scholarly journals Hydrology, plankton, and corals of the Maracajaú reefs (Northeastern Brazil): an ecosystem under severe thermal stress

2009 ◽  
Vol 52 (3) ◽  
pp. 665-678 ◽  
Author(s):  
Elga Miranda Mayal ◽  
Sigrid Neumann-Leitão ◽  
Fernando Antônio do Nascimento Feitosa ◽  
Ralf Schwamborn ◽  
Tâmara de Almeida e Silva ◽  
...  
Keyword(s):  
Thermal Stress ◽  
Rainy Season ◽  
Isotope Analysis ◽  
Northeastern Brazil ◽  
Mesozooplankton Community ◽  
Baseline Information ◽  
Wet Weight ◽  
Plankton Communities ◽  
Reef Ecosystem ◽  
Reef Formation

This study provides baseline information on the hydrological conditions and on the coral and plankton communities at the Maracajaú reef ecosystem (Northeastern Brazil). Studies were performed from February to June 2000, covering the transition from dry to rainy season. In this area, there is an offshore coral reef formation, where corals were observed in loco; the water samples were collected to obtain the hydrological and plankton data. Six scleractinian species were identified. Stable isotope analysis on the carbonate fraction of Favia gravida fragments showed that these corals were under severe thermal stress. Chlorophyll-a varied from 1.1 to 9.3 mg m-3, with higher values during the rainy season. Average zooplankton wet weight biomass were 117.0 (microzooplankton) and 15.7 mg m -3(mesozooplankton). A total of 136 Phytoplankton and 61 zooplankton taxa were identified. Seasonal forcing determined the phyto-micro-and mesozooplankton community structure, rather than the coastal-offshore gradient.

scholarly journals Composition and diversity of anurans in the Restinga of the Conde municipality, northern coast of the state of Bahia, northeastern Brazil

2016 ◽  
Vol 16 (3) ◽  
Author(s):  
Felipe Augusto Trindade Gondim-Silva ◽  
Alessandra Rodrigues Santos Andrade ◽  
Rafael Oliveira Abreu ◽  
Jamile Santos Nascimento ◽  
Geovane Paixão Corrêa ◽  
...  
Keyword(s):  
Species Richness ◽  
Species Diversity ◽  
Species Composition ◽  
Rainy Season ◽  
Dominant Species ◽  
The State ◽  
Northeastern Brazil ◽  
Freshwater Wetland ◽  
Northern Coast ◽  
Anuran Species

Abstract The Conde municipality is located in the northern coast of the state of Bahia (NC), northeastern Brazil, and is part of the Atlantic Tropical domain. The anuran fauna of the northern portion of the NC is still poorly known if compared to the southern portion. The Restinga is one of the predominant environments of the coastal plains of the NC and it is characterized essentially by presenting sandy soil covered by herbaceous and shrubby vegetation. The objective of this study was to determine the anuran species composition and diversity for the Restinga of the Conde municipality. Sampling was carried out at night by active search over four periods of five consecutive days each, two over the 'main rainy season' and two in a 'lesser rainy season', using 14 sample units (SUs) and five extra sample plots (EPs). We calculated dominance and species diversity using the Berger-Parker and Shannon-Wiener H' indices, respectively. We used accumulation curves and the Jackknife 1 estimator to estimate anuran species richness, considering only the data obtained from the SUs. We recorded 713 anuran specimens distributed within 33 species, 13 genera and five families (Bufonidae, Craugastoridae, Hylidae, Leptodactylidae and Microhylidae). The Hylidae and Leptodactylidae families had the highest species richness. Considering only the SUs (Jackknife 1 estimator in brackets), we recorded 28 species in the study area (33.9 ± 2.3), 13 in Shrubby Vegetation Zones - SVZ (20.8 ± 2.9) and 25 in Freshwater Wetland Zones - FWZ (28.9 ± 1.9). The abundance and species diversity of the FWZ (n = 638 specimens; H'= 2.4) were higher than those recorded for the SVZ (n = 52 specimens; H' = 1.9). The SVZ and FWZ showed distinct dominant species, wherein Pristimantis paulodutrai was the dominant species in SVZ and Scinax fuscomarginatus in FWZ. The Restinga of the Conde municipality stands out as the one with the highest anuran species richness already recorded considering only SVZ and FWZ. Moreover, its anuran species composition represented 55% of the anuran species known for the NC and included taxa common to three different morphoclimatic domains (Tropical Atlantic, Cerrado and Caatinga).

scholarly journals Seasonal drought prediction for semiarid northeastern Brazil: verification of six hydro-meteorological forecast products

2018 ◽  
Vol 22 (9) ◽  
pp. 5041-5056 ◽  
Author(s):  
José Miguel Delgado ◽  
Sebastian Voss ◽  
Gerd Bürger ◽  
Klaus Vormoor ◽  
Aline Murawski ◽  
...  
Keyword(s):  
Rainy Season ◽  
Meteorological Drought ◽  
Skill Score ◽  
Hydrological Drought ◽  
Northeastern Brazil ◽  
Drought Indices ◽  
Monthly Precipitation ◽  
Seasonal Forecasts ◽  
Seasonal Drought ◽  
Drought Prediction

Abstract. A set of seasonal drought forecast models was assessed and verified for the Jaguaribe River in semiarid northeastern Brazil. Meteorological seasonal forecasts were provided by the operational forecasting system used at FUNCEME (Ceará's research foundation for meteorology) and by the European Centre for Medium-Range Weather Forecasts (ECMWF). Three downscaling approaches (empirical quantile mapping, extended downscaling and weather pattern classification) were tested and combined with the models in hindcast mode for the period 1981 to 2014. The forecast issue time was January and the forecast period was January to June. Hydrological drought indices were obtained by fitting a multivariate linear regression to observations. In short, it was possible to obtain forecasts for (a) monthly precipitation, (b) meteorological drought indices, and (c) hydrological drought indices. The skill of the forecasting systems was evaluated with regard to root mean square error (RMSE), the Brier skill score (BSS) and the relative operating characteristic skill score (ROCSS). The tested forecasting products showed similar performance in the analyzed metrics. Forecasts of monthly precipitation had little or no skill considering RMSE and mostly no skill with BSS. A similar picture was seen when forecasting meteorological drought indices: low skill regarding RMSE and BSS and significant skill when discriminating hit rate and false alarm rate given by the ROCSS (forecasting drought events of, e.g., SPEI1 showed a ROCSS of around 0.5). Regarding the temporal variation of the forecast skill of the meteorological indices, it was greatest for April, when compared to the remaining months of the rainy season, while the skill of reservoir volume forecasts decreased with lead time. This work showed that a multi-model ensemble can forecast drought events of timescales relevant to water managers in northeastern Brazil with skill. But no or little skill could be found in the forecasts of monthly precipitation or drought indices of lower scales, like SPI1. Both this work and those here revisited showed that major steps forward are needed in forecasting the rainy season in northeastern Brazil.

scholarly journals Limnological characteristics of a reservoir in semiarid Northeastern Brazil subject to intensive tilapia farming (Orechromis niloticus Linnaeus, 1758)

2014 ◽  
Vol 26 (1) ◽  
pp. 47-59 ◽  
Author(s):  
Luis Artur Valões Bezerra ◽  
Walt Disney Paulino ◽  
Danielle Sequeira Garcez ◽  
Helena Becker ◽  
Jorge Iván Sánchez-Botero
Keyword(s):  
Chlorophyll A ◽  
Rainy Season ◽  
Dry Season ◽  
T Test ◽  
Northeastern Brazil ◽  
Human Consumption ◽  
Temperature Conductivity ◽  
Sampling Locations ◽  
Chemical Variability ◽  
Physical And Chemical

AIM: There is currently no consensus regarding the physical and chemical variability of tropical reservoirs. In semiarid Northeastern Brazil, reservoirs are among other things used for human consumption, industrial water supply and intensive fish farming, all of which can impact water quality. The objective of this study was to evaluate the physical and chemical variability of the water in Sítios Novos, a reservoir in semiarid Northeastern Brazil, comparing samples collected in areas of intensive tilapia (Oreochromis niloticus) farming to samples from areas not directly impacted by aquaculture, in both the dry and the rainy season. METHODS: Between October 2010 and July 2011, data were collected on temperature, conductivity, pH, turbidity, salinity, chlorophyll a, dissolved oxygen, oxygen demand, total phosphorus and total nitrogen levels in the water column using a multiparametric probe at four different sampling locations. Physical and chemical differences between the four locations were evaluated with the Kruskal-Wallis (KW) test and Dunn's post test, while the t test, followed by Welchʼs correction, was used to compare samples collected in different seasons. RESULTS: No influence of intensive aquaculture was detected when comparing sampling locations near fish farms (180C and 300C) to locations not directly impacted by aquaculture (LIMN1, near the dam, and LIMN2, near the debouch of the São Gonçalo river). However, the sampling locations differed significantly (p<0.05) with regard to conductivity, pH, turbidity and chlorophyll a levels. CONCLUSIONS: The physical and chemical variability was greater between seasons than between locations when the data were analyzed with the t test. That analysis showed significant differences for 22 of 40 comparisons between the 10 physical and chemical parameters in the two seasons at the four sampling locations. In conclusion, the physical and chemical variability registered for the Sítios Novos reservoir throughout the study period indicates morphometric, meteorological and hydrological heterogeneity, with emphasis on the differences between LIMN2 and the other three sampling locations and between the rainy season and the dry season. According to the calculated trophic status index, the reservoir is supereutrophic in the rainy season and supereutrophic to hypereutrophic in the dry season.

scholarly journals Spatial and temporal distribution in two anuran communities in the Chapada do Araripe, Northeastern Brasil

2016 ◽  
Vol 16 (1) ◽  
Author(s):  
Cristiana Ferreira-Silva ◽  
Deivid Batista de Oliveira ◽  
Herivelto Faustino de Oliveira ◽  
Robson Waldemar Ávila
Keyword(s):  
Leaf Litter ◽  
Rainy Season ◽  
Temporal Distribution ◽  
Water Bodies ◽  
Northeastern Brazil ◽  
Microhabitat Use ◽  
Spatial And Temporal Distribution ◽  
Humid Forest ◽  
Temporal Occurrence ◽  
Chapada Do Araripe

In this study, we report the temporal occurrence and habitat and microhabitat use by anurans in two areas located in one highland marsh (brejo-de-altitude) in northeastern Brazil. Fieldwork was carried out between September 2011 and September 2012. The recorded anurans belong to 14 species distributed in five families: Hylidae (six), Leptodactylidae (five), Bufonidae, Odontophrynidae and Pipidae (one each). Vocalization activity was seasonal and concentrated in the wetter and warmer months, but correlated to rainfall only in the top in the Chapada do Araripe. Richness and abundance of calling anurans were lower in the humid forest of the slope than in Cerradão area in the top of the Chapada do Araripe. Scinax x-signatus vocalized during nine months, and along with Dendropsophus soaresi, Phyllomedusa nordestina and Physalaemus cuvieri presented the longest periods of vocalization with the highest number of species vocalizing in at the height of the rainy season. Males were recorded vocalizing in nine different microhabitats, Adenomera sp. uses leaf litter and P. cuvieri the edge of water bodies as calling site both two sampled areas. Differences in richness and abundance of anurans between the two habitats are probably due to physical characteristics, such as presence of lentic environments.

scholarly journals Reproduction of a whiptail lizard (Ameivula ocellifera, Teiidae) from a coastal area in northeastern Brazil

2014 ◽  
Vol 86 (3) ◽  
pp. 1263-1272 ◽  
Author(s):  
DJAN ZANCHI-SILVA ◽  
DIVA M. BORGES-NOJOSA ◽  
CONRADO A.B. GALDINO
Keyword(s):  
Body Size ◽  
Clutch Size ◽  
Coastal Area ◽  
Rainy Season ◽  
Female Body ◽  
The State ◽  
Northeastern Brazil ◽  
Egg Volume ◽  
Female Reproduction ◽  
Female Body Size

The reproductive ecology of Ameivula ocellifera was studied from September 2009 to August 2010 in a coastal area of the state of Ceará, Brazil. Females reproduced continuously throughout the year, with a peak at the end of the rainy season. Even though there was a predominance of pre-reproductive individuals in the sample, gonadal activity of males peaked synchronously to female reproduction. Mean clutch size was 1.98 ± 0.56 and positively associated with female body size, while mean egg volume was 510.54 ± 84.29 mm3 and unrelated to female body size. We did not find any association between clutch size and average egg volume.

scholarly journals First record of Voyria caerulea Aubl. (Gentianaceae), a mycoheterotrophic plant, in Maranhão state, northeastern Brazil

Check List ◽  
2018 ◽  
Vol 14 (5) ◽  
pp. 833-837
Author(s):  
Alessandro Wagner Coelho Ferreira ◽  
Maria Fernanda Calió ◽  
Wagner Ribeiro da Silva Junior ◽  
Maycon Jordan Costa da Silva ◽  
Miguel Sena de Oliveira ◽  
...  
Keyword(s):  
Geographic Distribution ◽  
Rainy Season ◽  
First Record ◽  
The State ◽  
Identification Key ◽  
Northeastern Brazil ◽  
Gallery Forest ◽  
Taxonomic Description

We report the first record of Voyria caerulea from the state of Maranhão, northeastern Brazil. A fertile specimen was collected in a gallery forest during the rainy season, within the boundaries of the municipality of São Raimundo das Mangabeiras. This find contributes to the knowledge on the micoheterotrophic flora of Maranhão and expands the geographic distribution of this species in Brazil. We also present a taxonomic description, illustrations, an occurrence map of the newly found population, and an identification key for all the species of Voyria that occur in Maranhão.

scholarly journals Individual niche trajectories in nesting green turtles on Rocas Atoll, Brazil: an isotopic tool to assess diet shifts over time

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Karoline Fernanda Ferreira Agostinho ◽  
Leandro Rabello Monteiro ◽  
Ana Paula Madeira Di Beneditto
Keyword(s):  
Trophic Ecology ◽  
Isotope Analysis ◽  
Trophic Niche ◽  
Northeastern Brazil ◽  
Diet Shift ◽  
Isotopic Niche ◽  
Temporal Window ◽  
Temporal Dimension ◽  
Green Turtles ◽  
Diet Shifts

Abstract In this study, multi-tissue (yolk and carapace) stable isotope analysis was used to assess individual isotopic niche trajectories of nesting green turtles on Rocas Atoll, off northeastern Brazil, and to reveal a diet shift in the temporal dimension. The diet trajectories of individual green turtles were highly directional, with a stronger component towards decreasing values of δ15N from carapace to yolk. When the green turtles are in their foraging sites (temporal window measured by the yolk samples), they are more herbivores. Conversely, in a broader temporal window, the green turtles demonstrate a carnivore-omnivore strategy, such as represented by heavier δ15N values in the carapace. This finding confirms a temporal diet shift. This is the first study that applies trophic niche trajectories for sea turtles, adding a new isotopic tool to understand the trophic ecology of these migrant animals.

scholarly journals Forensically relevant diptera species associated with pig carcasses in a Brazilian city exposed to high rates of homicide

2021 ◽  
Vol 61 ◽  
pp. e20216101
Author(s):  
Tadeu Morais Cruz ◽  
Taciano Moura Barbosa ◽  
Patrícia Jacqueline Thyssen ◽  
Simão Dias Vasconcelos
Keyword(s):  
Geographical Distribution ◽  
Rainy Season ◽  
Forensic Entomology ◽  
The Other ◽  
Northeastern Brazil ◽  
Forest Fragments ◽  
Anthropogenic Action ◽  
Forested Areas ◽  
Rapid Dissemination ◽  
Pig Carcasses

Cities in northeastern Brazil experience extreme rates of unsolved homicides, a situation that stimulates innovative procedures in the police work, such as forensic entomology. We surveyed necrophagous insects associated with carrion in a city exposed to high rates of homicides in Northeastern Brazil. The experiments were carried out in a rainforest fragment located in Recife, State of Pernambuco. Two pig carcasses were used as models, one in the dry and the other in the rainy season. The collection of adults was performed daily until the complete skeletonization of the carcasses. At least 32 Diptera species from the families Calliphoridae, Muscidae, Sarcophagidae, Fanniidae, Phoridae, Anthomyiidae, Piophilidae, and Stratiomyidae were registered, some of which have been previously documented on cadavers. A high richness of Diptera species was registered in all stages of decomposition. A strong overlap in the occurrence of most species was observed, which invalidates a defined entomological succession on the carcasses. Two species stood out in terms of abundance: Ophyra chalcogaster (Muscidae) and Chrysomya albiceps (Calliphoridae). The ubiquity of Hemilucilia semidiaphana (Calliphoridae) seems to confirm its preference for forest fragments exposed to low anthropogenic action. Our data contribute to expand the knowledge on the geographical distribution of forensically relevant species in the region and confirm the rapid dissemination of invasive Chrysomya species in forested areas.

scholarly journals PADRÕES ATMOSFÉRICOS E OCEÂNICOS ASSOCIADOS A EVENTOS EXTREMOS NA BACIA AMAZÔNICA: UMA ANÁLISE DE COMPOSIÇÃO BASEADA NOS EPSÓDIOS SECOS DE 1982/83, 2004/05 E 2009/10

2017 ◽  
Vol 39 (2) ◽  
pp. 423
Author(s):  
Franci Flores Vargas ◽  
José Augusto Paixão Veiga
Keyword(s):  
South America ◽  
Rainy Season ◽  
Amazon Basin ◽  
Moisture Flux ◽  
Northern Region ◽  
Northeastern Brazil ◽  
Specific Humidity ◽  
Trade Winds ◽  
The North ◽  
Variable Precipitation

This study aimed to determine the atmospheric and oceanic patterns related to changes in precipitation over the Amazon basin during the episodes of extreme drought occurred in the years of 1982/83, 2004/2005 and 2009/10. Data from the zonal and meridional components of the wind vector, wind speed, omega, specific humidity, precipitation and sea surface temperature was used. The data was obtained from the reanalysis-2 NCPE/NCAR (except for the variable precipitation which was obtained from the CMAP). The anomalous composition method was used to determine the atmospheric and ocean fields that were characteristic of episodes of intense drought. The results show a deficit in rainfall in the rainy pre-season (SON) in part of the northern region of South America and northeastern Brazil. The lower level of rainfall also persists during the rainy season (December to April). Associated with these anomalous patterns of rainfall, positive anomalies of SST were observed which were similar to El Niño events, followed by anomalous subsidence in the Amazon. In the rainy pre-season, wind divergence over the state of Amazonas and the north of South America was observed. During the rainy season, the divergence in streamlines shows the weakening of the northeast trade winds. In addition, the anomalous divergence of vertically integrated moisture flux reveals consistency with rainfall deficits in theipre and rainy season in the Amazon basin.

scholarly journals Seasonal influence on testicular morphophysiological parameters of bat Carollia perspicillata in fragments of the Atlantic Forest, northeastern Brazil

2019 ◽  
Vol 39 (6) ◽  
pp. 429-433
Author(s):  
Maria J.G. Arandas ◽  
Álvaro A.C. Teixeira ◽  
Valéria W. Teixeira ◽  
Fabricya R. Silva ◽  
Ketsia S.N. Marinho ◽  
...  
Keyword(s):  
Atlantic Forest ◽  
Rainy Season ◽  
Leydig Cells ◽  
Northeastern Brazil ◽  
Adult Males ◽  
Histomorphometric Analysis ◽  
Reproductive Seasonality ◽  
Carollia Perspicillata ◽  
Androgenic Activity ◽  
High Precipitation

ABSTRACT: Bats belong to the order Chiroptera, family Phyllostomidae, and present a wide diversity of reproductive strategies. However, information on the reproductive biology of male bats is scarce, mainly in the Northeast Region of Brazil. Thus, this study evaluated the seasonal testicular histomorphometry of the bat Carollia perspicillata in fragments of the Atlantic Forest in Pernambuco state. To this end, adult males were collected, euthanized for removal of the testicles, and later submitted to a routine histological technique. Histomorphometric analysis included assessment of the areas of tubular and intertubular compartment occupation, as well as quantification of spermatocytes, rounded spermatids, elongated spermatids, and Sertoli and Leydig cells. Results indicated that this bat species presents reproductive seasonality, because significantly higher averages of the testicular parameters were observed in the rainy season, which is a period of greater availability of food resources. Such inferences indicate that there is a synchrony between peak spermatogenesis and hormonal inversion in the months of high precipitation; furthermore, a higher carrying capacity of the Sertoli cells is noted. C. perspicillata males possibly present greater sperm and androgenic activity in the rainy season, associated with increased tubular area and number of spermatogenic cells, as well as with the intertubular area and number of Leydig cells, respectively.

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