A method of model evaluation is presented which utilises a comparison with a benchmark model. The proposed benchmarking concept is one that can be applied to many hydrological models but, in this instance, is implemented in the context of an in-stream water quality model. The benchmark model is defined in such a way that it is easily implemented within the framework of the test model, i.e. the approach relies on two applications of the same model code rather than the application of two separate model codes. This is illustrated using two case studies from the UK, the Rivers Aire and Ouse, with the objective of simulating a water quality classification, general quality assessment (GQA), which is based on dissolved oxygen, biochemical oxygen demand and ammonium. Comparisons between the benchmark and test models are made based on GQA, as well as a step-wise assessment against the components required in its derivation. The benchmarking process yields a great deal of important information about the performance of the test model and raises issues about a priori definition of the assessment criteria.
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Catchment topography, channel incision, channel orientation (Webb and Zhang, 1997; Arscott et al., 2001; Poole and Berman, 2001) and riparian vegetation (Beschta and Taylor, 1988; Sinokrot and Stefan, 1993; Stott and Marks, 2000; Isaak and Hubert, 2001) all affect stream surface shading. This shading moderates high stream temperatures by reducing incident short-wave radiation. Shading can affect both the timing and magnitude of stream temperature changes. Where riparian vegetation provides channel shading, most notably at Site 1, short-wave radiation can be reflected or absorbed by the canopy, or transmitted through to the ground/stream (the latter is typically <20%, but can be as little as 5% of the incident short-wave flux; Oke, 1987). However, riparian vegetation also emits long- wave radiation toward the stream and reduces windiness (and consequently evaporative heat loss) which are likely to be important in reducing the nocturnal net radiative deficit compared with more open sites (Sinokrot and Stefan, 1993). These combined effects can result in substantially moderated thermal regimes in forested areas compared with sites with more open vegetation.
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The needs for the production of quality African catfish seed for stocking the fish ponds and natural water bodies has Abstract: This study was conducted to evaluate and compare the hatchability, survivability and growth performance of African catfish (Clarias garipinus) brood stock hatched and raised in different sources of water. The fishes in ratio 2 male to 1 female (1.2kg +/-0.02) were subjected to artificial propagation using Rain, Well, Stream and Borehole water. The latency period, number of eggs released, number of hatched fries, temperature, dissolved oxygen were recorded and hatchability, survivability were calculated. Latency and hatched period (10hrs and 48hrs) respectively were the same for all the treatments. The environmental temperature (25oC) was constants. However, number of egg released by the female fish in rain water (283,540.50) was significantly the highest (p>0.05) and least value of 54,520 eggs released was recorded for well water. However, highest number of hatched eggs (10,748) fries was recorded in borehole water which means fish hatched in bore hole had highest hatchability (8.99%) and least hatchability (3.78%) was observed in fish hatched with rainwater. In the same vein, Fish raised with bore hole also had highest survivability (91.13%). Although, Fish raised with stream water had the highest weight gain and least feed conversion ratio (103.90g and 0.28) respectively.
Hydrochemical research conducted in the years 2007–2010 comprised monitoring of the Włosanka stream waters and leachate waters from the municipal landfill in Kul- erzów in the Malopolskie province. 16 leachate samples were collected from the con- tainer taking into consideration the vertical stratification of the quality and samples of water from the Włosanka stream in measurement points situated before and after the landfill. Concentrations of metals: calcium, magnesium, sodium, potassium, iron, manganese and heavy metals: chromium, zinc, copper, cadmium, nickel and lead were determined in the leachates and the stream water. Analysis of the studied metals in the leachates revealed that only potassium concentration exceeded the highest admissible value which is the condition of introducing sewage to water bodies or to soil. Water along the investigated reach of the Włosanka stream, both above and below the mu- nicipal landfill was of quality class 1. The landfill had no significant effect on the stud- ied metal concentrations in the stream water – no statistically significant differences were registered between the concentrations of the studied metals (including heavy metals) either in the point above or below the landfill. However, statistical tests com- paring values of metal concentrations in the landfill leachates with the stream water revealed that the concentrations of 7 out of 12 tested metals were significantly higher in the leachates. Therefore, the landfill site monitoring should be continued, leachate waters should be collected in the container and supplied to the sewage treatment plant to prevent any threat to human life and health, or to the environment.
Because of establishment of the starting cover in the waterway bed the speed of stream gets diminished close to the bank and sediment testimony begins. With the expansion in volume of the residue store the standard stream heading of the waterway continuously makes tracks in an opposite direction from the bank and siltation territory gradually augments. As the water level retreats after surge the ranges encountering most astounding residue store seem first as a sand bar over the waterway water surface. Stream water keeps on streaming around these little sand bars. As the water subsides advance the following level of sediment store zones develop over the water surface. More siltation zones develop as the waterway water level keeps on subsiding until it achieves LWL. In this way, the diverse ground heights of bars in the waterway speak to various phases of their arrangement concerning time. The profile of this dynamic development of sand bars subsequently of actuated siltation can by implication be utilized to evaluate the adjustment in stream example of the waterway after establishment of the bank assurance works.
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Analysis of stream and groundwater chemistry has been used to assess the extent of groundwater interaction with surface waters (Neal et al., 1990; Hill and Neal, 1997; James et al., 2000; Cook et al., 2003; Malcolm et al., 2004; Rodgers et al., 2004). Such methods provide relatively quick and inexpensive descriptions of the spatial and temporal distribution of surface-groundwater interactions. For a naturally occurring substance to be used as an indicator of groundwater, its concentration in groundwater must be relatively consistent over both space and time, as well as significantly different from that of stream water. Initially, dissolved CO 2 is captured from the atmosphere by rainfall.
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Abstract: It is known that the evolution of technologies is greatly increasing in the modern day. The utilization of technologies in various sectors is very low. It is known that the renewable resources are utilized in various places for generating electricity. Renewable resources are used in various forms like Solar energy, wind energy etc. The major source for electricity is generated using Hydro power generator. The use of this hydro power generation is performed using water resource. During this, a mechanism is executed to extract power from the water resources. But due to the presence of aquatic life in dams, the creatures reduce the energy generation. In some cases, they damage the energy generating mechanism which gradually reduces the energy generation as well as requires manual word to repair the mechanism. So we propose this system which increases the energy generation and provides indication.
ABSTRACT: Akola is growing industrial city and also the pilgrim place in Vidharbha region of Maharashtra State, spreading on an area of 08 Sq.km. It is situated on the bank of river “Morna”. Approximately 54 MLD wastewater is flowing through the drainage system to the river water. Major part of the waste water is directly discharged into the river “Morna” and further many villages on the downstream side are using the river water for drinking and for irrigation purposes. The higher BOD, COD and other chemical and biological contents are polluting the river water and affecting quality of soil by lowering its fertility and health effect to people of Akola. It was intended to carry out the analysis of waste water of “River Morna”. The five sampling points were decided for collection of waste water from the “River Morna” and analysis is carried out and the results are discussed in the paper.
Unfortunately, our ability to assess alteration of natural stream flow patterns, and the ecosystem conse- quences, is hindered by the absence of stream flow data. California’s stream flow gauging network offers only a limited perspective on how much water is moving through our state’s rivers. In fact, it’s been estimated that 86% of California’s significant rivers and streams are poorly gauged and nearly half of the state’s historic gauges have been taken offline due to lack of funding (TNC 2018a). Of those gauges that are still in opera- tion, most are located on rivers that are highly modified by human activities and gauge records prior to impacts are limited. These limitations can be partially overcome with modeling approaches to predict the attributes of natural stream flow expected in the absence of hu- man influence. The predictions can then be compared to measured stream flow at gauging locations, or they can be used to estimate natural flow conditions in un- gauged streams.
Clean water is essential for ecosystems and for societies. The importance of water quality has been a top priority for environmental health, especially in aquatic ecosystems. In response to differences of climate, soils, geology, land use and land cover, natural water quality varies spatially and temporally. Pollution from point sources and nonpoint sources due to human activities are other disturbances to water quality (Carpenter et al., 1998). Most point source pollution is from industrial and sewage treatment plants. Nonpoint source pollution occurs when surface runoff, as a proxy for the energy associated with soil erosion and sediment transport, moves over land, picks up natural or human-made pollutions, and eventually flushes the pollution into water bodies (EPA, 1996; Kalkhoff et al., 2016). Surface runoff was recognized as the most critical energy factor for transports of sediment and sediment- attached nutrients such phosphorus and nitrogen according to empirical observations at field scales (Sharpley, 1982; Sharpley and Syers, 1979; Vadas et al., 2004; Williams, 1975). When the surface runoff generated from storm events combines with base flow, the water quality of stream flow can be disturbed by surface pollutants.
Turbidity is the degree to which a transparent liquid scatters light, usually a measure of the amount of suspended material in the liquid. Global Water's Turbidity Sensor is a highly accurate submersible instrument for in-situ environmental or process monitoring. Applications for the turbidity sensors include: water quality testing and management, river monitoring, stream measurement, reservoir water quality testing, groundwater testing, water and wastewater treatment, and effluent and industrial control.The turbidity sensor directs a focused beam into the monitored water. The light beam reflects off particles in the water, and the resultant light intensity is measured by the turbidity sensor's photodetector positioned at 90 degrees to the light beam. The light intensity detected by the turbidity sensor is directly proportional to the turbidity of the water. The turbidity sensors utilize a second light detector to correct for light intensity variations, color changes, and minor lens fouling. Since the turbidity sensor uses light to detect the water's turbidity ensure that the minimum amount of external light possible is exposed to the monitoring site.
50 We collected precipitation samples in bulk collectors distributed throughout the Coweeta basin. Collectors were constructed from 10 cm diameter polycarbonate rain gauges with a thin (5- 10 mm) layer of mineral oil inside to prevent evaporation (Michelsen et al., 2018). Water samples were collected using a clean, dry polyethylene syringe and tubing to extract water from beneath mineral oil. We transferred water from the syringe into a 20 mL high-density polyethylene (HDPE) vials sealed with a cone top cap. After sampling, precipitation collectors were cleaned and dried, and new mineral oil was added. Precipitation samples were collected every 1-4 weeks, depending on the total amount of precipitation. Total liquid water depth in the collector at the time of sampling was used to compute volume-weighted averages of precipitation oxygen and hydrogen isotopes for each week. All precipitation isotopes are reported in volume-weighted values. Frozen precipitation occurred infrequently and was not included in this study.
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development. Loading rates were increased from 2.3-kg/ha/day (1.5-gpm) early in the growing season to 5.4-kg/ha/day (3.5-gpm) to compensate for higher growing season evapotranspiration rates. Nitrogen mass reductions were fairly consistent throughout the study, with larger exports of total nitrogen observed in July and August of 2001. This could be associated with the die-off of plants in the upper portion (above the bulkhead) of the wetland. Although nitrogen uptake by plants was not a dominant mechanism of nitrogen removal, plants create an environment conducive for nitrogen removal in the soil matrix. Considering that the area above the bulkhead accounts for approximately 40% of the overall wetland surface area, the loss of plants in this section could have a significant impact on wetland performance. Total phosphorus export progressively increased to the point that inflow and outflow concentrations are equal, indicating that steady state assimilation of phosphorus may have been reached. Redox readings indicated the development of a strongly reduced soil environment, with values from March 2001- August 2001 averaging less than 0-mv. The pH of the water column conditions was favorable for the dissolution of the iron-phosphorus complex in the soil matrix, which is believed to be a major mechanism for phosphorus retention in constructed wetlands. These conditions limit phosphorus adsorption to soil particles, and might explain the recent large export of phosphorus from the wetland.
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The study shows that 30% of the respondents were aged between 30 and 39 years and the least being that of age bracket 15-19 years with only 2%. With gender, the study tried to get response from both parties with male at 48% and female at 45% of the total sample size. The study indicate that 52% of the population has lived in the sub catchment for more than seven years. This may indicate that the information provided is accurate. The study show that 57% of the population lack piped water. This situation puts pressure on the available water resources especially on the streams. Therefore to protect these stream, rainwater harvesting is inevitable because it is a potential source of adequate and reliable water supply, especially in rural areas, in particular, in less water endowed Kisii, where other water sources are not technically and/or economically feasible. Inadequately designed systems, in terms of storage capacity and catchment area, could only supply water for only a short period after the rainy season.
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rows. The ditch along the road was overfilled with washed-off soil and run over by water. The gully, formed below the road due to the concentrated runoff, was roughly 1 m wide and 0.5 m deep and it uncovered the deep subsoil (Figure 2). The transported material was deposited mainly on the wide meadow below the slope and smaller amounts entered into the stream (Figure 3). The platform of the solid sediment had almost a rhomboid shape with diagonals 75 m (in the runoff direction from the field to the channel) and 54 m (in the direc- tion parallel with the stream channel). The source microbasin above the deposit covered a total area Figure 2. Detail of middle part of the gully
Of the existing models, QUAL2E and QUAL2K have been widely used in water quality prediction and pollution management. The US Environmental Protection Agency released a series of QUAL models such as QUAL2E, QUAL2EUNCAS, QUAL2K, and QUAL2Kw. These models allow for the simulation of up to 15 parameters associated with water quality, in any combination chosen by the user (DO, BOD, temperature, algae as chlorophyll a, organic nitrogen as N, ammonia as N, nitrite as N, nitrate as N, organic phosphorus as P, dissolved phosphorus as P, coliform bacteria, one arbitrary nonconservative constituent solute, and three conservative constituent solutes).
average of AT, called lagged AT for simplicity in the rest of the paper, using different lags: 2, 3, 5, 7, 10 and 15 days. We first identified the lags that were maximizing the determina- tion coefficient R 2 between WT and lagged AT. The resulting R 2 exceed 0.90 (respectively 0.95) in 93% (59%) of the cases (Fig. 4). This demonstrates a strong linear relationship be- tween WT and lagged AT, and that lagged AT explains most of the variance of WT. The fraction of WT variance that is not explained by lagged AT (1 − R 2 ) can be related to the mea- surements uncertainties, or to unaccounted physical factors, such as discharge variability (Webb et al., 2003), groundwa- ter inflows, stream shading or impoundments (Erickson and Stefan, 2000), but this unexplained fraction is always small. Figure 4 also shows that the best R 2 increase with Strahler or- der, as do the corresponding lags (see also Table 1), and that the variability of the best R 2 is larger when resulting from small lags, thus at low Strahler orders. These results, which support the choice of the model proposed in Eq. (1), are very consistent with the convergence of WT toward equilibrium temperature as water flows downstream, which implies that the equilibrium temperature, approximated by lagged AT, ex- plains more and more of the variance of WT as water flows downstream, thus as Strahler order increases.
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Water-borne epidemics and health hazards in the aquatic environment are mainly due to improper management of water resources. Proper management of water resources has become the need of the hour as this would ultimately lead to a cleaner and healthier environment. In order to prevent the spread of water-borne infectious diseases, people should take adequate precautions. The water from Erai River gets contaminated due to water from Hindustan Lalpeth Open Cast Coal Mines. This water is not suitable for drinking purpose immediately.
from the hot tub circuit, which was distinguished by a lower value of both turbidity and UV254 ul- traviolet absorbance. During ultrafiltration, high values of the turbidity retention coefficient (about 99%) were obtained (which was presented by using a column chart). In contrast, a significant lowering of the membrane separation capacity in terms of ultraviolet absorbance, with the retention coefficient value ranging from 50 to 41%. During the filtration of backwash water with higher de- posit and suspended particulate contents (a higher turbidity value), a so-called secondary membrane might have formed, which could contribute to an increase in membrane separation capacity during filtration [Dudziak 2013]. In turn, the lower back- wash water turbidity value (the hot tub circuit) contributed to the membrane retaining its good transport capacity during ultrafiltration. The rela- tive permeability coefficients in the filtration cy- cle for the hot tube circuit backwash water were contained in the range of 0.97 (at 8% permeate stream recovery) ÷0.86 (at 50%). The nanofiltra- tion process in this case, too, was characterized by high contaminant retention coefficient values (Figure 2b). The aforementioned differences in physicochemical parameter values significantly affected the transport capacity of the membrane.
A novel chemosensor for the determination of trace amounts of cadmium (II) in water samples was proposed. OHPTU was used to determine cadmium (II) in very trace levels in the current study using absorption and fluorescence quenching studies. The activators and surfactants used in the study enhanced the sensitivity of the developed method. The Stern- Volmer plots indicate efficient fluorescence quenching and the statistical analysis proves that there is close concordance between the proposed and the standard AAS methods. Therefore, the method is simple, fairly selective with good sensitivity and was applied to determine cadmium in wide variety of samples. Application studies of the chemosensor to various other metals ions are in progress along with a portable hand held device for onsite monitoring.