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The water deficit in Nzhelele-Makhado area calls for an efficient assessment to delineate and map existing alternative water resources for future extraction. We are of a view that the identification of groundwater potential zones (GWPZ) in an area is as equally important as determining the most effective groundwater mapping models for the efficient production of reliable GWPZ maps. Consequently, relative frequency ratio (RF), with predictor value, and analytic hierarchy process (AHP) models, including two RF-AHP hybrid models (HM-A and HM-B) were applied and compared to evaluate their effectiveness and accuracy in groundwater potential mapping of Nzhelele-Makhado area. HM-A model is based on the ranks of classes of groundwater controlling factors that were computed by RF model and weights of controlling factors computed by AHP model. Meanwhile, for HM-B model it was vice versa. Eight groundwater controlling factors (slope, geomorphology, lithology, lineament density, soil, rainfall and land use land cover) were considered for this assessment. These were derived and extracted from conventional and remotely sensed datasets. The resultant GWPZ maps computed by the four models were classified into five categories: very low, low, moderate, high and very high groundwater potential zone. The RF, AHP, HM-A and HM-B has an area coverage of 13.62%, 21.50%, 14.56% and 19.62%, respectively, in very high potential zone. The area under curve (AUC) was used to assess the accuracy of the four models and evaluate the resultant maps using 37 geosites in the area. The RF, AHP, HM-A and HM-B show the AUC value of 72.47%, 60.55%, 71.96% and 49.85%, respectively. The models based on RF-derived ranks show better accuracies than models based on AHP-derived ranks. This suggest that the ranks have more influence in the performance of models than weights. The weights derived by AHP and RF models were generally consistent; thus, confirming that the ranks have more influence on the resultant maps. The maps generated from RF-derived ranks can therefore be used for further ground-based investigation of groundwater potential sources in the area.

This study was conducted at Sungai Burong Tanjung Karang Kuala Selangor, Malaysia to investigate the effects of planting methods and techniques on planting quality. The problem is that the farmers do not follow Rice Check quality points in land preparations for flooding, drainage, and water depth which affects the planting quality (planting density, spacing, and planting losses). The results showed that following standardized practices has a positive effect on planting quality. Soil penetration resistance and soil bulk density decrease with the increase of the field flooding period and increase with the sedimentation period increase. Soil penetration resistance and bulk density have a negative effect on planting losses. The working speed of the transplanting machine was affected by the field condition SPR, Db, and WC affect the transplanting speed which affects the planting quality (planting density, spacing, and planting losses). The flooding period has a positive effect on planting losses, while the sedimentation period has a negative effect. Floating hills and buried hills decrease with the increase of flooding periods, and water depth, and with the decrease of the sedimentation soil penetration resistance, and soil bulk density. Bulk density and soil penetration resistance have a positive effect on planting density and spacing as they decrease, planting density and spacing decreases, and vice versa. The flooding period has a negative effect on planting density and spacing, while the sedimentation period has a positive effect. About 50.5% of the farmers used the right required amount of water for irrigation, and also the right time for irrigation.

Groundwater potential and aquifer vulnerability in some part of Akure metropolis southwestern Nigeria was carried out, using electrical resistivity survey, to identify and determine possible areas for groundwater development and its aquifer vulnerability. Geoelectric parameters from electrical resistivity survey helped in characterizing, assessing and evaluating the hydrogeological condition of aquifers in the area. A way of integrating all aquifer parameters significant to evaluating the groundwater potential and vulnerability, using the principle of Drastic and Multi-Criteria Evaluation Techniques, was proposed. The investigated area was classified into low, moderate and high groundwater prospect and aquifer vulnerability using the proposed method. The approach allows the weighting and integrating of all aquifer parameters in order of their significance to aquifer vulnerability. Integration of geophysical method with the proposed data management method provided a cost effective, dependable and accurate characterization and evaluation of an aquifer system.

Hydrologists must have huge theoretical and practical knowledge of irrigation networks such as rivers, canals, streams, channels, and minors. Because whole irrigation system relies on a gauge and discharges relationship which is essential for controlling floods, water resource management, and hydrologic modeling. The true and consistent figures of flow rate in the irrigation system are important for irrigation water efficiency. Mostly, Hydrologic modeling activities like hydraulic structures, designs, and management of surplus water in canals are subjected to the flow of irrigation water which is derived from the rating curve (RC). The managing of irrigation water in the system must be essential for crop water requirements and estimation of seepage losses. Thus, to fulfill the objectives, field activities (discharge measurement) were conducted in Golarchi minor of the Left-bank area water board. The main target was to calculate real discharge at different gauge levels and to develop a rating curve and rating table for the accurate distribution of irrigation water in the command area. Hence, the discharge was measured with a current meter and the area velocity method was employed for flowing water. The discharge was taken at three different gauges i.e., 1.2ft, 1.34ft, and 1.55ft with the discharge of 51.921cusecs, 55.021cusecs, and 58.197cusecs. Then collected data was exported to MS Excel for manipulation and for developing rating curves. The power equation was developed for Golarchi minor for confirming the different discharges on different gauge heights. The results of the study calculated as 1.1ft gauge to 1.7ft gave discharge 50.383cusecs to 61.009cusecs. It is concluded that the present study suggested that there should have an automatic gauging station to know the real demand for irrigation water in the command area and di-siltation should be done.

Flood is one of the natural events in our environment. It destroys and displaces naturally existing structures found within the Hydrologic Response Units (HRUs). These include the Land Cover/Land use, Soil structure and the topography or the terrain. The method applied was the used of ArcSWAT to determine those flooded sub-basins by simply delineating the whole watershed into different sub-basin parameters. The result proves that what determines the flood influence was the area of the sub-basin that contained the HRUs not the HRUs itself. Once the sub-basin was inundated, the flooded streams within the sub-basins were calculated as flood impact. in this analysis 5 number of sub-basins were flooded in the watershed of Terengganu. Sub-basin number 3 has the highest flood impact with 14,699 hectares and sub-basin number 5 has the lowest total flood impact of 968.82 hectare.

Hazardous water contamination is a rising concern for the provision of usable and drinkable water to the world. Innovative, economic, and renewable technologies are the need of the hour for wastewater treatment. Several technologies have been reported to encourage wastewater treatment, such as ion exchange, co-precipitation, adsorption, membrane separation, oxidation, biochemical processes, etc. Among them, membrane separation technology has been considered a promising approach due to its short route and viable economics. Polymeric membrane-based technology comes with ease of functionalization, high sustainability, excellent adsorption, economic advantage, and environmental friendliness. That’s why, membrane processes were further developed to different separation mechanisms such as microfiltration (MF), ultrafiltration (UF), nanofiltration (NF), and reverse osmosis (RO). Herein, we report a mini review of polymeric membrane-based separation technology for wastewater treatment. The short communication includes the need for water purification and their purification by membrane technology, especially polymeric derived membranes. Besides, the state-of-art membrane and its utilization for the removal of various water contaminants were discussed. The proposed review would be helpful to provide a single platform to study about the role of polymeric membrane.

Under the situation of acute water crises and the regular or occasional use of marginal to saline groundwater by the farming community to cultivate the crops, the research needs to be conducted on the use of marginal to saline groundwater based on the guidelines and strategies for the effective use be developed. In context of this, the experiment was conducted at the field research station of the laboratory of the Department of Land and Water Management (LWM) Faculty of Agricultural Engineering (FAE), Sindh Agriculture University (SAU) Tandojam during the year 2019. The experiment was arranged in a completely randomized design with three treatments of varying water qualities with three replications were deployed. The treatments were: W1 = non-Saline water (canal water) E.C= 1.0 dS m-1, W2 = Saline water (groundwater) EC= 4 dS/m-1and W3= Saline water (groundwater) EC= 6 dS/m-1. Okra crop was grown on ridges. The results showed that the soil EC decreased 0.76 dS/m-1 under T1, and increased 0.83 and 1.33 dS/m-1 under T2 and T3, respectively. The soil pH decreased by 0.29, 0.43, and 0.44 under T1, T2, and T3. The soil Mg increased 21.57, 22.11, and 27.03; soil SAR increased 6.15, 7.82, and 8.91; and soil ESP increased 6.51, 8.61, and 10.33 under T1, T2, and T3, respectively. The soil Ca decreased 1.34 under T1 treatment; and increased 0.30 and 10.28 under T2 and T3, respectively. The maximum yield of 18500 kg ha-1 was found with T1 followed by 17391 kg ha-1 with T2 and the lowest yield of 16836 kg ha-1 was found with T3. The highest water productivity of 1.91 kg m-3 was found with T1 treatment followed by 1.79 kg m-3 with T2 treatment and the lowest water productivity of 1.73 kg m-3 was found with T3 treatment.

Human-induced anthropogenic variations cause a significant change in the local climate, which in turn lead to variations in different climatic regions. The effects of global warming have wide spatial variability, feedback of climate change, like, surface temperature towards precipitation, surface, and subsurface runoff are critical. As the climate, variability is critically important for nature and society, especially if it increases in amplitude and fluctuations become more persistent. However, the issues of weather surface temperature is changing, and if so, whether this has a positive or negative impact on precipitation, surface and ground runoff, and theirs distinguish response to different climate classes, are subjects of ongoing debate. The current research is mainly concerned with distinguishing the response of surface temperature on the precipitation, storm surface run off, and subsurface runoff on different climate classes over the mainland of Pakistan, for a time duration of 71 years, from 1948–2018. Here, we used monthly based two sets of GLDAS (Global Data Assimilation System) datasets i.e. GLDAS-2.0 (1948-2010) and GLDAS-2.1 (2011-2018) having the spatial resolution of 0.25°×0.25° for surface temperature, precipitation, and runoff. While, for regional based climatic classification, Köppen Grignard climate classification map was used. The spatial-temporal trend of all the involving parameters has been estimated using Mann-Kendall’s trend. Spatial-temporal variation in the precipitation, surface temperature, and runoff fluctuations have been detected in different climatic regions. We showed that annually based variability of surface temperature has positive feedback over the surface runoff over the entire region as well as different climate regions of Pakistan. Despite the declining precipitation trend, the temperature seems to be a major cause of the melting of glaciers leading to an increase in the runoff. Based on our findings of established trends and corresponding mechanistic ‘feedback’ we hypothesize that increasing temperature might risk severe water shortage and cause disastrous floods in the future. Furthermore, different climatic zoning’s surface temperature variability contributed to observed variation in the precipitation, surface, and subsurface runoff variability, which in turn contributed to the persistent droughts. Changes in surface temperature and their impact on precipitation and runoff deliver valued evidence for understanding the region’s sensitivity over the entire region in Pakistan.

Water distribution on earth is not constant in its both forms i.e. surface water and groundwater. In many areas, the groundwater availability is changing, making it less available to agriculture for irrigation purposes. Surface water has fresh quality and frequently used for irrigation practices by diverting water from rivers and stream into canals and watercourses. As this scare and valuable resource move into the irrigation structure, a certain part of that water is lost. The losses in the watercourses are much more than those in the main channels and distributaries. So farmer’s face critical shortage of irrigation water issues. In addition to this groundwater pumping is also increasing that is decreasing groundwater table. The conveyance losses in the watercourses can be minimized by applying some lining techniques. To overcome this problem, there is a need to work out of the channel lining that ensures maximum water saving. A detail study has been carried out in the work to calculate the water losses using operational inflow and outflow approach. The losses from the pre and post lining of the canal have been calculated and assess the impacts of hydraulic parameters of the channel after lining the channel to investigate the hydraulic outlet’s performance, seepage water losses from the channel. In this concern, a case study was conducted on channel lining of Faisalabad irrigation zone. The value of the hydraulic parameters (cross-sectional area, flow velocity, wetted perimeters, hydraulic radius, bed slope, and side slope) for the trapezoidal channel have been investigated in this study. For statistical analysis a generalized linear model (exponential) R-language were used in the study. The value of water losses in pre and post lining of three distributary Lagar Disty, Nasrana Disty and Sehti Wala Minor was 2.238, 1.805, 3.008 m3/s/106m2 and 0.385, 0.486, 0.644 m3/s/106m2 respectively. The lowest losses were found in lined channel of LCC (East) Lagar Disty and the highest losses were found in the LCC (West) of Sehti Wala Minor. In this investigation work, the saving of water through lining the channel is also authentic numerically evaluated and authenticated.

Watersheds are acknowledged as a paramount form of green substructure that provides us with important services like; drinking water, irrigation water, fodder/forage, pebbles/boulders, and timber including recreational, regulating, and other available services. The hills and mountains of Nepal are the watershed areas with the most fragile ecosystem and poor agricultural potential, as more than 15% of the total population of the country and 13% of the total land area is covered by Chure that has fragile ranges of hills. Hence, it can’t be denied from the fact that many of Nepal’s watersheds are in a state of physical and biological deterioration where landslides, soil erosion, floods, biodiversity loss, unsustainable water extraction, and farming practices are among the major issues leading towards watershed degradation. Therefore, proper strategies like developing stream and rainwater harvesting programs, strict implementation of EIA, IEE, adoption of SALT technology for income generation, etc. needs to be prioritized based on the principles of integrated watershed management while planning, monitoring & implementing soil and watershed management.