Recrutment project: spatial variation in the photosynthesis vs. light (P-I) curves of benthic algae in the Arraial do Cabo region, RJ

Abstract

As part of a research program about the "Biological consequences of oceanographic process affecting the coastal benthic community" (Recrutment Project) several photosynthesis vs. irradiance (P-I) curves were measured during July/88, in the dominant species of benthic algae in the Arraial do Cabo region, RJ. Photosynthesis was measured by oxygen exchange in simulated "in situ" conditions using a gradient of light with temperature controlled. The hyperbolic tangent model. of Jassby & Platt (1976) was used to simulated the data. Maximum values of Pmax (the specific photosynthetic rate at saturating light) were observed in the Jacon g station on Ulva faciata (36 mgC/gdw/h). At Búzios station, there was a decrease in the saturation point (Ik) for the species living in the sublittoral. Our results showed a horizontal (among stations) and vertical (among depths) variation in the parameters of P-I curves in the Arraial do Cabo region. Primary Production of benthic algae in the Arraial do Cabo (RJ) region.