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Organic carbon performs essential functions in soils, which act as sources or sinks of atmospheric organic carbon. Agricultural management affects the carbon cycle in the soil, with effects on climate change. One of the crops most vulnerable to climate change is coffee. Brazil is the world’s largest coffee producer, with a predominance of management under a conventional system, with sloping terrain and the absence of conservationist practices. The absence of conservationist practices increases in soil loss rates due to water management and carbon emissions, as well as a reduction in coffee production. This paper intended to estimate soil and organic carbon losses by RUSLE in coffee farms in southern Minas Gerais, south-eastern Brazil. Data were obtained from fieldwork, laboratory analysis, and cartographic products. The results indicated, exclusively for coffee crops, soil and carbon losses between 7 and 32 Mg ha−1 year−1 and 87 and 460kg ha−1 year−1, respectively. However, the highest soil losses occurred on sloping terrains with eucalyptus plantations located downhill, and the lowest losses occurred on flat land with native forests. Organic carbon losses were linked directly to soil losses, as a result from the land practices, slope and agricultural management adopted. These results can be used for the planning and priority definition of areas needing conservationist practices, such as green manuring, planting in contour and maintaining of vegetation between coffee rows, which are already used in some sites of the study area. [ABSTRACT FROM AUTHOR]

Soil organic matter (SOM) plays a crucial role in soil health, fertility, and carbon cycling, making its accurate estimation essential for sustainable agriculture and ecosystem management. However, the quantification of SOM is fraught with methodological challenges that can introduce variability and uncertainty into assessments. Traditional techniques may lack specificity and accuracy, while advanced methods pose challenges related to calibration and standardization. The selection of an appropriate method is critical and requires careful consideration of soil characteristics, land use, and research objectives. This article reviews the key methodological challenges associated with estimating soil organic matter, aiming to provide an understanding of the complexities involved, and provides insights on the latest instrumentation for SOM measurements. [ABSTRACT FROM AUTHOR]

The Cantareira System is one of the largest water supply systems in the world, supplying about half of the water consumed by 22 million inhabitants in the Metropolitan Region of São Paulo, in southeastern Brazil. In this scenario, in view of climate change, silting is a serious environmental threat and a major challenge to the sustainability of water reservoirs. Therefore, identifying the provenance of sediments is an essential tool to support soil conservation policies, slowing erosion processes and mitigating the deposition of sediments in water reservoirs. Thus, this study aimed to model soil losses—sediment production, by water erosion in the Cantareira System, based on the RUSLE model—Revised Universal Soil Loss Equation, GIS—Geographic Information System and SR—Remote Sensing. The work was conducted on data obtained from online platforms of Brazilian public institutions. The results indicate an average rate of soil loss of 13 Mg ha−1 yr−1, which corresponds to an annual loss of 3 million tons, of which 22% reaches water bodies. The data also show that: (1) in 66 % of the Cantareira System, soil losses are below the soil loss tolerance limits, and, in 34% of the region, water erosion is compromising the sustainability of water and soil resources; (2) the areas with the greatest soil losses are predominantly located in planted forests, agricultural crops and non-vegetated areas; and (3) sectors with high rates of soil loss require the adoption of conservationist practices aimed at reducing sediment production rates and thereby increasing supply and improving water quality. [ABSTRACT FROM AUTHOR]

Dam siltation has become a serious problem in arid and semi-arid countries under climate variability, where soil erosion and siltation represent a major challenge that face the industry of dams. In Morocco the policy of dam construction is one of the main keys in sustainable development, but unlikely, the dam siltation caused by soil erosion still present a big constraint. This study was carried out in the sub-basin of Tillouguite upstream the Bin El Ouidane dam in the High Atlas, in the region of Beni Mellal Khenifra, Morocco. The study aims to estimate the production of erosion material: soil losses, and the real soil losses rate - sediment yield, in Bin El Ouidane dam, using a combination of IntErO model - Intensity of Erosion and Outflow, GIS - Geographic information System and RS - Remote sensing. The study requires data which are collected from meteorological stations, soil data analysis, satellite images and observations during field missions. As a result, the production of erosion material in the Tillouguite sub-basin is estimated at 10,015,354 m³yr-1, the coefficient of the deposit retention is estimated at 0.283, and the real soil losses rate is around 2,838,489 m³yr-1. Given that the specific real soil losses rate is estimated at 910.02 m³km²yr-1, and based on Gavrilovic classification, the sub-basin of Tellouguite is considered with a high potential of soil erosion risk, due to large bare land, and the steep land slope in the sub basin - factors that affect the storage capacity of Bin El Ouidane Dam. All the findings are a measurable indicators that are inviting policy makers to initiate appropriate measures for the protection of land degradation, all in line with the sustainable development policies in Morocco. [ABSTRACT FROM AUTHOR]

In recent decades, the frequency and severity of wildfires have increased, especially in the Mediterranean Basin. Aside from their direct effects, accelerated soil erosion is observed in fire-affected areas due to the destruction of vegetation. The 2021 Greece megafires were one of the country's major ecological disasters, destroying over 125,000 hectares of forest and agricultural land. The present study aims to quantify the effects of selected wildfire events on erosion dynamics over the 2021 fire season. To accomplish the goals of the current research the RUSLE erosion prediction model was implemented using readily available earth observation (EO) data. The results demonstrated a shift to the erosion hazard from very low and low (pre-fire) to severe and very severe (post-fire), in all cases. In particular, the increase in potential erosion, expressed in t ha-1 y-1, was found to be equal to 98.5, 65.9, 57.0, 56.3, 51.6 and 35.6 for the Gytheio (Laconia), Schinos (Corinthia - West Attica), Northern Evia, Ancient Olympia - Gortynia (Ilia), Vilia (Western Attica) and Varympompi (Attica) regions, respectively. Moreover, the spatial distribution of post-fire soil erosion rates provides sufficient information for the identification of the erosion prone-areas and the corresponding emergency rehabilitation treatments. [ABSTRACT FROM AUTHOR]

Water erosion has radically affected the productive capacity of soils, especially in regions with a tropical climate, causing environmental and social damage, such as reduced agricultural productivity and siltation of water bodies. The objective of this research was to estimate soil losses with using the IntErO model - Erosion Potential Method in the River Machado Watershed (MRW), South Minas Gerais State (Brazil), with the idea to identify areas of increased soil losses due to water erosion, contributing with the research activities to the environmental planning in order to prevent land degradation. The Machado River basin was selected as study area because it is an important Sustainable Use Conservation Unit in Minas Gerais, which has abundant water resources, rich biodiversity, and intensive agricultural production. The estimated soil losses for the year 2020 were calculated, using the IntErO model - Erosion Potential Method, in a Geographic Information System (GIS) environment. The MRW presented an average soil loss of 18.2 Mg ha-1 yr-1, and a total of about 2 million tons per year. In about 85% of the watershed, soil losses were greater than the tolerable limits, what leads to the conclusion that there is a need to adopt a comprehensive soil conservation management plan to reduce water erosion. The highest average soil losses occurred in areas of exposed soil as well as sporadic agricultural and pasture, and are concentrated in the southern sector of the studied area. The results obtained can support the environmental planning aimed at the conservationist use of the soil in the MRW. [ABSTRACT FROM AUTHOR]

Forest fires have increased a lot in Brazil in recent years, causing air pollution, increased soil erosion processes with production of sediments, emission of greenhouse gases and overloading public health services, with severe environmental and socioeconomic losses. Therefore, the development of new analysis and mapping technologies for areas affected by fires is necessary and essential in this context of accentuated expansion of forest fires. Research monitoring flights were performed with an unmanned aerial vehicle to obtain RGB aerial images of a fragment of native forest affected by fire in July 2019. Thus, subareas were defined to define mapping patterns that can serve as algorithms for remote detection of areas affected by fires. Afterwards, land use were generated to monitor the evolution of the natural process of regeneration of the forest fragment. The studies identified that 0.77 ha was affected by the fire and that from August to November of the same year, the area was completely regenerated, and all remnants of the forest fire were eliminated. Thus, the work explains a strategic alternative for reducing, combating, and monitoring forest fires. Furthermore, it also contributes as a tool for the preparation of recovery plans for areas impacted by forest fires. [ABSTRACT FROM AUTHOR]

Deltaic systems possess singular morphology and represent a portion of the Brazilian large fluvial systems, with complex dynamics and mouths located at the Atlantic Ocean. Landscapes generated are occupied by diverse human activities over the coast and depend on a certain degree of dynamic equilibrium to its maintenance. The mouth of Jequitinhonha River, located at the extreme South of Bahia state, has suffered great transformations over the last decades, causing coastal erosion processes due to fluvial discharge reduction, thus changing the local dynamic. So, to understand the preterit deltaic dynamic and the possible agents of the current changes, we proposed an approach utilizing grain size and Optically Stimulated Luminescence (OSL) of the deposits by the river mouth, with the processes currently demonstrated. The main results point to mixed depositional environment over the sampling points and additionally in depths, demonstrating cyclicity of depositional agents and energy. Depositional ages obtained were 2.72 ± 0.23 (Ky) for the left riverbank, 1.1 ± 0.15 (Ky) for the right riverbank, and the youngest deposit located at the front island, with absolute dating of 0.555 ± 0.065 (Ky). The results evidence a tendency of coastal progradation during the last thousands of years, prior to anthropic interventions which diminished and regulated fluvial discharge of Jequitinhonha River, resulting in advancement of local coastal erosive processes. [ABSTRACT FROM AUTHOR]

Brazil is a country that has a vast territory and contains many natural landscapes features and immense variety of rocks, shapes and structures of great aesthetic and scientific value. Geosites are areas that have numerous geological potentials, where these characteristics are notable from a scientific, didactic or touristic point of view. In this sense, this work carried out a cataloguing of geosites in the municipality of Conceição da Aparecida, in the south of Minas Gerais state aiming at the geoconservation of the geological heritage, the balanced use of natural resources and the identification of geosites. The lands of the study area belong to several units of the crystalline basement entitled Campos Gerais Formation, Carrancas Group, Petunia Complex, Varginha-Guaxupé Complex and Andrelândia Complex composed essentially by gneissic rocks. The development of this work consisted in the construction of a qualitative base on the studied area from the analysis of topographic maps, the use of GIS and later field activity, laboratory analysis and the elaboration of the results. In this way, the relationship between man and nature can be evidenced from the proposals for geoconservation and the identification of these areas for future generations. Thus, the integrity of nature and the best quality of life for man will be maintained. he scientific and local community will be informed about the issues of geographic space, enabling investments and better management practices in the area. [ABSTRACT FROM AUTHOR]

Forest canopy gaps are an important indicator of ecosystem dynamics. Gap sizes can vary because of several agents, and the spatial distribution is related to abiotic factors. The interest in the study of this forest attribute is old, but the difficulties to detect these areas in situ and with the use of satellite imagery hinder this research approach. Thus, we explore the use of high spatial resolution images obtained with RGB boarded in a multirotor unmanned aerial vehicle (UAV) to evaluate the best method to mapping the forest canopy gaps in Brazil. For this, were utilized the pixel- and object-based approaches, and the algorithms Random Forest (RF) and Support Vector Machine (SVM). The results showed that the ortophotomosaics can overcome the disadvantages of study the forest canopy gaps from conventional methods and reduce the complexity and costs to obtain reliable data of forests remnants. The RF and the pixel-based classification were the best combinations, with an overall accuracy (OA) of 93% in the period of study. However, the SVM presented a satisfactory accuracy to classify the forest canopy gaps, with the precision of user (PU) ranging from 86% to 98% and measure F from 85% to 96%. Therefore, was confirmed the potential of low-cost UAVs boarded with RGB sensors in this research proposal, and the results are promising for future studies. [ABSTRACT FROM AUTHOR]

Smart management (SM) in different aspects of our planet earth is an emergence tool for today's world. Since the watershed is a basic unit for all agricultural, environmental, and socioeconomic researches and developments, so SM practicing at the watershed scale is critical. In this sense, SM in a watershed scale could be introduced as connectedness of the new Information and Communication Technologies (ICT) into watershed management practices to provide added value in the better decision making or more efficient exploitation operations and management. In this way, different ICT solutions such as precision equipment, the Internet of Things (IoT), sensors, geo-positioning systems, Big Data, unmanned aerial vehicles, and robotics need to be adapted by watershed stakeholders viz. the residents, farmers, experts, land planners, and managers, as well as the decision- and policy-makers. The smart watershed management (SWM) is associated with almost every luxury in our life and included all principles and concepts of smart water management, smart farming, smart city development, etc. It is essential to choose appropriate smart technologies that could be possible by comparing regular and novel technologies, balancing customary with green infrastructures, combining regional and universal knowledge, customizing options from abroad to regional situations, allocating with ecological and societal impressions of the substitute technologies. Altogether these decisions have need of technology appraisal and assessment tools and sound watershed governance to ensure pellucidity and comprehensiveness. It is challenging to ensure the proper utilization of watershed resources. However, proper implementation of smart technologies in the watershed will surely make our lives convenient and conserve our valuable resources. SWM can provide significant environmental and economic benefits. [ABSTRACT FROM AUTHOR]

Soil losses from water erosion jeopardize agricultural sustainability and food security for current and future generations. The research aimed to evaluate the application of the Erosion Potential Method by the Intensity of Erosion and Outflow - IntErO program in a karst watershed in a region with typical savanna climate in the northeast of the State of Goiás, Brazil. Input data were adapted according to the corresponding characteristics of tropical regions. The results indicated that the Extreme watershed has a value of 0.62 in the index (0 to 1) which defined the strength of the intensity of erosion. The river basin belongs to the category 3 of destruction with moderate erosion intensity, which indicates processes of surface erosion in the largest area of the hydrographic basin, and annual soil loss of 480.60 m³ km² yr-1. According to the IntErO model calculations 16% of the eroded material reaches the outflow of the hydrographic basin, and 84% of these sediments are deposited within the Basin, inside the surface and underground caves and galleries of the karst. Calculations by the IntErO model with the Erosion Potential Method in its algorithm proved to be valuable tool in evaluating the production of sediments in tropical soils, especially in evaluating different scenarios after establishing the inputs database for Brazil and will serve as a good starting point for future evaluations. [ABSTRACT FROM AUTHOR]

Water erosion is a major cause of soil degradation worldwide. This natural phenomenon has been continually accelerated by anthropogenic activities, with constants increase of soil losses. The main objective of this study was to apply the Modified Universal Soil Loss Equation (MUSLE) model to estimate soil loss in rainy events during one year period. The total study was conducted between August 2017 and July 2019 in coffee growing areas located in the Serra da Mantiqueira, Southern Minas Gerais, Brazil. Most of the factors used for the MUSLE equation were determined from Geographic Information Systems. The results showed that soil losses ranged from 53.40 to 28.37 Mg in both areas depending on the land use and 33.12 and 23.82 Mg related to the soil classes. The largest soil losses were estimated to exposed soils in eucalyptus without conservationist practices, in the highest slopes and in Haplic Cambisol (CX). It was concluded that the conservation management practices correlated to anthropic activities adopted in the coffee crop contributed to the reduction of soil losses and maintenance of edaphic conditions. [ABSTRACT FROM AUTHOR]

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Water erosion is one of the main degradation processes of tropical soils. In steepest areas with coffee cultivation, the erosion rates are intensified and could reach levels above the Soil Loss Tolerance Limits (T). Thus, the objective of this work was to evaluate the susceptibility to water erosion in steepest areas under predominant coffee cultivation using the Revised Universal Soil Loss Equation (RUSLE) and compare the results to T limit. The research was carried out at the Ribeirão José Lúcio subbasin located in Conceição do Rio Verde Municipality and the Ribeirão São Bento subbasin located in Cambuquira Municipality, both in South of Minas Gerais State, Brazil. The parameters involved in the RUSLE and T calculations were determined from the physical and edaphoclimatic characteristics of the subbasins. The total soil loss of the Ribeirão São Bento subbasin was 1,032 Mg year-1, while the Ribeirão José Lúcio subbasin present an erosion rate of 5,014 Mg year-1 with 13.16% and 7.90% of the areas above the T limits, respectively. We found the highest losses in steepest and exposed soil areas, which should be prioritized in the adoption of conservation management practices, seeking to minimize water erosion, and ensuring the long-term sustainability of agricultural production. The RUSLE model is a fast, simple, and inexpensive tool that contributes to the assessment of soil conservation in hydrographic subbasins. [ABSTRACT FROM AUTHOR]

In tropical regions, water erosion is the process responsible for the redistribution and the loss of soil organic matter (SOM). Modelling can provide a diagnosis of the dynamics of SOM in agricultural production systems, and assist the proposing of conservationist measures. Therefore, this work aimed to estimate SOM losses due to water erosion in an agricultural production system, through the use of modelling techniques. The study area corresponding to the Santo André Farm, located in south-eastern Brazil. The area of the farm is around 75 ha, and the main agricultural product is coffee (78%). The modelling was performed based on the SOM content of the area, and the estimated soil losses, according to the Revised Universal Soil Loss Equation. To the SOM determination, soil samples were collected at 20 points, distributed over the area, in the surface layer (0-20 cm), in March 2018. The parameter acquiring and the data analysis were performed using remote sensing techniques and a Geographic Information System, which was also used to interpolate the SOM content, through the use of the ordinary kriging. The organic matter content on the farm ranged from 1.20 to 2.46%, while the average soil loss was 25.70 Mg ha-1 year-1 , with higher erosion rates in steepest sites. The estimated loss of total organic matter at 31.87 Mg year-1 , with an average of 0.42 Mg ha-1 year-1 . The observed results reveal the need to implement conservationist management measures to reduce soil losses, and the consequent SOM losses. [ABSTRACT FROM AUTHOR]

This research evaluated the effects of agriculture on hydrosedimentological dynamics in the city of Ribeirão Preto in the State of São Paulo, Brazil. Physical and chemical analyses of the soils of the Ribeirão Preto hydrographic sub-basin were carried out. A water erosion susceptibility map was generated using the Revised Universal Soil Loss Universal Equation as well as water level and potentiometric depth maps of the studied region. Using geophysical data, a local three-dimensional geological model was prepared that clearly differentiates the outcrop regions of the Guarani Aquifer System. The research results indicate that the key reasons for hydrosedimentological changes under intensified erosion processes are conventional management and forest fragmentation, which cause soil losses above the region's average tolerance limit of 8.5 Mg ha-1 year-1. Apart from soil damage, the calculated soil loss of about 1 million tons per year leads to a high risk of contamination in the Guarani Aquifer System. In regions located north of Ribeirão Preto, where the Guarani Aquifer System is shallowest, the risk of contaminants diffusing through agriculture is very high. In this context, modelling hydrosedimentological dynamics is of great importance as it enables accurate evaluation of the natural susceptibility of the aquifer to diffuse contamination. It also helps to identify sites that exceed the tolerance limit for soil loss, which are critical for conservation. However, there are no safe levels of soil loss, and attention should be paid to all areas that have soil loss values above what is considered natural. Soil losses for areas in forests were calculated as 0.03 Mg ha-1 year-1, which is well below the average for land under agricultural use (2.03 Mg ha-1 year-1). The results of this research reveal critical hydrosedimentological dynamics in the studied area that affect both the quantity and quality of the water of the Guarani Aquifer System. [ABSTRACT FROM AUTHOR]

Municipality master plan approach to the expansion processes of human activities is presently essential once poor and badly planned use of natural resources cause direct or indirect impacts on the quality and quantity of groundwater resources. Concerning the problem of contamination of this resource, the analysis of land use and coverage integrated to physical variables can contribute to improve perception of the problem. In this paper, a Chart of Groundwater Resources Potential Vulnerability to Contamination at the Municipality of Alfenas (849.97 km2), southern Minas Gerais State, Brazil, was developed. Multicriteria analysis was applied supported by decision matrices and overlapping imagery, which classified potential vulnerability to contamination in the levels: extreme, high, moderate, low and negligible. The matrices are characterized by overlapping and comparing environmental features and human actions in Geographic Information System. Results showed that the areas classified as of moderate or extreme potential vulnerability correspond to, respectively, 51.16% and 23.38% of the study area and must be a major issue for mitigation actions of their potential vulnerabilities. [ABSTRACT FROM AUTHOR]

In the state of Rondônia, deforestation, and inadequate soil use and management have intensified the water erosion process, causing degradation of agricultural land. Modeling is a tool that can assist in the adoption of targeted and effective measures for soil and water conservation in the region. In this context, the objective of the research was to model soil losses due to water erosion in the state of Rondônia using the Revised Universal Soil Loss Equation (RUSLE). The parameters related to rain erosivity, relief, erodibility, and soil cover, as well as the conservation practices of the state of Rondônia, were considered. The modeling steps were performed with the aid of the Geographic Information System. Results were validated with data of total sediments transported with water discharge. The estimated total soil loss was about 605 million tons per year, corresponding to an average loss of 22.50 Mg ha-1 year-1. In 19% of the state, the erosion rate was higher than the soil loss tolerance(T), and these areas should be prioritized for adopting measures to mitigate the erosion process. The RUSLE underestimated the generation of sediments at 0.56 Mg ha-1 year-1, which corresponds to an error of 18.60%. Results obtained can assist in the development of different soil use and management scenarios and provide options for policymakers to encourage soil conservation in the state of Rondônia. [ABSTRACT FROM AUTHOR]