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The present survey of Bahia de San Quintin in Baja California fulfills two pimary purposes: a search for basic information on an unpolluted enclosure as near southern California as posible, and the initiation of comparative investigations. This report forms an introduction to a series of articles to be published on the geology, hidrography and benthic life of the bay, an includes those descriptive features not being treated elsewhere. This study report 36 species of algae (Twenty-three red algae, nine green algae, four brown algae and one blue-green algae). An a 11 species of saltmarsh plants.

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De Junio a diciembre de 1982 se tomarón muestras mensuales para la determinación de la biomasa de las macroalfas flotantes y epífitas de una pradera de Zostera marina L. en Bahía Falsa, san Quintín. Se instalaron tres transectos: -0.95 m (I),-0.80 m (II), y -0.65 m (III) con respecto al nivel medio del mar y se colectaron cinco réplicas de 20 x 20 cms en cada transecto. Simultáneramente se colectaron y preservaron ejemplares para la identificación taxonómica. Durante el otoño se presentó un aumento notable en la biomasa que se adjudica a las algas verdes. Si bien la biomasa expresada en g peso seco/m² representa un valor intermedio a los reportados en la literatura, al expresarla como porcentaje de la biomasa aérea total de Zostera marina en San Quintín, representa, en promedio, un 55% de ésta. Por otra parte, no hubo diferencia significativa entre los transectos. El estudio taxonómico arrojó un total de diez géneros y once especies, de las cuáles son cinco algas verdes, una laga parda y cuatro rojas. Se reportan por primera vez para la región: Enteromorpha clathrata, Giffordia sandriana y Cryptopleura spatulata, elevando así el número total a 30 géneros, 39 especies y una variedad. La forma de vida de la mayoría de las macroalgas encontradas fue formando grandes masas sobre la pradera de Z.marina y el sediemento. Se infiere que éstas algas no se originan in situ, sino que son transportadas al plano fngoso por efectos mécanicos del moviemiento del agua.

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This study attempted to survey one of the principal benthic marine plant communities od California is that dominated by the largest known marine algae Macrocystis pyrifera , through s portion of its range, observation about the floristic composition of this community and to distinguish, record and characterize its prominent plant. The major emphasis in this work has been placed on the illustrations of the prevalent plants and of a key to aid in their identification.

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The present survey of Bahia de San Quintin in Baja California fulfills two primary purposes: a search for basic information on an unpolluted enclosure as near southern California as posible, and the initiation of comparative investigations. This report forms an introduction to a series of articles to be published on the geology, hidrography and benthic life of the bay, an includes those descriptive features not being treated elsewhere.

Algae and Eel grass were collected by SCUBA diving, wading in tidal shallows and shore collecting. So few algae were recovered in the benthic grab samples that is belived that most of these algae in the bay are concentrated in a narrow belt forming the margin of the bay. A transect of samples was made across the northwestern marsh of the east arm starting on bare soil at the edge of the marshe next to a dirt road. Eighteen samples were taken 10 meters apart seaward of that point. This transect provides a record of the density of vegetation across the marsh for future refence studies. The samples were collected with a post hole digger havin a capacity of 3080 cc, the sample forming a cylinder of 20 cm length and 114 cm diameter.