Macroalgas de ambientes lóticos da região centro-oeste do Paraná, região sul do Brasil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Population features of the spider crab Acanthonyx scutiformis (Dana 1851) (Crustacea, Majoidea, Epialtidae) associated with rocky-shore algae from southeastern Brazil.

Acanthonyx scutiformis, an endemic species in the Brazilian coast, is commonly found in intertidal rocky-shore algal communities. This study analyzes the population biology of A. scutiformis from Ubatuba region. A total of 371 specimens were collected over one year. Size range was 4.2[long dash]12.7 mm CW (carapace width) for females and 3.7[long dash]15.8 mm CW for males. Females predominated in intermediate size classes, whereas males prevailed in the largest ones. The estimated size when 50% crabs were mature was 10.7 mm CW for males and 8.9 mm CW for females. Sex ratio varied among the demographic groups. The processes that influence A. scutiformis population structure can be related to the different times males and females reach sexual maturity and probably to the distinct predation pressures on each sex during the adult phase.

Efeitos da textura e heterogeneidade de substratos artificiais em função da velocidade da correnteza e da escala temporal sobre as comunidades de macroalgas de ambientes lóticos

Pós-graduação em Ciências Biológicas (Biologia Vegetal) - IBRC

Algas e cianobactérias aerofíticas de fragmentos de floresta estacional semidecidual no noroeste paulista

Pós-graduação em Ciências Biológicas (Biologia Vegetal) - IBRC

Riqueza, abundância e sazonalidade de comunidades de macroalgas em diferentes escalas espaciais em riachos da região centr-sul do estado do Paraná

Conselho Nacional de Desenvolvimento Cientifico e Tecnológico (CNPq)

The effects of habitat complexity and hydraulic conditions on the establishment of benthic stream macroalgae

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Benthic response to upwelling events off the SE Brazilian coast

The main aim of the present study was to evaluate and compare temporal responses of the benthos in 2 continental shelf areas (Cabo Frio and Ubatuba) off the SE Brazilian coast. In Cabo Frio (23 degrees S, 42 degrees W), the western boundary coastal upwelling of the South Atlantic Central Water (SACW) enhances primary productivity, potentially increasing food supply to the benthic communities via sinking of particulate organic carbon (POC). In contrast, POC fluxes in Ubatuba (23 degrees S, 45 degrees W) are expected to be comparatively lower because SACW remains subsurface. We analyzed the temporal and spatial input of phytodetritus (concentration of chlorophyll a in sediments) and the benthic microbial biomass (estimated by ATP-based carbon content in sediments). Median surface chlorophyll concentration was computed for all daily available SeaWiFS images (from 2001 and 2002) to follow chlorophyll a inputs. All parameters used to investigate benthic responses in the study areas showed consistently higher values in Cabo Frio than in Ubatuba. The results showed that benthic response to upwelling may last months, fueling the microbial communities in the Cabo Frio region.

Vertical distribution of benthic invertebrate larvae during an upwelling event along a transect off the tropical Brazilian continental margin

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Distribution of stream macroalgal communities from the mid-western region of Paraná state, southern Brazil: importance of local scale variation

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Evaluation of seasonal dynamics and bioindication potential of macroalgal communities in a polluted tropical stream

Macroalgal communities and environmental variables were analyzed seasonally along a polluted tropical stream in São Paulo State, Brazil, We aimed to improve the knowledge of tropical macroalgal communities, to study the longitudinal and seasonal dynamics of these communities in influenced environments, to evaluate the relationship of algal frequency and abundance with selected environmental variables, and to look for potential macroalgal species indicators. The seasonal abundance pattern was similar to natural or low influenced systems and was mainly determined by rainfall regime. However, community composition was closely related to some chemical water pollution indicators, such as phosphorus and nitrogen compounds. Some species are suggested as potential indicators of organic pollution (e.g. Oscillatoria ornata, Stigeoclonium helveticum and Schizomeris leibleinii), but more detailed studies have to be developed to determine the tolerance limits of these species. on the basis of our results and literature data, the use of occurrence of Oscillatoriales in relation to other orders of Cyanoprokaryota is suggested to be a good indicator of organic pollution in tropical lotic ecosystems.

Changes in coral reef communities and an associated reef fish species, Cephalopholis cruentata (Lacepede), after 30 years on Curacao (Netherlands Antilles)

Using the same methodology and identical sites, we repeat a study dating from 1973 and quantify cover of hard coral species, soft corals, sponges, hard substratum and soft substratum, and density of a commercially important reef fish species, the graysby Cephalopholis cruentata, along a depth-gradient of 3-36 m oil the coral reefs of Curacao. The objective was to determine the multi-decade change in benthic coral reef cover and structural complexity, and their effect oil densities of an associated reef fish species. Total hard coral cover decreased on average from 52% in 1973 to 22% in 2003, representing a relative decline of 58%. During this time span, the cover of hard substratum increased considerably (from 11 to 58%), as did that of soft corals (from 0.1 to 2.2%), whereas the cover of sponges showed no significant change. Relative decline of hard coral cover and of reef complexity was greatest in shallow waters (near the coast), which is indicative of a combination of anthropogenic influences from shore and recent storm damage. Cover of main reef builder coral species (Agaricia spp., Siderastrea siderea, Montastrea annularis) decreased more than that of other species, and resulted in a significant decrease in reef complexity. Although density of C. cruentata was highly correlated to cover of Montastrea and Agaricia in 1973, the loss of coral cover did not show any effect on the total density of C. cruentata in 2003. However, C. cruentata showed a clear shift in density distribution from shallow water in 1973 to deep water in 2003. It call be concluded that the reefs of Curacao have degraded considerably in the last three decades, but that this has had no major effect on the population size of one commercially important coral-associated fish species.

Variance partitioning of deconstructed periphyton communities: does the use of biological traits matter?

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

The influence of landscape on the spatial and temporal distribution of stream macroalgal communities of two types of subtropical biomes

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The roles of environmental conditions and spatial factors in controlling stream macroalgal communities

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)