Hidrología: investigaciones actuales

The 1988 and 1998 flood events hit Bangladesh which was more catastrophic in the present study area, Manikganj district. The Jamuna River has great locational influences to cause severe flood situations in the study area. Bangladesh Water Development Board (BWDB) provided the river stage data of the Jamuna for pivot table analysis and drawing hydrographs. The Jamuna River attained its highest peak 10.55 m in August and 10.58 m in September in 1988 flood at Arichaghat station which flowed 141 cm and 144 cm above its danger level (9.14 m). In 1998 flood event, the Jamuna rose up to 10.02 m in July, 10.35 m in August and 10.76 m in September that flowed respectively 88 cm, 121 cm and 162 cm above the danger level (9.14 m). As a whole, the Jamuna flowed above the danger level for 43 days in 1988 and 68 days in 1998 causing the devastating flood in the study area. A total of 2518 people lost their lives and damage to crops fisheries, livestock, was over 120 billion US dollar. About 125 km of local roads, national highways and several hundred bridges, over 250 educational institutions and 140 health structures were affected by the flood events.

This paper estimates the runoff sensitivity to change in temperature and rainfall by using Soil and Water Assessment Tool (SWAT) hydrologic model. Rainfall and temperature were perturbed to study the runoff sensitivity to these climate variables. Rainfall and Temperature play main role in the accessibility of runoff by influencing the contribution and timing of water sources. The SWAT model was run with monthly station-based temperature and rainfall data for the whole upper awash sab-basin (1980-2010). The hydrological model was calibrated for eight years (1993-2000), and the simulation results were validated with the historical stream-flow for four years (2001-2005) at outlet of Hombole gauging station. The impact of temperature and rainfall changes on the runoff in the sub-basin was estimated by using a sensitivity analysis; through the calibrated and validated SWAT hydrological model. The SWAT model has been used to study the impact of possible hypothetical scenarios of rainfall and temperature on the annual runoff of the Awash sub-basin. This was achieved through both separated and combined use of changes in the amount of rainfall (+/-20% and increase temperature (warming of up to 5°C). The results shown that runoff was sensitive to rainfall and temperature changes in the study area. It has been revealed that 1, 2, 3, 4 and 5°C increases of the annual temperature lead to reduces annual runoff by -0.085, -0.88, -1.75, -2.55 and -3.30% respectively. The runoff has a positive correlation with rainfall change; but, a negative correlation with temperature change. The results reveal that runoff was more sensitive to rainfall than that of temperature rise. Increased/decreased rainfall by 10% will result in increased/reduced annual runoff by 22% and 21% respectively. Generally, the results showed that changes in the climate variables had a significant effect on water availability.

This study evaluates the chemical properties of Shitalakshya River water bodies based on its chemical parameters such as Total Suspended Solids (TSS), pH, Electic Conductivity (EC), Total Dissolved Solids (TDS), Dissolved Oxygen (DO), Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Nitrogen (N), Chlorine (Cl), Total Phosphorous (P), Sulfur (S), Potassium (K). To do this chemical analysis, pre-monsoon and postmonsoon seasons were considered to collect the samples from this river. This analysis shows that Total dissolved solids (TSS) of this river in both seasons have crossed the standard limit announced by WHO. The pH is less enough in the pre-monsoon season and in post monsoon it is up to the standard value. EC and Phosphorous both have crossed the standard value of drinking water in the Shitalakshya River. Nitrogen is too much less although it is a vital element. TDS, DO, BOD, COD, Cl, and S are approximately under the range of standard limits. The parameters that are high should be reduced in a proper treatment method so that this water can be used both for agricultural and drinking purposes.

The present study was aimed at assessing the Physico-chemical parameters viz., temperature, Electrical Conductivity (EC), pH, turbidity, Total Alkalinity (TA), Total Hardness (TH), Total Dissolved Solids (TDS), Dissolved Oxygen (DO); Chloride, Potassium, Zinc, Copper, Total Iron, BOD, COD, Oil, and Grease at in Alard College Campus, situated in Hinjewadi, Pune. The aim of the work under the title is to analyze the College Campus water outlet, by dividing it into various sampling station. Water quality in the study area was found to have high value of pH, EC, TDS. A systematic correlation in this study showed that there was a significant linear relationship among different pairs of water quality parameters. It was concluded that the TDS, EC and pH are important physicochemical parameters of water quality and are correlated with most of the other parameters. The present study also identifies the critical pollutants affecting the campus water quality.

The scope for installation of large and medium irrigation projects is limited due to lack of availability of proper sites, paucity of funds, equity issues and other social factors in many regions of the country. Therefore, the installation of ‘determination and demarcation of suitable through watershed area for artificial recharge and rainwater harvesting’ for ground water recharge and water harvesting has a great potential in the times to come and the objectives like harvesting every drop of rainwater for purposes of irrigation to create sustainable sources of income for the village community as well as for drinking water supplies. The study of project area i.e., Patan Block, Gundrdehi and Durg block their rainfall, temperature, humidity and also the recommended for artificial recharge and rainwater harvesting with harvesting structures. With the results of the project i.e., the changes in crop production, ground water level and human community improvement is positively. The essential and overall view of the project to development of ground water level, production of crop and also reduced in soil erosion and also the concluded. The best way to manage rain water is to conserve, store and use it right in the field where it is received. Excess water can be stored in small farm reservoirs. Field experience in this regard has clearly demonstrated that it is possible to almost double the cropping intensity and crop production by storing e xcess rain water in a small reservoir which can save paddy crop from intermittent droughts, allow fish culture during rainy season and help in establishing and or giving lifesaving irrigation to the second crop in post rainy season on deep soils. Harvesting every drop of rain water for purposes of irrigation, plantations including horticulture and floriculture, pasture development, fisheries etc. to create sustainable sources of income for the village community as well as for drinking water supplies. Identify rainfall pattern and distribution with the subsequent drainage system in the prevalent area. To prevent run-off of rain water. To develop methods to increase water retention, conservation and prevent soil loss. Improvise methods to augment water recharging of the land and soil. To encourage restoration of ecobiological balance in the region. To minimize the drought effect by means of soil and water conservation and augmentation of water recharging. To promote economic development of the village communities in the region. Special emphasis to improve the economic and social condition of the poor and disadvantaged sections in the area. To increase the level of ground water table in the area. To reduce run-off velocity in the area in order to check the erosion of fertile upper crust of earth. To improve the water infiltration rate. To control the problem of soil erosion. To control flooding in the agricultural fields.

Background: Schistosomiasis is a snail-borne, water-based parasitic infection caused by blood-dwelling (hence called blood-fluke) trematode worms of the genus Schistosoma. It is a disease of the poor and marginalized. Schistosomiasis remains an important public health problem globally with approximately 779 million estimated to be at risk. This study was carried out to ascertain the prevalence of the disease among school children in the three communities: Owena, Kajola and Baiken with a view to providing important parasitological information and boosting can sustainable control strategies of the disease.
Methods: A school based cross-sectional technique was used to collect data on risk factors from 624 school children in March 2014 and 591 in April 2015. Urine samples were collected between the hours of 10:00 am 12:00 pm GMT in dry labeled wide mouthed. Plastic urine container (300-500 ml) each 10 ml was centrifuged and examined for the presence or absence of more nutobiuk eggs. Using X40 objectives of a light microscope. Infection intensity was recorded as number of eggs per 10 ml of urine sample. The intensity of infection was graded as heavy 500 eggs/10 ml urine, moderate (51-499 eggs/10 ml urine) or light (50 eggs/10 ml urine). Data obtained were analyzed using version 20.0 of the Statistical Package for The Social Sciences (SPSS) for windows Software Packages (SPSS on Chicag oil, 2013).
Results: Our of the 624 pupils examined in 2014, 256 (41.0%) were positive for S. haematobium eggs in urine, while in 2015, 381 (64.5%) out of 591 were positive. Thus, there was a 23% increase in prevalence between the two genera. Individual intensity of infection varied from 1-6, 468 eggs/10 ml urine. Meaning the most heavily infected pupil in 2015 exceeded more than 68% infection in 2014. The arithmetic memory 2016 in moles was 0.65 in 2015 it was 0.09, while that of females in 2014 was 0.05 and 0.08 in 2015.
Conclusion: This study area in Owena, Kajola and Baiken communities bordering Owena Reservoir/Dam, Ondo East Local Government Area, Ondo State, Nigeria show risk communities for urinary schistosomiasis. The overall pattern of S. haematobium eggs per 10 ml urine in the three communities in the two years (March 2014 and April 2015) study shows that it was sex and age dependent. The age-group with highest prevalence is 11-15 years in 2014 and 55.4% in 2015 with range infection for males was 43.6% in 2014 and 71.86 in 2015, while that of females was 37.0% in 2014 and 57.0% in 2015. Therefore, it is recommended that all school-age children especially those in 11-15 age-group should be treated using chemotherapy method. Pipe-borne water to prevent people having contact with the infected fresh water, sewage disposal facilities provided, mass educational therapy (societal sensitization/ health education) is required to reduce infection and transmission of urinary schistosomiasis.

This study presents the differences and similarities between the MODFLOW-USG (Unstructured Grid version of MODFLOW) and traditional structured versions of MODFLOW 2005 in simulating a three-dimensional multilayer groundwater flow model in Quaternary aquifer east Nile delta in Egypt. A 390-borehole dataset was used to build a three-dimension stratigraphic model of the Quaternary aquifer. GIS-based conceptual model is mapping to represent the different boundary conditions such as lakes, river, drains, aquifer recharge, and discharge. The conceptual model is exported to the stratigraphic model; therefore, boundary conditions data are automatically arranged in arrays identical with the grid cells. MODFLOW 2005 and MODFLOW USG are combined with the computer-based program PEST to calibrate groundwater head distribution through the aquifer system. Groundwater levels measured in 1991 are used for the steady-state calibration and are employed then as initial conditions for the transient calibration between 1991 and 2004. The heads measured in 2015 are used for more model verification. The results show that MODFLOW-USG provides flexibility in grid design, including the capability to use nonrectangular cell shapes. Also, it can be used with simple grids and nested grids that allow for the solution to be focused in areas of interest. Also, the results show that the MODFLOW-2005 simulation takes about 20 times longer to complete the run and uses about 6 times more cells number than the MODFLOW-USG simulation.

The quantity of water is as important as the quality, since these affect the quantity and the quality of available water, water quality is used to express the suitability of water and sustainable to various uses or processes. It is affected by a wide range of natural and human influences, the most important of the natural influences is hydrological influence. The water qualities study was carried out in Ibadan using three landuse (urban, peri urban and rural) in slum areas of Ibadan were evaluated for these physicochemical parameters: temperature, total dissolved solid (TDS), pH, and dissolved oxygen (DO), from well, borehole, water from vendor or pipeborne, from 8 localities and 3 LGA in Ibadan. The results showed variations in the water quality parameters the slum areas. Water pH is lowest in Awotan and Apete of Ido LGA water source which makeup rural slums landuse. with water pH of 5.7 well and 5.8 borehole which is acidic, there is highest value of conc of Lead in these areas of (0.259 mg/l) compared to other landuse and locality, water is of best quality among water from vendors. Using the sig value of 0.05, that is no sig difference between the water quality in slum areas and WHO standards. Using Anova with physico-chemical parameters of water temperature, pH, dissolved oxygen, total dissolved solids, conc of zinc, and iron also having no significant. But a significant spatial variation of water quality of Lead concentration with the sig value of 0.033 and F value of 2.983. There is significant variation in different water source of water pH, total dissolved solid and dissolved oxygen. a sig value of 0.028, 0.031, and 0.000 respectively.

This study was undertaken in Kitui South in Kitui County in the south eastern parts of Kenya. The main objective of the study was to develop a spatial model that can be used for selection of suitable sites for sand dam in Kitui South. The study also assessed the spatial variation of sand grain sizes and how these determine the suitability of sites for the sand dams. Data analysis was done using three approaches. The first approach involved the use of the Remote Sensing (RS) technique where data was preprocessed and analyzed using Erdas Imagine software and Geographical Information Systems (GIS) for spatial modelling. The distribution of sand particle-sizes was based on sieve analysis on the sand samples collected from seasonal rivers in the study area. The seasonal rivers that were investigated in this study included Mwila, Kakya, Wiitu, Nguni, Ngunyumu, Muvuko, Kanzilu, Masaa, Katiliku, Ngulungu, Nzeeu, Koma and Katitika. Statistical analysis was done to establish the relationships between the various spatial components affecting sand particle distribution. The results from the spatial model which integrated all factors shows that 16% of the studied sites along the seasonal rivers in Kitui South were fairly suitable for construction of sand dams while 79% were classified as suitable and 5% are categorized as very suitable. Several sites in the central and the entire eastern parts of Mutha Ward were found not suitable for sand dam construction due to poor conditions such as the lack of suitable sand particles, lack of bedrock exposure on the riverbeds, flat terrain, very shallow stream banks, and weak soils on the riverbanks. Suitable sites for sand dams were found on the western and central areas of Kitui South where production and high accumulation of coarse sands was observed along the seasonal rivers. The areas near Mutomo hills and the rocky areas in Ikanga wards were found to be characterized by few excellent sites for sand dams. The optimum accumulation of different grades of sand in the seasonal rivers was found on streams with slope of between 1.5 and 6% that were dominated with 0 to 40% coarse sands, 0 to 30% fine gravels, 0 to 20% fine sands, and 20 to 80% medium sands. The accumulation of fine gravels was found to be closely related to the distribution of D30, D60 and D90 sand particle-sizes (0.4-4 mm) while accumulation of coarse sands showed good relationship with the distribution of the medium size sand (0.2-0.4 mm). The accumulation of medium sands was equally high when the occurrence of coarse sands was minimal. Different grades of sand were found to be strongly influenced by the changes in the elevation of the stream especially with regard to the accumulation of the medium sands (r=0.76) and coarse sands(r=0.75). Out of 80 investigated sites, 59% of them were dominated with uniform sands (Cu<3), 30% were intermediate sands and only 11% were wellgraded sands (Cu>5). The study also found that 86% of the sites along the seasonal streams were dominated with medium sands while 10% were dominated with fine sands and the rest (4%) dominated by coarse and gravelly sands. From the results this study concludes that 59% of the 80 sites that were investigated in this study have a high potential for providing suitable sites for sand dams in Kitui South.