The assessment of soil quality is crucial for the sustainable development of agriculture in semiarid regions. Due to their sensitivity to management practices, soil chemical and physical quality indicators are used for investigating soil quality. This study aimed to assess the soil quality of smallholder agroecosystems from the Brazilian semiarid region. Soil physical and chemical attributes were screened using principal component analysis (PCA) and integrated into a weighted additive soil quality index (SQI). Soil quality was obtained using linear and non-linear scoring methods, a total data set (TDS), and a minimum data set (MDS). The soil quality of the agroecosystems was designated as being of moderate grade. The MDS for soil quality assessment includes cation exchange capacity, C stock, exchangeable sodium percentage, flocculation degree, pH, electrical conductivity, available P, and K⁺ from twenty-five indicators of the TDS. This MDS mainly reflects the input of manure and crop residues associated with moderate weathering of easily weatherable minerals given the semiarid conditions. The SQI obtained can be used to synthesize the information of the TDS and is a valuable tool to indicate the soil quality of agroecosystems; thereby, it can be used with indicators of sustainable management for application at a regional scale.

Moringa oleifera is a species of great economic, social and environmental importance, being employed for multiple purposes. Thus, the objective of this study was to fit regression models for estimating leaflets area as non-destructive method from linear measurements of leaflets of M. oleifera seedlings. The study was carried out at the Center for Agrarian and Environmental Sciences of the Paraíba State University. Three hundred leaflets of M. oleifera were collected and measured to determine length “L” and width “W” and, subsequently, leaflets area was quantified through ImageJ® software. Using 200 leaflets, the univariate regression models were fitted, adopting length, width or the product of these dimensions “LW” and a bivariate model based on length and width as predictor variables of the observed leaflets area as dependent variable. The remaining 100 leaflets were used to evaluate the relationship between the observed leaflet area “OLA” and the estimated leaflets area “ELA”, based on Pearson’s correlation “r”; Willmott’s index of agreement “d” and index of confidence “c”; and root mean square error “RMSE”. It was found that allometric models can be used with high accuracy and performance to estimate the leaflets area of M. oleifera as non-destructive method, and recommended model is ELA = 0.035 + 0.720*LW. Future research is suggested for fittings of multivariate models to estimate the leaf area of M. oleifera from varying leaflet sizes, complete leaves, leaf fresh and dry weights, history of life and age of plants.

Brazilian Atlantic Forest hotspots play an important role in global carbon stock and sequestration. Despite this biome is currently under progressive degradation with direct impacts on soils, little information is available on the dynamics of SOC within aggregates under different land uses in patches of this Atlantic Forest hotspot in Brazilian semi-arid. Three typical land uses (woodland, agroforestry system (AFS), and pasture) and different soil layers (0.0–0.2 and 0.2–0.4 m) were evaluated in the humid highlands of northeastern Brazil. Soil aggregate stability and the OC stock and iron oxides (Fe_d) in large macroaggregates (LA: > 2 mm), small macroaggregates (SA: 0.25–2 mm), and microaggregates (MA: 0.25–0.053 mm) were evaluated. Land use affects soil aggregation and distribution of size fractions by altering aggregate-associated OC. OC content was significantly higher in large macroaggregates of woodland and the agroforestry system. Large and macroaggregates-associated OC stocks had a dominant effect on aggregate-associated OC stocks in woodland and the agroforestry system, respectively. The OC stock in the bulk soil of AFS is directly related to the proportions and microaggregate-associated OC stock. Iron oxides also strongly influence the formation of large macroaggregates and microaggregates in the agroforestry system. Thus, AFS stabilizes soil carbon in small macroaggregates and microaggregates (associations with soil minerals), constituting an important aspect of carbon cycling in fragile patches of humid Atlantic Forest in Brazilian semi-arid.

The state of Paraíba, specifically in the alto sertão of Paraíba, is characterized by the spatial and temporal variability of rainfall, of temperature and evapotranspiration, coming from the semi-arid climate that is inserted in the region, and yet, the performance of different meteorological systems. The objective was to quantify the rainfall, temperature and reference evaporation (mm/ month and mm/year) comprised in the experimental period between 2016 to 2020, in the municipality of Catolé do Rocha-PB, in order to determine the history of the rainy and dry season, and thus, minimize agricultural production losses due to environmental factors. The daily rainfall, temperature and reference evaporation data were obtained by means of a rain gauge and the indirect method of the class A tank, respectively. The rainfall (mm year-1) was analyzed by the nonparametric Friedman test, the Conover test and reference evaporation (mm year-1) applied the parametric test of the ANAVA and the test of Tukey HSD. Both parametric and non-parametric tests were analyzed by Real Statistics. Temperature data was compiled from the website (www.inmet.gov.br) in order to control, statically collecting and decision-making in the process of building scientific knowledge regarding meteorological data (climate - Temperature). Were also analyzed pearson's correlation matrices and elementary principal components analysis for the rainfall variables, Eto and Temperature in the studied experimental period. Were also studied the principal component analysis between the years 2016 to 2020 and its significance by the t test. The average reference evaporation between 2016 and 2020 was 2.1 times greater than rainfall. Mean rainfall and reference evaporation in Catolé do Rocha-PB between 2016 and 2020 were 827 mm ano-1 and 1704 mm year-1 and are compatible with historical averages of 800 mm year-1 and 1700 mm year-1, respectively. Inglesa.

Soil health is directly related to sustainable development goals (SDGs) and can be affected by inadequate management practices. In this work, soil edaphic respiration and changes in microbial biomass promoted by cover crops in an integrated crop–livestock system (ICLS) were evaluated using soil health indicators with the respirometry method. The design was completely randomized in a 3 × 6 factorial arrangement, and multivariate principal components analysis (PCA) was performed according to MANOVA. Edaphic respiration was determined based on the respirometry technique. The results showed that edaphic soil respiration was significant in the nine evaluation periods, demonstrating the importance of grass cover in edaphic respiration arising from the biological activity of microorganisms, which is directly related to the amount of soil organic carbon. The cover crops increased soil organic matter and consequently microbial respiratory activity.

Silicon (Si) is a beneficial element that alleviates the adverse effects of salinity in plants. Despite extensive evidence of Si-mediated stress alleviation in other crops, information for tropical fruit species such as Passiflora edulis remains limited, especially regarding the efficiency of different application methods. This study evaluated two yellow passion fruit cultivars (BRS Sol do Cerrado and BRS Gigante Amarelo) at the seedling stage under five management conditions: irrigation with 1.2 dS m⁻¹ water (control), 4.0 dS m⁻¹ water (salt stress), and salt stress combined with Si applied via soil, foliar spray, or both (soil + foliar), using silicic acid as the Si source. The experiment was conducted in a completely randomized design in a 2 × 5 factorial arrangement with five replicates. High salinity decreased foliar nutrient concentrations, gas exchange, and seedling quality, whereas Si mitigated these effects depending on the application method and cultivar. Combined soil and foliar application increased nutrient contents, biomass, and the Dickson Quality Index, especially in BRS Gigante Amarelo. These findings provide new insights into Si management for P. edulis and offer practical implications for improving nutrient balance, growth, and seedling performance under saline conditions.