Increasing Water Demand Research Articles

Intersectoral Competition for Water Between Users and Uses in Tamil Nadu-India

Water is a manageable asset for drinking, food creation, and industry, and demand increases as the population increases. Water for irrigated agriculture, industry and domestic needs in India will go up to 1,072, 130, and 102 billion m3 (BCM) by the year 2050. In the state of Tamil Nadu in 2025, water needs for irrigation, domestic, livestock, and industrial sectors will be 52.7, 1.5, 1, and 2 billion m3, respectively, against the available supply of 24.6 BCM of surface water and 23 BCM of groundwater during the same period. A balance between need and supply is often difficult to achieve. By the year 2050, some 60 per cent of the world’s population will live in cities. In India and Tamil Nadu, 38 and 48 per cent of people will live in cities. Tamil Nadu is the second most urbanized state in India with 48 per cent of its population living in cities. This urban push will demand a large share of common water resources and most of the reservoir systems will face increased water demand for non-agricultural purposes, bringing in imbalances with other sectors, namely agriculture. Contrary to mounting demand, it will be difficult to facilitate the growing need for water. Furthermore, there are social and environmental costs in terms of the diversion of water from agriculture to urban uses. The discharge of sewage and industrial effluents also pollutes surface and groundwater, affecting not only human health but also the entire ecosystem. This paper examines the water management challenges in Tamil Nadu, India with respect to meeting future water demands across competing sectors.

Reallocation of water resources according to social, economic, and environmental parameters

Population growth, urbanization, and industrial development have significantly increased water demands in many countries, raising the concerns about water resources sustainability to meet the needs of humans and the environment. Furthermore, the economy-oriented allocation of water resources has caused many socio-environmental problems. The main goal of this study is to develop a system dynamics modeling framework that integrates economic, social, and environmental dimensions for the decision of water resources allocation. The Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) is used to rank modeling scenarios and identify the best strategy for water allocation. In the application to East Azerbaijan province of Iran, six industry groups (including chemical, food and beverage, non-metal, machinery and equipment, metal, and textile), thirteen water allocation scenarios, and five criteria (including profit index, employment index, return of surface water, groundwater sustainability index, and total allocated water) were considered. The TOPSIS results showed that in the best scenario most water was allocated to the non-metal industry with a relative distance of 0.63 to the ideal solution. On the other hand, the current water allocation scenario ranked seventh, indicating that significant improvements are required to take into account the social, economic, and environmental factors for optimal reallocation of water resources among different industry users.

Late twentieth century rapid increase in high Asian seasonal snow and glacier-derived streamflow tracked by tree rings of the upper Indus River basin

Given the reported increasing trends in high Asian streamflow and rapidly increasing water demand in the Indian subcontinent, it is necessary to understand the long‐term changes and mechanisms of snow- and glacier-melt-driven streamflow in this area. Thus, we have developed a June–July streamflow reconstruction for the upper Indus River watershed located in northern Pakistan. This reconstruction used a temperature-sensitive tree-ring width chronology of Pinus wallichiana, and explained 40.9% of the actual June–July streamflow variance during the common period 1970–2008. The high level of streamflow (1990–2017) exceeds that of any other time and is concurrent with the impact of recent climate warming that has resulted in accelerated glacier retreats across high Asia. The streamflow reconstruction indicated a pronounced reduction in streamflow in the upper Indus River basin during solar minima (Maunder, Dalton, and Damon). Shorter periods (years) of low streamflow in the reconstruction corresponded to major volcanic eruptions. Extreme low and high streamflows were also linked with sea surface temperature. The streamflow reconstruction also provides a long-term context for recent high Asian streamflow variability resulting from seasonal snow and glaciers that is critically needed for water resources management and assessment.

Effects of cover crops and irrigation on ‘Tempranillo’ grapevine and berry physiology: an experiment under the Mediterranean conditions of Southern Portugal

In addition to irrigation, other viticultural practices such as soil management can be applied to improve grapevine (Vitis vinifera L.) quality responses and attenuate unfavourable environmental conditions. Cover crops in the interrow of irrigated vineyards change the dynamics of water extraction and it is expected that the patterns of vines’ water relations will be modified, also changing their productive responses. This study took place over two seasons in ‘Tempranillo’ grapevines in a vineyard in South Portugal, where a cover crop was sown in the inter-rows of half the study area (SCC) while maintaining resident vegetation in the remaining (RV). Five water regime treatments were applied: full irrigation (200 mm irrigation amount–I200); moderate irrigation (150 mm–I150); deficit irrigation (100 mm–I100); ultra-deficit irrigation (50 mm–I50); rainfed (I0). Measurements of predawn leaf water potential (ΨPD), stomatal conductance (gs), photosynthetic rate (An), and transpiration rate (E) were made during the final stages of the growth cycle. Data of soil water availability, yield and growth variables, and berries and wine composition were also used. Significant interactions between the effect of soil management and water regime were observed on ΨPD. A water competition effect exerted by the cover crop could be responsible for reduced water loss and carbon assimilation, whenever Spring rain is lower and/or the cover crop biomass development is not controlled. Differences in gs and An observed at midday and late measurements reflect the influence of the daily increase of atmospheric water demand. Stomatal closure of grapevines was less affected in plots of higher soil water storage capacity. The correlation between ΨPD and gs was higher in the midday and late measurements, pointing to the regulation of stomatal response in response to water availability and daily environmental conditions. Principal components analysis (PCA) evidenced an influence of water deficit on metabolic responses that benefit fruit and wine quality. The cluster analysis (CA) revealed that no significant cluster of cases was clearly controlled by soil management or water regime in the first season but, in the second, drier season, significant clustering more irrigation- than soil management-controlled showed that a predominant influence of irrigation should be expected for ‘Tempranillo’ grapevines grown under dry Mediterranean conditions.

Water-Centric Nexus Approach for the Agriculture and Forest Sectors in Response to Climate Change in the Korean Peninsula

Climate change has inherent multidisciplinary characteristics, and predicting the future of a single field of work has a limit. Therefore, this study proposes a water-centric nexus approach for the agriculture and forest sectors for improving the response to climate change in the Korean Peninsula. Two spatial models, i.e., Environmental Policy Integrated Climate and Integrated Valuation of Ecosystem Services and Tradeoffs, were used to assess the extent of changes in agricultural water demand, forest water supply, and their balance at the watershed level in the current and future climatic conditions. Climate changed has increased the agricultural water demand and forest water supply significantly in all future scenarios and periods. Comparing the results with RCP8.5 2070s and the baseline, the agricultural water demand and forest water supply increased by 35% and 28%, respectively. Water balance assessment at the main watershed level in the Korean Peninsula revealed that although most scenarios of the future water supply increases offset the demand growth, a risk to water balance exists in case of a low forest ratio or smaller watershed. For instance, the western plains, which are the granary regions of South and North Korea, indicate a higher risk than other areas. These results show that the land-use balance can be an essential factor in a water-centric adaptation to climate change. Ultimately, the water-centric nexus approach can make synergies by overcoming increasing water demands attributable to climate change.

Increasing Water System Robustness in the Netherlands: Potential of Cross-Sectoral Water Reuse

Water reuse has the potential to substantially reduce the demand on groundwater and surface water. This study presents a method to evaluate the potential of water reuse schemes in a regional context and demonstrates how water reuse propagates through the water system and potentially reduces pressure on groundwater resources. The use of Sankey diagram visualisation provides a valuable tool to explore and evaluate regional application of water reuse, its potential to reduce groundwater and surface water demand, and the possible synergies and trade-offs between sectors. The approach is demonstrated for the Dutch anthropogenic water system in the current situation and for a future scenario with increased water demand and reduced water availability due to climate change. Four types of water reuse are evaluated by theoretically upscaling local or regional water reuse schemes based on local reuse examples currently in operation in the Netherlands or Flanders: municipal and industrial wastewater effluent reuse for irrigation, effluent reuse for industrial applications, and reuse for groundwater replenishment. In all cases, water reuse has the potential to significantly reduce groundwater extraction volume, and thus to alleviate the pressure on the groundwater system. The water-quantity based analysis is placed in the context of water quality demands, health and safety aspects, technological requirements, regulations, public perception, and its net impact on the environment. This integrative context is essential for a successful implementation of water reuse in practice.

Treated municipal wastewater as a water source for sustainable aquaculture: A review

AbstractAquaculture has been the fastest‐growing food production sector during the last decades. The supply–demand gap for fish is constantly widening, and declining freshwater availability is becoming a major limiting factor for production. Exploring alternative water resources, such as treated wastewater (TWW), has become a growing strategy for coping with the increasing water demand in agriculture. Reuse of wastewater or TWW for agriculture and aquaculture has been practiced around the world for centuries. However, the extent of the practice and the scientific attention paid to TWW reuse for aquaculture are negligible compared to those for agricultural irrigation. The objectives of this review are to present the existing literature on treated‐wastewater‐fed aquaculture, to evaluate the prospective reuse of TWW for aquaculture and its economic appraisal, and to identify the scientific and legislative gaps and challenges towards implementation. Most of the published studies on fish culture in TWW suggest that it is feasible in terms of fish survival and growth. Research also shows that fish are safe for human consumption in terms of microbiological contamination and the bioaccumulation of heavy metals and certain organic‐micropollutants, with levels found to be in accordance with international standards for human consumption. Moreover, reuse of TWW as an alternative water source for aquaculture holds economic and environmental advantages. It appears that the sociocultural perception is a major barrier, which can be overcome by a combination of further research, legislation and public relations, which can support the implementation of TWW reuse for aquaculture.

Quantifying Streambed Dispersion in an Alluvial Fan Facing the Northern Italian Apennines: Implications for Groundwater Management of Vulnerable Aquifers

Groundwater management of alluvial aquifers facing the northern Italian Apennines is an important issue that is becoming more complicated due to ongoing climate changes and increased water demands. The large groundwater withdrawals, coupled with an overall worsening of the water quality, require detailed knowledge of the recharge mechanisms of these aquifers that can be useful for further adaptation measures. We have focused our attention on a selected alluvial fan in which 49 slug injections of hyperconcentrated solutions of NaCl allowed river discharges to be estimated in seven different hydraulic sections. Consequently, losses from the streambed were assessed for the six river reaches along with the corresponding uncertainties in the estimates. The study confirms the suitability of such tests for identifying sectors in which streambed losses are promoted and for quantifying the total recharge conveyed to underlying aquifers. In addition, it has been demonstrated that the total streambed losses can be further linked to river discharges in any gauge upstream of the alluvial fan thanks to linear regression. Once obtained, the latter makes monitoring groundwater recharge by stream losses in real time possible if a permanent measurement device (such as the common telemetry used for river discharge monitoring) is available.

An integrated modeling approach for mineral and metal transport in acidic rivers at high mountainous porphyry Cu systems

The natural occurrence of acid waters in mountainous porphyry Cu systems poses challenges for water management considering the increasing water demand and global environmental change. Unraveling the transport and fate of minerals and metals in these types of acidic river systems is crucial for environmental management. To this purpose, we develop a transport and a hydrogeochemical model by coupling five components: (i) hydrology; (ii) hydrodynamics; (iii) sediment transport; (iv) solute transport; and (v) hydrogeochemistry. Our study domain is the Yerba Loca creek, a high-altitude acid rock drainage (ARD) basin located in the central Andes, Chile. Water in the upper basin shows a low pH (around 3) and high aluminum, copper, iron, manganese, and sulfate concentrations. Our model reproduced the observed mineralogical and chemical processes by inducing the expected pH dependence on mineral precipitation along the river. Results showed good agreement between modeled and field data, highlighting the main processes that control the transport and fate of minerals and metals in mountainous river systems.

Hybrid Strategy for optimal scheduling of an integrated electrical water distribution system in presence of water and power producer under uncertain electricity price based on Stochastic/Robust Approach

Recently, seawater desalination is known as a way to face water distribution network challenges related to increasing water demand. A seawater desalination process generally requires a significant amount of heat generated by an electrical energy source. Therefore, the combined water and power (CWP) generating units are applied to reduce the electrical consumption of seawater desalination processes. In the CWP units, the heat energy required for seawater desalination is supplied by using the waste heat of the flue gases exhausted from the power generation part. Therefore, it is highlighted that the freshwater of the CWP unit is dependent on the amount of electrical power generated by this unit. The CWP power generation is usually related to the electrical price in separated electrical and water distribution networks. However, this value can be scheduled based on the value of water demand and electrical price in an integrated electrical-water distribution network. In this paper, a hybrid scheduling model based on stochastic/robust is proposed to minimize the operation cost of an integrated water-electrical system by considering the uncertainty of electricity price and technical constraints of electrical and water distribution systems. The proposed hybrid scheduling model is solved based on the price information obtained by executing an interval forecasting model. In other words, the upper and lower bound of price is forecasted in an interval forecasting model. Then, such parameters are used to find the worst of integrated electrical-water distribution systems against the electrical price uncertainty.

District Drinking Water Planning for Sustainability in Maharashtra: Between Local and Global Scales

Sustainable rural drinking water is a widespread aim in India, and globally, from the household to district, state, and national scales. Sustainability issues in the rural drinking water sector range from increasing water demand to declining groundwater levels, premature deterioration of village schemes and services, inadequate revenues for operations and maintenance, weak capacity of water operators, frequently changing state and national policies, and destabilizing effects of climate change. This paper focuses on the special role of district-scale drinking water planning, which operates at the intersection between bottom-up water demand and top-down water programs. After surveying the challenges associated with bottom-up and top-down planning approaches, we present recent efforts to strengthen district and block drinking water planning in the state of Maharashtra. A combination of district interviews, institutional history, village surveys, GIS visualization, and planning workshops were used to advance district planning goals and methods. Results assess bottom-up processes of water demand; top-down water programs and finance; and intermediate-level planning at the district and block scales. Discussion focuses on potential improvements in district planning methods in Maharashtra.

Long-term analysis of River Tisza water level data with regard to the ecological water demand of floodplain water bodies

One of the main threats of our time is the increasing water demand not only globally, but also locally. These are often met at the expense of ecological water demand, jeopardizing the structural and operational conditions necessary to maintain good ecological status in aquatic and wetland habitats. This is why it is of great importance to explore possible water retention options. In 2019, based on the long-term data series on the water level of River Tisza, we studied the frequency and extent of flooding in the floodplain between Tiszabercel and Gávavencsellő, where there are valuable wetlands, including a ‘sanctuary’-type backwater. This was necessary because recently the floodplains have undergone negative changes. Their water volume has gradually decreased, their valuable wildlife has become rarer, some of them have completely dried out in the autumn and even one of them has burned out. From the analysis of the examined 48-years data, it could be concluded that flooding was relatively frequent in the sampled area, but the extent of water coverage had no significant effect either in space or time. It was also found that only water levels above 700 cm (based on the water meter of Tiszabercel, 98.36 mBf) could adequately ensure that the water bodies are filled up and flushed out. However, there is little chance of this, because of four reasons: (1) water levels of this height are becoming rare; (2) the duration and height of high water levels are mostly short in time; (3) water levels of several water bodies are artificially decreased; (4) the drainage effect of the River Tisza – which has been significantly incised after the river regulation – prevails in the area. Due to all, in the future, there would be a great need to maintain the water levels in the floodplain wetlands as efficiently as possible after the floods – for which we have made specific proposals for the places and methods to preserve the ecologically necessary amount of water.

Estimating Future Peak Water Demand with a Regression Model Considering Climate Indices

Although Austria is a water-rich country, impacts of climate change on water supply are already noticeable. Some regions were affected by water scarcity in recent years. Due to climate change, an increase in peak water demand is expected in the future. Therefore, water demand prediction models that include climate indices are of interest. In this paper, we present a general multiple linear regression (GMLR) model that can be applied to selected study sites. We compared the performance of the GMLR model with different modeling approaches, i.e., stepwise multiple linear regression, support vector regression, random forest regression and a neural network approach. All models were trained with water demand and weather data reaching back several years and tested with the last available observation year. The applied modeling approaches achieved a similar performance. As a second step, the GMLR model was used to estimate the peak water demands for the time period 2025–2050. For the future water demand estimate, 16 different climate projections were used. These climate projections represent the worst-case climate change scenario (RCP 8.5). The expected increase in peak water demand could be confirmed with the modeling approach. An increase in peak water demand by 3.5% compared to the reference period was estimated.

Estimation of seasonal base flow contribution to a tropical river using stable isotope analysis

Increase in water demand within the Cauvery River Basin is a cause of serious concern over sustainable utilization and managment of water resources. Sustainable, efficent and equitable managment of Cauvery riverwater requires a thorough understanding of the contributing sources and hydrological processes influencing avaliability of water resources. The study investigates the seasonal contribution of surface runoff and baseflow to the Cauvery streamflow using isotope mass balance approach. Stable Isotope measurements (δ2H, δ18O) of Cauvery river water along with groundwater are carried during seasonal time intervals spanning from 2014 − 2016, covering pre-monsoon (PM), south-west monsoon (SWM) and north-east monsoon (NEM) seasons. Field campaigns yielded seasonal datasets of Cauvery riverwater and groundwater isotopic composition. Stable isotope analysis showed a seasonal shift in the river water isotopic composition (δ2H 8‰, δ18O 0.95‰) between pre- monsoon (PM) and south-west monsoon (SWM) seasons. Isotopically heavier values are recorded during the pre-monsoon season; coinciding with the period of low flow condition, whereas the monsoon season is characterized by high discharge and recorded isotopically lighter values. The Krishna Raja Sagar (KRS) Reservoir controls the isotopic composition of riverwater by evaporative process, during the pre-monsoon season resulting in river water becoming isotopically lighter. We utilized two-component mixing model to estimate the seasonal base flow contribution to the Cauvery River, for which the river is segmented into three sectors. The average base flow contribution to river flow during pre-monsoon season in sector I is 85 ± 5%, whereas in sector II and III the average groundwater contribution drops to 59 ± 3% and 39 ± 3% respectively. Similarly, the average base flow contribution to the river flow during south-west monsoon season drops to 32 ± 7% in sector I, whereas in sector II and III the average base flow contribution is estimated at 42 ± 7% and 47 ± 7% respectively. The base flow contribution is appreciably high in the upper Cauvery Basin comprising the Western Ghats, which plays a crucial role in sustaining stream flow during the pre-monsoon season. Assessment of spatial and temporal variability of surface water and groundwater isotopic composition within the Cauvery River Basin provides an important dataset for developing a sustainable river management plan in this tropical mesoscale riverine system.

Cross-sphere modelling to evaluate impacts of climate and land management changes on groundwater resources

Climate change affects both water resources and agricultural production. With rising temperatures and decreasing summer precipitation, it is expected that agricultural production will be increasingly limited by drought. Where surface- or groundwater resources are available for irrigation, an increase in water withdrawals for irrigation is to be expected. Therefore, quantitative approaches are required to anticipate and manage the expected conflicts related to increased water abstraction for irrigation. This project aims to investigate how agricultural production, water demand for irrigation, runoff and groundwater dynamics are affected by future climate change and how climate change impacts combined with changes in agricultural water use affect groundwater dynamics. To answer these research questions, a comprehensive, loosely coupled model approach was developed, combining models from three disciplines: an agricultural plant growth model, a hydrological model and a hydrogeological model. The model coupling was implemented and tested for an agricultural area located in Switzerland in which groundwater plays a significant role in providing irrigation water. Our suggested modelling approach can be easily adapted to other areas.The model results show that yield changes are driven by drought limitations and rising temperatures. However, an increase in yield may be realized with an increase in irrigation. Simulation results show that the water requirement for irrigation without climate protection (RCP8.5) could increase by 40% by the end of the century with an unchanged growing season and by up to 80% with varietal adaptations. With climate change mitigation (RCP2.6) the increase in water demand for irrigation would be limited to 7%. The increase in irrigation (+12 mm) and the summer decrease in recharge rates (~20 mm/month) with decreasing summer precipitation causes a lowering of groundwater levels (40 mm) in the area in the late summer and autumn. This impact may be accentuated by an intensification of irrigation and reduced by extensification.

Groundwater modeling from Tien Thanh to Ke Ga area, Binh Thuan province

The coastal area, from Tien Thanh to Ke Ga including Thuan Quy and Tan Thanh communes, is among the regions having a high economic growth rate of Ham Thuan Nam district, Binh Thuan province. The economic growth rate thanked to the development of coastal tourist sites and cultivating areas of dragon fruit, resulted in the increased water demand. Due to the limitation of the water supply system and surface water, the region's main supply comes from the groundwater. The massive and uncontrolled exploitation could lead to the exhaustion and pollution of water reservoirs in the coastal Quaternary aquifer. To serve the management and use of groundwater resources, we calculated the used reserves of the entire area by modeling the layer containing water in the area using the Modflow module of GMS software 10.4 (Groundwater Modeling System). The input data were collected through the suction pump experiment, water samples, survey on exploitation, and results of research reports of nearby areas. The normalized steady-state models showed that aquifers in the area were recharged by rainwater, and re-fed to rivers, partly forming the flows to the sea. If the amount of wasted water into the sea was considered as the total exploitable reserve, the used reserve of underground water in this area is 70,158 m3/day.

Optimal Model of Desalination Planning Under Uncertainties in a Water Supply System

A requirement for developing desalination efforts in coastal regions suffering water scarcity is proposed to address the increased water demand and limited traditional water supply. The determination of a plant capacity and water allocation scheme in a multiple-source water supply system, as the first problem in planning desalination under streamflow and water demand uncertainties, remains a challenge. To address this gap, an interval-parameter two-stage stochastic programming model is developed in this study. The first-stage problem is to determine a proper desalination plant capacity, and the second is the development of a water allocation scheme under the uncertainties of natural streamflows, water demands, benefits and economic losses. The objective function is to maximize the net benefit of the system, and the cost function of desalination, including capital and operational costs, implying environmental impact, is linearized within a range of plant capacities to solve the model. The proposed approach is applied to an urban area of Weihai in China to illustrate the validity of the model. The results suggest a capacity of 46 × 103 m3/d in 2030 and 55 × 103 m3/d in 2040. Sensitivity analyses of the parameters indicate that a decrease in the unit price of electricity leads to an increase in the utilization level of desalinated seawater. A complementary relationship was observed between reclaimed water and desalinated seawater, in that a decrease in the use rate of reclaimed water from 0.38 to 0.18 led to a 15% increase in desalinated plant capacity.

Enhanced strength and microstructure of dredged clay sediment-fly ash geopolymer by mechanochemical activation

A low reactivity dredged high plasticity clay rich in quartz and alumina was obtained from an intercoastal waterway in southeast Texas and mechanochemically treated with fly ash and sodium silicate and used to manufacture a geopolymer mortar. The treated dredged clay and fly ash precursor was activated with a liquid sodium hydroxide solution. Ten different mixes were considered to study the effects of mechanochemical treatment, mixing procedure, and fly ash replacement dosage. The compressive strength, the reactivity during thermal curing, degree of polymerization, and microstructure and morphology were investigated using isothermal calorimetry, Fourier-transform infrared spectroscopy, nano-indentation, and optical and scanning electron microscopy. Co-grinding fly ash, sodium silicate, and dredge clay enhances the bulk reactivity and dispersion of the blended precursor which enhances the connectivity of the geopolymer, intensifies the polymerized structure, increases compressive strength, and lowers the matrix pore size surface area despite increased water demand and some physical interferences from the dredge clay sediment. The efficacy of the mechanochemical treatment will largely depend on the quantity and reactivity of the fly ash present in the geopolymer. The inert dredge high plasticity clay sediment serves as an effective filling agent in geopolymer systems up to 50% replacement. However, the mechanochemical treatment of a blended fly ash-dredge clay system is most effective in increasing compressive strength (by ~ 30 MPa) when the inert dredge clay sediment is less than or equal to 25% of the total precursor mass.

A REVIEW OF STUDY ON REMOVAL OF SOME BIOLOGICAL AND CHEMICALPOLLUTANTS FROM WATER/WASTEWATER USING DIFFERENT TYPES OF NANOMATERIALS IN TURKMENISTAN

The results reached by the research confirm and point outthat the expansion of industry's economic capacity and the transition to market mechanisms for the development of the economy cause a reductionin reserves of clean water, shallowing of mountain and trans-boundary rivers, the decline of fish stocks, and the emergence of a real threat of a water ecological crisis in the republic.The increasing water demand with stringent health standard and emerging contaminants caused that the traditional water/wastewater treatment technologies remain ineffective for providing adequate safe water.Now, nanotechnology-based multi-functional and highly efficient processes are providing affordable solutions to water/wastewater treatments that do not rely on large infrastructures or centralized systems. The present study is briefly discussed the availability and practice of different nano-materials (particles or fibers) for removal of bacteria, inorganic solutes, heavy metals, metal ions, complex organic compounds, natural organic matter, nitrate, and other pollutants found in surface water, ground water, and/or industrial water.Recently, nano-technology and nano-scienceare greatly developedand produced environmentally-safe, economical, and efficient materials for environmental engineering, these engineered nano-materials are promising for water treatment due to their unique physicochemical properties that enable the heavy metals scavenging with high adsorption capacity and selectivity even at very low concentrations.Efficient heavy metals removal from water was reached via the simple adsorption technique. The current review discussed the heavy metals were removed by using various Nano-materials like zeolite, polymers, chitosan, metal oxides, and metals under different conditions. The new studies focused on nano-materials functionalization in order to improve properties of separation, stability, and adsorption capacity. Different molecules such as bio-molecules, polymers, inorganic materials were used in functionalization process. By providing the magnetic properties to the adsorbent, its separation becomes easier via magnetic separation techniques. This review provided precious information regarding the use of engineered nano-materials for the removal of toxic heavy metals that will guide the researchers intending to fabricate new nano-materials for water/wastewater remediation. It should be noted, that all experiments are conducted at lab-scale for toxic metals in aqueous solutions and studies are needed to evaluate the process efficiency at pilot and large scale using real wastewater

Population Assessment and Conservation Strategies of the Indus River Dolphin, Platanista gangetica Minor, in Indus River Sindh, Pakistan

Indus Blind Dolphin is endangered species sighted in the Indus River from the Indus delta upstream to the Himalayan foothills prior to building barrages but the maximum number of this mammal is found in Guddu to Sukkur reach and lowest number at upstream of Guddu barrage and downstream of Sukkur barrage. Driving forces for water and dolphin reserve conservation are an agriculture-environmental trade-off, water use and alteration of rivers for irrigation and agriculture and inadequate consideration on the habitat of highly valuable species such as Platanista gangetica minor, water demand increase with urban development and industrial activities, water pollution from Industries and agriculture wastewater, fishery-dolphin conflict causes physical damage to dolphins by boat and unintended dolphins/fish catch by gillnet.This paper presents the assessment of threats to Indus dolphin population growth, water quality, and other risk activities in stretch Guddu to Sukkur barrages. The total 1419 Indus dolphin was counted during a survey of dolphin in 2019, while918 in2011 respectively between Guddu and Sukkur Barrages. As result, 501 Indus dolphin number has increased in a period of 8 years. The analyzed results reveal that all the tested parameters ie. pH; Cond, TDS; Cl, TH, Alk, SO4, and NO2 are within the permissible limits as per standards NEQS and WHO. Moreover, the Standard Deviation of all parameters shows low deviation at different locations. The correlation matrix of all parameters of collected samples. The pH has a very strong correlation with NO2, and SO4 has a strong relation with conductivity and total hardness, and alkalinity.