Percentages of nitrogen and phosphorus in 10 species of seaweeds (6 green and 4 red algae) were monitored from 1997 to 2004 by seasonal sampling in Guanabara Bay, South-eastern Brazil. The species did not show consistent variations in tissue N, P and N:P that related to annual cycles. Throughout this study, higher percentages of tissue N and P were found in Bostrychia radicans and Grateloupia doryphora (red algae) and lower in Cladophora rupestris and Codium decorticatum (green algae). In November 1999, the Icaraí Submarine Sewage Outfall became operational, resulting in a reduction of visual pollution in the area and an improvement in the local quality of seawater for recreational use. Measurements of dissolved nutrients at the sampling site did not indicate significant changes in concentrations after the commissioning of the submarine sewage outfall; however, tissue P and N:P ratio of most of species were significantly lower than in the first two years of this survey. Variations in tissue nitrogen throughout this study were not significant, except for G. doryphora in some comparisons. Results show that seaweeds function very well as monitors of environmental changes in Guanabara Bay. Experimental data are needed to identify possible environmental processes which are promoting changes in chemical composition of the local seaweed populations.

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Bamboo is one of the most easily available resources found in forests. Due to their long periods of vegetative growth and rapid biomass gains, bamboo species could show a significant potential for responding to elevated atmospheric CO 2 concentrations. The purpose of this study was to investigate the effects of an increased CO 2 concentration on selected physiological and biochemical parameters of the bamboo Aulonemia aristulata. After 7 weeks, plants grown under an elevated CO 2 concentration showed an increase of 77% in photosynthesis, 56% in tillering, 104% in leaf area, 92% in height and 91% in total biomass. These plants also had a lower stomatal conductance ( (40%) and higher water use efficiency (62%). Physiological responses such as adjustment in the photosynthetic rates, carbon gain and water relations shown by A. aristulata in response to increased CO 2 concentration could promote a higher dominance of this bamboo species in a global change scenario. This dominance could affect the species composition, structure and function of tropical forests.

The seaweeds Chaetomorpha antennina, Gymnogongrus griffithsiae and Ulva fasciata were studied regarding tissue concentrations of total nitrogen, total phosphorus, total protein, hydrosoluble protein, total carbohydrate, chlorophyll a and total carotenoid throughout a 39-month survey in two coastal environments of Rio de Janeiro State, Brazil. One of the sites (Itapuca Stone) has high concentrations of dissolved nutrients and an intense long-term process of cultural eutrophication; the second site (Bananal Inlet) is thought to have lower concentrations of dissolved nutrients and no relevant anthropic impact. Seaweeds experienced changes in the concentrations of the substances in the thalli; however they did not show any cyclic seasonal pattern, except for pigments, with lower values in summer in both sites. The differences found for each species in each sampling at the sites were small (e.g. U. fasciata, more total nitrogen at Itapuca Stone) or absent (e.g. C. antennina, no significant differences for hydrosoluble protein in the sites). Differences in the concentrations of dissolved nutrients in the sites did not generate contrasting chemical profiles in the seaweeds. There is no evidence of nitrogen-or phosphorus-limitation in any season. It is presumable that the concentrations of dissolved nutrients at the nutrient-poorer site are sufficient to generate high concentrations of the substances in the thalli of the species tested, similar to the concentrations measured in the eutrophic site. Experimental data are needed to elucidate the factors that promote the success of the species tested under contrasting nutrient availability and environmental disturbance.

Highlights Even slow growing mammary lesions in a male child may be malignant. Secretory breast cancer positive for estrogen and progesterone receptors is very rare in a male child. Secretory breast cancer after surgical excision usually does not require adjuvant therapy.