Semiarid soils may be poor in organic carbon, a necessary source of energy for soil microorganisms that affect plant growth. Although the addition of organic carbon may improve soil chemical characteristics, the concentration of humic compounds in the organic component may vary and affect soil chemical composition. We evaluated the effect of two sources of humic compounds on a dystrophic yellow Oxisol cultivated with passion fruit (Passiflora edulis Sims f. edulis) and irrigated with saline water during a severe drought in the Brazilian semiarid region. Soil fertility was evaluated during two seasons. A bovine biofertilizer and an organic commercial amendment (Humistar) were used as sources of humic compounds. Salinity resulted in reduced soil fertility, mainly during the lower rainfall period. The combination of humic substances and salinity increased soil salinity. Humistar, more concentrated in humic acid than fulvic acid, increased both acidity and salinity of the Oxisol under study during the lower rainfall period. Our results contradict the general idea that organic matter can mitigate the harmful effects of salts in semiarid soils because the addition of organic sources to the soil, mainly during a severe drought period, may reduce soil fertility. Although this response may depend on the concentration of humic acids in the amendment, our results suggest that the correction of soil chemistry with the application of either amendment to Oxisols under semiarid conditions, mainly during severe drought, is not economically feasible. Core Ideas Saline irrigation reduces the fertility of Oxisols, mainly in low‐rainfall periods. The combination of humic substances and salinity increased salinity of Oxisols. During low‐rainfall periods, humic substances reduced Oxisol fertility.

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.

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The objective of this work was to evaluate the influence of seasonality on the diversity and richness of the edaphic macrofauna during the dry and rainy periods, in an area of Caatinga in the Brazilian semiarid region. Samples were collected in a sample grid, totaling 10 points, spaced 30 meters apart, in rainy and dry seasons. For quantitative assessment of macrofauna, the total number of organisms (species abundance) was measured, according to diversity. The diversity of the soil macrofauna for this research corresponds to the following order: Hymenoptera> Diptera> Aranaea> Orthoptera> Coleoptera, for the rainy and dry periods, with a greater predominance of the order Hymenoptera. The influence of seasonality was observed in relation to the richness and diversity of the region's macrofauna, with marked fluctuations between the rainy and dry periods.

The semi-arid region of Paraíba is known for the expansion of cultivated areas and agricultural produce, and the high yields and the quality of grapes. The objective of this work was to evaluate the quality table grapes for classification purposes according to the physical and physicochemical characteristics marketed in a local fair in the city of Areia - PB. The work was developed at the Laboratory of Technology of Agricultural Products (LPTA), Federal University of Paraíba (UFPB), Center of Agricultural Sciences (CCA), Campus II, Areia-PB. Table grapes were purchased at the free fair in the municipality of Areia. Two clusters were selected and analyzed according to the Standardization Primer and Classification of the Brazilian Program for Modernization of Horticulture, identifying the group, subgroup, class, subclass, category and the presence of defects (severe or mild). According to the evaluations carried out from the standardization primer, the fruits were slightly damage and/but not changing in their post-harvest quality. The fruits were classified according to commercial standards and suitable for human consumption.