FOULING COMMUNITY AT FOUR DEPTHS IN GUAIBA ISLAND, RIO DE JANEIRO (BRAZIL)

Este estudo tem como principais objetivos determinar a composição específica e a estrutura das comunidades incrustantes em painéis de PVC (0,20 x 0,20m) a 2, 5, 10 e 15 metros de profundidade. No total 40 taxa se desenvolveram sobre os painéis. Dentre os organismos que ocorreram, exclusivamente, a uma determinada profundidade podemos ressal­tar: Polyandrocarpa sp. (Chordata ) -15 metros, Ascidia interrupta (Chordata), Ulva lactuca, Enteromorpha flexuoxa (Chlorophyta) e Colpomenia sinuosa (Phaeophyta) - ­2 metros. Em 4 estações do ano, foram posicionados painéis extras, para a observação do recrutamento. Algumas das espécies que ocorreram de forma mais freqüente nesses painéis foram: Hincksia mitchelliae (Phaeophyta), Megabalanus coccopoma, Balanus trigonus, B. eburncus (Crustácea), Obelia dichotoma e Ectopleura warreni (Cuidaria). A biomassa dos organismos presentes a 2 e 5 metros foi superior a daqueles que ocorreram a 10 e 15 metros. Foram observadas diferenças significativas nas freqüências dos taxa entre as profundidades e no longo dos 12 meses do experimento.The specific composition and the structure of the fouling community that grew on 4 PVC panels (0.20 x 0.20m) at 2, 5, 10 and 15 meters deep are presented in this paper. During the experiment 40 taxa grew, on the panels as fouling organisms. Some taxa occorred only at one depth: Polyandrocarpa sp. (Chordata ) -15 meters, Ascidia interrupta (Chordata), Ulva lactuca, Enteromorpha flexuoxa (Chlorophyta) and Colpomenia sinuosa (Phaeophyta) - ­2 meters. Extra panels were fixed to observe the recruitment in 4 different seasons. Hincksia mitchelliae (Phaeophyta), Megabalanus coccopoma, Balanus trigonus, B. eburncus (Crustácea), Obelia dichotoma and Ectopleura warreni (Cuidaria) were some of the most frequent species observed on the recruitment panels. The biomass of the organism, present at 2 and 5 meters were higher than those from la and 15 meters. Significant differences were detected on the taxa frequence among the 4 depths and among the 12 experiment months

Contribuição ao inventário das algas marinhas bentônicas de Fernando de Noronha

Resumo O Arquipélago de Fernando de Noronha localiza-se acerca de 546km da cidade de Recife, Pernambuco. A partir de coletas realizadas em julho de 1986, nas zonas supralitoral, mesolitoral e infralitoral, o presente trabalho apresenta a listagem das 106 espécies identificadas, sendo 33 Chlorophyceae, 22 Phaeophyceae e 51 Rhodophyceae, e sua distribuição ao longo de 11 pontos de coleta selecionados do lado noroeste da Ilha de Fernando de Noronha e da Ilha Rata. Dentre as espécies citadas, 25 são referências novas para a região. Comentários s3o feitos a respeito dos grupos de interesse taxonômico e ecológico

Short-term effects of increasing CO2, nitrate and temperature on three Mediterranean macroalgae: Biochemical composition

Short-term effects of increasing pCO(2); 380 ppm (LC) vs. 700 ppm (HC); at different nitrogen levels; 5 mu M nitrate (LN) vs. 50 mu M (HN); on the contents of protein, mycosporine-like amino acids (MAAs), phenolic compounds and total fatty acids, antioxidant activity, calcification and C: N ratios were analyzed in 3 eulittoral Mediterranean macroalgae with different bio-optical characteristics and carbon assimilation efficiencies: Cystoseira tamariscifolia (Heterokontophyta), Ulva rigida (Chlorophyta) and Ellisolandia elongata (Rhodophyta). After acclimation to different pCO(2) and nitrogen conditions for 6 d, the algae were subjected to a 4 degrees C temperature increase for 3 d. Increasing temperature and pCO(2) produced alterations in the biochemical composition of the 3 macroalgae. Short-term variations of protein levels were observed in U. rigida, with clearly decreased values in the HCLN treatment. In C. tamariscifolia, protein decreased after the temperature increase but only under LC. The interaction of temperature and N affected phenolic compounds only in U. rigida and the content of MAAs in E. elongata. The functional patterns of the 3 macroalgae in response to the pCO(2), nitrogen and temperature regimes may be explained in terms of their bio-optical characteristics and antioxidant activity. The vulnerability and acclimation of the 3 species to the expected variations of climate change factors are discussed