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The studies on hydrosedimentological flows in coastal areas are relevant for the maintenance of ecosystem services, development, land use and water resources. An intense erosive process has caused significant hydrological, sedimentometric and water quality changes in the Lower Araguari River and along a stretch of the coast of Amapá, extreme north of Brazil. The main hypothesis of these changes is channel capture of the Araguari river basin by the Amazon River delta, through natural and artificial channels expanding in both directions, with emphasis on the Igarapé Novo - Gurijuba and Urucurituba Channels. The objective of this research was to evaluate the hydrodynamics, solid discharge (QSS) and water quality of channels that connect these two basins, considering aspects of seasonality and semidiurnal tides. Data were collected in two seasonal periods and six sections (Araguari, Igarapé Novo - Gurijuba and Urucurituba). The quantification methods of the parameters were: a) flow measurement with acoustic Doppler profilers (ADCP); b) water sampling in situ for physicochemical analysis and sediment (suspended solids - SS) and c) solids transport calculation (Qss). The results indicated a remarkable seasonal variability and during tidal cycles for most of the water quality parameters (p

There is little published information on soil characteristics and their relationship with the occurrence of palm trees in the estuarine coast of Amapa. This study was conducted in order to compare the characteristics of the soil and the abundance of palm trees, among the floodplain environments and igapó found in the lower Rio Maraca, near the confluence with the Amazon River. In this portion of the Maraca River basin were allocated 4 transects (T1, T2, T3 and T4) 1000m with 20 plots 10m x 25m each, up the tributary of the Amazon, distant at least 1 km from each other to ensure the independence between them and create a gradient away from the Amazon river. During the summer (December / 2015) were collected with a Dutch auger five single samples of soil at the depth of 0-5 cm to form one sample per share, for the analysis of texture and soil nutrients. The results of the physical and chemical properties of soils were submitted to descriptive statistics, calculating the average, minimum, maximum and coefficient of variation for each attribute in Microsoft Excel 2010. The soil igapó showed higher acidity and exchangeable aluminum content . The Euterpe oleracea Mart species. showed higher density and importance in igapó ecosystem CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior Existem poucas informações publicadas sobre as características dos solos e suas relações com a ocorrência de palmeiras na costa estuarina do Amapá. O presente estudo foi realizado com o objetivo de comparar as características dos solos e a abundância de palmeiras, entre ambientes de várzea e igapó encontrados no baixo rio Maracá, próximo a confluência com o rio Amazonas. Nesta porção da bacia do Rio Maracá foram alocados 4 transectos (T1, T2, T3 e T4) de 1000m com 20 parcelas 10mx25m cada, subindo o afluente do Amazonas, distantes pelo menos 1 km um do outro para garantir a independência entre eles e criar um gradiente de distância do rio Amazonas. No período de verão (dezembro/2015), foram coletadas, com um trado holandês, cinco amostras simples de terra na profundidade de 0-5 cm para compor uma amostra por parcela, para análise de textura e nutrientes do solo. Os resultados dos atributos físicos e químicos dos solos foram submetidos à estatística descritiva, calculando-se a média, valor mínimo, valor máximo e coeficiente de variação para cada atributo no Microsoft Excel 2010. O solo do igapó apresentou maior acidez e teores de alumínio trocável. A espécie Euterpe oleraceae Mart. apresentou maior densidade e importância no ecossistema de igapó