Composition and spatio-temporal variation in the density of the Brachyura (Decapoda, Pleocyemata) in the rocky substrates of an Amazonian estuary

Crustaceana ◽  
2016 ◽  
Vol 89 (13) ◽  
pp. 1447-1466 ◽  
Author(s):  
Priscila S. V. Nóbrega ◽  
Jussara M. Martinelli-Lemos

The present study investigated the composition, spatio-temporal distribution, and the influence of temperature and salinity on the density of brachyurans associated with rocky substrates in an estuary of the Brazilian Amazonian coast. Specimens were collected monthly at four sites representing the two margins (profiles), zones (inner and outer estuary) and the lower and upper mediolittoral portions at each site of the Marapanim estuary. A total of 14 species were collected and multivariate analyses revealed that the species composition varied systematically between zones, margins, mediolittoral sectors and seasons, with the more saline zone, the most eroded margin, the lower mediolittoral, and the rainy season all being characterized by higher densities and a more homogeneous distribution of species. In general, high densities of brachyurans, but low species richness, and marked dominance characterized the sites. Salinity proved to play an important role in the structuring of the community.

2016 ◽  
Vol 16 (3) ◽  
Author(s):  
Felipe Augusto Trindade Gondim-Silva ◽  
Alessandra Rodrigues Santos Andrade ◽  
Rafael Oliveira Abreu ◽  
Jamile Santos Nascimento ◽  
Geovane Paixão Corrêa ◽  
...  

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).


2012 ◽  
Vol 60 (2) ◽  
pp. 233-243 ◽  
Author(s):  
Thassya Christina dos Santos Schmidt ◽  
June Ferraz Dias

The Sciaenids have among the highest species richness, numerical abundance and biomass of any family of fishes along the Brazilian coast. The aim of this study was to analyze the composition and spatial and temporal distribution of as well as the influence of temperature, salinity and depth on the sciaenid assemblage of Santos Bay. A total of 29,306 individuals belonging to 13 genera and 21 species were captured, between November 2004 and December 2005, with Stellifer rastrifer representing 70.4% of the total composition. Highest abundance and biomass occurred on the east side of the bay, and the highest species richness occurred near the mouth of the Santos Channel, which was also the site with least similarity to the other sites. Highest abundances occurred in April 2005 and lowest in September 2005. Key environmental factors influencing distribution of sciaenids were depth and temperature.


2018 ◽  
pp. 28-32
Author(s):  
TRAICHE ABDERRAOUF, BELHAOUARI BENKHEDDA ◽  
ROUEN-HACEN OMAR

During this study we evaluated the spatio-temporal distribution of macroalgae in the western Algerian coast. This work was carried out in the intertidal zone near the municipality of Tenes. We carried out a seasonal sampling from July 2016 to April 2017, at four different sites. Nine species were identified. The highest species richness was observed in summer and early autumn. The most abundant algae observed were Ulva et Cystoseira. Ulva alga achieved the highest recovery rate 60,33% in Spring. Laurencia obtusa and Spongomorpha arcta were the least abundant. Algae of economic interest have been observed in the coast of Tenes.


Abstract We present a climatological study of aerosols in four representative Caribbean islands based on daily mean values of aerosol optical properties for the period 2008- 2016, using the Aerosol Optical Depth (AOD) and Ångström Exponent (AE) to classify the dominant aerosol type. A climatological assessment of the spatio-temporal distribution of the main aerosol types, their links with synoptic patterns and the transport from different sources is provided. Maximum values of AOD occur in the rainy season, coinciding with the minimum in AE and an increased occurrence of dust, while the minimum of AOD occurs in the dry season, due to the predominance of marine aerosols. Marine and dust aerosol are more frequent in the easternmost islands and decrease westwards due to an increasing of continental and mixture dust aerosols. Therefore, the westernmost station displays the most heterogeneous composition of aerosols. Using a weather type classification, we identify a quantifiable influence of the atmospheric circulation in the distribution of Caribbean aerosols. However, they can occur under relatively weak and/or diverse synoptic patterns, typically involving transient systems and specific configurations of the Azores High that depend on the considered station. Backward trajectories indicate that dry-season marine aerosols and rainy-season dust are transported by air parcels travelling within the tropical easterly winds. The main source region for both types of aerosols is the subtropical eastern Atlantic, except for Cuba, where the largest contributor to dry-season marine aerosols is the subtropical western Atlantic. Different aerosol types follow similar pathways, suggesting a key role of emission sources in determining the spatio-temporal distribution of Caribbean aerosols.


2009 ◽  
Vol 83 (1) ◽  
pp. 69-76 ◽  
Author(s):  
L. Gargouri Ben Abdallah ◽  
N. Trigui El Menif ◽  
F. Maamouri

AbstractCercaria lata (Digenea, Faustulidae), discovered by Lespés (1857) in Tapes decussata (L.) in the basin of Arcachon, was found for the first time, from the eastern Mediterranean, in the same lamellibranch from Tunisia (Bizerte and Tunis lagoons and Gulf of Gabes). These cercariae develop in daughter sporocysts, which develop in mother sporocysts in the gonads. Daughter sporocysts are observed in the gonads and sometimes in the digestive gland. A redescription and the behaviour of the naturally emerging cercariae and spatio-temporal distribution of the sporocysts are reported. A comparative study using multivariate analyses associated with morphology, biology and seasonality confirm the distinctness of Cercaria lata and the cercaria of Cercaria pectinata from Donax trunculus.


Environments ◽  
2019 ◽  
Vol 6 (5) ◽  
pp. 57 ◽  
Author(s):  
Nguon Vichet ◽  
Kensuke Kawamura ◽  
Dung Phan Trong ◽  
Nguyen Van On ◽  
Zhe Gong ◽  
...  

In Cambodia and the Vietnamese Mekong Delta, floods commonly occur during the rainy season, and a better understanding of their spatio-temporal distribution is important for both disaster prevention and the improvement of agricultural production. This study investigated spatio-temporal flood inundation and land cover change from 2002 to 2013 in the southern part of Cambodia using Terra satellite on-board Moderate Resolution Imaging Spectroradiometer (MODIS) images. The algorithm for flood inundation detection, WFFI (Wavelet-based Filter for detecting spatio-temporal changes in Flood Inundation) was used, and the parameters were modified to fit the present study. The estimated inundation areas were validated using eight Landsat images. In a comparison between the original and modified WFFIs, the modified WFFI (70–96%) exhibited better accuracy than the original WFFI (30–70%). Overall, the temporal change in the flood inundation area presented a decreasing trend, and a link to the in-situ observed water level showed a decreasing trend during the rainy season. Furthermore, the estimated flood inundation exhibited a significant delay since 2008. Based on the yearly land cover MODIS product, the permanent water body and wetland areas decreased, whereas the cropland areas increased. This was as a result of increased agricultural productivity. However, water shortage was the major obstacle to increasing agricultural productivity, and it also had a negative impact on aquatic ecology, such as fish spawning grounds.


2007 ◽  
Vol 28 ◽  
pp. 123-133 ◽  
Author(s):  
Leif Nøttestad ◽  
Ole Arve Misund ◽  
Webjørn Melle ◽  
Bente K. Hoddevik Ulvestad ◽  
Kjell Arild Orvik

2020 ◽  
pp. 7-13
Author(s):  
Titis Furi Djatmikowati ◽  
Dini Wahyu Yudianingtyas ◽  
Haeriah Haeriah

Three among five Provinces (South Sulawesi, West Sulawesi and Gorontalo) in Sulawesi island, Indonesia are endemic area of anthrax disease. The aim of this study was to describe the dynamic of anthrax during 2015-2018 and identified risk area in Sulawesi. We determined case of anthrax disease from passive-active surveillance data Disease Investigation Center Maros (DIC Maros) during 2015-2018. Spatial distribution describe by mapping using Quantum Geographic Information System (QGIS), the temporal distribution describe using epidemic curve and we calculated the proportion of animal infected of anthrax. There were thirty-three cases of anthrax spreaded into three Provinces in Sulawesi, there were twenty one cases in South Sulawesi (63.6%), nine cases in Gorontalo (27.3%) and three cases West Sulawesi (9.1%). There were eleven cases (33.3%) in 2015, fifteen cases (45.5%) in 2016, four cases (12%) in 2017 and three cases (6%) in 2018. Anthrax occured respectively in dry season in South Sulawesi and Gorontalo, different with West Sulawesi anthrax occured in rainy season. The proportion of the animal infected were 87% in cattle, 7% in horse, 3% goat and 3% in deer. Vaccination of anthrax in South Sulawesi and Gorontalo should be conducted in May; in Polewali Mandar, West Sulawesi in Februari.


2013 ◽  
Vol 6 (1) ◽  
pp. 09-22 ◽  
Author(s):  
Alexandre Ururahy-Rodrigues ◽  
José Albertino Rafael ◽  
José Roberto Pujol-Luz

One of the must forensic importance insect families is Calliphoridae (Diptera) and different species of this family were used to demonstrate the efficiency of the experimental model used in this study. The experiments were performed with domestic pig models (approximately 60 kg) in Adolpho Ducke Forest Reserve (Manaus, Amazonas). To minimize the effect of repeated samplings in the same model (a result of pseudoreplication), two models were used to answer two questions: 1) What is the species composition and temporal distribution of Calliphoridae adults? 2) What is the species composition and temporal distribution of Calliphoridae that effectively colonized the carcass? Six pseudoreplicates were studied in three periods: from 06/30/2005 to 07/30/2005 (less rainy season), from 10/18/2005 to 11/17/2005 (transition period between the two seasons) and from 03/15/2006 to 04/14/2006 (rainy season). The immatures and adults collected were identified as forensic indicators. The decomposition process presented five stages (fresh, bloated, decay, adipocere-like and skeletonization). The first four days included the first three stages of decomposition and were the most attractive to the Calliphoridae. The three taxa that were most abundant, regular and with highest peaks in the first four samples of each experiment were, in ascending order: Hemilucilia semidiaphana (Rondani), Hemilucilia segmentaria (Fabricius) e Paralucilia spp.. Linear regressions showed low values of F and high values of P, indicating that rain did not influence the sampling results. Distribuição Temporal de Moscas Varejeiras de Importância Forense (Diptera: Calliphoridae), em Porcos Domésticos, com Massa Corporal Comparável ao de um ser Humano Adulto, na Reserva Florestal Adolpho Ducke, Manaus, Amazonas, Brasil Resumo. Uma das famílias de insetos de maior importância forense é Calliphoridae (Diptera). Diferentes espécies dessa família foram utilizados para descrever a eficiência da modelagem experimental aplicada neste estudo. Porcos domésticos foram utilizados como modelos (aproximadamente 60 kg), em Manaus, Amazonas, na Reserva Floresta Adolpho Ducke. Para minimizar o efeito das coletas repetidas no mesmo modelo (consequência da pseudoreplicação), foram utilizados simultaneamente dois modelos para responder duas perguntas: 1) Qual a composição e a distribuição temporal dos califorídeos adultos? 2) Qual a composição e a distribuição temporal dos califorídeos que efetivamente colonizaram a carcaça? Foram estudadas seis pseudoréplicas em três períodos: de 30/06/2005 a 30/07/2005 (estação menos chuvosa); de 18/10/2005 a 17/11/2005 (transição entre as duas estações) e de 15/03/2006 a 14/04/2006 (estação mais chuvosa). As táxons coletados nos estágios adulto e imaturo, na carcaça, foram apontadas como indicadoras forenses. O processo de decomposição apresentou cinco estágios: fresco, inchamento, deterioração, saponificação e esqueletização.. Os primeiros quatro dias compreendem os três primeiros estágios do processo de decomposição e foram os mais atrativos para os califorídeos. Os três táxons mais abundantes, regulares e que apresentaram os maiores picos nas quatro primeiras coletas de cada experimento em ordem crescente foram, Hemilucilia semidiaphana (Rondani), Hemilucilia segmentaria (Fabricius) e Paralucilia spp.. Regressões lineares mostraram baixos valores de F e altos de P, indicando que a chuva não influenciou nos resultados das coletas.


2005 ◽  
Vol 53 (1-2) ◽  
pp. 13-21 ◽  
Author(s):  
Mauricio Camargo ◽  
Victoria Isaac

This study analyses the spatial and temporal distribution of the dominant Sciaenids in the Caeté estuary on the northern coast of Brazil. Samples were taken by otter trawls in four areas of the Caeté estuary between October 1996 and August 1997 six bimonthly. Stellifer rastrifer, Stellifer naso and Macrododon ancylodon presented the highest biomass out of eleven species of Sciaenidae caught. Minimum and mean length at first maturity were calculated and the main spawning periods determined. Changes in the spatio-temporal distribution of the three species were related to seasonal changes in estuarine salinity and spawning pulses. Larvae and juveniles of S. rastrifer, S. naso and M. ancylodon were found in the inner estuary while larger specimens were more abundant in the outer estuary with higher salinities. M. ancylodon spawned from October to February and rested from April to August whereas S. rastrifer and S. naso spawned throughout the year, though with two peaks, in October-December and June.


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