Water In Rainy Season Research Articles

Spatial and temporal dynamics of the hydrology at Salinas Bay, Costa Rica, Eastern Tropical Pacific

Introduction: Salinas Bay is located in the warm pool of the Eastern Tropical Pacific (ETP), characterized by warm, shallow surface waters, a strong and shallow thermocline, and an important biological diversity. The primary productivity of the region is influenced by the coastal upwelling, which occurs during the boreal winter as a result of the strengthening of trade winds.
 Objective: To study the spatial and temporal dynamics of physical and chemical parameters at seven hydrographic stations in Salinas Bay, Costa Rica, through the analysis of CTD data, and relate the warm and cold events to the regional atmospheric conditions present when measuring the data.
 Methods: Seven hydrographic stations, sampled at Salinas Bay between August 2008 and December 2014, were selected. The variables processed for analysis are temperature, density, salinity, oxygen, chl-a and turbidity. Once the data was processed, 42 Hovmöller kind diagrams were plotted.
 Results: All variables, except turbidity, presented a seasonal periodicity associated with the upwelling. In general, colder and denser waters, higher salinity and chl-a concentrations and lower dissolved oxygen values were observed during the dry season, when the upwelling was active. Whereas, during the rainy season water masses were warmer and less dense, salinity and chl-a concentrations decreased and dissolved oxygen values tended to increase.
 Conclusions: The spatial and temporal dynamics of the hydrology in Salinas Bay was influenced by the coastal upwelling events. The region also presented an interannual variability associated with ENSO. Seasonal and interannual variability can counteract their effects on the oceanographic parameters when they coincide temporally.

Seasonal Variation of Rainy and Dry Season Per Capita Water Consumption in Freetown City Sierra Leone

Ensuring a sustainable urban water supply for developing/low-income countries requires an understanding of the factors affecting water consumption and technical evidence of individual consumption which can be used to design an improved water demand projection. This paper compared dry and rainy season water sources available for consumption and the end-use volume by each person in the different income groups. The study used a questionnaire survey to gather household data for a total of 398 households, which was analysed to develop the relationship between per capita water consumption characteristics: Socio-economic status, demographics, water use behaviour around indoor and outdoor water use activities. In the per capita water consumption patterns of Freetown, a seasonal variation was found: In the rainy season, per capita water consumption was found to be about 7% higher than the consumption for the full sample, whilst in the dry season, per capita water consumption was almost 14% lower than the full survey. The statistical analysis of the data shows that the average per capita water consumption for both households increases with income for informal slum-, low-, middle- and high-income households without piped connection (73, 78, 94 and 112 L/capita/day) and with connection (91, 97, 113 and 133 L/capita/day), respectively. The collected data have been used to develop 20 statistical models using the multiple linear stepwise regression method for selecting the best predictor variable from the data set. It can be seen from the values that the strongest significant relationships of per capita consumption are with the number of occupants (R = −0.728) in the household and time spent to fetch water for use (R = −0.711). Furthermore, the results reveal that the highest fraction of end use is showering (18%), then bathing (16%), followed by toilet use (14%). This is not in agreement with many developing countries where toilet use represents the largest component of indoor end use.

Water Quality and Pollution Index in Grenjeng River, Boyolali Regency, Indonesia

<p>Grenjeng River is one of the irrigation water resources which is currently polluted by waste from industrial, livestock and domestic activities. This study aims to assess the quality and index of water pollution based on physical-chemical and biological parameters in the Grenjeng River, Boyolali Regency. Sampling of river water was carried out in dry and rainy seasons which were taken at three observation stations (upstream, middle stream and downstream). Results from laboratory analysis were compared with water quality standards according to Government Regulation No.82/2001, and quality status was based on the Pollution Index method in accordance with the attachment to Minister of Environment Decree No.115/2003. This study shows that BOD of 53-5.7 mg L<sup>-1</sup>, COD of 49-510.5 mg L<sup>-1 </sup>and total coliforms of 540-2,400,000 mLin dry season have exceeded the quality standard water classes, while in rainy season total coliforms 24,000-240,000 mLhave exceeded the standard water for all water classes. The pollution index of the river water in dry season has reached polluted to extremely polluted levels and the index of the river water in rainy season has reached moderately polluted to polluted levels. This condition shows that the practice of dumping waste into river bodies can directly affect river water quality. The irrigation water source for agricultural must comply with irrigation water quality standards so that is suitable as irrigation water for plants. Environmentally friendly approach is needed to prevent worse pollution, which is done by increasing public awareness and business actors in managing liquid waste by making the integrated wastewater treatment system.</p>

Studi Potensi Air Buangan Permukaan Perkotaan Sebagai Sumber Air Irigasi

Indonesia geographical location (60LU-110LS) causes most of its region experience heavy amount of rainfall. Overflowing rain water is consequently ample in amount, and potentially a great source for irrigation. Both urban and subburbs part of Medan, where some primary livelihood is in agriculture, benefit from this natural event. However the level of availability all year is not certain. Too much in rainy season means flood, and too little means drought in dry season. Farmers normally neglected the importance of storing rain water in rainy season in order to supply the dry season, and thus becomes problem for farmers. How much water can potentially be used for agriculture in urban area, what is the relationship between water amount with soil texture, types of certain-soil-suitable crop, plant growth period. This research aims to analyze and answer this particular question.

Biological efficacy and toxic effect of emergency water disinfection process based on advanced oxidation technology.

An innovative and removable water treatment system consisted of strong electric field discharge and hydrodynamic cavitation based on advanced oxidation technologies was developed for reactive free radicals producing and waterborne pathogens eliminating in the present study. The biological efficacy and toxic effects of this advanced oxidation system were evaluated during water disinfection treatments. Bench tests were carried out with synthetic microbial-contaminated water, as well as source water in rainy season from a reservoir of Dalian city (Liaoning Province, China). Results showed that high inactivation efficiency of Escherichia coli (>5 log) could be obtained for synthetic contaminated water at a low concentration (0.5-0.7 mg L(-1)) of total oxidants in 3-10 s. The numbers of wild total bacteria (108 × 10(3) CFU mL(-1)) and total coliforms (260 × 10(2) MPN 100 mL(-1)) in source water greatly reduced to 50 and 0 CFU mL(-1) respectively after treated by the advanced oxidation system, which meet the microbiological standards of drinking water, and especially that the inactivation efficiency of total coliforms could reach 100%. Meanwhile, source water qualities were greatly improved during the disinfection processes. The values of UV254 in particular were significantly reduced (60-80%) by reactive free radicals. Moreover, the concentrations of possible disinfection by-products (formaldehyde and bromide) in treated water were lower than detection limits, indicating that there was no harmful effect on water after the treatments. These investigations are helpful for the ecotoxicological studies of advanced oxidation system in the treatments of chemical polluted water or waste water. The findings of this work suggest that the developed water treatment system is ideal in the acute phases of emergencies, which also could offer additional advantages over a wide range of applications in water pollution control.

Analysis of Water Quality Using Chemical Parameters and Metal Status of Balu Rivers’ Water at Dhaka, Bangladesh

Balu River at Dhaka city has become polluted due to industrial effluents, untreated sewage and municipal waste. The chemical parameters and metal status of water of Balu River at surface water level and subsurface water level at ten different locations (twenty samples) were studied during winter and rainy seasons in 2008. In the winter season, the mean value of Sodium was 12.41±2.17; Magnesium was 3.73±0.38; Chloride was 144.07±17.49; Nitrate was 7.04±1.01; Bicarbonate was 294.57±50.47 and Sulphate was 25.55±3.85 at surface water level. The concentration of the chemical parameters of River water in rainy season is less than that of winter season except Sodium (22.51±3.71) and Calcium (22.66±1.80). In the winter season, the mean value of Copper was 0.16±0.04; Chromium was 1.02±0.24; Zinc was 0.38±0.08 and Iron was 0.16±0.02 at surface water level. In the rainy season, the mean value of Copper was 0.08±0.04; Zinc was 0.05±0.02; and Iron was 0.04±0.02. The concentration of the metals of river water in rainy season is less than that of winter season. A significant positive correlation was found between Sodium and Chloride while significant negative correlation was found between Sodium and Iron, Zinc and Copper. Results suggest that river water was found unsuitable for drinking, domestic and irrigation purposes in respect to Chromium and Bicarbonate contents.

盐城海滨湿地景观演变关键土壤生态因子与阈值研究

The key ecological factors influencing the evolution of coastal wetland landscape were investigated by soil sampling and analyzing,and analyses on data from ETM + by methods of grey relative analysis,linear regression and geostatistics in the Yancheng national natural reserve as an example. The ecological thresholds were defined based on the analyses on the relationship between the spatial distribution and landscape types.( 1) The physiochemical properties of soil at the coastal wetland exert distinct continental and oceanic difference, depending on their specific location and corresponding vegetation types. Soil water content and salinity shows a trend of decrease from Spartina marsh to salsa,and to reed. The soil water content was higher in wet season than in dry season,in contrast,the salinity exhibited lower average value in wet season than in dry season. The soil organics and nutrient content show higher values in Spartina marsh and reed,while lower in salsa,and generally higher in wet season than dry season,with an exception for the soil available phosphorus.( 2) Through the grey relative analysis,the rank of the correlation between the wetland soil physicochemical characteristic and landscape evolution follows: in the dry season water salinity ammonium nitrogen available potassium organics available phosphorus; in the rainy season water salinity available phosphorus ammonium nitrogenavailable potassiumorganics. Therefore the soil water content and salinity were identified as the key ecological factors that influence the evolution of coastal wetland landscape.( 3) The spatial distribution of soil water content and salinity show the same trend and was classified into five grades,with the variation higher in the eastern-western direction than in the southern-northern direction.( 4) Combined with analyzing distribution of soil water content and salinity and the correlated landscape types,the range of thresholds of soil water content and salinity were defined. The soil water content and salinity were less than 42. 33% and 0. 745% respectively for reed soil; 38. 836% —46. 593% of soil water content and 0. 403% —1. 314% for salsa soil; Spartina marsh soil had water content of above 39. 475% and salinity above 0. 403%; with the soil water content and salinity of more than 41. 550% and 0. 656% for optical flat soil.

Bacteriological Pollution of Artesian Ground Water Sources Used by Local Communities Living in and Around Bukavu Town (Democratic Republic of Congo) as Sources of Potable Drinking Water

Pollution of water for human consumption is a major environmental challenge in hundreds of towns across Sub-Sahara Africa. The objective of this work was to evaluate the degree of bacterial pollution of ground water sourcesas sources of safe drinking water consumed by local human communities living in urban and peri-urban zones of Bukavu town (eastern DR Congo). Populations living in these zones are generally disfavored in terms of safe watersupply services by the national water corporation (REGIDESO). This study was conducted in 2011 during the dry and rainy seasons from 15 ground water sources used by the population from these peri-urban zones as sources of safe drinking water and as source of safe water for other domestic needs. In total, 150 samples were taken from these water sources. During both rainy and dry seasons, 5 water samples were taken for every source. These samples were analyzed for their physic-chemical and bacteriological properties in comparison to world health organization standards. Results indicated that the degree of bacterial pollution of water was high (T=4.56, P<0.05) during rainy season (20.6 ± 25.3 total coliforms/100 ml of water on average) than during the dry season (3.10 ± 6.023 total coliforms/100 ml of water on average) across all sources studied. Sources (sites) that were highly polluted included Mulehe I, Kaliba, Kahuranyi, Cemu, Bagira, Funu et Gihamba. Overall, bacterial pollution of drinking water sources was significantly (P<0.05) high during the rainy season than during the dry season. Similarly, cholera epidemic outbreak is high in these zones during the rainy season (September-December). In November-December 2011, more than 400 cases of death were registered in hospital and the victims were from these highly polluted areas where the study was conducted. In fact, the presence of Vibrio cholerae was detected in all rainy season water samples from these areas. The results of this study indicated that Vibrio cholerae is the principal dangerous pollutant agent of these drinking ground water sources used by more than half million people living in peri-urban areas and in over-populated areas in Bukavu town. There is a need to set a system of monitoring water quality for human consumption. Results (findings) of such a monitoring program may be used to inform policy makers and health agents on better strategies to control water pollution in Bukavu and in related Sub-Sahara African towns. There is a need for policy makers to develop new strategies to improve water sanitation and supply everyone safe drinking groundwater in Bukavu Town. The adoption of water sanitation, rainwater harvesting technologies may help in areas where the national water corporation can’t be able to supply water in short to mid terms.

Energy partitioning over the West African savanna: Multi-year evaporation and surface conductance measurements in Eastern Burkina Faso

Seasonal variability of the energy partitioning was analyzed with a combination of eddy fluxes of sensible and latent heat and weather data on intensely farmed land in the savanna area of Eastern Burkina Faso, West Africa. The analysis covers two rainy seasons (May-October 2003 and 2004), one dry season (December-April 2004), one dry to wet transition period (May-June 2004) and two wet to dry transition periods (October-November 2003 and 2004). This is the first long-term flux measurement reported upon for this part of the world. The inter-annual partitioning of the available energy between the latent heat (actual evaporation) and sensible heat flux shows a conservative relationship between a decrease in annual rainfall (33%) and the sum of the increase in sensible heat flux (20%) and decrease in latent heat flux (10%). The latent heat flux was the main consumer of the available energy during the rainy season (71%), while sensible heat flux was dominant during the dry season (77%). In terms of the rainy season water balance, 1229 mm of rainfall was observed in 2003, of which 351 mm evaporated, while 825 mm of rainfall was observed in 2004, of which 268 mm evaporated. During the dry season, the latent heat flux was strongly coupled to the atmosphere, with the decoupling coefficient (?) ranging from 0.18 to 0.4. These low values were due to low soil moisture availability and high vapor pressure deficit (VPD > 4 kPa). During the rainy season, the latent heat flux was decoupled from the atmosphere (0.6 ? ? <0.9). Following this pattern of coupling and decoupling, a new formulation of actual evaporation and surface conductance was proposed. The results are thought to be relevant inputs for eco-hydrological models in the semi-arid region of West Africa.

Regreening of Desiccated Leaves of the Poikilochlorophyllous Xerophyta scabrida upon Rehydration

The poikilochlorophyllous and desiccation tolerance nature of the leaves of the monocotyledonous Xerophyta scabrida and the physiological recovery of the air-dried leaves upon rehydration after a long-term desiccation is described in this paper. Water uptake through the leaf surface upon rehydration was found to be of prime importance for recovery. Field observations in the natural habitat showed that at the onset of the rainy season water uptake through the leaf surface preceded the development of new adventitious roots. In dry leaves carotenoids were found as the only photosynthetic pigments. Upon rehydration de novo chlorophyll and carotenoid synthesis began just before the leaves reached their maximum water content and specific leaf area. The accumulation of chlorophylls and carotenoids was found to rise very fast and maximum content was reached about 72 hours after rehydration. The values of the chlorophyll fluorescence ratio, F690/F735, and of the fluorescence intensities at 690 nm and at 730 nm (both at maximum Fm and steady-state fluorescence Fs) continuously decreased from the begin of regreening until reaching maximum chlorophyll content after 3 days. The fluorescence ratio F690/F735 proved to be a very suitable non-destructive diagnostic method to monitor the chlorophyll content during regreening of the poikilochlorophyllous leaves of X. scabrida upon rehydration.