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Land use is a driver for hydrological and soil erosion responses at the watershed scale. This study aimed to assess the hydrological and soil erosion processes in small watersheds under three different land uses, at three time scales. We investigated four small watersheds in southern Brazil: Agricultural North watershed (ANW), Agricultural South watershed (ASW), Eucalyptus watershed (EW), and Grassland watershed (GW). The SWAT (Soil and Water Assessment Tool) model was used to simulate streamflow (SF) and sediment yield (SY) at monthly, daily and hourly time scales. EW had the lowest SF and SY, whereas ANW showed the highest SY with an increase of 90% and ASW had the highest SF with an increase of 70%. The SWAT model had a satisfactory performance in all time scales and watersheds for SF and SY (NSE and R2 ≥ 0.3 and Pbias ≤ ± 39%). Overall, land use has a major impact on hydrological and soil erosion responses, and the magnitude of these processes depends on the time scale. [ABSTRACT FROM AUTHOR]

This work performs an analysis of the spatial pattern of the coffee harvested area in the Rio de Janeiro state between 1988 and 2018. To relate changes in land cover and land use with the coffee land abandonment, geographically weighted regressions (GWR) were adopted with the rates of change in forest and pasture cover, and also with changes in the size of the cattle herd. The coffee-crop area evolution identifies three behaviors: the concentration of planted area in the northwest, with constant growth after the 1990s; a remaining area in the mountainous region; and the abandonment of coffee farms in the south. Although bivariate models can't explain the changes in land cover and land use, geographically weighted regressions point to a trend of replacing coffee cover with pasturelands in the south region of the state, while eventual changes for forest cover are more likely in other regions. [ABSTRACT FROM AUTHOR]

A regional approach to the study of Brazil's beef industry is increasingly relevant as deforestation takes centre stage in policy debates worldwide. To what extent has beef production expanded toward regions hosting sensitive ecosystems such as the Amazon? Important data limitations remain to answer this question, especially regarding slaughterhouses, fundamental to the beef supply chain. This paper addresses the data gap on slaughterhouse location and history and provides novel regional analysis. We map the beef industry's evolution into Brazil's interior over the last six decades and quantify changes in market concentration between 2006 and 2016. To accomplish this, we triangulated across fiscal and animal sanitation data sources to produce the first longitudinal dataset with information on the opening and closing dates, locations, and production volumes of 2602 slaughterhouses. We show the linear movement of slaughterhouses and cattle herds to the Amazon by tracking their geographical centres of gravity. We also show the clustering pattern of slaughterhouses. Until the 1960s, all the geographical clusters were located south of the capital, Brasília. By the early 2000s, clusters north of Brasília were almost as extensive. Finally, we assessed the degree of market power that the largest beefprocessing companies possess. The results indicate that market concentration increased in regions of more recent settlement further away from the coast, and that it remained relatively stable in states near the coast (Minas Gerais, São Paulo). The results shed light on the relationship between displacement toward the Amazon and Cerrado regions and economic concentration. [ABSTRACT FROM AUTHOR]

This study aims to understand the response of the trophic state index (TSI) of a reservoir under different watershed land-use scenarios. A novel methodology was applied to the Verde River Basin in the south of Brazil, which is exploited by agricultural activity and has a reservoir for water supply. An ecohydrological model was used to calculate daily nutrient concentrations in the water system, which allowed the determination of the reservoir's TSI. The authors propose a new TSI known as TSImod, considering phosphorus, nitrogen, and chlorophyll in its determination. The results indicate that TSImod may be more appropriate for classifying highly impacted environments when compared to the index currently used in Brazil. The Verde River Reservoir was classified as mesotrophic under the current land-use scenario and eutrophic under the proposed scenarios. The framework developed in this study can be replicated in other watersheds to evaluate the impacts of land-use change on water quality. [ABSTRACT FROM AUTHOR]