scholarly journals Factors Influencing Seasonal and Daily Dynamics of the Genus Stomoxys Geoffroy, 1762 (Diptera: Muscidae), in the Adamawa Plateau, Cameroon

2019 ◽  
Vol 2019 ◽  
pp. 1-9 ◽  
Author(s):  
Sevidzem S. Lendzele ◽  
Mavoungou J. François ◽  
Zinga-Koumba C. Roland ◽  
Koumba A. Armel ◽  
Gérard Duvallet

The rangelands of the Vina Division on the Adamawa Plateau are densely infested with Stomoxyinae, but little is known about their species composition and ecology. A trap-transect survey was carried out in three villages: Galim, Mbidjoro, and Velambai, using Nzi (n = 3), Vavoua (n = 3), and Biconical (n = 3) traps, all baited with octenol. Three traps of each trap type were set in each of the study villages, and collections were carried out daily. In total, 3,762 Stomoxys spp. were collected from October 2016 to June 2017 and identified using standard keys into five species: Stomoxys niger niger, S. calcitrans, S. niger bilineatus, S. omega, and S. xanthomelas. Galim recorded the highest apparent density of stomoxyines (30 stomoxyines/trap/day) with a statistically significant difference (p<0.05). The Vavoua trap was an ideal tool for Stomoxyinae collection. Stomoxyines abundantly occurred at the end of the dry season (March 2017) and beginning of the rainy season (May 2017). The monthly rainfall positively influenced monthly ADTs of Stomoxyinae. Their diurnal biting activity was bimodal in the rainy season and unimodal in the dry season. The daily activity peak was between 14 h and 16 h with a mean temperature of 31°C, a mean wind speed of 1.5 m/s, and a mean humidity of 50%. The daily trap catch was positively influenced by temperature and wind speed but negatively influenced by rainfall and air humidity. Weather variables influenced Stomoxys spp. monthly and daily ADTs.

2010 ◽  
Vol 60 (2) ◽  
pp. 123-131 ◽  
Author(s):  
Ashenafi Hagos ◽  
Hailu Yacob ◽  
Asoke Basu ◽  
Degneh Efrem

AbstractA study on the epidemiology of bovine trypanosomosis was conducted from September 2006 to April 2007 in six villages of the Gimbi district in west Wollega zone of Ethiopia. The prevalence of the disease, the apparent densities and distribution of tsetse and other biting flies in two seasons, the dry and rainy, were determined. The results of a questionnaire survey from 80 farmers revealed that trypanosomosis was a major health problem affecting animals and impeding agricultural activities.A total of 568 blood samples were collected from randomly selected animals (280 animals in rainy and 288 in dry season) and revealed the presence of Trypanosoma congolense Broden, 1904 and T. vivax Zieman, 1905 in the area. Trypanosoma congolense was the dominant species that accounted for 66.2% of the infections. The mean packed cell volume (PCV) concentrations were 22.77% (95% CI =19.99-21.55) in parasitaemic and 25.25% (95% CI=24.88-25.61) in aparasitaemic animals with a significant difference (P<0.005). There was a significant (P<0.012) difference in trypanosome infection between age groups of cattle, being higher in adults. The overall prevalence of trypanosomosis was 12.5%, while the disease prevalence was higher during the rainy season (15 %) than the dry season (10.1%). In three villages of lowland areas (below 1600 meter above sea level), a higher prevalence was recorded 20.9% and 7.9% as compared to three villages of midland areas (≥ 1600 meter above sea level) 11.8% and 8.3% in late rainy and dry season, respectively.A fly-survey was conducted by using 80 monoconical pyramidal traps and revealed that two tsetse species, namely Glossina morsitans submorsitans Newstead and Glossina tachinoides Westwood were found along with other biting flies (Tabanus, Haematopota and Stomoxys species). Higher numerical catches of Glossina were recorded in late rainy season and the apparent density was positively correlated (r=0.5171) with the prevalence of infection.


2018 ◽  
Vol 35 ◽  
pp. 1-12
Author(s):  
Cynthia Diniz Souza ◽  
Vandick S. Batista ◽  
Nidia Noemi Fabré

Seasonal ecological effects caused by temperature and photoperiod are typically considered minimal in the tropics. Nevertheless, annual climate cycles may still influence the distribution and abundance of tropical species. Here, we investigate whether seasonal patterns of precipitation and wind speed influence the structure of coastal fish assemblages and fishing yields in northeast Brazil. Research trips were conducted during the rainy and dry seasons using commercial boats and gear to sample the fish community. Diversity was analyzed using abundance Whittaker curves, diversity profiles and the Shannon index. Principal Component Analysis (PCA) was used to analyze associations between the abundance of species and various environmental variables related to seasonality. A total of 2,373 fish were collected, representing 73 species from 34 families – 20 of which were classified as both frequent and abundant. Species richness was greater and more equitable during the rainy season than the dry season – driven by changes in the precipitation rather than to wind speed. Species diversity profiles were slightly greater during the rainy season than the dry season, but this difference was not statistically significant. Using PCA was identified three groups of species: the first associated with wind speed, the second with precipitation, and the third with a wide range of sampling environments. This latter group was the largest and most ecologically heterogeneous. We conclude that tropical coastal fish assemblages are largely influenced by local variables, and seasonally mediated by annual changes related to precipitation intensity and wind speed, which in turn influences fishery yields.


Jurnal MIPA ◽  
2014 ◽  
Vol 3 (1) ◽  
pp. 58 ◽  
Author(s):  
Farid Mufti ◽  
As'ari .

Penelitian ini mengkaji lebih dalam kondisi angin dan kelembapan udara pada saat musim hujan dan musim kemarau di Manado dengan menggunakan data di lapisan permukaan dan data udara atas dari Stasiun Meteorologi Sam Ratulangi Manado. Tujuan utama dari penelitian ini adalah mendapatkan hubungan antara kondisi angin dan kelembapan lapisan atas terhadap lapisan permukaan, sehingga dapat memprakirakan kondisi angin dan kelembapan lapisan permukaan dengan berdasarkan keadaan lapisan atas. Metode yang digunakan adalah mengkomponenkan angin dalam arah utara-selatan dan timur-barat, selanjutnya mencari keterkaitan dengan menggunakan teknik korelasi. Hasil penelitian ini menunjukkan pada saat musim hujan angin pada lapisan 1500 m dan angin di lapisan permukaan memiliki arah yang sama dan saling menguatkan untuk komponen timur-barat (zonal) dengan koefisien korelasi r=0,56, sedangkan pada saat musim kemarau angin pada lapisan 1500 m dan angin di lapisan permukaan memiliki arah yang sama dan saling menguatkan untuk komponen utara-selatan (meridional) dengan koefisien korelasi r=0,45. Keterkaitan yang cukup kuat antara angin dengan kelembapan terjadi pada komponen V (meridional) yaitu, pada saat musim hujan, semakin besar kecepatan angin komponen negatif (utara) semakin besar pula kelembapan udara di lapisan permukaan, dengan koefisien korelasi benilai positif r=0.40. Pada saat musim kemarau, semakin besar kecepatan angin komponen positif (selatan) semakin kecil kelembapan udara di lapisan permukaan, dengan koefisien korelasi bernilai negatif r=— 0,48.This study examined the wind and humidity condition in the rainy season and dry season in Manado by using the data in surface layer and upper air data from the Sam Ratulangi Meteorological Station. The primary objective of this study was to find the relationship between wind condition and upper layer humidity to surface layer, using correlation technique, in order to predict wind condition and humidity of the surface layer based on the condition of the upper layer. The results showed that, during the rainy season, the wind at layer 1500 m and surface layer had the same direction and mutually reinforced for the east-west component (zonal) with correlation coefficient r=0.56, whereas during the dry season, wind at layer 1500 m and at surface layer had the same direction and mutually reinforced for the north-south component (meridional) with correlation coefficient r=0.45. A relationship between wind and humidity was found at V component (meridional), which was, at rainy season, the higher the wind speed of negative component (north) the higher the humidity at surface layer with positive correlation coefficient r=0.40. At dry season, the higher the wind speed of positive component (south), the lower the humidity at the surface layer, with negative correlation coefficient r=—0.48.


2018 ◽  
Vol 1 (2) ◽  
pp. 96
Author(s):  
Hermawan Hermawan

Microclimate variables are one of the variables that affect adaptive thermal comfort. The microclimate variables are air temperature, solar radiation temperature, air humidity and wind speed. In this study the discussion of microclimate variables is specific to air temperature and air humidity. This is based on other studies which mention that the most influential climate variables are air temperature and humidity. This research is a field study that will compare air temperature and humidity in coastal and mountain areas. Measurements are carried out in 3 seasons, namely the dry season to rain, the rainy season and the rainy season to the dry season. Measurement of air and humidity temperature variables in two rooms in the building and outside space and terrace. The results of the study show that there are significant differences between coastal and mountain dwellings. This difference is related to adaptive thermal comfort through thermal sensation. Thermal sensation results show that the location of the mountain is that most residents feel cool, while at the beach location, the residents are mostly comfortable or neutral.


2021 ◽  
Vol 015 (02) ◽  
pp. 049-058
Author(s):  
Samuel Olorunyomi Oninla ◽  
Michael Olaniyan Onigbinde ◽  
Akinyemi Olaleye Fadugbagbe ◽  
Emmanuel Olaseinde Bello ◽  
Omolayo Adebukola Olubosede

Objective: This study set out to assess sex differences and seasonal variations in Pediatric Infectious Diseases (PID) admissions. Methods: One year retrospective study of PID admissions was conducted among children aged one month to 15 years. Relevant information retrieved from patients’ hospital records were dates of admission and discharge, age, sex, final PID diagnoses and outcome. Results: Of 1,035 patients’ records assessed, 603 (58.3%) were males and 432 (41.7%) females (p<0.001). Males in ages 1-12 and 13-59 months contributed largely to the gender difference. Over the 12 months period, PID admissions mean was 86.25±21.92, with rainy and dry seasons means of 92.57±20.7 and 77.4±20.9, respectively (p<0.001). Ages 13-19, 60-119 and ≥120 months had significantly higher admissions mean during the rainy season (p<0.001 in each group), while higher admissions occurred among ages 1-12months in dry season (p<0.001). Top six PID managed were malaria, gastroenteritis, pneumonia, septicemia, meningitis and typhoid, and males had higher incidence in all except for typhoid, with only malaria having significant difference (p<0.001). Malaria, septicemia and typhoid incidence were higher significantly during the rainy season, while gastroenteritis occurred more in the dry season. Overall fatality rate was 4.6%; females and males rates were 6.3% and 3.5%, respectively (p=0.661). Rainy and dry seasons mortality means were 5±1.77 and 2.6±0.8, respectively (p<0.001). Conclusion: Male children were more vulnerable to PID, with significant higher malaria incidence among them than females. PID incidence and mortality were significantly higher during the rainy season than dry. Malaria and gastroenteritis occurred significantly in rainy and dry seasons, respectively.


2020 ◽  
Vol 4 (3) ◽  
pp. 446-452
Author(s):  
Michael Ohakwere-Eze ◽  
A. A. Udo ◽  
C. V. Nosike ◽  
A. Alhassan ◽  
M. K. Adamu

The sources of energy we use in our day-day activities contributes significantly to the alarming global warming which the world is currently experiencing. A technical solution to the menace of an environmental friendly, sustainable and reliable energy is the peak of this research. Wind speed data from 2014 to 2017 measured at a height of 2 m were analyzed using the Weibull’s distribution method. The results show that all through the studied years and seasons, the mean wind speed distribution for the rainy season is significantly stable as seen from the K-values. However, the dry season has the highest K-value of 2.08 signifying more stable winds during the season. The monthly averages, computed for height of 60 m above ground level ranges between 2.15 m/s and 6.42 m/s with the maximum wind speed in June while the minimum wind speed occurred in September. This implies that the wind velocity of the study area tends to be lower during the end of the rainy season. Nevertheless, the deviation in the mean wind speed was not significant, as such wind energy can serve as a reliable energy source for the area hence could be harvested


2018 ◽  
Vol 35 ◽  
pp. 1-12 ◽  
Author(s):  
Cynthia Diniz Souza ◽  
Vandick S. Batista ◽  
Nidia Noemi Fabré

Seasonal ecological effects caused by temperature and photoperiod are typically considered minimal in the tropics. Nevertheless, annual climate cycles may still influence the distribution and abundance of tropical species. Here, we investigate whether seasonal patterns of precipitation and wind speed influence the structure of coastal fish assemblages and fishing yields in northeast Brazil. Research trips were conducted during the rainy and dry seasons using commercial boats and gear to sample the fish community. Diversity was analyzed using abundance Whittaker curves, diversity profiles and the Shannon index. Principal Component Analysis (PCA) was used to analyze associations between the abundance of species and various environmental variables related to seasonality. A total of 2,373 fish were collected, representing 73 species from 34 families – 20 of which were classified as both frequent and abundant. Species richness was greater and more equitable during the rainy season than the dry season – driven by changes in the precipitation rather than to wind speed. Species diversity profiles were slightly greater during the rainy season than the dry season, but this difference was not statistically significant. Using PCA was identified three groups of species: the first associated with wind speed, the second with precipitation, and the third with a wide range of sampling environments. This latter group was the largest and most ecologically heterogeneous. We conclude that tropical coastal fish assemblages are largely influenced by local variables, and seasonally mediated by annual changes related to precipitation intensity and wind speed, which in turn influences fishery yields.


Revista CERES ◽  
2018 ◽  
Vol 65 (3) ◽  
pp. 286-290 ◽  
Author(s):  
Jovilma Maria Soares de Medeiros ◽  
Penha Patrícia Cabral Ribeiro ◽  
Erika Paula Silva Freitas ◽  
Jéssica Anarellis Barbosa dos Santos ◽  
Karla Suzanne Florentino da Silva Chaves Damasceno

ABSTRACT Cnidoscolus phyllacanthus, popularly known as favela or faveleira, is a species of the caatinga vegetation highly resistant to drought, with high nutritional content, and having several uses. The objective of this work was to evaluate the influence of different seasons on the chemical composition of faveleira seeds in the region of Seridó/RN. The seeds collected in different seasons were separated into 3 lots (lot 1 - rainy season; lot 2 - initial dry season; lot 3 - prolonged dry season), ground, and analyzed for moisture, ash, lipids, protein, and carbohydrates. The chemical analysis the seeds showed predominance of lipids and proteins. The results showed that moisture was significant different (p < 0.05) between all the lots; the ash content in lot 1 was significantly (p < 0.05) lower (4.67 ± 0.18) than lot 3 (4.96 ± 0.08); and protein content was highest in lot 3 (30.42 ± 1.63) and significantly (p < 0.05) different from the others. There was a significant difference (p < 0.05) for lipids between the lots, with lot 2 showing the lowest content (21.57 ± 0.37). Significant difference (p < 0.05) was also found for carbohydrates between the lots, with lot 1 (14.37 ± 1.83) having the lowest content and lot 2 (39.17 ± 0.52) the highest content. The differences observed between the lots are attributed to the harvest of the seeds in different seasonal periods. The results show that the seasonal period influences the nutritional value of faveleira seeds, and that better forms of use need to be identified according to the period of harvesting.


1998 ◽  
Vol 131 (1) ◽  
pp. 31-38 ◽  
Author(s):  
A. BULDGEN ◽  
J. FRANÇOIS

Guinea grass (Andropogon gayanus Kunth cv. Bisquamulatus) and Buffel grass (Cenchrus ciliaris L. cv. Biloela) are grown as temporary fodder crops in the Sahelo-Sudanese region of Africa. Differences in their responses to drought conditions may be important in optimizing cattle feeding programmes in integrated farming systems. An experiment conducted in a wind tunnel equipped with a tank forming a weighable lysimeter compared net photosynthesis (A), stomatal conductance (gs) and leaf water potential (Ψ leaf) of both species in a mixed sward during three simulated environmental conditions: (1) rainy season, (2) drought period within the rainy season and (3) dry season.With a soil water reserve (SWR in % volume) of 8% during the drought period and the dry season, the Ψ leaf and A parameters were significantly lower (P<0·001) when compared to those recorded with a SWR of 32% in the rainy season. Mean gs values were significantly different during each environmental condition (P<0·001). No significant difference (P>0·05) was found in gs and A between the two species during the rainy and the dry season or during a diurnal cycle, although a significant difference (P<0·05) in Ψ leaf existed between the species during the dry season. During this season, Guinea grass was dormant while Buffel grass was growing slowly.When the drought period was imposed during the rainy season (SWR declined from 25 to 5%), A was reduced from 19·8 to 7·7 μmol m−2 s−1 for Guinea grass and from 16·8 to 3·7 for Buffel grass. Ψ leaf in both species dropped below −2 MPa while gs declined slowly from 0·70–0·80 to 0·55–0·60 cm s−1. A was significantly higher (P<0·05) in Guinea grass during the last days of the drying cycle, but declined rapidly when drought was extended up to the wilting point. Two days after rewatering, all the parameters of both plants were restored to previous levels.It is concluded that Guinea grass was as drought-resistant as Buffel grass and that no competition for water existed between the species in the mixed sward. The study also gives relationships between the physiological parameters of both species and the soil water content during a drying cycle.


1998 ◽  
Vol 107 (5) ◽  
pp. 406-410 ◽  
Author(s):  
Dang Hoang Son ◽  
Le Tri ◽  
Vu Manh Tien ◽  
Tran kim Phuong ◽  
Viggo Balle ◽  
...  

Few reliable data exist on the prevalence of secretory otitis media (SOM) in the Third World. A large epidemiologic cross-sectional study was undertaken in two communes in southern Vietnam to study an urban and a rural community during two different climatic conditions: the dry and rainy seasons. The participants included 3,300 children (6,598 ears) ages 6 months to 10 years. Otolaryngological and medical histories were obtained, and an otolaryngological examination was carried out on 1,669 children in April 1995 (the dry season) and on 1,631 children in December 1995 (the rainy season). Tympanograms were obtained (n = 6,055), 429 of which were type B curves. The overall prevalence of SOM was 7.1%, the highest incidence was at the age of 2 years (with a prevalence of 22%), and there was a significantly higher prevalence of SOM during the rainy season than during the dry season. No significant difference in incidence was found in the urban district as compared to the rural district.


Sign in / Sign up

Export Citation Format

Share Document