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In Brazil, since 2013 the Southeast region has been dealing with recurrent hydric stress resulted from the prolongation of the dry season, whose tendency is to be more dramatic in the function of climate change. The situation is more critical in some areas, including Cordeirópolis, projecting a reduction of 50%–100% in water availability in the next 15 years, demanding urgency in water availability-use balance. Considering the significant presence of small Geographic Isolated Wetlands (GIW) in the region, it is crucial the recognition of the link between wetlands and hydrology in the catchment since these ecosystems store rainwater and can act as aquifer recharger zones. The objective of this study is to evaluate the effectiveness of non-invasive methods, such as UAV-mapping and DC resistivity, and low-invasive (in situ hydraulic conductivity) to unveil the hydrological ecosystem services of a GIW in terms of surface and groundwater. From the high-resolution orthomosaic and digital elevation model, three compartments were qualified and quantified; (i) current wetland, (ii) Flooding area and, (iii) Potential wetland expansion. From the DC resistivity, the interaction between surface water and groundwater was identified, indicating the presence of a shallow saturated only beyond the perimeter of the current wetland as a possible result of land-use conversion or climate change. In addition, the local igneous intrusion comprises the connection between shallow/surface waters and deep aquifers made by fractures. Thus, the association of both methods showed high applicability concerning the identification of GIW superficial hydrological functions (UAV) and the system's subsurface dynamic (DC resistivity).

The inland wetlands can perform the storage of water on the surface and the recharge of aquifers. Even a small wetland can work as a local point of water infiltration, influencing and sustaining the hydrodynamics in the hydrology landscape. These zones have complex mechanisms, as they integrate soil chemical and physical characteristics, and relate both surface and groundwater systems. The study area is an inland wetland located in the Ecological Station of Itirapina, São Paulo State (Brazil). The present work aims to unveil the relationship between hydrodynamics and pedological architecture through a detailed study that combines hydraulic conductivity tests in situ, geophysical method of electrical resistivity (Electrical Resistivity Tomography technique, ERT), and morphological soil descriptions aiming the validation of the ERT and hydraulic conductivity surveys. Two-dimensional (2D) and pseudo-three-dimensional (3D) ERT have been used to investigate the water flow in the subsurface, the pedological architecture that keeps the wetland hydroperiods, and the link between surface water and groundwater that can set a recharge capacity. The results showed areas with distinct surface patterns related to the density of vegetation cover and water infiltration. The lower infiltration areas are characterized by the presence of a perched water table in grassy areas while higher infiltration is associated with exposed topsoil. ERT 2D and pseudo-3D identified these areas as zones with a connection between soil-water and groundwater systems. Hydrodynamics in the flat plateau is associated with the geochemical evolution of soil cover due to the structural complexity acquired by the iron crust dissolution (laterite) which has sustained the relief. Future studies concerning inland wetlands need to be carried out to certify the role of soil-landscape in the water cycle in the Savanna biome.

The pasture is an important economic activity in the brazilian Savannah. From the 1970s and 1980s, the implementation of the programs to improve the productivity of pastures, was introduced grasses, especially Brachiaria. When handled properly, the pasture is an efficient method to contribute to carbon sequestration and to the mitigation of concentrations of greenhouse gases in the atmosphere, which are dependent to the time of the land-use and the properties of each soil type. The microregion of Uberlandia in Triangulo Mineiro (MG) is traditionally linked to the pasture. However, the geological and natural soil conditions and climate are factors that can accelerate soil degradation when pasture is not handled properly. The objective of this article was to compare the changes of soil properties and the incorporation of C in covered areas [1] natural brazilian Savannah, [2] mixed system initially converted to agricultural use and the last 15 years of pasture, and [3] pasture cultivated with 30 years of implantation. The results show the influence of the land use on organic matter dynamics, and evaluate the potential degradation of soil by the activity, management and time of land use.

Os solos do Cerrado sofrem impactos resultantes da substituição da vegetação original em sistemas agrícolas traduzidos na forma de desequilíbrios nos estoques e natureza do carbono. A região do Triângulo Mineiro vem sendo intensamente desmatada por ser uma área pioneira de expansão do agronegócio e apresenta sérios problemas relacionados à erosão do solo. Esta pesquisa teve como objetivo avaliar as mudanças na quantidade (Ctotal) na natureza (δ13C) do carbono do solo após conversão do cerrado denso em áreas com diferentes usos agrícolas (pastagem, soja e rotação soja/milho), manejos (sistemas convencionais e plantio direto). Os resultados mostraram que as mudanças nos valores relacionados ao uso e manejo são determinados também pelas características texturais dos solos formados pela alteração de litotipos distintos. Dentre os diferentes usos e manejo, o maior enriquecimento da taxa de carbono foi determinado na área com soja/milho no sistema de plantio direto em solo argiloso e o maior empobrecimento em pastagens não manejadas em solos desenvolvidos da alteração do arenito das Formações Adamantina e Marília. Estes estudos são úteis para serem usados como indicadores de qualidade para a conservação ambiental.

The Brazilian savannah (cerrado) is an area of expansion of agribusiness. Among the various environmental changes related to deforestation of the savannah stand out impacts related to soil organic matter such as the imbalances in stocks and the changing nature of soil organic carbon. The objective of these study was to evaluate changes in nature (δ13C) and quantity (C%) of soil carbon after conversion of the dense savannah vegetation in areas under different lan duses (pasture, soybeans, corn / soybean rotation), management (conventional and zero tillage) developed in soils with different textural characteristics. The results showed that the average data set of non-managed grazing was the most distanced from the value obtained in cerrado soil. Another factor that determined the lowest concentrations of organic carbon was the presence of sandy soil. The results showed that the carbon C4 grasses in areas occupied by pastures, with or without management, replaced the original C3 carbon originated by cerrado. In the areas of conventional tillage, and no-tillage soybean, and consortium soybean/corn, no clear trend of impoverishment or enrichment of carbon and the carbon substitution as well as the incorporation of different nature of the carbon could be found.

Na região sudoeste da Amazônia brasileira, foi realizado um estudo detalhado da cobertura pedológica em uma toposseqüência representativa da paisagem regional, caracterizada por baixos platôs com depressões topográficas. Os resultados indicaram que os processos pedogenéticos podem ser considerados como responsáveis pelo rebaixamento topográfico e mudanças da paisagem natural. O principal fator envolvido neste processo de transformação é a expansão remontante da hidromorfia, a partir das depressões topográficas desenvolvidas nas superfícies dos platôs. Este processo envolve transformações e degradações internas na matriz do solo acarretando em modificações na estrutura, composição química e diminuição do volume do solo.In the Southwestern Brazilian Amazon, a detailed study on the pedological cover of a representative toposequence for the region, characterized by lowered plateaus with topographic depressions, was carried out. The results indicated that pedogenic processes can be considered to be responsible for topographic smoothing and changes of the natural landscape. The main factor involved in this transformation process represents the upwards expansion of hydromorphic soil conditions from the topographic depressions developed in lower parts of the plateaus. This process includes internal transformations and degradations of the soil matrix leading to changes in soil structure, chemical composition and, diminishment of the original soil volume.

A mesorregião do Triângulo Mineiro/Alto Paranaíba recoberta originalmente pela vegetação de Cerrado vem sendo fortemente desmatada por ser uma área pioneira de expansão do agronegócio. Dentre as várias modificações ambientais relacionadas ao desmatamento destacam-se a erosão e os desequilíbrios nos estoques e na natureza das fontes de carbono. Resultados das análises de carbono total (Ctotal) e carbono isotópico de quatro categorias de uso – remanescente de cerrado arbóreo, rotação de soja e milho em sistema de plantio direto, pastagem manejada e pastagem degradada – revelaram que a conversão de uso e manejo provocaram mudanças importantes na natureza e no teordo carbono do solo. Os resultados apresentados podem podem servir como importantes indicadores de impactos ambientais quando ecossistemas naturais são convertidos em sistemas agropecuários sem adoção de manejo adequado.

The Brazilian savannah (cerrado) is an area of expansion of agribusiness. Among the various environmental changes related to deforestation of the savannah stand out impacts related to soil organic matter such as the imbalances in stocks and the changing nature of soil organic carbon. The objective of these study was to evaluate changes in nature (δ13C) and quantity (C%) of soil carbon after conversion of the dense savannah vegetation in areas under different lan duses (pasture, soybeans, corn / soybean rotation), management (conventional and zero tillage) developed in soils with different textural characteristics. The results showed that the average data set of non–managed grazing was the most distanced from the value obtained in cerrado soil. Another factor that determined the lowest concentrations of organic carbon was the presence of sandy soil. The results showed that the carbon C4 grasses in areas occupied by pastures, with or without management, replaced the original C3 carbon originated by cerrado. In the areas of conventional tillage, and no–tillage soybean, and consortium soybean/corn, no clear trend of impoverishment or enrichment of carbon and the carbon substitution as well as the incorporation of different nature of the carbon could be found.

O intemperismo e a perda geoquímica dos elementos que compõem as rochas e solos são mecanismos importantes de evolução das paisagens tropicais. Na região sudoeste da Amazônia brasileira, a presença de depressões topográficas nas superfícies dos platôs suavizados e rebaixados determina a associação de solo Cambissolo, relativamente bem drenado, de constituição laterítica e presente nas partes topograficamente elevadas dos platôs, com solo Gleissolo mal drenado, sazonalmente saturado, desferruginizado e rico em matéria orgânica, presente nas depressões topográficas. Nesta unidade de paisagem, o estudo de uma topossequência representativa do sistema pedológico mostrou que o Cambissolo evolui verticalmente por pedoplasmação a partir de horizontes plínticos e o Gleissolo evolui lateralmente, transformando as características originais do Cambissolo, devido ao caráter semi-aberto da depressão e ao fluxo hídrico subsuperficial lateral que esvazia, nos meses de baixa precipitação, a depressão saturada de água. Determinações dos teores dos óxidos totais por espectrometria de raios-X e da natureza dos argilominerais por difratometria de raios-X evidenciaram evolução lateral remontante do Gleissolo a partir do centro da depressão. Condições redutoras e conexão da depressão com o eixo de drenagem resultaram em acentuada perda de argila e aumento relativo da fração arenosa e da macroporosidade na matriz do solo, acompanhado por decréscimo dos teores de Fe2O3, Al2O3 e outros elementos químicos. O empobrecimento químico e de argilas resultam em mudanças mineralógicas com presença marcante de caulinita, vermiculita-Al e gibbsita, acompanhada por diminuição da illita. A relação pedogênese-morfogênese é determinada pelo regime hídrico, que acentua a erosão geoquímica, o aprofundamento e alargamento das depressões e o consequente aumento da dissecação e lento rebaixamento da superfície topográfica.

The concentration and mobility of metals in the lithosphere and hydrosphere are led by many physical-chemical parameters and processes from natural and anthropogenic origins, the last one resulting in impacts over many ecosystems around the World, including wetlands. These transitional zones, often characterized by the presence of hydric soils, adapted vegetation, and seasonal or permanent presence of surface water, are commonly under human pressure in terms of land use conversion and contamination, notably in agricultural production areas, where excess of nutrients/organic matter, pesticides, salts, sediments, heavy metals and radionuclides (originated from inorganic fertilizers) can substantially alter the ecological balance of those ecosystems. Thus, this study aimed to evaluate the agricultural impact over a tropical geographically isolated wetland in the Brazilian Cerrado by the analysis of geochemical mobility and interaction between surface and groundwater through in situ gamma-ray spectrometry and hydraulic conductivity measurements. The results demonstrated that the margins of this diabase-derived soil wetland are one of the most important and critical compartments due to its capacity of metal immobilization and surface water infiltration, indicated especially by uranium concentrations. Thorium, in turn, was most related to colluvial transport from slopes to the center of wetland. It was also corroborated by low hydraulic conductivity zones as a result of soil compaction due to heavy agricultural machinery and increase in runoff fluxes. Thus, this methodology could be used as an initial fast screening method in wetlands under other climatic and geological/pedological contexts to evaluate the local hydrogeochemical dynamics and impacts of agricultura.

In two small and isolated wetlands located at the interface of the Atlantic Forest and Brazilian savanna (Cerrado) in São Paulo State, Brazil, we employed a pixel-based supervised classification approach using a combination of panchromatic and multispectral bands obtained from Landsat 2, 5, 7, and CBERS-04A satellites (ranging from 80 to 2 m/pixel). In addition, we acquired DJI Phantom 4 Pro UAV-RGB images in twelve different periods with a resolution of +5 cm/pixel. Furthermore, we utilized 2D and 3D Electrical Resistivity Tomography (ERT) to obtain data on the surroundings and center of the wetlands. Finally, we conducted a climatological data analysis. The results from the multisource data allowed us to classify the ecosystems as geographically isolated wetlands (GIWs), for which we documented a seasonal month-to-month (12 months) spatial variation of inundated area, vegetation pattern, soil water interaction, and a point of surface and deep-subsurface water interaction. These results are essential for high-accuracy characterization of small wetlands’ hydrodynamics and hydroperiods at the local scale. Our study contributes to optimizing GIWs understanding, monitoring, and reapplication of the methodology in other wetlands or small ecosystems.

The main biofuel produced in Brazil is ethanol representing 16% of energy production in the national energy matrix, that is why sugarcane is one of the most important crops for Brazilian agriculture. The land conversion associated with the advancement of agriculture is often carried out inappropriately advancing over areas of high environmental sensitivity, such as natural small wetlands. The level of detail required to monitor subtle changes in their dynamics and landscape makes very high-resolution images (+ 10 cm/pixel resolution) acquired by unmanned aerial vehicles (UAVs) an excellent data. The objective of this research was to use UAV orthomosaics and digital elevation models to carry out seasonal monitoring, simulate the water flow in the areas of hydric-contribution and inland flooding, and validate the flooding simulations. The studied wetland located in the State of São Paulo (Paulista Peripheral Depression), showed a seasonal surface water storage capacity (28,067 m³) and a loss of approximately 12.27% of its total area between October 2019 and February 2020. The flooding simulations were validated with data observed by the imagery (variation of ± 3.27%.), being possible to be reapplied in several small ecosystems.

A área de estudo corresponde ao covoal do Córrego da Fortaleza, afluente do rio Uberabinha localizado na chapada Uberlândia-Uberaba. O covoal é um microrrelevo encontrado ao longo da chapada, principalmente nas cabeceiras de drenagens, formando pequenas depressões no solo com impedimento à drenagem. Eles são compostos por morrotes presentes em maior quantidade nas bordas do covoal, tornando menos expressivos no centro, onde a presença de água é maior. O objetivo deste trabalho foi avaliar as diferenças em uma catena na cabeceira do ribeirão Fortaleza que associa Latossolo e Gleissolo a fim de determinar propriedades que podem ser usadas como elementos para a reflexão sobre a relação solo-paisagem. Para isso, fizemos análises de granulometria, porosidade total, macroporosidade, microporosidade e densidade do solo juntamente com análise da cor do solo pelo código Munsell. Foram constatadas mudanças nas propriedades físicas e químicas dos solos, com diminuição da argila da Borda para o Centro do Covoal e aumento da areia nesta mesma direção. A transição de um pedoambiente aerado para outro com baixa circulação hídrica faz com que ocorram diversas reações químicas no solo que podem ser inferidas a partir de sua cor. Com presença de solo amarelo na Borda e um solo Cinza no Centro do covoal. A análise da dinâmica destes ambientes se faz necessária para compreender sua importância ecológica e consequentemente sua imprescindível preservação.

Os sistemas úmidos - veredas e murundus - nas superfícies das chapadas do oeste mineiro correspondem a depressões topográficas com afloramento de lençol freático e funcionam como nascentes de rios. São feições geomorfológicas de reconhecida importância para a conservação da flora e fauna endêmicas, dos solos com elevados teores de carbono orgânico e manutenção da quantidade e qualidade dos recursos hídricos. Na área desta pesquisa, por estarem localizados em região de expansão da fronteira agrícola, o cultivo intensivo praticado desde 1970, ultrapassou os limites de ocorrência dos solos lateríticos e ocupou as zonas de transição com os sistemas úmidos que deveriam compor as Áreas de Preservação Permanente (APP), com o objetivo primordial de proteger estas áreas com alta vulnerabilidade à degradação. Somando-se a este processo, o histórico de mudanças do Código Florestal Brasileiro com suas modificações e indefinições em relação a estes sistemas, dificultam o ordenamento de uso da terra e a conservação.