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La inversión uterina es una entidad que en el área de ginecología no se presenta con mucha frecuencia; a pesar de ello, es considerada como una emergencia. La forma no puerperal se describe en situaciones relacionadas a tumores benignos o malignos del cuerpo uterino. Se presenta el caso de una paciente de 63 años que acude a consulta con cuadro clínico caracterizado por dolor en hipogastrio intenso tipo cólico y sangrado vaginal de 15 días de evolución. Al examen físico ginecológico se evidencia tumoración a nivel vaginal con tejido necrótico y coágulos. Se solicita resonancia magnética nuclear, obteniendo como diagnóstico inversión uterina, por lo que se le realiza histerectomía abdominal con evolución favorable.

The watershed is a depression on the land’s surface, which is surrounded by higher land and drained by a river and its various tributaries. The streams are the morphologic elements of a basin that help draining the runoff reaching the Earth’s surface as rainfall, into a main water course. The present research had the objective of studying the hydrologic structuring of Paraopeba River Watershed located in the state of Minas Gerais, Brazil. The watershed was divided in 66 subbasins and geomorphological characteristics were calculated, namely those relevant for the assessment of hydrology and sediment transport. The materials and methods involved a geographic information system coupled with aerial photography interpretation methods that allowed a detailed geomorphologic analysis, irrespective of the large area of Paraopeba basin. The longitudinal profiles of water courses enabled to understand the three-dimensional development of stream networks while stream directions were linked to water-resources management. The results also exposed a relationship between landscape change and dynamic interactions between the physical and material environments triggered by natural and cultural forces. The actual shape of Paraopeba River watershed depends on the flowing streams and was strongly influenced by geologic heterogeneity. The singular features and processes that created a subbasin could be related with specific physical and environmental settings, that differed from place to place, whereas different landscape types were recognized as well as different landscape regions.

The rupture of a tailings dam causes several social, economic, and environmental impacts because people can die, the devastation caused by the debris and mud waves is expressive and the released substances may be toxic to the ecosystem and humans. There were two major dam failures in the Minas Gerais state, Brazil, in the last decade. The first was in 2015 in the city of Mariana and the second was in 2019 in the municipality of Brumadinho. The extent of land use and cover changes derived from those collapses were an expression of their impacts. Thus, knowing the changes to land use and cover after these disasters is essential to help repair or mitigate environmental degradation. This study aimed to diagnose the changes to land cover that occurred after the failure of dam B1 in Brumadinho that affected the Ferro-Carvão stream watershed. In addition to the environmental objective, there was the intention of investigating the impact of image preparation, as well as the spatial and spectral resolution on the classification’s accuracy. To accomplish the goals, visible and near-infrared bands from Landsat (30 m), Sentinel-2 (10 m), and PlanetScope Dove (4.77 m) images collected between 2018 and 2021 were processed on the Google Earth Engine platform. The Pixel Reduction to Median tool was used to prepare the record of images, and then the random forest algorithm was used to detect the changes in land cover caused by the tailings dam failure under the different spatial and spectral resolutions and to provide the corresponding measures of accuracy. The results showed that the spatial resolution of the images affects the accuracy, but also that the selected algorithm and images were all capable of accurately classifying land use and cover in the Ferro-Carvão watershed and their changes over time. After the failure, mining/tailings areas increased in the impacted zone of the Ferro-Carvão stream, while native forest, pasture, and agricultural lands declined, exposing the environmental deterioration. The environment recovered in subsequent years (2020–2021) due to tailings removal and mobilization.

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.

This study investigated the collapse of B1 mine-tailings dam that occurred in 25 January 2019 and severely affected the Brumadinho region (Minas Gerais state, Brazil) socially, economically and environmentally. As regards water resources, the event impacted the Paraopeba River in the first 155.3 km counted from the dam site, meaning nearly half the main water course downstream of B1. In the impacted sector, high concentrations of tailings-related Al, Fe, Mn, P in river sediment-tailings mixtures and water were detected, as well as changes to the reflectance of riparian forests. In the river water, the metal concentrations raised significantly above safe levels. For caution, the water management authorities declared immediate suspension of Paraopeba River as drinking water source to the Metropolitan Region of Belo Horizonte (6 million people), irrespective of representing nearly 30% of all supply. In this study, the main purpose was to assess potential links between tailings distribution, river water composition and reflectance of forest vegetation, which worked out as latent variables in regression models. The latent variables were represented by numerous physical and chemical parameters, measured 4 times in 22 sites during the dry period of 2019. The modeling results suggested the release of aluminum and phosphorus from sand fractions in the mine tailings as major cause of water contamination. The NDVI changes were interpreted as environmental deterioration. Changes in redox potential may have raised manganese concentrations in surface water further affecting the forest NDVI. Distance from the B1 dam and dissolved calcium appear to attenuate deterioration. Overall, the regressions allowed robust prognoses of environmental deterioration in the Paraopeba River under low flow conditions. More importantly, they can be transposed to similar dam ruptures helping environmental authorities to decide upon measures that can bring the affected rivers to pre-rupture conditions.

The rupture of mine-tailings dams can severely contaminate rivers, because released tailings can interact with water for years keeping contaminant concentrations high. The general purpose of this study was to examine the rupture of B1 tailings dam in Ferro-Carvão stream (municipality of Brumadinho, state of Minas Gerais, Brazil), which occurred in 25 January 2019 and contaminated the main water course (Paraopeba River) with 2.8 Mm

The present study aimed to investigate the rupture of B1 tailings dam of Córrego do Feijão mine, which drastically affected the region of Brumadinho (Minas Gerais, Brazil). The contamination of water resources reached 155.3 km from the dam site. In the river channel, high concentrations of Mn, Al, As and Fe were detected and correlated to the spillage of the tailings in the river. The presence of the tailings also affected the chlorophyll-a content in the water, as well as the reflectance of riparian forests. With the increase of metal(oid) concentrations above permitted levels, water management authorities suspended the use of Paraopeba River as resource in the impacted areas, namely the drinking water supply to the Metropolitan region of Belo Horizonte. This study aimed to evaluate possible links between tailings distribution, river water quality, and environmental degradation, which worked as latent variables in partial least squares regression models. The latent variables were represented by numerous physical and chemical parameters of water and sediment, measured four times in 22 locations during the rainy season of 2019, in addition to stream flow and to NDVI evaluated in satellite images processed daily. The modeling results suggested a relationship between river flow turbulence and increased arsenic release from sand fractions, as well as desorption of Mn from metal oxides, both representing causes of water quality reduction. They also revealed increasing iron concentrations affecting the forest NDVI (greening), which was interpreted as environmental degradation. The increase of chlorophyll-a concentrations (related with turbidity decreases), as well as the increase of river flows (responsible for dilution effects), seemed to work out as attenuators of degradation. Although applied to a specific site, our modeling approach can be transposed to equivalent dam failures and climate contexts, helping water resource management authorities to decide upon appropriate recovery solutions.

The main objective of this study was to investigate the relationships between land use and future scenarios of land changes on water runoff and groundwater storage in an Environmental Protection Area (EPAs) watershed. The methodology was based on the application of the Soil and Water Assessment Tool (SWAT) hydrological modelling to investigate flow simulations in current land use and in two future scenarios (forest and pasture). The performance of goodness-of-fit indicators in the calibration (NSE = 0.82, R2 = 0.85, PBIAS = 11.9% and RSR = 0.42) and validation (NSE = 0.70, R2 = 0.72, PBIAS = -4% and RSR = 0.55) was classified as good and very good, respectively. The model accurately reproduced the inter-annual distribution of rainfall. The spatial distribution of average annual surface flow, lateral flow, and groundwater flow were different between sub-basins. The future scenario on land use change to forest (FRSE) and pasture (PAST) differed during the year, with greater changes on rainy and dry seasons. FRSE increase of 64.5% in area led to decreased surface runoff, total runoff, and soil water, and increased lateral flow, groundwater, and evapotranspiration. The effect of the natural vegetation cover on soil moisture content is still unclear. The hydrological model indicated the main areas of optimal spatial water flow. Considering economic values, those areas should encourage the development of government policies based on incentive platforms that can improve environmental soil and water sustainability by establishing payment for environmental services (PES).

Made available in DSpace on 2022-04-28T19:44:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-10-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação para a Ciência e a Tecnologia Inadequate pasture management causes land degradation through reduction of grass, increased presence of invasive plants or pests, compaction, erosion, and nutrient deficiency. The recognition of pasture degradation is therefore essential. Remote sensing satellite systems allow us to do so at regional-to global scales. A struggle is in progress nowadays is to improve detection accuracy and implement high-resolution surveys at farm scales using low-cost unmanned aerial vehicles (UAVs). The pasture imagery can be translated into maps of degraded pasture using the popular NDVI as diagnostic parameter, but their generation using a UAV requires a high-cost NIR sensor, while the struggle is to use low-cost UAVs equipped with RGB cameras. The first step to recognize degraded pastures using RGB cameras is to define a suitable vegetation index. Thus, the purpose of this study was to present the total brightness quotient of red (TBQR), green (TBQG), and blue (TBQB) bands. The test to the index resorted to LANDSAT-8 satellite images captured over the environmental protection area of Uberaba River basin (Minas Gerais, Brazil) in the 2017–2019 period. The images were not captured by a UAV because the equipment was not then available. The results were promising given the large detection accuracy (88.63%) of the TBQG and the high (0.965) correlation between TBQG and NDVI. Besides, the TBQ-based areas of degraded pasture (17,486.3–25,180.1 hectares) were larger than the NDVI counterparts (12,066.9 hectares). This is an additional reason to oversight degraded pastures based on the TBQs, as they seek for improved environmental compliance and economic development. Geoprocessing Laboratory Federal Institute of Triângulo Mineiro Uberaba Campus POLUS—Grupo de Política de Uso do Solo Universidade Estadual Paulista (UNESP) Regional Coordination of the Environmental Justice Prosecutor's Office of the Paranaíba and Lower Rio Grande River Basins Center for Research and Agro-environmental and Biological Technologies University of Trás-os-Montes e Alto Douro Center of Chemistry of Vila Real University of Trás-os-Montes e Alto Douro POLUS—Grupo de Política de Uso do Solo Universidade Estadual Paulista (UNESP) CNPq: 307921/2018-2 Fundação para a Ciência e a Tecnologia: UIDB/00616/2020 Fundação para a Ciência e a Tecnologia: UIDB/04033/2020

Made available in DSpace on 2021-06-25T10:24:18Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-07-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação para a Ciência e a Tecnologia The inadequate management of soils and the absence of conservation practices favor the degradation of pastures and can trigger adverse environmental alterations and damage under the terms of Brazilian Federal Law no. 6.938/1981. Based on this premise, this study aimed to estimate soil losses caused by water erosion in pasture areas using the brightness index (BI) from the annual series of Landsat 8 images in different geological formations. A specifically prepared Google Earth Engine (GEE) script automatically extracted the BI from the images. The study occurred in the Environmental Protection Area (EPA) of Uberaba River basin (Minas Gerais, Brazil). To accomplish the goal, 180 digital 500-wide random buffers were selected from 3 geologic types (60 points per type), and then analyzed for zonal statistics of USLE (Universal Soil Loss Equation) soil loss and BI in a Geographic Information System. The regression models BI versus USLE soil loss allowed estimating BI soil losses over the pastures of EPA. The model fittings were remarkable. The validation of soil loss maps in the EPA occurred in pasture phytophysiognomies through the probing of penetration resistance in 37 randomly selected locations. The results were satisfactory, mostly those based on the BI. The BI losses increased for greater resistances. Amplified losses also occurred in regions exposed to environmental land use conflicts (actual uses that deviate from land capability or natural use). Overall, the BI approach proved efficient to accurately track soil losses and pasture degradation over large areas, with the advantage of standing on a single parameter easily accessed through remote sensed data. From an environmental standpoint, this is an important result, because the accurate diagnosis and prognosis of degraded pastures is paramount to implement mitigation measures following the “polluter pays principle”, even more in Brazil where the areas occupied by degraded pastures are enormous. Federal University of Triângulo Mineiro Institute of Technological and Exact Sciences (ICTE) Federal Institute of Triângulo Mineiro Uberaba Campus Geoprocessing Laboratory Coordenadoria Regional das Promotorias de Justiça do Meio Ambiente das Bacias dos Rios Paranaíba e Baixo Rio Grande, Rua Coronel Antônio Rios, 951 Center for Research and Agro-environmental and Biological Technologies University of Trás-os-Montes e Alto Douro, Ap. 1013 Center of Chemistry of Vila Real University of Trás-os-Montes e Alto Douro, Ap. 1013 POLUS—Grupo de Política de Uso do Solo Universidade Estadual Paulista (UNESP), Via de Acesso Prof. Paulo Donato Castellane, s/n POLUS—Grupo de Política de Uso do Solo Universidade Estadual Paulista (UNESP), Via de Acesso Prof. Paulo Donato Castellane, s/n Fundação para a Ciência e a Tecnologia: UID/00616/2020 Fundação para a Ciência e a Tecnologia: UID/04033/2020

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.

Degradation is currently affecting 25% of Earth's land and 40% of Earth's agricultural land. The environmental consequences of land degradation are vast, including amplified soil losses, water quality deterioration, biodiversity decline and degradation of ecosystem services and corresponding values, especially if actual land uses disrespect capability (natural use), in which cases land is in a state of environmental conflict. The global cost of land degradation just looking to agriculture approaches US$ 500 billion/yr. Facing this terrible ecological and economic scenarios, the United Nations General Assembly adopted the “Sustainable Development Goals” in 2015, which comprise a target to combat desertification and restore degraded land. The aim is to achieve land degradation neutrality by 2030. Framework models have already been proposed to unpack this innovative concept and address its operation through the Rio Conventions. While implementing these models, which follow the response hierarchy of avoid > reduce > reverse land degradation, environmental consequences of land degradation should be compensated by sustainable land management practices that render the Earth no net loss of the land-based natural capital relative to a baseline. The ultimate goal is however to attain self sustainability whereby environmental and production potentials are supported by self-regulating processes within the system.

Made available in DSpace on 2022-05-01T10:03:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-02-25 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Universidade de Trás-os-Montes e Alto Douro Fundação para a Ciência e a Tecnologia In January 25, 2019, the B1 dam of Córrego do Feijão mine located in Brumadinho municipality (Minas Gerais, Brazil) collapsed and injected nearly 2.8 Mm3 of iron (Fe)- and manganese (Mn)-rich tailings in the Paraopeba River. This study assessed the contribution of tailings to the contamination of sediments and water by those metals. The dataset was built through daily to weekly samplings executed in the two years following the event, at 27 sites located along the Paraopeba plus 9 sites located at the confluence of main tributaries. The results evidenced a distinct contribution in the sectors “Anomalous” (8.6–63.3 km downstream from the dam) and “Natural” (115.8–341.6 km). The “Anomalous” sector presented large Fe/Al (12.2 ± 6.4) and Mn/Al (0.33 ± 0.19) ratios in sediments, thus being rich in tailings, while the “Natural” sector presented small ratios (2.4 ± 1.0; 0.06 ± 0.03) comparable to the natural sediments. A 500–700 m3/s stream flow discharge in the Paraopeba caused pronounced drops to the Fe/Al and Mn/Al ratios in the “Anomalous” sector, attributed to the mixture of contaminated sediments from the main water course with uncontaminated sediments injected by the tributaries during the event. Non-linear regressions showed Fe/Al and Mn/Al declines in the “Anomalous” sector, related with tailings mobilization downstream. The concentrations of Fe and Al in the sediments correlated positively with the corresponding concentrations in the Paraopeba water, conditioned by raising discharge rates and variations in the water pH. The contribution of tailings to the Fe correlation was demonstrated. No direct relation was established between the Mn concentrations in water and stream discharge, because manganese is associated with fine particles in the tailings that are mobilized to the water column even under low flows. The preliminary results of Seasonal Autoregressive Integrated Moving Average models predicted the return of Paraopeba to a pre-collapse condition in 7–11 years. CQVR – Centro de Química de Vila Real Universidade de Trás-os-Montes e Alto Douro, Ap. 1013 Instituto Federal do Triângulo Mineiro Campus Uberaba Laboratório de Geoprossessamento Faculdade de Ciências Agrárias e Veterinárias Universidade Estadual Paulista (UNESP) Via de Acesso Prof. Paulo Donato Castellane s/n Secretaria de Estado de Meio Ambiente e Desenvolvimento Sustentável Cidade Administrativa do Estado de Minas Gerais Rodovia João Paulo II 4143 Bairro Serra Verde - Belo Horizonte - Minas Gerais Coordenadoria Regional das Promotorias de Justiça do Meio Ambiente das Bacias dos Rios Paranaíba e Baixo Rio Grande Rua Coronel Antônio Rios 951 CITAB – Centro de Investigação e Tecnologias Agroambientais e Biológicas Universidade de Trás-os-Montes e Alto Douro, Ap. 1013 Faculdade de Ciências Agrárias e Veterinárias Universidade Estadual Paulista (UNESP) Via de Acesso Prof. Paulo Donato Castellane s/n Fundação para a Ciência e a Tecnologia: UIDB/00616/2020 Fundação para a Ciência e a Tecnologia: UIDB/04033/2020 Fundação para a Ciência e a Tecnologia: UIDP/00616/2020

Cattle grazing is a major source of income across the globe, and therefore conservation of pastures is vital to society. Pasture conservation requires the full understanding of factors contributing to their degradation, which is facilitated through panoramic analyses capable to handle all factors and capture their relationships at once. In this study, Partial Least Squares – Path Modeling (PLS-PM) was used to accomplish that task. The study area was the Environmental Protection Area of Uberaba River Basin (525 km2), located in the state of Minas Gerais, Brazil, and extensively used for livestock pasturing (51%). The selected (15) contributing factors comprised soil characteristics (e.g., organic matter, phosphorus content), runoff indicators (e.g., percentage of sand and clay in the soil), environmental land use conflicts (deviations of actual from natural uses), stream water quality parameters (e.g., oxidation-reduction potential-ORP, turbidity), and pasture conservation indicators (extent of degraded pasture within a pre-defined buffer). These measured variables were assembled into 5 conceptual (latent) variables to form the PLS-PM model, namely Groundcover, Pasture Conservation, Surface Runoff, Environmental Land Use Conflicts and Water Quality. The results elected Groundcover as prominent contributor to Pasture Conservation, because of its largest regression (path) coefficient (β = 0.984). The most influent measured variable was organic matter. Surface Runoff (β = −0.108) and Environmental Land Use Conflicts (β = −0.135) contribute to pasture degradation. The role of conflicts is, however, limited to predefined areas where the deviations of actual from natural uses are more expressive. Pasture Conservation contributes unequivocally to improved Water Quality (β = 0.800), expressed as high ORP. The PLS-PM model was free from multi-collinearity problems and model fits (R2) were high. This gives us confidence to implement conservation measures and improved management techniques based on the PLS-PM results, and to transpose the model to other areas requiring pasture quality improvements.

Water resources are fundamental for the social and economic development of a country and sustainability is the best approach to treat water-related problems. Therefore, sustainability studies of water resources are deemed urgent. Sustainability analysis methods should enable space-temporal monitoring, decision-making, and development of policies necessary for water governance. Furthermore, sustainability analysis methods should also integrate environment and socioeconomic variables into a single system. In this context, this study aimed to assess the water sustainability conditions of the River Grande Basin (BHRG), Brazil, before the implementation of the Integrated Water Resources Plan (IWRP), using the Barometer of Sustainability tool (BS). The River Grande basin was in an &ldquo, almost unsustainable&rdquo, condition and under high environmental stress. A significant imbalance between environmental and human well-being in the system was also observed. To achieve an acceptable sustainability condition, it is thus necessary to improve the environmental quality of the area. Among the priority thematic area, native vegetation recovery was the most urgent. Overall, the sustainability study based on the BS not only facilitates comprehension regarding environment and human interrelationships, but also provide references for policy formulations and water management.

Made available in DSpace on 2018-12-11T16:47:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-07-01 The “polluter pays principle” (PPP) has been looked at from the perspective of legal values and technical principles, namely of soil science, to evaluate the acceleration of soil erosion and the consequent development of degraded areas in the Uberaba River basin (area: 2419 km2), state of Minas Gerais, Brazil. Having accomplished this goal, the study highlights the importance of PPP for the conservation of soil and development of an ecologically equilibrated environment. The diagnosis of degraded areas was based on the coupling of a Geographic Information System with soil loss, land use conflict and tolerance to soil loss models, and revealed a preoccupying situation because an extension of approximately 905 km2 (1/3 of the basin) has been considered in advanced state of degradation potentially causing environmental damage (e.g., decline of soil fertility and hence crop production, negative impacts of soil particles export on stream and lake water quality and biodiversity of riverine ecosystems). Facing this problem, a legal framework standing on doctrinaire principles, federal laws and the Brazilian Constitution has been proposed whereby the protagonists of soil degradation are called to assume responsibility as well as the costs of repairing this negative condition. Although the study has been carried out on a specific country under pre-defined settings, the rationale behind the proposals can easily be transposed to other scenarios because the scientific methods on which soil degradation has been defined and mapped are generally applicable, while the suggested legal values are currently applied to many regions on the planet. Promotoria de Justiça do Ministério Público do Estado de Minas Gerais UNESP—Universidade Estadual Paulista Campus de Jaboticabal Estado de São Paulo Instituto Federal do Triângulo Mineiro Uberaba Estado de Minas Gerais Centro de Investigação e Tecnologias Agroambientais e Biológicas Universidade de Trás-os-Montes e Alto Douro, Ap 1013 Centro de Química de Vila Real Universidade de Trás-os-Montes e Alto Douro, Ap 1013 UNESP—Universidade Estadual Paulista Campus de Jaboticabal Estado de São Paulo

Riparian vegetation represents a protective barrier between human activities installed in catchments and capable of generating and exporting large amounts of contaminants, and stream water that is expected to keep quality overtime. This study explored the combined effect of landscape composition and buffer strip width (L) on stream water quality. The landscape composition was assessed by the forest (F) to agriculture (A) ratio (F/A), and the water quality by an index (IWQ) expressed as a function of physico-chemical parameters. The combined effect (F/A &times, L) was quantified by a multiple regression model with an interaction term. The study was carried out in eight catchments of Uberaba River Basin Environmental Protection Area, located in the state of Minas Gerais, Brazil, and characterized by very different F/A and L values. The results related to improved water quality (larger IWQ values) with increasing values of F/A and L, which were not surprising given the abundant similar reports widespread in the scientific literature. But the effect of F/A &times, L on IWQ was enlightening. The interaction between F/A and L reduced the range of L values required to sustain IWQ at a fair level by some 40%, which is remarkable. The interaction was related to the spatial distribution of infiltration capacity within the studied catchments. The high F/A catchments should comprise a larger number of infiltration patches, allowing a dominance of subsurface flow widespread within the soil layer, a condition that improves the probability of soil water to cross and interact with a buffer strip before reaching the stream. Conversely, the low F/A catchments are prone to the generation of an overland flow network, because the absence of permanent vegetation substantially reduces the number of infiltration patches. The overland flow network channelizes runoff and conveys the surface water into specific confluence points within the stream, reducing or even hampering an interaction with a buffer strip. Notwithstanding the interaction, the calculated L ranges (45&ndash, 175 m) are much larger than the maximum width imposed by the Brazilian Forest Code (30 m), a result that deserves reflection.

The riparian buffer width on watersheds has been modified over the last decades. The human settlements heavily used and have significantly altered those areas, for farming, urbanization, recreation and other functions. In order to protect freshwater ecosystems, riparian areas have recently assumed world recognition and considered valuable areas for the conservation of nature and biodiversity, protected by forest laws and policies as permanent preservation areas. The objective of this work was to compare parameters from riparian areas related to a natural watercourse less than 10 m wide, for specific purposes in Law No. 4761/65, now revoked and replaced by Law No. 12651/12, known as the New Forest Code. The effects of 15, 30 and 50 m wide riparian forest in water and soil of three headwater catchments used for sugar cane production were analyzed. The catchments are located in the Environmental Protection Area of Uberaba River Basin (state of Minas Gerais, Brazil), legally protected for conservation of water resources and native vegetation. A field survey was carried out in the catchments for verification of land uses, while periodical campaigns were conducted for monthly water sampling and seasonal soil sampling within the studied riparian buffers. The physico-chemical parameters of water were handled by ANOVA (Tukey&rsquo, s mean test) for recognition of differences among catchments, while thematic maps were elaborated in a geographic information system for illustration purposes. The results suggested that the 10, 30 or even 50 m wide riparian buffers are not able to fulfill the environmental function of preserving water resources, and therefore are incapable to ensure the well-being of human populations. Therefore, the limits imposed by the actual Brazilian Forest Code should be enlarged substantially.

In the Uberaba River basin (state of Minas Gerais, Brazil), pastures for livestock production have invaded areas of native vegetation (Cerrado biome), while already existing pastures were invaded by crop agriculture, with an expansion of sugar cane plantations in the most recent years. In some areas of the basin, these land use changes were classified as environmental land use conflicts because the new uses were not conforming to land capability, i.e. the soil's natural use. Where the areas in conflict became dense, some soil properties have changed significantly, namely the organic matter content and the exchangeable potassium concentration, which have decreased drastically (5 kg/m3 per 10% increase in the conflict area) threatening the fertility of soil. Besides, these changes may have triggered a cascade of other environmental damages, specifically the increase of soil erosion and the degradation of water quality with negative impacts on aquatic biodiversity, related to a disruption of soil organic matter structural functions. Because half the Uberaba catchment has been considered is a state of accentuated environmental degradation, not only caused by environmental land use conflicts, conservation measures have been proposed and requested for immediate implementation across the watershed.

O presente trabalho, sem a pretensão de exaurir o tema, faz uma análise sobre as modificações levadas a efeito pela Lei Federal nº 12.651 e Medida Provisória 571, ambas de 2012, as quais revogaram a Lei Federal n° 4771/65 - Código Florestal. Procura-se esclarecer que a lei revogada (4771/65) trazia conceitos ecológicos e definia serviços ecossistêmicos, especialmente, das chamadas áreas protegidas. Os conceitos da Lei Federal n° 4771/65 foram baseados nos conhecimentos científicos da época, os quais permanecem atualmente no meio acadêmico e científico. A legislação superveniente, olvidando-se de tais conceitos e definições, inovou o mundo jurídico de forma nefasta ao meio ambiente. A nova legislação que está denominada "Novo Código Florestal" despreza, por completo, os conceitos técnicos e se traduz em grave retrocesso ambiental afetando todos os Biomas do país e como corolário às atividades desenvolvidas, inclusive as desempenhadas pela agricultura familiar.