| Resumo: |
This is a study on surficial sediments and bottom water physico-chemical characteristics of the San Jorge Gulf (SW Atlantic, Argentina)during spring 1999 - winter 2000 (first studied period), autumn 2001- summer 2002 (second studied period)and winter 2003 (third studied period), based on samples obtained during research cruises carried out on board of the INIDEP (Instituto Nacional de Investigación y Desarrollo Pesquero)research vessels. Environmental variables such as temperature, salinity, density, oxygen and bottom water chlorophyll a content as well as granulometric fractions, total organic matter, total organic carbon, total nitrogen, total phosphorous, chlorophyll a and phaeopigments in sediment concentration and depth were analyzed. The origen and nutritional value of the deposited organic matter were also assessed. The analyzed variables and distribution patterns and abundance of macrobhentos and shrimp were related. Parametrics and nonparametrics Tests as well as ordenation multivariates techniques were applied for the numeric treatment of the data. To characterize the benthic system of the San Jorge Gulf from a physico-chemical point of view, to know the relationship between physico-chemical characteristics of benthic environment and distribution and concentration of macrobenths, as well as to define relationship between of the environment characteristics and distribution and concentration shrimp, were the main objetives of this study. Spatial distribution of the variables defined three sectors in the San Jorge Gulf, corresponding to the depositional environment, the flow or erosive environment and the transitional environment. Different benthic associations were related with the defined environment. The shrimp distribution presented a WE pattern, localizing the juvenil individuals towards the W and the adults towards the NE. A relationship among the spatial disposition of the adults with depth and total organic carbon was assessed
Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales
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