scholarly journals Long-term patterns of spatial and temporal distribution in the seabob shrimp Xiphopenaeus kroyeri (Decapoda: Penaeidae) population in southeastern Brazil

2014 ◽  
Vol 34 (3) ◽  
pp. 326-333 ◽  
Author(s):  
Gisele Salgado Heckler ◽  
Roberto Munehisa Shimizu ◽  
Adilson Fransozo ◽  
Sergio Rosso ◽  
Rogerio Caetano da Costa
Keyword(s):  
Temporal Distribution ◽  
Southeastern Brazil ◽  
Spatial And Temporal Distribution ◽  
Xiphopenaeus Kroyeri

Needs and perspectives of odour research in the aquatic sciences

2007 ◽  
Vol 55 (5) ◽  
pp. 367-369
Author(s):  
F. Jüttner
Keyword(s):  
Secondary Metabolites ◽  
Food Web ◽  
Molecular Mechanisms ◽  
Temporal Distribution ◽  
Regulatory Mechanisms ◽  
Future Research ◽  
Spatial And Temporal Distribution ◽  
The Common ◽  
Aquatic Sciences

Over more than four decades odour research in the aquatic sciences has increasingly focused on cyanobacteria and the common odour-causing compounds, geosmin and 2-methylisoborneol. Success in future research requires a long-term perspective. Key areas for investigation are secondary metabolites and cyanobacteria, regulatory mechanisms for geosmin and other compounds' synthesis; understanding their spatial and temporal distribution (particularly relating to the food web in a habitat); and molecular mechanisms for liberation of geosmin by microorganisms.

Spatial and temporal distribution of long-term short-wave surface radiation over Greece

2006 ◽  
Vol 132 (621) ◽  
pp. 2693-2718 ◽  
Author(s):  
A. Fotiadi ◽  
N. Hatzianastassiou ◽  
P. W. Stackhouse ◽  
C. Matsoukas ◽  
E. Drakakis ◽  
...  
Keyword(s):  
Temporal Distribution ◽  
Short Wave ◽  
Surface Radiation ◽  
Spatial And Temporal Distribution ◽  
Wave Surface

scholarly journals Spatial and temporal distribution of stream macroalgae in a tropical river basin

2015 ◽  
Vol 15 (4) ◽  
Author(s):  
Aurélio Fajar Tonetto ◽  
Cleto Kaveski Peres ◽  
Rafael Taminato Hirata ◽  
Ciro Cesar Zanini Branco
Keyword(s):  
Environmental Factors ◽  
Light Availability ◽  
Temporal Distribution ◽  
Southeastern Brazil ◽  
Spatial And Temporal Variation ◽  
Major Influence ◽  
Spatial And Temporal Distribution ◽  
Tropical River ◽  
Stream Macroalgae ◽  
One Year

Spatial and temporal distribution of stream macroalgae in streams from southeastern Brazil were assessed for one year. The fluctuations in macroalgal species composition and environmental factors were monitored monthly. The region exhibit a tropical climate, with defined rainy and dry seasons. Nineteen species were found, with a predominance of Chlorophyta (52.7% of the species), followed by Cyanobacteria (26.3%), Ochrophyta and Rhodophyta (10.5% each). Scytonema arcangeli had the highest number of records (63.6%), while Mougeotia capucina occurred in all sampling sites. Community structure had low similarity (20-26%) and the environmental factors showed a weak contribution to the distribution pattern observed. Despite this, the light availability at the stream-bed seems to be a major influence on the macroalgal seasonal dynamics. We suggest that macroalgae communities are predominantly composed of rare species, and this could explain the lack of a clear spatial and temporal variation pattern of these organisms.

scholarly journals Annual, seasonal and spatial abundance of the seabob shrimp Xiphopenaeus kroyeri (Decapoda, Penaeidae) off the Southeastern coast of Brazil

2014 ◽  
Vol 86 (3) ◽  
pp. 1337-1346 ◽  
Author(s):  
GISELE S. HECKLER ◽  
MATEUS LOPES ◽  
SABRINA M. SIMÕES ◽  
ROBERTO M. SHIMIZU ◽  
ROGERIO C. DA COSTA
Keyword(s):  
Grain Size ◽  
Temporal Distribution ◽  
Fine Sand ◽  
Spatial And Temporal Distribution ◽  
Sediment Grain Size ◽  
Low Salinity ◽  
Sampling Locations ◽  
Xiphopenaeus Kroyeri ◽  
Reproductive Females ◽  
Estuarine Region

We investigated the influence of environmental factors in spatial and temporal distribution of the seabob shrimp Xiphopenaeus kroyeri in Santos Bay and São Vicente Estuary, state of São Paulo, Brazil. Monthly samples were obtained, from May 2008 through April 2010, from four locations in the estuary and four in the bay. No individual was collected in the estuary and this was attributed to the low salinity means recorded in this environment. We collected 109,153 individuals in the bay and there was no difference in abundance between the two years comprised by the study period. The similarity in spatial distribution can be related to sediment grain size that in all sampling locations showed great amount of very fine sand. The largest amount of reproductive females was obtained in early 2010, when temperature was high, and this could have increased the juvenile recruitment in April 2010. According to our results, the distribution of X. kroyeri in the study area is influenced by temperature, which is related to reproduction, and salinity, limiting the entrance of individuals in the estuarine region.

scholarly journals Long Term Trends of Hydrology, Sediment Yield and Crop Productivity in Andit Tid Watershed Central Highlands of Ethiopia

2020 ◽  
Author(s):  
Ayele Desalegn ◽  
Tilahun Getachew ◽  
Temesgen Yilma ◽  
Tilashwork Chanie
Keyword(s):  
Trend Analysis ◽  
Sediment Yield ◽  
Water Conservation ◽  
Crop Production ◽  
Temporal Distribution ◽  
Sediment Concentration ◽  
Spatial And Temporal Distribution ◽  
Sediment Loss ◽  
Long Term Trends

Abstract Background: Previously in Ethiopia reliable climatic and hydro-meteorological data are not available and not maintained properly but the long-term database is needed for the assessment and planning of resource dynamics. To minimize the lack of reliable database, the Soil Conservation Research Program (SCRP) established observatory model watersheds since 1981. Andit tid watershed is one of these watersheds established for monitoring the long term trends of climatic, hydrologic, sediment loss and crop production system as a representative site for central high land parts of Ethiopia at 1982. This research paper compiles the analysis of spatial and temporal distribution of the rain fall; trends of run off and sediment loss and their relation and the influence of position of terraces on crop production. Result: From the rainfall trend analysis result the rainfall of the watershed has insignificant spatial (PCI=1.07) and temporal (CV=16.7%) variation. The precipitation coefficient (%) value of the watershed indicates that July and August have big rain with high concentration; September have big rain with moderate concentration and these three months could contribute more than one twelfth of total rainfall amount. The highest runoff and sediment yield were observed in August and July, while sediment concentration was generally high in June. All crops delivered statistically highest yield (P<0.05) immediately above bunds (zone a). Conclusion: The rainfall spatial and temporal distribution trend analysis results conclude that the watershed is not vulnerable for future drought. The highest sediment concentration occurred in June was because of the reason that the lands are plowed and prepared for crop growth; following this small rainfall can carry much soil and can contribute for high suspended sediment concentration. The highest grain yield obtained from above bunds is because of the trapped and accumulated soil and plant nutrient could contribute for better performance and production of crops. To obtain better crop yield; to minimize sediment loss and improve the stream flow it is better to maintain the existed soil and water conservation structures and apply the new interventions.

scholarly journals Abundance and spatial-temporal distribution of the shrimp Xiphopenaeus kroyeri (Decapoda: Penaeidae): an exploited species in southeast Brazil

2016 ◽  
Vol 76 (3) ◽  
pp. 764-773
Author(s):  
E. R. Silva ◽  
G. S. Sancinetti ◽  
A. Fransozo ◽  
A. Azevedo ◽  
R. C. Costa
Keyword(s):  
Species Abundance ◽  
Organic Matter Content ◽  
Coastal Region ◽  
Temporal Distribution ◽  
Mesh Size ◽  
Matter Content ◽  
Southeastern Brazil ◽  
Otter Trawl ◽  
Xiphopenaeus Kroyeri

Abstract This study evaluated the abundance and spatial-temporal distribution of the shrimp Xiphopenaeus kroyeri in the coastal region of Macaé, state of Rio de Janeiro, southeastern Brazil. Monthly samples were obtained from March 2008 to February 2010 in six stations located in Inner (5, 10 and 15m depth) and Outer (25, 35 and 45m depth) areas. It was used a commercial fishery boat equipped with an otter-trawl net (3.5 m mouth width, mesh size 20mm and 15mm in the cod end). Water samples were taken for determination of temperature and salinity, and sediment samples for determination of texture and organic matter content. A total of 7146 shrimps were sampled. About 95% of all shrimps were caught in the shallow area, i.e., depths <20m. Greatest abundances were recorded in winter and spring. No significant correlation was observed between sediment (phi) and abundance. The distribution of X. kroyeri in the studied area was closely related to seasonal cold waterfront of the South Atlantic Central Water (SACW) and temperature was the main factor affecting the species abundance.

scholarly journals Spatial and temporal distribution of foot and mouth disease outbreaks in Amhara region of Ethiopia in the period 1999 to 2016

2020 ◽  
Vol 16 (1) ◽  
Author(s):  
Endris Aman ◽  
Wassie Molla ◽  
Zeleke Gebreegizabher ◽  
Wudu Temesgen Jemberu
Keyword(s):  
Temporal Distribution ◽  
Foot And Mouth Disease ◽  
Dry Season ◽  
Mouth Disease ◽  
Spatial And Temporal Distribution ◽  
Amhara Region ◽  
Term Trend ◽  
Foot And Mouth ◽  
Long Term Trend

Abstract Background Foot and mouth disease (FMD) is an economically important trans-boundary viral disease of cloven-hoofed animals. It is caused by FMD virus, which belongs to the genus Aphthovirus and family Picornaviridae. FMD is a well-established endemic disease in Ethiopia since it was first detected in 1957. This retrospective study was carried out to identify the spatial and temporal distribution of FMD outbreaks in Amhara region of Ethiopia using 18 years (January 1999–December 2016) reported outbreak data. Results A total of 636 FMD outbreaks were reported in Amhara region of Ethiopia between 1999 and 2016 with an average and median of 35 and 13 outbreaks per year respectively. In this period, FMD was reported at least once in 58.5% of the districts (n = 79) and in all administrative zones of the region (n = 10). The average district level incidence of FMD outbreaks was 4.68 per 18 years (0.26 per district year). It recurs in a district as epidemic, on average in 5.86 years period. The incidence differed between administrative zones, being the lowest in East Gojjam and highest in North Shewa. The occurrence of FMD outbreaks was found to be seasonal with peak outbreaks in March and a low in August. The long-term trend of FMD outbreaks indicates a slight, but statistically significant (p < 0.001) decrease over the study period. Conclusion FMD occurred in all zones of the region and showed statistically significant decrease in the long-term trend. Numbers of outbreaks were relatively higher during dry season. The spatial and temporal distribution identified in this study should be considered in controlling the disease. As unregulated and frequent animal movements are the likely causes of high outbreak occurrence during the dry season, animal movement regulations should be considered for the long-term control of FMD.

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