scholarly journals Phytoplankton nyctemeral variation at a tropical river estuary (Itamaracá - Pernambuco - Brazil)

2004 ◽  
Vol 64 (1) ◽  
pp. 81-94 ◽  
Author(s):  
S. R. Lacerda ◽  
M. L. Koening ◽  
S. Neumann-Leitão ◽  
M. J. Flores-Montes
Keyword(s):  
Rainy Season ◽  
River Estuary ◽  
Mesh Size ◽  
Dry Season ◽  
Tropical River ◽  
Cylindrotheca Closterium ◽  
The North ◽  
Marine Influence ◽  
Dry Seasons ◽  
Made In

The Botafogo estuary is of socio-economical importance for Pernambuco State. It is located at the north of Santa Cruz Channel, Itamaracá, Pernambuco, Brazil (07º42'50"S and 34º52'10"W). There is a critical need to understand its functioning because of the rate at which this area is being converted to land uses. The phytoplankton dynamics was studied to enhance the knowledge of and verify the possible changes which have occurred in this ecosystem. Sampling was carried out with a plankton net 65 micrometers mesh size for qualitative data, and a Van Dorn bottle for quantitative data. Concurrent hydrological and chlorophyll-a data were collected. Samplings were made in one fixed station in July 1996 (rainy season) and December 1996 (dry season), at 3-hour intervals during 24 hours. Eighty-seven specific and infra-specific taxa were identified from net plankton samples. Diatoms were most frequent, mainly Coscinodiscus centralis and Odontella regia in the rainy and dry seasons, respectively. Phytoplankton density varied from 205,000 to 1,210,000 cell.L-1 in the dry season, and from 230,000 to 2,510,000 cell.L-1 in the rainy season, indicating eutrophic conditions. Most numerically abundant were the diatoms Cyclotella meneghiniana and Cylindrotheca closterium and the phytoflagellates. The ecosystem is polluted, and deleterious effects are minimized by the marine influence which allows periodic water renewal.

scholarly journals Implementasi Konsep Konservasi Air di Gedung Apartemen X

2019 ◽  
Vol 4 (2) ◽  
Author(s):  
Vine Valenia David ◽  
Kancitra Pharmawati ◽  
Djoni Kusmulyana Usman
Keyword(s):  
Water Conservation ◽  
Rainy Season ◽  
Rainwater Harvesting ◽  
Wastewater Reuse ◽  
Dry Season ◽  
Clean Water ◽  
Groundwater Availability ◽  
The North ◽  
Water Recycle ◽  
Runoff Rate

<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>

scholarly journals Pengaruh Angin Dan Kelembapan Atmosfer Lapisan Atas Terhadap Lapisan Permukaan Di Manado

Jurnal MIPA ◽  
2014 ◽  
Vol 3 (1) ◽  
pp. 58 ◽  
Author(s):  
Farid Mufti ◽  
As'ari .
Keyword(s):  
Surface Layer ◽  
Wind Speed ◽  
Correlation Coefficient ◽  
Rainy Season ◽  
Primary Objective ◽  
Dry Season ◽  
Correlation Technique ◽  
Wind Condition ◽  
The North ◽  
Positive Correlation Coefficient

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.

scholarly journals The invertebrate colonization during decomposition of Eichhornia azurea kunth in a lateral lake in the mouth zone of Paranapanema River into Jurumirim Reservoir (São Paulo, Brazil)

2002 ◽  
Vol 62 (2) ◽  
pp. 293-310 ◽  
Author(s):  
N. de L. STRIPARI ◽  
R. HENRY
Keyword(s):  
Decomposition Rate ◽  
Rainy Season ◽  
Dry Season ◽  
Material Loss ◽  
Litter Bags ◽  
Eichhornia Azurea ◽  
Mouth Zone ◽  
Dry Seasons ◽  
Invertebrate Colonization

The invertebrate colonization during decomposition of Eichhornia azurea was observed in a lateral lake in the mouth zone of Paranapanema River into Jurumirim Reservoir in two periods of the year. The litter bags method was used for measuring the decomposition rate as well as to evaluate the invertebrates colonization. Forty-two litter bags, measuring 15 × 20 cm in size and 2 mm mesh net, were incubated "in situ". Six litter bags (three for colonization and three for decomposition measurements) were removed after the 1st, 3rd, 7th, 14th, 28th, 56th and 72nd days of incubation. After each day, the material was carefully cleaned for detritus removal and invertebrate sampling. The biological material was fixed with 4% formaline and then sorted and identified. The remaining plant material was dried in an oven (at 60ºC) and weighed. A fast material loss occurred during the first 24 hours and the decomposition rate was higher during the rainy season than in the dry season. A peak on invertebrate density (110 ind.g.DW--1) on the remaining detritus of Eichhornia azurea was recorded in the 56th day of dry season, when the polyphenol concentration of plant detritus was 0.57 UDO.g.DW--1. In the rainy season, higher density was found in the 28th day of incubation, when the polyphenol concentration was 4.36 UDO.g.DW--1. Apparently, the reduction in the polyphenol concentration was followed by an increase in invertebrate densities. The majority of the species observed in the detritus belongs to the collector group that was dominant after the 7th and 14th days in the rainy and dry seasons, respectively.

Occurrence of the grasshopper pest Zonocerus variegatus (L.) (Orthoptera: Pyrgomorphidae) in south-western Nigeria in relation to the wet and dry seasons

1980 ◽  
Vol 70 (4) ◽  
pp. 621-633 ◽  
Author(s):  
W. W. Page
Keyword(s):  
Dry Season ◽  
Seasonal Abundance ◽  
Secondary Peak ◽  
Rapid Decline ◽  
Arid Zones ◽  
Zonocerus Variegatus ◽  
Wet Season ◽  
The North ◽  
Dry Seasons ◽  
Peak Abundance

AbstractAn investigation into the seasonal abundance of Zonocerus variegatus (L.) around Ibadan, Nigeria, showed that hatching occurs between October and March and peak abundance is in late November. Adults occur almost throughout the year. Oviposition takes place between March and October or possibly November, with a peak in April. Eggs laid in March and April hatch in October and November after a diapause, while those laid from June onwards do not appear to enter diapause. Thus eggs laid in June and July hatch at the same time as those laid in March and April. Parasitism by the sargophagid fly Blaesoxipha filipjevi (Rod.) during March and April results in a rapid decline in adult numbers which may be followed by a secondary peak in adult numbers when nymphs, which are present at the same time and are rarely parasitised, reach adult stage. Oviposition resulting from such a peak does not produce a secondary peak in hatching as this coincides with hatching from earlier layings. The fungus Entomophthora grylli plays an important role in controlling the abundance of nymphs and adults during the dry season despite the intermittent nature of the attacks. During the wet season, the fungus is able to germinate and disperse more readily, thus keeping the numbers of the insects low. It is concluded that there is one generation of Z. variegatus a year, with a peak in population coinciding with the dry season (November-March). It is suggested from the results that the grasshopper may have originated in the semi-arid zones of the north.

scholarly journals Seasonal morphological variability in an in situ Cyanobacteria monoculture: example from a persistent Cylindrospermopsis bloom in Lake Catemaco, Veracruz, Mexico

2016 ◽  
Vol 75 (s1) ◽  
Author(s):  
Owen Lind ◽  
Laura Dávalos-Lind ◽  
Carlos López ◽  
Martin López ◽  
Juli Dyble Bressie
Keyword(s):  
Rainy Season ◽  
Morphological Variability ◽  
Morphological Diversity ◽  
Dry Season ◽  
Transient Condition ◽  
Dry Seasons ◽  
Trichome Morphology ◽  
Determining Factor

<p>The phrase <em>cyanobacteria bloom</em> implies a transient condition in which one to few species dominates communities. In this paper we describe a condition in which the <em>bloom</em> is of multi-year duration consisting of different morphologies of a single cyanobacteria species. Lake Catemaco, Veracruz, México maintained a year-round massive (10<sup>8</sup> trichomes L<sup>-1</sup>) population of potentially toxin-producing cyanobacteria, <em>Cylindrospermopsis spp.</em> The trichomes are present as straight and coiled morphotypes.  The relative trichome morphology abundance varied with rainy (June – October) and dry seasons (November – May), but total trichome abundance did not vary.  Coiled trichomes and heterocytes (occurring only on coiled trichomes) were significantly more abundant, both absolutely and relatively, during the dry season. Both coiled trichome and heterocyte mean volumes were significantly smaller during the rainy season than during the dry season.  Biovolumes were largest in January when water temperature was 5º C cooler suggesting buoyancy as a morphology-determining factor. However, with a more than three-fold lower TIN concentration during the dry season, we hypothesized that the coiled morphotype became abundant primarily because it formed heterocytes, which the straight morphotype did not. Spatial trichome and heterocyte abundance differences were small among the 15 lake sites (average CV for all dates = 20%). However, there was a pattern of increased heterocyte and coiled trichome abundance from lake inflow, as a nitrogen source, to outflow during the rainy season. The total volume of heterocytes per litre of lake water increased progressively four-fold from a minimum early in the rainy season to a maximum at the end of the dry season. Morphological diversity, as seen in Lake Catemaco, can partially compensate for the lack of species diversity in determination of community structure.</p>

scholarly journals Total mercury in the fish Trichiurus lepturus from a tropical estuary in relation to length, weight, and season

2011 ◽  
Vol 9 (1) ◽  
pp. 183-190 ◽  
Author(s):  
Scheyla C. T Barbosa ◽  
Monica F Costa ◽  
Mário Barletta ◽  
David Valença Dantas ◽  
Helena A Kehrig ◽  
...  
Keyword(s):  
Rainy Season ◽  
Total Mercury ◽  
River Estuary ◽  
Human Consumption ◽  
Significant Relation ◽  
Tropical Regions ◽  
Trichiurus Lepturus ◽  
Significant Difference ◽  
Dry Seasons ◽  
Rich Fauna

The Goiana River Estuary (7º30'S 34º47'W) is a typical estuary of the semi-arid tropical regions. This estuary shelters a rich fauna of fish, crustaceans and mollusks which play an important role in the life of traditional populations. It is also the main recipient of the effluents from the sugarcane agro-industry and sewage from settlements and villages. Trichiurus lepturus (n = 104), from the Goiana Estuary were examined for total mercury contents during ten months (2005 to 2007) spaning two dry seasons and part of a rainy season. The studied individuals showed weight (W) (204.1±97.9 g) and total length (TL) (63.1±10.1 cm, range 29.5-89.0 cm) with a significant (p<0.05) correlation. Correlation between TL and Hg-T (r = 0.37286) and between W and Hg-T (r = 0.38212) were positive and significant (p<0.05). Two-way ANOVA (n = 81) showed that TL and W had significant difference (p<0.05) among seasons. The Hg-T showed differences in relation to the factor season (p<0.05). The correlation between Hg-T and rainfall showed a negative and significant relation (r = -0.56; p<0.05). Rainfall strongly influenced the bioacumulation of mercury in this species. Dryer months showed relatively higher mercury concentrations than the end of the rainy season. Less rainfall, and consequently less particulate matter and less primary production in the estuary, make mercury more bioavailable. Fish from this estuary are fit for human consumption at all times of the year.

scholarly journals Seasonal morphological variation of the vas deferens of scorpion mud turtle (Kinosternon scorpioides)

2014 ◽  
Vol 14 (3) ◽  
Author(s):  
Diego Carvalho Viana ◽  
Leandro Almeida Rui ◽  
Amilton Cesar dos Santos ◽  
Maria Angélica Miglino ◽  
Antônio Chaves de Assis Neto ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Rainy Season ◽  
Vas Deferens ◽  
Microscopic Analysis ◽  
Lipid Vesicles ◽  
Dry Season ◽  
Transmission Electron ◽  
Cellular Debris ◽  
Mud Turtle ◽  
Dry Seasons

This study aimed to characterize the morphology of the vas deferens ofKinosteron scorpioides by macroscopic and microscopic analysis. Were used 20 adult male jurarás collected at regular intervals during the year and divided into four experimental groups in the rainy and dry seasons, being processed for light microscopy, scanning electron microscopy and transmission electron microscopy. Morphometry for tubular and luminal diameters and epithelial height were also performed. On rainy season, vas deferens presented pseudostratified epithelium with cylindrical cells, spermatozoids and milky fluid in the lumen, with cytoplasmic organelles and lipid vesicles. On dry season, epithelium was pseudostratified with cuboid cells, with cellular debris and no spermatozoids. There was significant variation (p<0,05) for morphometry of vas deferens, with lower values of tubular and luminal diameters on rainy season, and higher epithelial height on dry season.

scholarly journals Effects of Depth and Seasons on the Physicochemical and Bacteriological Quality of Selected Well Water Samples in Awka Urban, Anambra State, Nigeria

2020 ◽  
pp. 1-28
Author(s):  
M. U. Orji ◽  
S. C. Onuorah ◽  
M. O. Ifemeje ◽  
O. R. Umeh
Keyword(s):  
Water Samples ◽  
Rainy Season ◽  
Salmonella Typhi ◽  
Dry Season ◽  
Well Water ◽  
Frequency Of Occurrence ◽  
Proteus Vulgaris ◽  
Anambra State ◽  
Dry Seasons

Background: The people of Awka urban show an increasing trend of using well water resulting to unreliable and quality-compromised water supply. Aim: Effects of depth and seasons on the physicochemical and bacteriological quality of selected well water samples in Awka urban, Anambra State was conducted to determine their quality and suitability for domestic uses. A total of thirty shallow and deep well water samples were collected during the rainy and dry seasons. Methods: Physicochemical analysis was carried out using standard analytical methods. The total bacterial count was determined by dilution method. Results: Some of the physicochemical parameters (PH, dissolved oxygen, nitrate, cadmium, lead and arsenic) exceeded the World Health Organization maximum containment levels indicating that the samples were unfit for domestic uses. The bacterial counts ranged from 2.66 to 3.26 logcfu/ml during the rainy season and 2.54 to 3.20 logcfu/ml during the dry season. The total coliform counts also exceeded the W.H.O levels. Citrobacter freundii, Shigella flexneri, Serratia marcescens, Proteus vulgaris, Vibrio cholerae, Salmonella typhi, Pseudomonas aeruginosa, Escherichia coli and Bacillus subtilis were isolated during both seasons and identified using standard analytical procedures. The bacterium that had the highest frequency of occurrence during the rainy season was Citrobacter freundii (16.55%) while Salmonella typhi had the highest frequency of occurrence during the dry season (17.69%) respectively. Proteus vulgaris had the least frequency of occurrence 5.41% and 4.62% during the rainy and dry seasons respectively. The results were analyzed statistically using two-way analysis of variance. Higher bacterial counts were recorded in rainy season and shallow wells than dry season and deeper wells. Conclusion: The presence of these bacteria above admissible limits showed that the water lacked proper water management services and may be harmful to humans. There is therefore a need to monitor the well water quality by employing better sanitary practices and subjecting the waters through various forms of water treatments before use to help prevent disease outbreak.

scholarly journals Pediatric infectious diseases admissions: Sex differences and seasonal variations

2021 ◽  
Vol 015 (02) ◽  
pp. 049-058
Author(s):  
Samuel Olorunyomi Oninla ◽  
Michael Olaniyan Onigbinde ◽  
Akinyemi Olaleye Fadugbagbe ◽  
Emmanuel Olaseinde Bello ◽  
Omolayo Adebukola Olubosede
Keyword(s):  
Sex Differences ◽  
Infectious Diseases ◽  
Seasonal Variations ◽  
Rainy Season ◽  
Malaria Incidence ◽  
Relevant Information ◽  
Dry Season ◽  
Incidence And Mortality ◽  
Significant Difference ◽  
Dry Seasons

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.

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