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The weathering of rocks and minerals of the córrego Rico Watershed processes was studied to understand the internal forces to determine the distribution of soil and relief in space. The objective of this paper is to analyze the relation present in rock formation, soil, relief and water courses in a watershed landscape. Remote sensing orbital image and geographic information system techniques were used in research to data analysis. The multispectral and hyperspectral imagers were available for mapping the land cover, water courses and to process the relief. The physical soil and mineralogy data was collected in field and the samplings were analyzed in the soil and mineralogy laboratories. The exogenic system then transforms rock-forming minerals and their constituent elements into soil showed the differences between relief and soil formation in the area. The landforms composed the watershed landscape was verified. The results showed the influence of relief on soil types and their distribution in the landscape. The areas with higher drainage density present a dissected relief. Ultisols are present in areas of higher drainage density and Latosols are present in areas of lower drainage density, showing a close relationship between relief forms and soil distribution in the landscape. The areas more susceptible to natural erosive processes – Ultisols requires sustainable management in the watershed.

Human land use land cover changes (LULCCs) can cause impacts on watershed lands and on water resources. The regions with land use conflict suffer more intense erosion processes due to their high slope and drainage density. The study intends to evaluate scenarios with an absence of land use conflict and verify if it can contribute to reductions in surface runoff, avoiding the carriage of tailings to river channels. In the study, the SWAT model was used in the hydrological modeling of the Paraopeba River watershed affected by the rupture. The results show that the SWAT model was able to reproduce the flow data with good and very good performances. The quality indicators in the calibration step were NSE = 0.66, R2 = 0.69, PBIAS = 5.2%, and RSR = 0.59, and in the validation, step were NSE = 0.74, R2 = 0.77, PBIAS = 13.5%, and RSR = 0.51. The LULCC from 2000 to 2019 led to a 70% increase in lateral runoff (LATQ) and a 74% decrease in aquifer groundwater. The scenario of land use capability and no conflict can reduce lateral runoff by 37% and increase water infiltration by 265%, minimizing the point and diffuse contamination of the tailings in the Paraopeba river channel.

The ecological functions restoration in agricultural areas is a major challenge on a landscape scale. In the specific case of active restoration through Agroforestry Systems (AFS), the absence of a specific direction hinders ecological restoration processes, especially in regions that prefer intensive agriculture. Thus, this study aims to develop a Spatial Indicator of Priority Areas to guide Agroforestry Systems implementation in agricultural landscapes. A spatial multicriteria decision analysis (MDCA) was carried out based on environmental factors: soil, geology and slope (which determine the natural vulnerability of the land) and anthropogenic factors: land use and land cover, forest fragments, potential land use capacity and legal protected areas in rural properties (which reflects human pressure and land use suitability). Subsequently, four priority levels were classified for agroforestry interventions: (1) Low priority; (2) Average priority; (3) High priority; (4) Extreme priority. A final map was made to identify priority areas for landscape recovery in 9 cities located at the mouth of the Mogi Guaçu River Hydrographic Basin, State of São Paulo, Brazil. Considering the natural vulnerability of the land and the multifunctional aspects of the landscape, the scenarios projection allowed a consensus for forest conservation and agricultural suitability perspectives. A final combination of the explored aspects culminated in the spatial indicator, which model foresees 22,300 ha available for urgent actions for restoration, reforestation and sustainable exploitation through agroforestry systems. We emphasize the challenges in reconciling the socioeconomic and ecological functions in the agroecosystem, however, the metric provides a more inclusive and assertive management strategy for natural resources and advances towards the goal of reforestation and implementation of payment for environmental services (PES) schemes.

Human actions in the drainage network of hydrographic basins interfere with the functioning of ecosystems, causing negative impacts on the environment. Among these impacts, mass loads with a high concentration of phosphorus (P) have a significant potential for point and diffuse pollution of freshwater. The objective of this work was to model P spatially in the Paraopeba River basin, namely in the main water course and 67 sub-basins, and temporally in the years of 2019, 2020, and 2021, after the rupture of B1 tailings dam of Vale, SA company in Brumadinho (Minas Gerais Brazil). The distribution of total phosphorus concentrations (Pt) in relation to environmental attributes (terrain slope, soil class, and land use) and stream flow was assessed with the help of SWAT, the well-known Soil and Water Assessment Tool, coupled with box-plot and cluster analyses. The Pt were obtained from 33 sampling points monitored on a weekly basis. Mean values varied from 0.02 to 1.1 mg/L and maximum from 0.2 to 15.9 mg/L across the basin. The modeling results exposed an impact on the quality of Paraopeba River water in a stretch extending 8.8–155.3 km from the B1 dam, related with the rupture. In this sector, if the contribution from the rupture could be isolated from the other sources, the average Pt would be 0.1 mg/L. The highest Pt (15.9 mg/L) was directly proportional to the urban area of a sub-basin intersecting the limits of Betim town and Belo Horizonte Metropolitan Region. In general, urban sprawl as well as forest-agriculture and forest-mining conversions showed a close relationship with increased Pt, as did sub-basins with a predominance of argisols and an accentuated slope (>20%). There were various moments presenting Pt above legal thresholds (e.g., >0.15 mg/L), mainly in the rainy season.

The Payment for Environmental Services (PES) instrument aims to quantify an Ecosystem Service (ES), so that its production is valued and based on a socioeconomic financial system for conservation. The land use on the terrain and the environmental attributes of a watershed directly interfere in the capacity to store water in the system of a functional unit and can be transformed into an Environmental Service. The proposed methodology aims to determine environmental indicators that can support the valuation of the production of water of better quality. The environmental attributes of geology, soil, slope and land use land cover are measured and analyzed. The zoning of the most vulnerable rural areas was determined for possible implementation of PES programs and valuation of spring water in proportion to the contribution of their water production area in the sub-basin. The methodology has proven to be efficient in determining the most environmentally vulnerable areas, in order to classify water production by sub-basins, and it suggests a market form for financing ecosystem conservation that considers the principles of the provider-receiver (which contribute to the generation of environmental service –water and soil quality) and user-payer (who benefit from and pay for it). The financial incentive to rural producers in watershed areas is only provided when management and conservation practices are carried out through activities of plant and animal production on a sustainable land use.