Presence and Dispersion of Organic and Inorganic Contaminants in Groundwater

This paper offers an extensive examination of studies published in the recent past and highlights the documented issues surrounding groundwater pollution, its sources, and distribution worldwide. The depletion of groundwater resources and the deteriorating overall quality present a significant cause for concern, particularly as a large human population relies on groundwater as a drinking water source. The review focuses on various factors contributing to groundwater pollution, including anthropogenic activities, hydro climatological influences, and natural processes. Special attention is given to organic contaminants such as pesticides, herbicides, and emerging pollutants, which have been found to have a substantial impact on groundwater quality. Additionally, the review covers pollution caused by inorganic pollutants like arsenic and other heavy metals, with a particular emphasis on regions experiencing a higher incidence of these contaminants in groundwater. Furthermore, the paper includes a compilation of studies that highlight the increased occurrence of waterborne illnesses resulting from fecal and microbial contamination, often caused by inadequate sanitary practices. To provide a comprehensive understanding of the global groundwater pollution problem, the review also encompasses an examination of contaminants like fluoride and nitrate

Improved Integrated Risk Assessment of Geogenic Arsenic: Exposure and Attributable Health Risks

The linkage between arsenic contaminated water and increased cancer risk is well recognized. The potential health risk posed by separate inorganic and organic arsenic species through combined exposure to arsenic contaminated water and staple foods is not well understood though. Therefore, this research aims to improve arsenic risk assessment by investigating the primary exposure sources, pathways, metabolism and response indicators in an integrated manner. The population based water and food consumption pattern characterised by this research was used to validate the cancer risk modelling which demonstrated that using water or food intake values from the developed world may not represent cancer risks to the specific population in question. Integrating this characterisation with arsenic species provided several key insights. Arsenate was identified as the main species in the ground water aquifers of five villages whilst the predominance of arsenite and its co-existence with arsenate in one village indicated variations in aquifer redox conditions. Wheat cultivated with arsenic-rich irrigation water proved to be an alternate exposure pathway of inorganic arsenic. The species specific probabilistic cancer and non-cancer risks were found to be higher for arsenite followed by arsenate, whilst no risk was found for dimethylarsinic acid of dietary origin. The comparative impact of various reference doses on chronic health risk substantiated that children are at higher vulnerability, whilst using population based exposure characteristics of this study population and relative risk estimates from southwest Taiwan, showed females to be at higher risk of life time bladder and lung cancer due to inorganic arsenic. No risk was associated with low doses of arsenic. Total ingested arsenic from water or food under the effect of certain potential modifiers was a significant predictor of arsenic species in human biomarkers and proved toenail to be a comparatively effective biomarker. At low arsenic levels in water, food associated total arsenic was a better predictor of urinary metabolites. The total arsenic intake from water and urinary metabolites under the effect of labour jobs strongly predicted the increased risk of arsenical skin lesions. Probabilistic risk modelling indicated that persons with skin lesions were at higher risk of transformation of skin lesions into skin cancer, also evidenced with their lower methylation capability. Overall, this thesis provides evidence that species based risk assessment requires a greater understanding of exposure matrix, toxicological thresholds and metabolic reactions from ingestion to potential endpoints. This study has provided a baseline of inorganic arsenic for risk management to set public health water supply goals and to minimize the daily consumption of cooked rice for compliance with the safe arsenic limit. The findings are suitable to support future regulatory processes for species based arsenic limits in water together with staple foods

A historical appraisal of the water dispute in the Indus Basin, 1947-1960

This study proves that human needs are inseparable by historical factors. This appraisal is an effort to re-evaluate complex and perennial saga of Indus Basin by apportioning "history at the heart of a geo-political conflict". This thesis examines conflicting mechanism of territorial distribution that arose after partition of India on distribution of water resources. There was a wide gap between both countries regarding the suggestions on water sharing of Indus Basin. This exploration attempts to comprehend the gap between disputants and dispute by analyzing the role of World Bank in combination of financial issues. In reference to United States policy towards containment of communism laid interest in South Asia that engaged World Bank to intervene through achievement of Indus Water Treaty. This historical research uses qualitative approach, highly dependent on primary data collected from The British National Archives and The British Library, both in the United Kingdom, sources also gathered in Islamabad from National Documentation Wing, National Institute of Historical and Cultural Research, Water Management Departments and Punjab Archives, Lahore along with semi structured interviews conducted from high official of Governmental Water Institute and water experts. The finding shows that Permanent Indus Commission from both Pakistan and India should be strengthened to improve confidence building measures in order to avoid differences and disputes in Indus Basin. It significantly described the vast political and geographical impacts of water dispute in Indus Basin with impacts, recommendations and current advancements in India and Pakistan. Another outcome of this research comprehends water game of South Asia by developing economic ties among contributors of Indus Basin through diplomatic talks. This research also suggests new dimension to mechanism of dispute settlement through historical perspective in respect of adjustment towards environmental changes and water administration along with improving geopolitical interests of countries lying in Indus Basin

USCID Fourth international conference on irrigation and drainage

Presented at the Role of irrigation and drainage in a sustainable future: USCID fourth international conference on irrigation and drainage on October 3-6, 2007 in Sacramento, California.Includes bibliographical references.Integrated regional water management -- Change of irrigation water quantity according to farm mechanization and land consolidation in Korea -- Local stakeholders participation for small scale water resources management in Bangladesh -- Water user participation in Egypt -- The man swimming against the stream knows the strength of it -- Roles and issues of Water Users' Associations for Sustainable Irrigation and Drainage in the Kyrgyz Republic and Uzbekistan in Central Asia -- Chartered Water User Associations of Afghanistan -- Updated procedures for calculating state-wide consumptive use in Idaho -- Measuring and estimating open water evaporation in Elephant Butte Reservoir in New Mexico -- Evapotranspiration of deficit irrigated sorghum and winter wheat -- Evaluation of a two-layer model to estimate actual evapotranspiration for vineyards -- Estimating pecan water use through remote sensing in Lower Rio Grande -- Estimating crop water use from remotely sensed NDVI, crop models, and reference ET -- Alfalfa production using saline drainage water -- Performance evaluation of subsurface drainage system under unsteady state flow conditions in coastal saline soils of Andhrapradesh, India -- Management strategies for the reuse of wastewater in Jordan -- Providing recycled water for crop irrigation and other uses in Gilroy, California -- Oakdale Irrigation District Water Resources Plan -- Use of information technology to support integrated water resources management implementation -- Decision-support systems for efficient irrigation in the Middle Rio Grande -- Salt management -- Ghazi Barotha Project on Indus River in Pakistan -- Field tests of OSIRI -- Water requirements, irrigation evaluation and efficiency in Tenerife's crops (Canary Islands, Spain) -- Using wireless technology to reduce water use in rice production -- Variability of crop coefficients in space and time -- Assessing the implementation of integrated water management approach in closed basins -- New strategies of donors in the irrigation sector of Africa -- Holistic perspective for investments in agricultural drainage in Egypt -- Mapping system and services for canal operation techniques -- An open channel network modernization with automated structures -- Canal control alternatives in the irrigation district 'Sector BXII del Bajo Guadalquivir,' Spain -- Hydrodynamic behavior of a canal network under simultaneous supply and demand based operations -- Simulation on the effect of microtopography spatial variability on basin irrigation performance -- Drip irrigation as a sustainable practice under saline shallow ground water conditions -- Water retention, compaction and bean yield in different soil managements under a center pivot system -- Precision mechanical move irrigation for smallholding farmers -- Wild flood to graded border irrigation for water and energy conservation in the Klamath basin -- A method describing precise water application intensity under a CPIS from a limited number of measurements -- An irrigation sustainability assessment framework for reporting across the environmental-economic-social spectrum -- Planning for future irrigation landscapes -- One size does not fit all -- Water information networks -- Improving water use efficiency -- Irrigation system modernization in the Middle Rio Grande Valley -- Relationship of operation stability and automatic operation control methods of open canal -- Responsive strategies of agricultural water sector in Taiwan -- Effect of network water distribution schedule and different on-farm water management practices on sugarbeet water use efficiency -- Variable Frequency Drive (VFD) considerations for irrigation -- Accuracy of radar water level measurements -- Transition submergence and hysteresis effects in three-foot Cutthroat flumes -- Practical irrigation flow measurement and control -- Linear anionic PAM as a canal water seepage reducing technology -- In-situ non-destructive monitoring of water flow in damaged agricultural pipeline by AE -- Reoptimizing global irrigation systems to restore floodplain ecosystems and human livelihoods -- Water management technologies for sustainable agriculture in Kenya -- Impacts of changing rice irrigation practices on the shallow aquifer of Nasunogahara basin, Japan -- Drought protection from an in-lieu groundwater banking program -- Development of agricultural drought evaluation system in Korea -- Bean yield and root development in different soil managements under a center pivot system -- Can frost damage impact water demand for crop production in the future? -- Real time water delivery management and planning in irrigation and drainage networks -- Growth response of palm trees to the frequency of irrigation by bubblers in Khuzestan, Iran -- Application of Backpropagation Neural Network to estimate evapotranspiration for ChiaNan irrigated area, Taiwan -- Increasing water and fertilizer use efficiency through rain gun sprinkler irrigation in sugar cane agriculture

USCID fourth international conference

Presented at the Role of irrigation and drainage in a sustainable future: USCID fourth international conference on irrigation and drainage on October 3-6, 2007 in Sacramento, California.Salt management is a critical component of irrigated agriculture in arid regions. Successful crop production cannot be sustained without maintaining an acceptable level of salinity in the root zone. This requires drainage and a location to dispose drainage water, particularly, the salts it contains, which degrade the quality of receiving water bodies. Despite the need to generate drainage water to sustain productivity, many irrigation schemes have been designed and constructed with insufficient attention to drainage, to appropriate re-use or disposal of saline drainage water, and to salt disposal in general. To control the negative effects of drainage water disposal, state and federal agencies in several countries now are placing regulations on the discharge of saline drainage water into rivers. As a result, many farmers have implemented irrigation and crop management practices that reduce drainage volumes. Farmers and technical specialists also are examining water treatment schemes to remove salt or dispose of saline drainage water in evaporation basins or in underlying groundwater. We propose that the responsibility for salt management be combined with the irrigation rights of farmers. This approach will focus farmers' attention on salt management and motivate water delivery agencies and farmers to seek efficient methods for reducing the amount of salt needing disposal and to determine methods of disposing salt in ways that are environmentally acceptable

USCID fourth international conference

Presented at the Role of irrigation and drainage in a sustainable future: USCID fourth international conference on irrigation and drainage on October 3-6, 2007 in Sacramento, California.Includes bibliographical references.The two-layer model of Shuttlerworth and Wallace (SW) was evaluated to estimate actual evapotranspiration (ETa) above a drip-irrigated Merlot vineyard, located in the Talca Valley, Region del Maule, Chile (35° 25' LS; 71° 32' LW ; 136m above the sea level). An automatic weather system was installed in the center of the vineyard to measure climatic variables (air temperature, relative humidity, and wind speed) and energy balance components (solar radiation, net radiation, latent heat flux, sensible heat flux, and soil heat flux) during November and December 2006. Values of ETa estimated by the SW model were tested with latent heat flux measurements obtained from an eddy-covariance system on a 30 minute time interval. Results indicated that SW model was able to predict ETa with a root mean square error (RMSE) of 0.44 mm d-1 and mean absolute error (MAE) of 0.36 mm d-1. Furthermore, SW model predicted latent heat flux with RMSE and MAE of 32 W m-2 and 19W m-1, respectively