SB, and low levels of Al3+ and Na+ with reduced OM and TOC contents in the 0-10 cm layer. As for physics, the textural classification was sandy loam soil, the soil density, soil porosity and aggregate stability showed values below the critical root growth index in sandy soils. The soil presented recovery characteristics of its chemical and physical quality. The description of the Entisol in the field in soil surveys contributes to a new database in order to predict a better way of use, and these results are references in studies of soil quality recovery in degraded areas in the Caatinga area.

Honey bees play a critical role in ecosystem health, biodiversity maintenance, and crop yield. Antimicrobials, such as tetracyclines, are used widely in agriculture, medicine, and in bee keeping, and bees can be directly or indirectly exposed to tetracycline residues in the environment. In European honey bees, tetracycline exposure has been linked with shifts in the gut microbiota that negatively impact bee health. However, the effects of antimicrobials on Africanized honey bee gut microbiota have not been examined. The aim of this study was to investigate the effects of tetracycline exposure on the gut microbial community of Africanized honey bees (Apis mellifera scutellata x spp.), which are important pollinators in South, Central, and North America. Bees (n = 1,000) were collected from hives in Areia-PB, Northeastern Brazil, placed into plastic chambers and kept under controlled temperature and humidity conditions. The control group (CON) was fed daily with syrup (10 g) consisting of a 1:1 solution of demerara sugar and water, plus a solid protein diet (10 g) composed of 60% soy extract and 40% sugar syrup. The tetracycline group (TET) was fed identically but with the addition of tetracycline hydrochloride (450 μg/g) to the sugar syrup. Bees were sampled from each group before (day 0), and after tetracycline exposure (days 3, 6, and 9). Abdominal contents dissected out of each bee underwent DNA extraction and 16S rRNA sequencing (V3-V4) on an Illumina MiSeq. Sequences were filtered and processed through QIIME2 and DADA2. Microbial community composition and diversity and differentially abundant taxa were evaluated by treatment and time. Bee gut microbial composition (Jaccard) and diversity (Shannon) differed significantly and increasingly over time and between CON and TET groups. Tetracycline exposure was associated with decreased relative abundances of Bombella and Fructobacillus, along with decreases in key core microbiota such as Snodgrassella, Gilliamella, Rhizobiaceae, and Apibacter. These microbes are critical for nutrient metabolism and pathogen defense, and it is possible that decreased abundances of these microbes could negatively affect bee health. Considering the global ecological and economic importance of honey bees as pollinators, it is critical to understand the effects of agrochemicals including antimicrobials on honey bees.

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