Abstract This study belongs to one part of FATES research program, which studies the fate of terrestrial substances in Kaoping river-sea system. The task is to study the components and properties of sediments and spatial distribution of sedimentation rates off the southwest Taiwan by analyzing water content, TOC, CaCO3, grain size, P-wave velocity and radionuclides 210Pb and 137Cs in sediments. Thirty cores collected for this study were divided into three groups based on topography and they are Kaoping continental shelf, slope and canyon. The highest TOC content is 1.53 % in ORI732-ST31 and TOC content ranges from 0.20~0.93 % for the rest of sediments from other stations. The highest CaCO3 content is found in ORI732-ST18, 30, ORI779-ST1, and ST12. Most of the CaCO3 content is greater than 4% at these four stations. Probably because of the lower sedimentation rates that result in less terrestrial substances for diluting the CaCO3. In the shelf and slope regions, the distribution of grain size progressively decreases as the water depth increases. Grain size in the stations farther down the canyon, however, is coarser than those at upper canyon. It suggests that there is other sediment source for stations in the canyon in addition to the Kaoping river. The sedimentation rates derived from 210Pbex profiles range from 0.073~0.168 cm/yr in shelf, 0.033~0.670 and 0.094~0.411 cm/yr in continental slope and canyon, respectively. Sedimentation rates are all less than 0.2 cm/yr in the shelf area, but there are five stations with sedimentation rates higher than 0.2 cm/yr in the slope and canyon areas. Among the five stations, the sedimentation rate is up to 0.670 cm/yr (ORI779-ST9), suggesting that 302~822 m deep in the slope and 975~1156 m deep in the canyon are the deposition centers. In some stations, anomalously low 210Pbex activities exist in surface or sub-surface sediments, indicating that the low 210Pbex activity sediments may be typhoon-induced turbidite sediments. According to Central Weather Bureau¡¦s typhoon catalog, in the year of coring there were seven typhoons striking Taiwan. Among these typhoons, Hai-tang was the strongest one, suggesting that the turbidite sediments mentioned above were likely caused by typhoon Hai-tang. Besides, turbidite sediments appear at water depth of over 700 m, indicating episodic turbidite events are an important way to transport particles offshore.

For certain shellfish species, a mechanical harvester has the potential to greatly reduce harvesting costs. Traditionally, hand rakes are used in shellfish harvesting in British Columbia. In order to determine if it is environmentally feasible to use a mechanical harvester, an environmental assessment on mechanical harvesting and traditional harvesting needs to occur for comparison. In July 2008, a preliminary oceanographic assessment was conducted at three study sites in Baynes Sound. Each of the three study sites contained a mechanical and manual harvest plot and reference stations. Sampling stations were established at fixed positions within each plot and at four positions along a downstream transect (following the dominant current direction.) Surveys were conducted 24 hours pre-harvest, immediately post-harvest, and 24 hours post-harvest. Parameters included in situ sediment sulphides, eH (REDOX), sediment grain size (SGS), visual condition (digital imagery), sedimentation (silt flux) and sediment macro-fauna. Results show only localized environmental effects associated with each harvest approach; with no significant difference documented between the manual and mechanical harvesting methods on the study beaches. These results indicate the use of a mechanical shellfish harvester is as environmentally sound as the traditional method of hand harvesting, and poses no additional environmental risks. Introducing mechanization in shellfish harvesting will allow shellfish producers to reduce costs and increase profits, making the British Columbian shellfish industry more competitive with other suppliers. / Graduate

Sedimentation rates in sediment cores from Lavaca Bay have been high within the last 1-2 decays within the central portion of the bay, with small fluctuations from river input. Lavaca Bay is a broad, flat, and shallow (<3 m) microtidal estuary within the upper Matagorda Bay system. Marine derived sediment enters the system from Matagorda Bay, while two major rivers (Lavaca & Navidad) supply the majority of terrestrially derived sediment. With continuous sediment supply the bay showed no bathymetric change until the introduction of the shipping channel. Processes that potentially lead to sediment transport and resuspension within the bay include wind driven wave resuspension, storm surges, wind driven blowouts, and river flooding. These processes were assessed using X-radiographs, grain size profiles, and 210Pb and 137Cs geochronology of sediment diver cores. In six cores the upper 10 cm of the seabed has been physically mixed, where as the rest showed a continuous sediment accumulation rate between 0.84-1.22 cm/yr. Sidescan sonar and subbottom chirp sonar data coupled with sedimentological core and grab samples were used to map the location and delineate the sedimentary facies within the estuarine system in depths >1 m. Five sedimentary facies were identified in Lavaca Bay and adjacent bays, they are: 1) estuarine mud; 2) fluvial sand; 3) beach sand; 4) bay mouth sand; and 5) oyster biofacies. Of the five facies, Lavaca Bay consists primarily of estuarine mud (68%). Pre-Hurricane and post-Hurricane Claudette cores were obtained to observe the impact to the sedimentary processes. The north and south Lavaca Bay were eroded by 10 cm and 2-3 cm, respectively. Cox Bay and Keller Bay saw a net deposition of 2-3 cm.

Thesis advisor: Noah Snyder / The purpose of this study is to quantify land use change in two coastal New England watersheds using lake core analysis, orthorectified historic aerial imagery, and data from the National Land Cover Database (NCLD). The study covers Sennebec and Medomak ponds in coastal Maine, which lie between the Penobscot Bay and the southern stretch of the Kennebec River. With lake cores recording >800 years (Sennebec) and >1600 years (Medomak), the timeframe of this study spans from the era of Indigenous populations, through the period of EuroAmerican settlement, and into the modern day, to provide insight into the interactions between humans and watershed dynamics through time. / Thesis (BS) — Boston College, 2021. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: Departmental Honors. / Discipline: Earth and Environmental Sciences.

Fens are abundant in the San Juan Mountains. By exploring the geomorphology and geochemistry of fen wetlands, the functions that fens serve can be better understood. In this research, two main studies were conducted involving the geomorphology and geochemistry of fens. The first study involved a complex investigation of the geomorphology of five fen sites in the San Juan Mountains near Silverton, Colorado. Geomorphic maps were constructed for each fen site at a scale of ~1:3,000. A geomorphic classification scheme was then made based on fen location, and fens were placed in one of three categories: 1) valley-bottom, 2) valley-side, and 3) terrace. Fen circularity and elongation values were calculated for thirty fens to determine morphometry. A pattern for elongation of fens emerged between the three types of alpine fens with valley-bottom fens having an average elongation value of 1.7, valley-side 2.4, and terrace 1.9. Valley-side fens are more elongated than valley-bottom and terrace fens, which exhibit similar elongation values. In addition, sediment samples at each site were sectioned along visual breaks in the sediment column and were sieved. Mean phi values were calculated for each section and at each site. The mean phi values at California Gulch, Glacial Lake Ironton, Howardsville, Red Mountain Pass North, and Red Mountain Pass South, are 0.2112, 0.9045, 1.6028, 0.0178, and 1.0516, respectively. Overall, coarse-grained particles are associated with valley-side fens, and medium-grained particles are associated with valley-bottom and terrace fens. The second part of the study involved investigating the geochemistry of fen sediment. The geochemistry portion of this research focused on concentration and isotopic ratios of Pb and the amount of 137Cs in fen sediment to better understand variations of Pb with depth and calculate approximate sedimentation rates. Based on isotopic ratios of Pb, binary mixing was determined with the presence of ore mineralized Pb and non-ore mineralized. Binary mixing of two types of ore-mineralized Pb is present at the Howardsville fen and both ore-mineralized and non-ore mineralized Pb is present at the Red Mountain Pass North fen. Based on 137Cs in fen sediment at Howardsville, an average rate of deposition of sediment is approximately 0.16 cm/yr, with a visible change in sedimentation rates pre- and post-1960s.

Galveston Bay is the second largest estuary in the Gulf of Mexico. The bay’s watershed and shoreline contains one of the largest concentrations of petroleum and chemical industries in the world, with the greatest concentration within the lower 15 km of the San Jacinto River/Houston Ship Channel (SJR/HSC). Extensive groundwater has been withdrawn to support these industries and an expanding population has resulted elevated land subsidence, with the highest land subsidence in the lower SJR/HSC, of over 3 m (3 cm yr^-1) and has decreased seaward throughout the bay to 0.6 cm yr^-1 near Galveston Island. Mercury (Hg) contamination is well documented throughout the bay’s sediments. Sediment vibra-cores were collected throughout the bay systems. 210Pb and 137Cs geochronologies from these cores was used to determine sedimentation rates and correlated to Hg profiles to estimate input histories. Relative Sea Level Rise (RSLR) is the sum of eustatic sea level rise and land subsidence. The results show sedimentation rates are high in areas with high rates of RSLR and the rates are of the same order of magnitude, however, in general, sedimentation rates are as much as 50% of RSLR, indicating that sedimentation has not kept pace with land subsidence, although they have the same relative order. Hg core profiles were correlated with radioisotope geochronologies and show significant input of Hg beginning around 1940, with a peak around 1971, and a dramatic drop off in concentration afterwards, demonstrating it to be a valuable geochronology tool. Hg concentrations were found to be dramatically higher proximal to the SJR/HSC and progressively decreasing seaward and to distal parts of the bay.

A qualidade ambiental de um corpo d\'água é resultado da situação de sua bacia de drenagem, de modo que as transformações que ocorrem no solo do entorno provocam mudanças significativas no ambiente aquático. Por isto, cada vez mais se trabalha com conceito de manejo integrado dos ambientes. Desta forma, o conhecimento dos processos de geração, transporte e deposição de sedimentos, por serem fontes de sólidos, nutrientes e contaminantes ao corpo d\'água, é de vital importância para a conservação, desenvolvimento e manejo integrado dos recursos hídricos. Neste sentido, essa dissertação apresenta um estudo a respeito da exportação e deposição de sólidos e nutrientes na sub-bacia do Ribeirão das Cruzes, no município de Santo Antônio do Aracanguá, SP, na Unidade de Gerenciamento de Recursos Hídricos do Baixo Tietê (UGRHI - 19). Esse corpo d\'água foi subdividido em compartimentos e analisado por transectos, ou seja, eixos transversais ao fluxo, sendo que experimentos envolvendo instalação de câmaras de sedimentação, coleta de sedimentos de fundo e medições de vazão foram conduzidos em dois períodos hidrológicos distintos: um em janeiro, durante a estação chuvosa, e outro em agosto, durante a estação seca. A taxa máxima de deposição de sólidos suspensos foi de 62,40 g/m² dia durante a Estação Chuvosa, e de 37,29 g/m² dia, durante a Estação seca. Ainda, a taxa média de deposição de nitrogênio total Kjeldahl foi de 0,53 e 2,02 g/m² dia e a de fósforo total foi de 139,67 e 103,89 mg/m² dia, durante as Estações Chuvosa e Seca, respectivamente. Quanto às taxas de exportação, para sólidos suspensos foram observadas médias de 2328,44 e 725,96 ton/dia, de nitrogênio total Kjeldahl foram de 121,41 e 299,84 ton/dia e para fósforo total foram de 14,86 e 10,05 ton/dia, durante as Estações Chuvosa e Seca, respectivamente. Os resultados obtidos, comparados a outros estudos em ambientes similares, revelam altas taxas de deposição e exportação de sólidos e nutrientes, demonstrando, desta forma, a incidência dos processos de eutrofização e assoreamento do recurso hídrico, bem como a expressão dos impactos provenientes do uso e ocupação do solo do entorno, capaz de influenciar na qualidade da água do ambiente. / The environmental quality of waterbody is the result of the situation of its drainage basin, so that the transformations that occur on the soils surrounding cause significant changes in the aquatic environment. Therefore, each time more has been increasing the works with the concept of integrated management of environments. Thus, the knowledge about the processes of generation, transport and deposition of sediments, because they are sources of solids, nutrients and contaminants to waterbody, is extremely important for the conservation, development and integrated management of water resources. In this way, this dissertation presents a study concerning the deposition and export of solids and nutrients in the Ribeirão das Cruzes sub-basin, in Santo Antônio do Aracanguá city, SP, in Baixo Tietê Water Resources Management Unit (WRMU - 19). This waterbody was divided into compartments and analyzed by transects, which are transverse axes to the flow, and experiments involving installation of sedimentation traps, collect of bottom sediments and flow measurements were carried out in two distinct hydrological periods: one in January during the rainy season, and another in August, during the dry season. The maximum suspended solids deposition rate were 62.40 g/m² day during the rainy season, and 37.29 g/m² day during the dry season. So, the average rate of nitrogen deposition were 0.53 and 2.02 g/m² day, and the rate of phosphorus were 139.67 and 103.89 mg/m² day, during the rainy and dry seasons, respectively. As for exportation rates, the average rates found of suspended solids were 725.96 and 2328.44 ton/day, the rates of nitrogen were 121.41 and 299.84 ton/day, the rates of phosphorus were 14.86 and 10.05 ton/day, during the rainy and dry seasons, respectively. The results obtained, when compared to other studies in similar environments, show high rates of solids and nutrients deposition and export, demonstrating, this way, the incidence of eutrophication processes and siltation of the water resources, as well as the expression of impacts from the landuse, able to influence the water quality.

Submitted by Socorro Pontes (socorrop@ufersa.edu.br) on 2017-05-15T15:14:37Z No. of bitstreams: 1 JulioCSC_DISSERT.pdf: 1676020 bytes, checksum: e30206673c4aba0ea83d2d80b17e045b (MD5) / Made available in DSpace on 2017-05-15T15:14:37Z (GMT). No. of bitstreams: 1 JulioCSC_DISSERT.pdf: 1676020 bytes, checksum: e30206673c4aba0ea83d2d80b17e045b (MD5) Previous issue date: 2017-03-17 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Concerns regarding the sustainability of aquaculture enterprises as well as the modifications that they can provide to aquatic environments are fundamental in water bodies, mainly in semi-arid reservoirs, where occurs a constant water scarcity. Thus, this work aimed to evaluate the sedimentation of nutrients and particulate matter, as well as the environmental, social and economic sustainability of a tilapia breeding system in net cages in a Brazilian semi-arid reservoir. The study was conducted in a cooperative of entrepreneurs who manage a Nile tilapia production in net cages in the reservoir Umari (5°42’13”S and 37°15’18”O). The sediment generated by the net cages was analyzed, as well as were used 40 sustainability indicators, being the system sustainability modeled through the theoretical Drivers-Pressure-State-Impact-Response framework, in which two scenarios were considered. real breedings, which operated with stocking densities of 100 and 125 fish/cage, with four cycles of annual breeding (DENS 100 CC; DENS 125 CC, respectively) and two hypothetical scenarios considering a density of 100 and 125 fish/cage, with two annual breeding cycles (DENS 100 CL, DENS 125 CL, respectively). The sedimentation rates in the net cages were significantly higher when compared to the observed rates in the reservoir region without the influence of the net cages, demonstrating that the fish farming activity in net cages raises the sedimentation rates of nutrients and particulate matter in this reservoir, what may contribute to accelerate the eutrophication process of this aquatic environment. However, the results showed that the sedimentation rates increase was punctual, that is, still is restricted to the fish farming in net cages region in the Umari reservoir. From the comparison between the scenarios provided by the modeling, it was evident that the real breedings despite have presented better performance in environmental and social sustainabilities were not viable from the economic point of view, which may cause the end of the enterprise and consequently the reduction of social benefits for the local population. The modeling also demonstrated that alterations in the increase of the breeding time and the consequent decrease of the annual production cycles, increased the sustainability in a global way, but at the same time reduced the environmental sustainability, being important to highlight that as a result of the semiarid region presents peculiar characteristics with relation to the water scarcity, the low environmental sustainability of the intensive fish farming activities in net cages carried out in these reservoirs may in the medium term economically and socially compromise the activity / Preocupações com relação à sustentabilidade dos empreendimentos aquícolas bem como as modificações que eles podem proporcionar aos ambientes aquáticos são fundamentais em corpos hídricos, principalmente em reservatórios do semiárido, onde ocorre uma constante escassez de água. Assim, o objetivo deste trabalho foi avaliar a sustentabilidade ambiental, social e econômica de um sistema de cultivo de tilápias em tanques-rede em um reservatório do semiárido brasileiro. O estudo foi realizado em um sistema produção de tilápias do Nilo em tanques-rede no reservatório de Umari (5°42’13”S e 37°15’18”O), administrado por uma cooperativa de empresários. Foram realizadas análises do sedimento gerado pelos tanques-rede, bem como foram utilizados 40 indicadores de sustentabilidade, sendo que e a sustentabilidade do sistema foi modelada através do arcabouço teórico Drivers-Pressure-State-Impact-Response. Foram considerados dois cenários com cultivos reais, que operavam com as densidades de estocagem com 100 e 125 peixes/m² e quatro ciclos de cultivo anual (DENS 100 CC; DENS 125 CC, respectivamente), e dois cenários hipotéticos considerando uma densidade de 100 e 125 peixes/m², com dois ciclos de cultivo anual (DENS 100 CL; DENS 125 CL, respectivamente). As taxas de sedimentação abaixo dos tanques-rede foram significativamente superiores quando comparadas com as taxas observadas na região do reservatório sem influência da piscicultura, demonstrando que esta atividade eleva as taxas de sedimentação de nutrientes e material particulado neste reservatório, podendo contribuir para acelerar o processo de eutrofização deste ambiente aquático. Os resultados mostraram que o aumento das taxas de sedimentação foi pontual, ou seja, ainda é restrita a região de criação de O. niloticus em tanques-rede no reservatório. O estudo evidenciou que os cultivos reais apesar de terem apresentado melhores desempenhos nas sustentabilidades ambiental e social, quando comparados com os cenários hipotéticos, foram inviáveis do ponto de vista econômico, podendo causar o fim do empreendimento e consequentemente a redução dos benefícios sociais para a população local. A modelagem demonstrou ainda que alterações no aumento do tempo de cultivo e a consequente diminuição da quantidade de ciclos anuais de produção aumentou a sustentabilidade de forma global, mas ao mesmo tempo reduziu a sustentabilidade ambiental. É importante destacar que em decorrência da região semiárida brasileira apresentar características peculiares com relação à escassez de água, a baixa sustentabilidade ambiental das atividades de piscicultura intensiva em tanques-rede realizadas em reservatórios desta região podem em médio prazo comprometer economicamente e socialmente a atividade / 2017-05-15

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No. of bitstreams: 1 AmbrosioPBJ_TESE.pdf: 1565908 bytes, checksum: 8e51f42daddfb44d1d69d9f37babeec1 (MD5) Previous issue date: 2017-11-27 / Aquaculture studies seem to be basically based on environmental and economic terms in isolation, not considering the interaction of these factors, and rarely taking into account the social costs and benefits involved in the activity, so the objective of this research was to evaluate sustainability economic, environmental and social aspects in the creation of Litopenaeus vannamei shrimp in different management strategies and storage densities. For this purpose, densities of 92 (M1), 14 (M2) and 8 (M3) shrimp.m-2 and with maximum culture time of 79 days. The sedimentation rates, with the exception of total inorganic carbon-TIC and total organic carbon-TOC, were significantly higher in M3 when compared to M1 and M2, in the first collection period, probably influenced by management in the first stage (greenhouse), a tendency of decrease was verified for most of nutrient sedimentation rates for the end of the cycle, and may be associated with the bacterial community that may have aided in the reduction of these compounds. Survival was reduced in all treatments, probably influenced by white spot disease and high water salinity of farms raising the apparent feed conversion factor-FCAA in M1 and M2. The internal rates of return for M2 and M3 were attractive, generating a positive net profit and a positive balance and were able to guarantee the return on invested capital. However, this return on capital only occurred due to the high prices practiced in 2016. The cultivation with high initial population (M1) caused economic and zootechnical losses due to the high FCAAs, reduced individual biomass and the high total operational costs - making this treatment unfeasible. In the social evaluation, an income distribution of the negative order for M1 was verified due to the high costs of production, thus creating losses for this treatment. M2 and M3 presented a reduced income distribution, with a labor compensation of R $ 0.70 and R $ 1.06, respectively, representing 48 and 32% of production costs (COT). The greater distance from the economic dimension to the M1 treatment may be associated with the high RB and COT results. The treatments M2 and M3 were those that presented positive IRR, demonstrating the economic viability, probably due to the high prices per kilo of shrimp practiced during this period. Sustainability was committed by the generation of solid waste, since much of the particulate matter produced in shrimp farms is formed by a collective action of chemicals, fertilizers, excrement, undigested food, unwanted organisms and debris. It is worth noting that the white spot negatively affected the economic and social sustainability of all treatments. M1 was the most favorable environmental treatment with a social tendency. We can conclude that the monoculture of shrimp when carried out with high initial populations can not guarantee the return of invested capital. M2 and M3 were only economically viable due to the high prices paid per kilo of shrimp, but with low employment and income generation, not being socially fair and with greater impact on the environment / Os estudos em aquicultura parecem se pautar basicamente em termos ambientais e econômicos de forma isolada, não considerando a interação destes fatores, e raramente levando em considerações os custos e benefícios sociais envolvidos na atividade, desta forma o objetivo desta pesquisa foi avaliar a sustentabilidade econômica, ambiental e social na criação do camarão marinho Litopenaeus vannamei em diferentes estratégias de manejo e densidades de estocagem. Para tanto foram utilizadas densidades de 92 (M1), 14 (M2) e 8 (M3) cam.m-2 e com tempo máximo de cultivo de 79 dias. As taxas de sedimentação, com exceção do carbono inorgânico total-CIT e carbono orgânico total-COT, foram significativamente superiores em M3 quando comparado a M1 e M2 no primeiro período de coleta, provavelmente influenciadas pelo manejo na primeira fase (estufa). Foi verificado uma tendência de decréscimo para a maioria das taxas de sedimentação de nutrientes para o final do ciclo, podendo estar associada a comunidade bacteriana que pode ter auxiliado na redução desses compostos. As sobrevivências foram reduzidas em todos os tratamentos, provavelmente influenciadas pela doença da mancha branca e a elevada salinidade da água dos viveiros de criação elevando o FCAA em M1 e M2. As taxas internas de retorno para M2 e M3 foram atrativas, gerando lucro e saldo positivo para o valor presente líquido e conseguiram garantir o retorno do capital investido. Esse retorno do capital, no entanto, somente ocorreu devido aos preços elevados praticados em 2016. O cultivo com população inicial elevada (M1), ocasionou prejuízos econômicos e zootécnicos devido aos elevados FCAAs, biomassa individual reduzida e aos elevados custos totais operacionais-CTO, tornando inviável esse tratamento. Na avaliação social foi verificada uma distribuição de renda da ordem negativa para M1 em função dos elevados custos de produção, configurando prejuízos para esse tratamento. M2 e M3 apresentaram distribuição de renda reduzida, sendo a remuneração da mão de obra de R$ 0,70 e R$ 1,06 respectivamente, representando 48 e 32% dos custos de produção (CTO). O maior distanciamento da dimensão econômica para o tratamento M1 pode estar associado aos resultados elevados com RB e CTO. Os tratamentos M2 e M3 foram os que apresentaram TIR positiva, demonstrando a viabilidade econômica, provavelmente em função dos preços elevados por quilo de camarão praticados nesse período. A sustentabilidade foi comprometida pela geração de resíduos sólidos, visto que grande parte do material particulado produzido em viveiros de camarão é formada por uma ação coletiva de produtos químicos, fertilizantes, excrementos, alimentos não digeridos, organismos indesejados e detritos. Vale salientar ainda que, a mancha branca comprometeu negativamente a sustentabilidade econômica e social de todos os tratamentos. M1 foi o tratamento mais favorável ambiental com tendência para o social. Podemos concluir que o monocultivo de camarão quando realizado com elevadas populações inicias não consegue garantir o retorno do capital investido. M2 e M3 só foram viáveis economicamente em função dos preços elevados pagos por quilo de camarão, porém com reduzida geração de emprego e renda, não sendo socialmente justo e com maior impacto ao meio ambiente / 2017-12-22

A qualidade ambiental de um corpo d\'água é resultado da situação de sua bacia de drenagem, de modo que as transformações que ocorrem no solo do entorno provocam mudanças significativas no ambiente aquático. Por isto, cada vez mais se trabalha com conceito de manejo integrado dos ambientes. Desta forma, o conhecimento dos processos de geração, transporte e deposição de sedimentos, por serem fontes de sólidos, nutrientes e contaminantes ao corpo d\'água, é de vital importância para a conservação, desenvolvimento e manejo integrado dos recursos hídricos. Neste sentido, essa dissertação apresenta um estudo a respeito da exportação e deposição de sólidos e nutrientes na sub-bacia do Ribeirão das Cruzes, no município de Santo Antônio do Aracanguá, SP, na Unidade de Gerenciamento de Recursos Hídricos do Baixo Tietê (UGRHI - 19). Esse corpo d\'água foi subdividido em compartimentos e analisado por transectos, ou seja, eixos transversais ao fluxo, sendo que experimentos envolvendo instalação de câmaras de sedimentação, coleta de sedimentos de fundo e medições de vazão foram conduzidos em dois períodos hidrológicos distintos: um em janeiro, durante a estação chuvosa, e outro em agosto, durante a estação seca. A taxa máxima de deposição de sólidos suspensos foi de 62,40 g/m² dia durante a Estação Chuvosa, e de 37,29 g/m² dia, durante a Estação seca. Ainda, a taxa média de deposição de nitrogênio total Kjeldahl foi de 0,53 e 2,02 g/m² dia e a de fósforo total foi de 139,67 e 103,89 mg/m² dia, durante as Estações Chuvosa e Seca, respectivamente. Quanto às taxas de exportação, para sólidos suspensos foram observadas médias de 2328,44 e 725,96 ton/dia, de nitrogênio total Kjeldahl foram de 121,41 e 299,84 ton/dia e para fósforo total foram de 14,86 e 10,05 ton/dia, durante as Estações Chuvosa e Seca, respectivamente. Os resultados obtidos, comparados a outros estudos em ambientes similares, revelam altas taxas de deposição e exportação de sólidos e nutrientes, demonstrando, desta forma, a incidência dos processos de eutrofização e assoreamento do recurso hídrico, bem como a expressão dos impactos provenientes do uso e ocupação do solo do entorno, capaz de influenciar na qualidade da água do ambiente. / The environmental quality of waterbody is the result of the situation of its drainage basin, so that the transformations that occur on the soils surrounding cause significant changes in the aquatic environment. Therefore, each time more has been increasing the works with the concept of integrated management of environments. Thus, the knowledge about the processes of generation, transport and deposition of sediments, because they are sources of solids, nutrients and contaminants to waterbody, is extremely important for the conservation, development and integrated management of water resources. In this way, this dissertation presents a study concerning the deposition and export of solids and nutrients in the Ribeirão das Cruzes sub-basin, in Santo Antônio do Aracanguá city, SP, in Baixo Tietê Water Resources Management Unit (WRMU - 19). This waterbody was divided into compartments and analyzed by transects, which are transverse axes to the flow, and experiments involving installation of sedimentation traps, collect of bottom sediments and flow measurements were carried out in two distinct hydrological periods: one in January during the rainy season, and another in August, during the dry season. The maximum suspended solids deposition rate were 62.40 g/m² day during the rainy season, and 37.29 g/m² day during the dry season. So, the average rate of nitrogen deposition were 0.53 and 2.02 g/m² day, and the rate of phosphorus were 139.67 and 103.89 mg/m² day, during the rainy and dry seasons, respectively. As for exportation rates, the average rates found of suspended solids were 725.96 and 2328.44 ton/day, the rates of nitrogen were 121.41 and 299.84 ton/day, the rates of phosphorus were 14.86 and 10.05 ton/day, during the rainy and dry seasons, respectively. The results obtained, when compared to other studies in similar environments, show high rates of solids and nutrients deposition and export, demonstrating, this way, the incidence of eutrophication processes and siltation of the water resources, as well as the expression of impacts from the landuse, able to influence the water quality.