![]() This study evaluates whether rainfed and irrigated agriculture in Western Bahia were able to sequester carbon and re-establish the soil organic carbon content (SOCC) lost due to land use change. Western Bahia, part of a large Brazilian agricultural frontier, is located mainly in fragile, sandy soils in a tropical seasonal climate with dry winters, characteristics that facilitate soil carbon loss. ![]() ![]() Therefore, mitigation and sustainable planning is vital to decrease the impacts of anthropic actions. The significant increase in agricultural areas has resulted in the progressive reduction of the Caatinga biome. Our model has shown good outcomes in terms of accuracy and concordance (coefficient of determination = 0.98, root mean square error = 0.498, and Lin’s concordance correlation coefficient = 0.907). In 2013, 40.5% of the region’s area had LST between 48.0 and 52.0 ☌, raising ETa rates (~4.7 mm day−1). The highest LST was mainly found in urban areas and/or exposed soil. Low vegetation cover rate was observed by LAI and VC values, with a range of 0 to 25% vegetation cover in 52.3% of the area, which exposes the effects of the dry season on vegetation. On the other hand, in 2017 the lowest annual rainfall values (from 200 to 340 mm) occurred. Rainfall records in 2013 ranged from 270 to 480 mm, with values higher than 410 mm in 46.5% of the study area, concentrated in the northern part of the municipality. In 2013, 70.2% of the study area was composed of Caatinga, while the lowest percentages were identified in 2015 (67.8%) and 2017 (68.7%). The results indicated significant effects of land use and land cover changes on energy balances over time. The principal component analysis was used to select descriptive variables and multiple regression analysis to predict ETa. Moreover, land surface temperature (LST) and actual evapotranspiration (ETa) in Petrolina, the semi-arid region of Brazil, was used. Landsat-8 images were used, along with the Surface Energy Balance Algorithm for Land (SEBAL) in the Google Earth Engine platform, from 2013 to 2019, through spatiotemporal modeling of vegetation indices, i.e., leaf area index (LAI) and vegetation cover (VC). ![]() The main objective of this paper is to determine and analyze the changes in land cover and use, over time, on the biophysical parameters in the Caatinga biome in the semi-arid region of Brazil using remote sensing. In the semiarid climate and fragile soils, the increase in C stocks of SOM fractions is more limited to the row of irrigated mango, compared with the Caatinga.Ĭaatinga biome, located in the Brazilian semi-arid region, is the most populous semi-arid region in the world, causing intensification in land degradation and loss of biodiversity over time. On the other hand, for soils of the interrow of irrigated mango, the C stocks of HS, HF and HvF were lower in 2015 than in 2014. There were no differences in the C of HS in the soil along the row of irrigated mango trees in the 0-0.1 and 0.1–0.2 m layers between 20. In the second year of evaluation, irrigated mango cultivation (soils collected in the row) caused increments of 26.09 and 35.29% in the TOC of the 0–0.1 and 0.1–0.2 m layers, respectively. Irrigated mango cultivation (soils collected in the row) also resulted in increase in the stock of C in LtF in the 0–0.1 m layer in 2014. Irrigated mango cultivation (soils collected in the row) led to higher stocks of TOC, C of HF and HS, compared with the Caatinga in both years evaluated. Samples were collected to determine soil density, and the stocks of TOC and C associated with SOM fractions were calculated. The following variables were determined: contents of total organic carbon (TOC) carbon associated with humic substances – HS (fulvic acid fraction – FAF, humic acid fraction – HAF and humin fraction – HF) carbon associated with light fraction (LtF) and heavy fraction (HvF) and labile C (LC). Thus, in order to evaluate the influence of irrigated mango cultivation on the C stocks of the SOM fractions in a Neossolo Quartzarênico in Petrolina – PE, Brazil, in two consecutive years (20), soil samples were collected in the 0–0.1 and 0.1–0.2 m layers in areas under irrigated mango (planting row and interrow) and Caatinga (taken as reference). One of the attributes sensitive to such alterations is soil organic matter (SOM), considering the climatic semi-arid conditions, fragile soils (sandy soils) and the adopted management such as the organic residues deposition from pruning, goat manure fertilization, high availability of water, and nutrients. The Sub-middle São Francisco Valley is a center of intense activity of irrigated fruit farming, which may lead to alterations in soil attributes and processes compared with areas under native vegetation, in this case Caatinga.
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