scholarly journals Seasonal Variations of Densities of Biomphalaria pfeifferi, the Intermediate Host of Schistosoma mansoni Parasite at the North of Senegal

2021 ◽  
Author(s):  
Sidy Bakhoum ◽  
Christopher J.E. Haggerty ◽  
Cheikh Tidiane Ba ◽  
Nicolas Jouanard ◽  
Gilles Riveau ◽  
...  

Schistosomiasis is becoming more persistent because of the widespread distribution of intermediate host snails in several regions of Africa, including Senegal. The intermediate snail host of the human intestinal schistosome is Biomphalaria pfeifferi and is permanently present in northern Senegal because of the presence of the abundant freshwater habitat throughout the year. Here, we observed the seasonal variation in B. pfeifferi abundance in the Saint-louis region at the North of Senegal in West Africa. We performed snail and environmental parameter sampling across two different seasons described for Senegal: a dry season that runs roughly from mid-October to mid-June and a rainy season that spans approximately from late June to early October. We also split the dry season into two categories representing periods of time when water temperatures were either decreasing (dry1) or increasing (dry2). We used regression analyses to model snail density across the seasons and investigated which environmental variables influenced snail abundance. Results suggested that snails were more abundant and peaked during the rainy season, which lowest abundances during the dry season when temperatures were declining. The above seasonal variations of snail density were positively linked to the environmental drivers including periphyton (food resource for snails), aquatic vegetation abundance, water temperature and dissolved oxygen and negatively to both pH and water conductivity. Our findings may be useful for snail control efforts by targeting specific periods and/or site conditions when snail abundances are greatest.


2014 ◽  
Vol 1010-1012 ◽  
pp. 1059-1063
Author(s):  
Wei Guan ◽  
Tao Fan ◽  
Xiu Qin Zhu

To elucidate the relationship between stable isotopes of precipitation (SIP) and the extreme drought in Kunming area, based on the stable isotopes data of the GNIP in Kunming site from 1986 to 2003, the precipitation line equation is brought forward and the seasonal change rule of stable isotopes are discussed. The stable isotopic compositions of precipitation exhibit great diversities in different seasons during to influences of multiple factors, such as monsoon, rainfall amount moisture source and others. The δ18O values in rainwater exhibit significant seasonal variations, the average of-10.12‰ in rainy season, the dry season is-4.5‰, having lower values in the rainy season and higher one in the dry season. The amount effect of precipitation is very distinct, that concealed the temperature effect. Got the special geographical position,dvalues present unique characteristics, the average ofdvalues is 10.78‰ in rainy season, and is 4.86‰ in dry season, the mean value is generally lower than most parts of the world.



2019 ◽  
Vol 4 (2) ◽  
Author(s):  
Vine Valenia David ◽  
Kancitra Pharmawati ◽  
Djoni Kusmulyana Usman

<p>Clean water crisis that occurred in Bandung is caused by land conversion in North Bandung area which is a recharge area into commercial buildings. This increases runoff rate from 40% to 70% that can lead can lead to flooding and reduced groundwater availability. Therefore, it is necessary to save water by implementing water conservation. Considering those problems, this study aims to apply the concept of water conservation in X Apartment building that is located in the North Bandung Region by referring to Mayor Regulation of Bandung in 2016. Water conservation efforts that will be applied are wastewater reuse into water recycle, rainwater harvesting, infiltration well construction and placing water meters. The application of water conservation concept considers two conditions, namely in rainy season and dry season. Total need for clean water can be saved by 45,8% in dry season, while in rainy season clean water can be saved by 31,74%.</p>



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 2 (3) ◽  
Author(s):  
Ade Arinda ◽  
Eka Wardhani

 ABSTRAKAir Waduk Saguling saat ini menunjukkan penurunan, baik secara kualitas maupun kuantitas akibat aktivitas manusia yang menghasilkan limbah rumah tangga, industri, pertanian, peternakan, perikanan dan pertambangan. Salah satu pencemar di Waduk Saguling adalah logam berat. Penelitian ini bertujuan menganalisis konsentrasi Pb di perairan Waduk Saguling pada musim yang berbeda. Penelitian ini menggunakan data sekunder yang diperoleh dari PT Indonesia Power tahun 2008-2017. Data berasal dari tiga kedalaman yaitu kedalaman permukaan, tengah, dan dekat dasar perairan. Berdasarkan hasil penelitian menunjukkan konsentrasi Pb di musim kemarau lebih tinggi daripada musim hujan dan sebagian sudah melebihi baku mutu yang mengacu pada Peraturan Pemerintah No. 82 Tahun 2001 tentang Pengelolaan Kualitas Air dan Pengendalian Pencemaran Air untuk logam Pb sebesar 0,03 mg/L. Parameter pendukung yang di analisis yaitu parameter DO, pH, TDS, suhu, kekeruhan, dan kesadahan. Berdasarkan hasil analisis statistik menggunakan PCA, parameter yang paling mempengaruhi konsentrasi Pb di musim kemarau adalah kekeruhan dan suhu sedangkan musim hujan adalah TDS.Kata kunci: Musim, Pb, PCA, Waduk SagulingABSTRACTSaguling Water Reservoir currently shows a decline, both in quality and quantity due to human activities that produce domestic waste, industry, agriculture, livestock, fishery and mining. One of the pollutants in Saguling Reservoir is heavy metal. The research aims to analyze the concentration of Pb in the waters of Saguling Reservoir in different seasons. This research uses secondary data which is obtained from PT Indonesia Power in 2008-2017. The data comes from three depths: surface depth, center, and near bottom of water. Based on the results of the research shows that the concentration of Pb in the dry season is higher than the rainy season and some have exceeded the quality standard which refers to Government Regulation no. 82 of 2001 on the Management of Water Quality and Control of Water Pollution for Pb metal by 0.03 mg/L. The supporting parameters in the analysis are DO, pH, TDS, temperature, turbidity, and hardness parameters. Based on the results of statistical analysis using PCA, the parameters that most influence the concentration of Pb heavy metals in the dry season are turbidity and temperature and rainy season is TDS.Keywords: Season, pb, pca, saguling reservoi



1981 ◽  
Vol 32 (3) ◽  
pp. 321 ◽  
Author(s):  
E Wolanski ◽  
M Jones ◽  
WT Williams

The distribution of salinity, temperature, suspended particles, light transmissivity, chlorophyll a and phaeopigments across the Great Barrier Reef lagoon offshore Townsville, was measured from 9 January 1979 to 23 January 1980 at approximately weekly intervals. Previous observations at Low Isles. 400 km to the north, on seasonal variations of temperature and salinity were generally applicable here. A shallow summer thermocline was frequently observed in offshore waters, in the dry season and in calm weather. As a result of evaporation from the lagoon and adjoining mangrove swamps during the dry season, an inverse estuarine circulation can exist when high salinity, sediment-rich, nearshore waters sink below the less saline offshore waters. Only nearshore were bottom sediments strongly entrained in the water column during strong winds, principally in winter.



2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Rong Lu ◽  
Kenichiro Anzai ◽  
Bach Trong Phuc ◽  
Tetsuo Miyakoshi

Vietnamese lacquers collected every month from June to March of next year were characterized. Composition analysis showed that lacquer collected in rainy season contained much water, while those collected in dry season contained more lipid component. Although hardness of lacquer films is not very hard, lacquers tapped in all seasons can reach hard dry (HD) within 48 hours. Refining lacquer can accelerate drying time but the water concentration should be maintained around 10 wt% for laccase activity.



Agrologia ◽  
2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Zakarias Frans Mores Hukom

Antioxidant is a term related to the activity ability and properties of the active ingredient.  The higher the ability of the antioxidant activity of an active ingredient, the stronger its antioxidant properties are to ward off various free radical compounds due to oxidative stress. The activity ability and antioxidant properties of tea shoots often fluctuate with changing seasons.  This study investigated the effect giving nitrogen levels in organic + inorganic liquid fertilizers on the ability of activity and antioxidant properties of tea shoots in different seasons. The experimental design used was a over season complete randomized block design consisting of 5 levels of fertilization concentration in the rainy and dry seasons. The results showed that the application of organic + inorganic liquid fertilizers without the addition of N concentration in the dry season had a significant effect on the antioxidant activity of tea shoots by 88.14%, and 34.15% higher than control plants in the rainy season and 41.81% more. Height of control plants in the dry season. The IC50 value of tea shoots in the rainy season and dry season has very strong antioxidant properties where the order of the antioxidant properties of the control plants < all concentrations of adding N to organic + inorganic liquid fertilizers < concentration of organic + inorganic liquid fertilizers without the addition of N.Keywords: Ability Antioxidant Activity, Organic + Inorganic Liquid Fertilizer, Tea shoots, Antioxidant Properties.



2017 ◽  
Vol 98 (5) ◽  
pp. 1151-1157 ◽  
Author(s):  
R.C. De Carli ◽  
F.J.L. Silva ◽  
J.M. Silva

Activities displayed by animals are usually cyclic, and fluctuations in behavioural repertoires can be observed on a daily or seasonal timescale. The present study describes daily and seasonal variations in the aerial events – such as leaps, spins and slaps with body parts – by spinner dolphins in Baía dos Golfinhos, Fernando de Noronha Marine National Park, in Brazil. To measure aerial events by dolphins, we compiled and analysed data collected from January 2006 to December 2010. A total of 113,027 aerial events were recorded during 1431 days of land-based daytime observations. Our results show that the frequency of aerial events was positively correlated with the number of dolphins in the bay. The relative frequency of aerial events was higher in the rainy season, when compared with the dry season. Aerial activities also varied throughout the day, with dolphins being more active in the morning, specifically from 8:00 a.m. to 8:59 a.m., regardless of the season.



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.



2021 ◽  
Vol 35 (2) ◽  
pp. 186-194
Author(s):  
R. A. Sobayo ◽  
E. B. Oguntona ◽  
O. A. Osinowo ◽  
D. Eruvbetine ◽  
A. M. Bamgbose ◽  
...  

Two studies were conducted to evaluate the nutritional effects of supplementary ascorbic acid (AA) at levels of 0, 100, 200, and 300 mg/kg in the diets of growing pullets reared at different seasons (dry season and rainy season).240 eight weeks-old Harco pullet chicks were used in each trial, they were randomly assigned to each of the four dietary treatments in three replications of twenty chicks per replicate. Each trial lasted 12 weeks (84 days) during which data were collected and a 2 X 4 factorial arrangement was employed in the analysis of data collected. Both ascorbic acid and season significantly affected (P<0.05) growth rate with better growth rate reported in the dry season. Body weights at first lay exhibited a linear reduction with increasing concentration of ascorbic acid (P<0.05). Seasonal variation significantly affected (P<0.05) age and egg weight at first lay with higher values obtained in the rainy season. The cost-benefit analysis of supplementary ascorbic acid in the diet of experimental birds revealed that inclusion of the graded levels of ascorbic acid increased the cost of feed in a linear fashion across the dietary treatments. At the growing stage, cost of feed per kg weight gain was found to be lowest in birds fed 0 mg/kg AA. It was evident that at the growing stage, optimum response occurred with supplementation of 300 mg/kg AA.



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