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Watersheds have different water compartments (surface, subsurface,and underground) connected by the soil-water interface. In orderto be able to relate these compartments, monitoring data arenecessary, such as the case of the Ribeirão Concórdia watershed,in Lontras, Santa Catarina (SC). This study aimed to evaluate thebehavior and the correlation between rainfall-runoff and phreaticsurface levels with chemical species concentrations in surface andgroundwaters in a rural watershed. Data of 3 piezometers installedin the hydrographic basin were used: PZ2127, PZ3, and PZMC.The piezometers are equipped with hydrostatic level sensors. Afluviometric station is located adjacent to PZ2127 (near the catchmentoutlet). Concentrations of anions and carbon forms were analyzedin water samples (river and piezometers) taken every 2-3 weeks,from January 14, 2012, to December 23, 2016, totaling 103 samples.Correlations between daily data were verified using Pearson’scorrelation coefficient (ρ). The river presented a dilution effect, whilethe adjacent piezometer had the highest average concentrations ofchemical species. Precipitation and chemical species concentrationshowed no seasonal pattern, with events/peaks throughout the year.Higher concentrations of carbon forms were found in the summer,while lower concentrations were observed in the winter. Positivecorrelations between concentrations of anions and carbon forms insurface and groundwaters were obtained. Bacias hidrográficas apresentam diferentes compartimentos de água(superficial, subsuperficial e subterrâneo) que estão ligados pela interfacesolo-água. Para conseguir relacionar esses compartimentos são necessáriosdados de monitoramento, como é o caso da bacia hidrográfica do RibeirãoConcórdia, em Lontras (SC). Este estudo avaliou o comportamentoe a correlação entre o escoamento fluvial e a elevação da superfíciefreática, com concentrações de espécies químicas, em águas superficiaise subterrâneas em uma bacia hidrográfica rural. Utilizaram-se dadosreferentes a três piezômetros instalados na bacia hidrográfica: PZ2127, PZ3e PZMC. Estes são equipados com sensores de nível hidrostático. Adjacenteao PZ2127 (próximo ao exutório), existe uma estação de monitoramentofluviométrico (R). Amostras de concentrações de ânions e formas decarbono foram coletadas no rio e nos piezômetros em uma frequênciade 2–3 semanas, entre 14 de janeiro de 2012 e 23 de dezembro de 2016,totalizando 103 amostras. Correlações de dados diários foram verificadaspor meio do coeficiente de correlação de Pearson (ρ). O rio apresentoumenores concentrações das espécies químicas analisadas, enquanto opiezômetro adjacente apresentou as maiores concentrações médias dessasespécies. Precipitação e concentração das espécies químicas não exibirampadrão sazonal, com ocorrência de eventos/picos ao longo do ano. Formasde carbono apresentaram maiores concentrações nas coletas no verão emenores no inverno. Obteve-se correlação positiva entre as concentraçõesde ânions e das formas de carbono da água do rio e dos piezômetros.

Os estudos hidrossedimentológicos abordam as contribuições da agricultura,do meio urbano e das demais ocupações da terra, entretanto as estradasrurais inseridas nas bacias hidrográficas dificilmente são observadas comocontribuição específica ou potencialmente contributiva. Desse modo, osobjetivos deste estudo foram simular diferentes cenários e características paraas estradas rurais e, assim, avaliar o fluxo de águas e sedimentos em bacias comagricultura familiar localizadas no sul do Brasil. Para isso, utilizou‑se o modelohidrológico soil and water assessment tool (SWAT). Na etapa de calibraçãoda vazão para a bacia do Ribeirão Concórdia, obtiveram‑se o coeficientede Nash-Sutcliffe (COE) de 0,76 e, para a validação, o coeficiente de 0,78.Na bacia do Rio Camboriú, a calibração alcançou COE de 0,67. Na calibraçãoe validação sedimentológica na bacia do Ribeirão Concórdia, obteve-se COEde 0,82 e de 0,68, respectivamente. Na bacia do Rio Camboriú, a calibraçãosedimentológica atingiu coeficiente de 0,59. Quando comparada com ocenário sem as estradas, a inserção de estradas rurais como uso específicoda terra (cenário calibrado) resultou em aumento de 6,3% na vazão e de8,8% nos sedimentos transportados na bacia do Ribeirão Concórdia. Na baciado Rio Camboriú, houve diferenças inferiores a 0,4%. Portanto, mesmoapresentando uma pequena área dentro da bacia, as estradas rurais podeminterferir na vazão e no volume de sedimentos transportados. Hydrosedimentological studies address the contributions of agriculture, urbanenvironment, and other land occupations. However, rural roads within thewatersheds are hardly seen as a specific or potential contribution. Thus, theaim of this study is to simulate different scenarios and characteristics for ruralroads and assess its the flow of water and sediments in family farming basinslocated in the southern brazil. For this, the soil and water assessment tools(swat) hydrological simulation model was applied. In the flow calibrationstage for the Concórdia stream basin, a nash-sutcliffe coefficient (COE) of0.76 was obtained, and for validation, a coefficient of 0.78. While in theCamboriú river basin, the COE reached 0.67. For sedimentological calibrationand validation, the Concórdia creek basin obtained an COE of 0.82 and 0.68,respectively. While in the Camboriú river basin, sedimentological calibrationreached a coefficient of 0.59. When compared to the scenario without theroads, the insertion of rural roads as specific land use resulted in a 6.3%increase in flow rate and 8.8% in sediments transported in the Concórdiacreek basin. For the Camboriú river basin, the differences were below 0.4%.Therefore, even with a small area within the basin, rural roads may interferewith the flow and volume of transported sediment.

Zinc (Zn) is a trace element (TE) that occurs naturally in soils, however spreading Zn-rich organic waste (OW) on farmlands may lead to hazardous Zn levels. Common problems are related to phytotoxicity, introduction into the food chain and groundwater contamination. Assessing the associations between OW-borne Zn and the soil matrix is paramount to predict its short- and long-term behavior in the environment. This is usually pursued by using either single/sequential extractions (SSE) or spectroscopic methods such as XAS. Nevertheless, SSE reflects element extractability rather than the nature of its interactions with bearing phases, while XAS requires synchrotron radiation sources that are not available in certain regions of the world. We applied a third approach in this study – namely soil density fractionation – to isolate and characterize the constituents of the soil matrix (i.e. potential Zn bearing phases) and thereafter identify their associations with natural and OW-borne Zn. The target density fractions were the following: 2.7 g cm-3, plus an extractable fraction. The soil analyzed was a clayey Hapludox soil that received controlled pig slurry applications over 11 years, causing a 2-fold increase in Zn concentration within the surface layer: from 105.8 mg kg-1 of Zn (control soil) to 206.6 mg kg-1 of Zn (amended soil). Among the six selected density fractions, two of them were the most contrasting and representative. (I) The light fraction (