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Sökning: L773:1058 3912 OR L773:1996 7918

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1.
  • Abbas, Nahlah, et al. (författare)
  • Assessment of climate change impacts on water resources of Khabour in Kurdistan , Iraq using SWAT model
  • 2016
  • Ingår i: Journal of Environmental Hydrology. - 1058-3912 .- 1996-7918. ; 24, s. 1-21
  • Tidskriftsartikel (refereegranskat)abstract
    • The Khabour River is one of five tributaries of Tigris River and the first river flows into Tigris River contributing to Tigris Flow by about 2 BCM at Zakho Station. The area of this catchment is 6,143 km2, of which 57% are located in Turkey and 43% in Iraq with a total length of 181 km. Khabour River is the main source of fresh water to Duhok City, one of the major cities of Kurdistan Region. Hydrometeorological data over the past several decades reveal that the catchment is experiencing increasing variability in precipitation and stream flow contributing to more severe droughts and floods presumably due to climate change. SWAT model was applied to capture the dynamics of the basin. The model was calibrated at Zakho station. The performance of the model was rather satisfactory; R2 and ENC were 0.5 and 0.51, respectively in calibration period. In validation process R2 and ENC were nearly consistent. In the next stage, six GCMs from CMIP3 namely, CGCM3.1/T47, CNRM-CM3, GFDL-CM2.1, IPSLCM4, MIROC3.2 (medres) and MRI CGCM2.3.2 were selected for climate change projections in the basin under a very high emissions scenario (A2), a medium emissions scenario (A1B) and a low emissions scenario (B1) for two future periods (2046-2064) and (2080-2100). All GCMs showed consistent increases in temperature and decreases in precipitation, and as expected, highest rate for A2 and lowest rate for B1. The projected temperatures and precipitation were input to the SWAT model to project water resources, and the model outputs were compared with the baseline period (1980-2010), the picture that emerged depicted deteriorating water resources variability.
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2.
  • Abbas, Nahla, et al. (författare)
  • Water resources problems of Iraq: Climate change adaptation and mitigation
  • 2018
  • Ingår i: Journal of Environmental Hydrology. - : International Association for Environmental Hydrology. - 1058-3912 .- 1996-7918. ; 26
  • Tidskriftsartikel (refereegranskat)abstract
    • Iraq is suffering from water scarcity, and future predictions indicate that it could get worse due to changing climate. Arguably, climate change is one of the greatest challenges onfronting this region it could have significant adverse effects on water resources and hence the environment and economy, particularly in the agricultural sector. This study considers possible adaptation and mitigation measures that could be undertaken in response to climate change. To overcome this problem,adaptation measures at farm and government level were conferred. Farm-level adaptation comprises adopting crop modification, soil conservation, irrigation, changing crop calendar and planting of trees. The government role is to ensure success of these adaptation measures. The government should get involved and support the farmers financially and technologically.
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3.
  • Abbas, Zainab Dekan, et al. (författare)
  • Locating Dam Sites For Water Harvesting : Case Study Of Najaf Province, Iraq
  • 2019
  • Ingår i: Journal of Environmental Hydrology. - Canada : The International Association of Environmental Hydrology. - 1058-3912 .- 1996-7918. ; 27, s. 1-8
  • Tidskriftsartikel (refereegranskat)abstract
    • The Middle East is considered as an arid area. Iraq was an exception due to the presence of the Tigris  and  Euphrates  Rivers. After  1970,  the  flow  of  these  rivers  started  to  decrease  due  to  climate change  and  building  of  dams  in  the  upper  parts  of  the  catchments  of  the  rivers.  Now,  Iraq  is experiencing  water  shortage  problems.  Rain  water  harvesting  will  definitely  minimize  the  effect  of water shortage problems. In this research an arid area was selected (al Najaf) to find out the best sites for water harvesting using GIS techniques. The good agreement between the results from a simple GIS model  and  observations  in  cases  such  as  al  Najaf  Sea  is  indicating  a  promising  future  for  GIS application  in  hydrological  modeling.  The  present  study  proposed  a  function  formula  of  estimating suitable dam site using existing geographic information map such as the digital elevation maps. It is expected that it will save time, cost and work force. Finally, through the contour map of the study area, the lowest three elevation values at the governorate level were observed (20, 40, 60m). Based on these values, three possibilities were suggested to select the dam sites.
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4.
  • Abdullah, Twana, et al. (författare)
  • Classification of groundwater based on irrigation water quality index and GIS in Halabja Saidsadiq basin, NE Iraq
  • 2016
  • Ingår i: Journal of Environmental Hydrology. - 1058-3912 .- 1996-7918. ; 24
  • Tidskriftsartikel (refereegranskat)abstract
    • Assessment of groundwater for irrigation purpose is proposed using the Irrigation Water Quality Index (IWQI) within the GIS environment. The model was applied to several aquifers in the study basin. Water samples were collected from thirty-nine sites from both water wells and springs from the dry season (September 2014) and the wet season (May 2015). Samples were tested chemically and physically for several variables: EC, Ca+2, Mg+2, Cl-, Na+ and HCO3- and SAR. The accuracy and precision methods were applied to find out the uncertainty of the chemical analysis results and its validity of application for the geochemical interpretations. Based on the spatial distribution of IWQI, the groundwater quality of HSB classified into several classes of both dry and wet seasons in terms of its restrictions on irrigation purposes. The classes include, Severe Restriction (SR), High Restriction (HR) and Moderate Restriction (MR). The coverage areas of all three classes are 1.4%, 52.4% and 46.2% for the dry season and 0.7%, 83.3% and16% for wet seasons respectively. The considerable variations in all these classes have been noted from dry to wet seasons, this might be related to increasing the aquifer recharges from precipitation and decreasing the aquifer discharges by the consumers in the wet season. Then the model was validated based on the relation between the aquifer recharge and spatial distribution of IWQI, the result of this validation confirmed the outcome of this study.
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5.
  • Abdullah, Twana O., et al. (författare)
  • Effect of Agricultural activities on Groundwater Vulnerability: Case Study of Halabja Saidsadiq Basin, Iraq
  • 2015
  • Ingår i: Journal of Environmental Hydrology. - 1058-3912 .- 1996-7918. ; 23:10
  • Tidskriftsartikel (refereegranskat)abstract
    • Groundwater is one of the main sources of water in Halabja-Saidsadiq Basin of northeast Iraq. It covers an area of 1278 square kilometers with population of about 190,727.In this study, the standard DRASTIC method has been applied to generate a map of groundwater pollution vulnerability of the basin. In addition, two different scenes of landsat Thematic Mapper (TM) were used with the aid of ERDAS IMAGINE software and the GIS technique to prepare digital image classification of the study basin. Supervised classification for level I of USGS was conducted with band combination RGB/742 to prepare The Land Use and Land Cover (LULC) map. The LULC map illustrates that only five classes of land use can be identified these are: barren, agricultural, vegetation, urban and wet land or water body. The LULC map converted to LULC index map. This index map has an additional parameter added to the standard DRASTIC model to map the modified DRASTIC vulnerability in the study basin. Nitrate concentration analysis was selected and added as a pollution indicator to validate this modification. In this study, the nitrate concentration between two different seasons (dry and wet) was analyzed from (30) water wells. The standard vulnerability map of the studied basin classified the basin into four vulnerability index zones: very low (34%), low (13%), moderate (48%) and high (5%). While the combined modification classified the area into five classes: very low (1.17%), low (36.82%), moderate (17.57%), high (43.42%) and very high (1.02%). The results s that the modified DRASTIC model was dramatically superior to the standard model; therefore, the most appropriate method to apply is the combination of standard DRASTIC model with LULC index map. This conclusion is based on the results of nitrate content, as its concentration in the dry season is much lower than in the wet season.
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6.
  • Al-Ani, Ibrahim Abdulrazak, et al. (författare)
  • Multi criteria decision making to optimize the best runoff control measures for the Haditha Dam Reservoir, Iraq
  • 2020
  • Ingår i: Journal of Environmental Hydrology. - : International Association for Environmental Hydrology. - 1058-3912 .- 1996-7918. ; 28
  • Tidskriftsartikel (refereegranskat)abstract
    • In Iraq, the two dominating surface water sources are Tigris and Euphrates Rivers in which some dams constructed on both of them forming reservoirs. The Haditha Dam reservoir is one of the most essential sources of drinking, irrigation, flood control and hydropower generation in Anbar State, Western Iraq. Besides, the reservoir is a unique habitat with a wide spectrum of biodiversity. The objective of this study is to investigate and monitor the water quality in Haditha Dam reservoir and introduce Multi Criteria Analysis (MCA) as a means to highlight the best runoff control measures depending on selected criteria and criteria weights. Experts were interviewed for the selection of criteria and for the assignment of the weight factor and scores. Four criteria from three categories such as technical, economic and environmental aspects were selected. Results from this study indicated that a the difference in TSS and Turbidity between the dry and wet seasons necessitates the installation of runoff control measures. It was found that the soil binders, sediment basin and diversion channel are the best alternatives for controlling erosion, sediment and drainage respectively. The sensitivity analysis showed very strong decisions made by the experts for the technical, economic and environmental criteria.
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7.
  • Al-Ani, Thair, et al. (författare)
  • Trace elements in water and sediments of the Tigris river, Baghdad City, Iraq
  • 2014
  • Ingår i: Journal of Environmental Hydrology. - 1058-3912 .- 1996-7918. ; 22
  • Tidskriftsartikel (refereegranskat)abstract
    • Industrial, agricultural and rural activities may result in pollution of watercourses with elevated trace metal concentrations and implications for water supply and ecosystem functioning. The concentration of the trace metals Fe, Mn, Zn, Co, Pb, Cu, and Cd in the water and clay fractions (<2μm) of the bank sediments of River Tigris in Baghdad city were determined. Dissolved trace metals concentrations were far below the upper permissible limits during 2012-2013. There was no consistent pattern between element concentrations and river discharge. Seasonal interrelations between water and sediments were most obvious for Fe that decreased in both environments with rising flows during autumn. Although independent of discharge, Mn in water and sediments often followed each other at all stations. Zinc, however, increased in the sediments and decreased in the water with discharge. The clay fractions were slightly to strongly enriched in trace metals with the gradient Co > Fe > Zn > Mn > Cu suggesting absorption of the metals on sediment substrate.
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8.
  • Al-Ansari, Nadhir, et al. (författare)
  • Effect of treated wastewater irrigation on vegetables
  • 2013
  • Ingår i: Journal of Environmental Hydrology. - 1058-3912 .- 1996-7918. ; 21
  • Tidskriftsartikel (refereegranskat)abstract
    • Treated waste water is normally used for irrigation purposes in countries suffering from water shortages to narrow the gap between supply and demand. The concept behind this is to save water consumed for agricultural activities, which consumes most of the water, for municipal and industrial uses. The Alsukhna area in Jordan is used to grow vegetables which are irrigated by treated wastewater. Surface and groundwater samples from the Zarqa region were analyzed for their major cations, anions and heavy metals. The impact of the treated waste water on the chemical components of vegetables was studied using Zn, Mn, Fe, Pb and Ni in sweet and hot pepper, tomato, cauliflower, cabbage, squash, cucumber and eggplant which were compared with similar vegetables irrigated by natural unpolluted water from the Mafraq region. The four metals, namely Zn, Fe, Pb, and Ni, had concentrations higher than in the reference vegetables by 3423%, 155%, 397%, 2949% and 289%, 187%, 211%, 214% fortomato and cauliflower, respectively. Sweet pepper was mainly influenced by an increased content of Fe, which was almost 180% higher than that in sweet pepper from the Mafraq region. Hot pepper had highly elevated concentrations of Ni (6980%) and Zn (419%), while squash demonstrated high Zn (207%) and Pb (666%). When all the heavy metals are considered, the most affected vegetable is the hot pepper with an average percent of heavy metals accumulation of 1559% while the least effected is cabbage at 116%.
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9.
  • Al-Ansari, Nadhir, et al. (författare)
  • Sedimentation in the Mosul reservoir of northern Iraq
  • 2013
  • Ingår i: Journal of Environmental Hydrology. - 1058-3912 .- 1996-7918. ; 21:7, s. 1-10
  • Tidskriftsartikel (refereegranskat)abstract
    • Mosul Dam is one of the biggest hydraulic structures in Iraq. It was constructed in 1986 on the Tigris River in the north of Iraq for multiple purposes: irrigation, flood control and power generation. The initial storage capacity and water surface area of its reservoir reaches 11.11 km3 and 380 km2 respectively at the maximum operation level 330 m a.s.l. The dam was operated in 1986. Blockage of the intakes of the pump station for North Al-Jazira Irrigation Project in Mosul Dam reservoir has highlighted the importance of sedimentation problems within the reservoir. A total of 56 samples were collected from the bottom of Mosul reservoir covering most of the reservoir area. The results of the analysis of these samples revealed that they were composed of gravel (3.8%), sand (15%), silt (55.5%) and clay (25.7%). The distribution of these sediments indicates that the silt portion represents the highest 77% of the bottom sediments of this reservoir followed by clay (13.5%) and then sand (9.5%). However, sand percentages are the highest in the northern zone of the reservoir where the River Tigris enters the reservoir and decreases gradually toward the dam site. In the meantime, silt percentage decreases toward the dam site while the finer fraction (i.e. clay) increases. Statistically, the average median and mean sizes of the sediments are 2.81 phi (0.142 mm) and 6.1 phi (0.0146 mm) respectively. In addition, the sediments are poorly sorted, nearly symmetrical in skewness and leptokurtic, very leptokurtic, to mesocratic. Finally, it is believed that the geometry and hydrodynamics of the Mosul reservoir, the location of the River Tigris entrance together with the side tributary valleys have played the most important role in the sediments distribution and their characteristics.
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10.
  • Al Dahaan, Saad A.M., et al. (författare)
  • Salinity functions for groundwater at Safwan, South Iraq
  • 2019
  • Ingår i: Journal of Environmental Hydrology. - Canada : International Association for Environmental Hydrology. - 1058-3912 .- 1996-7918. ; 27:7, s. 1-11
  • Tidskriftsartikel (refereegranskat)abstract
    • Function type between electrical conductivity and total dissolved solids is polynomial and the exponential which are taken according to the water quality classification for irrigation. These functions relate the EC in ds/m to the salinity in term of part per million or to the half salinity in equivalent per million directly or in form of logarithmic transformation. A statistical test for best fit is considered for the selection of the type of a representative function. The irrigation salinity classification is taken as index of grouping extended to moderately sensitive vegetable crop tomato as salinity tolerance rating up to 15 ds/m groundwater salinity used for irrigation at Safwan area of arid climate. All fitted type of functions is programmed within a flow model computer of basic language by which the output from of both methods is an average final value. Thus the coast of analysis is reduced. This type of functions is standard for groundwater and so designed to involve the water type. The involved parameter for Safwan area is 0.5 for more than 5 ds/m in case of ppm half total and it is 1.3 for less than 5ds/m salinity, or using the direct model.
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11.
  • al-Dahan, Saadi, et al. (författare)
  • Hydrochemistry of springs, Najaf area, Iraq
  • 2015
  • Ingår i: Journal of Environmental Hydrology. - 1058-3912 .- 1996-7918. ; 23
  • Tidskriftsartikel (refereegranskat)abstract
    • Springs exist in southwestern Iraq at Najaf area in southwestern desert (latitude 31º 00 ̄ – 32º 15 ̄ and longitude 43º 30 ̄ – 44º 30 ̄). Two aquifers exist in the area. The first is composed of recent deposits while the second aquifer is of Miocene deposits. The latter is important because it contains huge quantities of groundwater. Water of these springs is slightly brackish and very hard. The predominant salt in the water of these springs is magnesium sulfate (MgSO4) and sodium chloride (NaCl). The water type is sulfate. Most of water springs (70%) are of marine water origin, while the minority (30%) are of continental water origin.
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12.
  • Al-Haidarey, Mohammed J. S. A., et al. (författare)
  • The Trophic State Index of Bahr Al-Najaf Depression reservoir, Iraq
  • 2016
  • Ingår i: Journal of Environmental Hydrology. - 1058-3912 .- 1996-7918. ; 24, s. 1-10
  • Tidskriftsartikel (refereegranskat)abstract
    • Bahr Al-Najaf Depression Reservoir (BNDR) is located 5 kilometers south-southwest of Najaf city in central Iraq. It covers an area of approximately 360 square kilometers. Carlson’s Trophic State Index (CTSI) was applied to the BNDR. To do so, Chlorophyll (A), total phosphorus (TP), Secchi disc depth Transparency (SD) and some physiochemical parameters were measured. The mean value of Chl-a was 1,06 (±1,33), the maximum and minimum values of TSI based on total Chl-a were recorded during summer and spring respectively. The classification of trophic state using TSI (TP) and TSI (SD) was closed, but by using TSI (Chl-a) it was much higher, the value of TSI (Chl-a) > TSI (TP) >TSI (SD), the CTSI value of BNDR was between 35.11-71.33 (r2 = -27, 53), the highest value of CTSI was in summer while the lowest values were during winter, the average of physiochemical parameters (±standard deviation) were: 26,5 (±1,42), 7,6 (±0,88), 0,1 (±0,16), 71 (±16,57), 10100 (±5591), 1,55 (±2,26), 53350 (±24143), 243299 (±358773), 30752 (±44649), 20 (±13), 2499 (±1819), 2659 (±2561), 0,22 (±0,02), 0,32 (±0,06) for temperature, pH, DO, Ec, HCO- 3, TN, TH, Cl- SO= 4 , TOC, Na+, K+, Fe+, and Mn+ respectively. According to CTSI, BNDR can be classified as eutrophic. CTSI results were very close to those of lakes Sawa and Al-Razzazah, while there were some slight differences when compared with Al-Habbanayh and Derbandikhan lakes, where the level of trophic index was decreasing (56, and 52 for Al-Habbanayh lake and Derbandikhan lake respectively).
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13.
  • Alanbari, Mohammad, et al. (författare)
  • Selecting sustainability indicators of urban water systems: Case study of al-Hilla city, Iraq
  • 2015
  • Ingår i: Journal of Environmental Hydrology. - 1058-3912 .- 1996-7918. ; 23
  • Tidskriftsartikel (refereegranskat)abstract
    • The present study used environmental criteria to appraise the sustainability of the urban water system(UWS) of Al-Hilla city, Iraq. The study focused on the assessment of the environmental impact anddamage to the urban water system. Environmental criteria of sustainability included a number ofindicators. These indicators were selected using tools of sustainability analysis, where life cycleassessment (LCA) was used to select and analyze the environmental indicators by applyingSimaPro7.1.8. LCA. The results for urban water system in Al-Hilla city showed that water treatmentplants (WTPs) and distribution network were most sustainable compared with sewerage network andwaste water treatment plants (WWTP). WTPs impact and damage on the environment and distributionnetwork was 4 and 11.5 points respectively, while Al-Hilla WWTP and sewerage network was 41 and291 points respectively, for delivery of one cubic meter of potable water at the point of consumption ortreatment of one cubic meter of wastewater. In addition, the study showed that most of the effects weredue to electricity consumption, pumping raw water and clean water, chemical use (such as chlorine),pipes used in water distribution and sewage collection networks, and diesel used for plant operation.
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14.
  • AlJawad, Sadeq B., et al. (författare)
  • Evaluation of Storm Runoff in Wadi Hauran, Western Iraq
  • 2017
  • Ingår i: Journal of Environmental Hydrology. - : International Association for Environmental Hydrology. - 1058-3912 .- 1996-7918. ; 25
  • Tidskriftsartikel (refereegranskat)abstract
    • Arid and semi arid regions are characterized by low frequency monthly rainfall events and high evaporation during the remaining dry days. Utilizing monthly rainfall means for water balance calculation risks a high error margin. Even when daily rainfall analysis methods are used to evaluate the resulting runoff in a valley course, errors may still be committed when wrong values are assigned to important field elements such as soil cover type, vegetation and land use. Accordingly and when the Soil Conservation Service method (SCS) is applied, single storm rainfall and validation of the estimated Curve Number (CN) value using valley flow measurements is necessary. The evaluation of annual runoff volume in a major valley in the Western Iraqi desert using the SCS method applied to single rainfall storm events and validated by actual historical runoff measurements has revealed that Wadi Hauran would exhibit no runoff flow in one year out of three and that runoff may exceed 69 mm depth in a single water year but the average depth for those years with runoff events is only 11.1 mmwhich amounts to about 64 Mm3 at a location in the center of its catchment area.Journal
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15.
  • Ezz-Aldeen, Mohammad, et al. (författare)
  • Estimating life span of rainwater harvesting reservoirs in Sinjar area, Iraq
  • 2016
  • Ingår i: Journal of Environmental Hydrology. - 1058-3912 .- 1996-7918. ; 24, s. 1-10
  • Tidskriftsartikel (refereegranskat)abstract
    • Due to water shortage in different places in Iraq especially for areas far away from main river flows (Tigris and Euphrates Rivers), rainwater harvesting reservoirs were suggested previously to store runoff water for different water supply purposes. In this study, the Soil and Water Assessment Tool (SWAT) was applied to estimate the sediment load yields from each watershed of a selected reservoir to estimate probable life based on resultant sediment load and trap efficiency. The results indicates that the annual sediment load varied from 40*103 to 4.4*103 ton depending on watershed area and other effective properties, while the sediment yield per unit area were ranged between 9.5 to 20 ton/km2. The estimated trap efficiency based on annual inflow and reservoir storage capacity were varied from a minimum of 96.5 to 100% due to high reservoir capacity in comparison to annual inflow. The resultant probable life of the reservoirs was greater than 100 years, indicating that the reservoir can economically accepted.
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16.
  • Hussain, Hussain Musa, et al. (författare)
  • Evaluation and Mapping Groundwater Suitability for Irrigation Using GIS in Najaf Governorate, Iraq
  • 2014
  • Ingår i: Journal of Environmental Hydrology. - 1058-3912 .- 1996-7918. ; 22
  • Tidskriftsartikel (refereegranskat)abstract
    • Irrigation Water Quality Index (IWQI) for groundwater within the Geographic Information System(GIS) environment is proposed so that it can be used in assessing the groundwater vulnerability. Themodel was applied to the Damman aquifer in the western part of Iraq. Thirty nine sites were chosen forthe investigation of the Damman aquifer. Triplicate ground water samples were collected from eachsite (during wet and dry seasons of 2013). Variables tested in each sample include: pH, EC, totalhardness Ca+2, Mg+2, Cl-, Na+ and SAR. The final water quality map constructed for the aquifershowed that there are three major regions. The first is in the northeastern part of the area while thesecond region is confined to the southeastern part. Finally, the third region extended along the westernpart of the study area. When this map was converted according to the suggested model, it showed thatthe water quality of the Damman aquifer is marginal for use for agriculture purposes.Journal
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17.
  • Issa, Issa E., et al. (författare)
  • Mosul Dam Resorvoir Sedimentation Characteristics, Iraq
  • 2014
  • Ingår i: Journal of Environmental Hydrology. - 1058-3912 .- 1996-7918. ; 22
  • Tidskriftsartikel (refereegranskat)abstract
    • Sediment transported by rivers and finally deposited in reservoirs directly affects dam performanceand causes a reduction in their storage capacity and hence operating efficiency. In this study, thesedimentation characteristics of Mosul dam reservoir have been evaluated using two topographic mapsof the reservoir area at different times (1986 and 2011) via Arc/GIS software. The dam is located on theTigris River in the northern part of Iraq and started operating in 1986. The water surface area of itsreservoir is 380 km2 with a designed storage capacity of 11.11 km3 at a maximum operating level (330m a.s.l). The results showed that the annual sediment deposition rate is 45.72 × 106 m3 year-1 of which23.2 × 106 and 22.52 × 106 m3 year-1 are in the dead storage and live storage zones respectively. As aconsequence, the live and dead storage zones lost 6.9% and 19.66% respectively of their storagecapacity during the 25 year of operation of the dam. The water-spread area (water surface area) of thereservoir at dead storage level (300 m a.s.l) was reduced annually by about 1.34 km2. Furthermore,the stage-storage capacity curves for future periods (prediction curves) were assessed and comparedwith adopted prediction curves using 2011 bathymetric survey data.
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18.
  • Loffill, Ed, et al. (författare)
  • Aerated CoUFs - A pilot scale study into the impacts of changing variables on nitrification performance
  • 2013
  • Ingår i: Journal of Environmental Hydrology. - 1058-3912 .- 1996-7918. ; 21
  • Tidskriftsartikel (refereegranskat)abstract
    • This paper describes the findings of a long term study of the nitrification performance of apurpose built, large-scale, pilot plant consisting of two mirrored, aerated, continuouslyoperated upflow filters (ACoUFs) operating under realistic conditions. The effect oftemperature, liquid flow rate, aeration rate and media types on the performance of each ofthese filters is reported. After a start-up period of 2-3 weeks each plant performed consistentlyand the performance, expressed as a concentration change between influent and effluent, wasfound to depend directly on temperature and aeration but inversely on flow rate, with littleinteraction between the variables. The introduction of these aerated CoUF variants can havea considerable role to play in increasing effluent quality.
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19.
  • Osman, Yasin, et al. (författare)
  • Climate Change and Future Precipitation in Arid Environment of Middle East : Case study of Iraq
  • 2017
  • Ingår i: Journal of Environmental Hydrology. - : International Association for Environmental Hydrology. - 1058-3912 .- 1996-7918. ; 25, s. 1-18
  • Tidskriftsartikel (refereegranskat)abstract
    • In this paper impact of climate change on precipitation in the arid environment of Iraq is examined.  LARS-WG weather generator was applied to 5 representative regions to model current and future precipitation under climate change. Seven Global Climate Models (GCMs) have been employed to account for any uncertainty on future projection for three selected periods, 2011-2030, 2046-2065 and 2080-2099. Performance of LARS-WG in each site was first evaluated using the Kolmogorov-Smirnov statistical test for fitting wet/dry days in each site, as well as comparison of the mean and standard deviation between the observed and simulated precipitation. The developed LARS-WG models were found to perform well and skilful in simulating precipitation in the arid regions of Iraq as evidenced by the tests carried and the comparison made. The precipitation models were then used to obtain future projections for precipitation using the IPCC scenario SRES A2. Future precipitation results show that most of the Iraq regions are projected to suffer a reduction in annual mean precipitation, especially by the end of the 21st century, while on a seasonal basis most of the regions are anticipated to be wetter in autumn and winter. 
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20.
  • Shammas, Mahaad I., et al. (författare)
  • Sea water intrusion in the Salalah plain aquifer, Oman
  • 2007
  • Ingår i: Journal of Environmental Hydrology. - 1058-3912 .- 1996-7918. ; 15, s. 1-14
  • Tidskriftsartikel (refereegranskat)abstract
    • Salalah is situated on a fresh water aquifer that is replenished during the annual monsoon season with an average vertical precipitation (rainfall) of 245 mm/yr in Jabal AlQara and 104 mm/yr in the Salalah plain. The aquifer is the only source of water for Salalah city. A rainfall and mist precipitation in the Jabal AlQara recharges theplain with significant renewable fresh groundwater resources that have allowed agricultural and industrial development to occur. In Salalah city where groundwater has been used extensively since the early 1980s for agricultural, industrial and municipal purposes, the groundwater resource has been withdrawn from the aquifer more rapidly than it can be replenished by natural recharge. In turn, the heavy withdrawal of large quantities of the groundwater from the aquifer has lead to intrusion of sea water. Agricultural activities usually utilize over 70% of the groundwater. In order to investigate the salinity intrusion and nitrate pollution, the study area was divided into four strips on the basis of land use plans in the area. Water samples were collected from 18 water wells. Chemical analysis of basic ions and pollution parameters in natural waters was carried out. The electrical conductivity, chloride and nitrate concentrations were highest in the agricultural and residential strips, and Garziz grass farm. The present status of groundwater quality in most of the agricultural and residential strips does not meet drinking water standards. The study suggests an approach to protect the groundwater in the Salalah plain aquifer from further encroachment, by artificial recharge with reclaimed water, preferably along the Salalah coastal agricultural strip. This scheme can also be applied to other regions with similar conditions.
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