Current Issue : April - June Volume : 2015 Issue Number : 2 Articles : 7 Articles
Ndarugu River, Kenya, during its course through the different agricultural and industrial areas of\nGatundu, Gachororo and Juja farms, receives untreated industrial, domestic and agricultural waste\nof point source discharges from coffee and tea factories. During wet season the water is also polluted\nby non-point (diffuse) sources created by runoff carrying soil, fertilizer and pesticide residues\nfrom the catchment area. This study involved the calibration of water quality model QUAL2K\nto predict the water quality of this segment of the river. The model was calibrated and validated\nfor flow discharge (Q), temperature (T), flow velocity (V), biochemical oxygen demand (BOD5),\ndissolved oxygen (DO) and nitrate (NO3-N), using data collected and analyzed during field and laboratory\nmeasurements done in July and November-December 2013. The model was then used in\nsimulation and its performance was evaluated using statistical criteria based on correlation coefficient\n(R2) and standard errors (SE) between the observed and simulated data. The model reflected\nthe field data quite well with minor exceptions. In spite of these minor differences between\nthe measured and simulated data set at some points, the calibration and validation results are acceptable\nespecially for developing countries where the financial resources for frequent monitoring\nworks and higher accuracy data analysis are very limited. The water is being polluted by the\nhuman activities in the catchment. There is need for proper control of wastewater by various\ntechniques, and preliminary treatment of waste discharges prior to effluent disposal. Management\nof the watershed is necessary so as to protect the river from the adverse impacts of agricultural\nactivities and save it from further deterioration....
Drought is one of the major natural disasters in the world which has a lot of social and economic impacts. There are\nvarious factors that affect climate changes; the investigation of this incident is also sensitive. Climate scenarios of future\nclimate change studies and investigation of efficient methods for investigating these events on drought should be\nassumed. This study intends to investigate climate change impacts on drought in Karoon3 watershed in the future. For\nthis purpose, the atmospheric general circulation models (GCM) data under Intergovernmental Panel on Climate\nChange (IPCC) scenarios should be investigated. In this study, watershed drought under climate change impacts will be\nsimulated in future periods (2011 to 2099). In this research standard precipitation index (SPI) was calculated using\nmean monthly precipitation data in Karoon3 watershed. SPI was calculated in 6, 12 and 24 months periods. Statistical\nanalysis on daily precipitation and minimum and maximum daily temperature was performed. To determine the\nfeasibility of future periods meteorological data production of LRAS-WG5 model, calibration and verification was\nperformed for the base year (1980-2007). Meteorological data simulation for future periods under General Circulation\nModels and climate change IPCC scenarios was performed and then the drought status using SPI under climate change\neffects analyzed. Results showed that differences between monthly maximum and minimum temperature will decrease\nunder climate change and spring precipitation shall increase while summer and autumn rainfall shall decrease. The most\nincrease of precipitation will take place in winter and in December. Normal and wet SPI category is more frequent in\nB1 and A2 emissions scenarios than A1B. Wet years increases in the study area during 2011-2030 period and the more\ncontinuous drought years gradually increases during 2046-2065 period, the more severe and frequent drought will occur\nduring the 2080-2099 period....
The Bagula site is located in Dhanabd district in the central part of Jharkhand state. After formation of a new state Jharkhand, rapid urbanization and development in the area of study has caused increase on demand for water supply. The monitoring of the groundwater level exhibits a decreasing trend of water level. The main reason for this decline in the groundwater table is that well pumping from groundwater resource has exceeded natural recharge in the recent years. In this research the aquifer of this hard metamorphic terrain has been studied by the geo electrical method. The need for this work is studying groundwater conditions for protecting groundwater supplies as a unique source of water for this area. Electrical resistivity survey was carried out in order to study groundwater conditions in the hard metamorphic rocks and aquifer depth, thickness and location of the aquifer. Also zones with high yield potential have been determined based on the resistivity information. Thirty five (35) vertical electrical soundings by Schlumberger array were conducted at eight different localities of metamorphic rock area. The resistivity data confirm that the study area is mainly based on un-confined aquifer condition. These data were used to determine the depth and nature of the aquifer and the boundaries of the aquifer with a reasonable accuracy....
There is spontaneous heating of coal in mining areas of coal fields. A systemic study on the physical-chemical characteristics of waters from 20 samples of non-fire and fire zone has been carried out to assess the impact of spontaneous heating of coal on the quality of water. A total of 11 water quality parameters were evaluated. The study reveals that in the coal seam fire area, the dissolved oxygen has depleted and the electric conductivity and total dissolved solids have increased beyond the limits in the water. Magnesium and sulphate were more than permissible limits of ISI. It was observed that the coal seam fire does not only damages valuable resources of nation, but it also degrade/deteriorate the quality of water, which can produce adverse effects on the inhabitants residing in and around fire zone area....
The increasing effort to develop and apply nonstationary models in hydrologic frequency analyses under\nchanging environmental conditions can be frustrated when the additional uncertainty related to the\nmodel complexity is accounted for along with the sampling uncertainty. In order to show the practical\nimplications and possible problems of using nonstationary models and provide critical guidelines, in this\nstudy we review the main tools developed in this field (such as nonstationary distribution functions,\nreturn periods, and risk of failure) highlighting advantages and disadvantages. The discussion is supported\nby three case studies that revise three illustrative examples reported in the scientific and technical\nliterature referring to the Little Sugar Creek (at Charlotte, North Carolina), Red River of the North (North\nDakota/Minnesota), and the Assunpink Creek (at Trenton, New Jersey). The uncertainty of the results is\nassessed by complementing point estimates with confidence intervals (CIs) and emphasizing critical\naspects such as the subjectivity affecting the choice of the models� structure. Our results show that (1)\nnonstationary frequency analyses should not only be based on at-site time series but require additional\ninformation and detailed exploratory data analyses (EDA); (2) as nonstationary models imply that the\ntime-varying model structure holds true for the entire future design life period, an appropriate modeling\nstrategy requires that EDA identifies a well-defined deterministic mechanism leading the examined process;\n(3) when the model structure cannot be inferred in a deductive manner and nonstationary models\nare fitted by inductive inference, model structure introduces an additional source of uncertainty so that\nthe resulting nonstationary models can provide no practical enhancement of the credibility and accuracy\nof the predicted extreme quantiles, whereas possible model misspecification can easily lead to physically\ninconsistent results; (4) when the model structure is uncertain, stationary models and a suitable assessment\nof the uncertainty accounting for possible temporal persistence should be retained as more theoretically\ncoherent and reliable options for practical applications in real-world design and management\nproblems; (5) a clear understanding of the actual probabilistic meaning of stationary and nonstationary\nreturn periods and risk of failure is required for a correct risk assessment and communication....
Water is elixir of life. This paper focuses on the fluoride sources, its distribution and current status of fluoride occurrence in groundwater of mining area of Koderma. The factors which are mainly responsible for the occurrence of high fluorides in groundwater and fluoride associated diseases among the residents of the affected area were also analyzed. In the mining area of Koderma district, fluoride pollution in water is prevalent. The fluoride problem in the area is mainly geogenic. The solution of this problem is either look for the alternative sources of water supply or defluoridation....
Mathematical models have advancement to a point where they are considered to be an effective\ntool for simulating natural phenomena in coastal regions. This paper discusses the development of\nBay of Bengal Model (BoBM), updating of the model with the recent bathymetry and shore line of\nislands and coastline and upgrading from rectangular grid to finer size of mesh grids by using latest\nversion of MIKE21 FM modeling system. This model is very useful for the hydrodynamic study\nin the coastal region of Bangladesh. The article also presents the model set-up, boundary conditions\nand few calibration results of the model. The model applications clearly show the variation\nof the flow structure, their speed and direction separately for monsoon and dry season around the\nmodel area which covers the northern part of Bay of Bengal....
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