Increasing Water Demand Research Articles

Properties of Concrete with The Inclusion of Ceramic Waste As Coarse Aggregate

Ceramic tile waste, which is obtained from construction sites, demolition sites, and manufacturing industries, has a negative impact on the environment. Recycling these ceramic tiles to produce concrete could be a useful strategy for preserving the environment and enhancing the concrete's inherent qualities. To lessen the impact of waste materials on the environment, this study seeks to ascertain whether it is feasible to substitute waste materials from ceramic tiles as coarse aggregates in the production of concrete. Experimental studies were conducted and the concrete grade 30 was tested for slump test, compression test, and water absorption test, at various curing times of 7, 14, and 28 days. Additional water absorption of the CTA lead to increased water demand, which then increased the levels of porosity and reduced workability. The high porosity of the CTA concrete reduces the density of the concrete and has an impact on compressive strength. CTA has the probability to be used, but precaution needs to be required, especially for higher replacements that may influence the compressive strength and thus partial replacement is suggested.

Future Outlook of Fresh Water Supply and Demand in Selangor

Water is an essential resource for the well-being of humans as well as for ecosystems. In this regard, the increasing water scarcity areas has become one of the major problems faced by humanity. In Malaysia, Selangor is considered a water-stressed area due to the increase in water demand and limited suitable fresh water resources for treatment and distribution. The increase in population as well as urbanization and industrialization made the rivers in Selangor arguably the most polluted compared to other states. These situations result in a series of unscheduled water supply interruption over the years and negatively impact the majority of consumers. Projected water demand also indicates that the existing water supplies are not sufficient in the long run, therefore, it is deemed required to study the water demand and supply gap in Selangor to ensure the current water management is sustainable for the remote future. This paper mainly discusses on the current water production from Water Treatment Plants as well as projection of water demand which also foresee the future water deficit in Selangor. The method used in this study was based on review of secondary data acquired from available published report and website, while the assessment of water demand conducted comprise of calculation of projected population, projected domestic water demand, projected total water demand and water deficit up to year 2050. According to the result obtained, the existing water demand and supply in Selangor is 4,967 MLD, meanwhile, the projection of water demand in Selangor up to year 2050 is 7,011 MLD with the projected water deficit of 2,044 MLD. The findings of this paper are essential in water resources planning and management, particularly in terms of additional raw water supply that will be required to cater to the future water demand in Selangor.

A Risk-Based Framework to Evaluate Infrastructure Investment Options for a Water Supply System

Increasing water demand due to socio-economic development often requires structure-level interventions, e.g., infrastructure expansion of water supply systems to bridge the gap between demand and water supply. Evaluating different expansion options is critical to making informed decisions. This study focuses on evaluating infrastructure investment options from the reliability perspectives of a water supply system. The evaluation framework is comprised of probabilistic demand projections, stochastic streamflow generation, a mixed-integer programming, and system performance evaluation. Different “industry understood” performance metrics, e.g., annual reliability, maximum delivery capacity, the probability of unsuccessful status, and the magnitude of potential water shortage, can be employed to evaluate the performance of water supply systems. This framework has been applied to Tampa Bay Water, a regional supply agency on the west coast of Florida, United States. The probabilistic demand projections for the future (2021–2040) consider socio-economic projections and climate conditions based on the statistics of historical observations. The Latin Hypercube Sampling algorithm is used to capture the bivariate distribution of supply and demand. This mixed-integer programming is a daily system optimization that minimizes operational cost and considers operational constraints and preferences, e.g., water withdrawal permits, facility production capacity, and water production preferences. Current infrastructure capacity and operational conditions are defined as the baseline scenario. Two additional planning scenarios of expanding the treatment capacity of a surface water treatment plant by 75,708 m3/day [20 million gallons per day (mgd)] and 113,562 m3/day (30 mgd) in the year 2028 are investigated. Results reveal that annual reliability would increase with the expansion of surface water treatment plant capacity. The spatio-temporal supply and demand variability determines that the firm yield from the surface water treatment is less than its expanded production capacity. Except for low demand realizations in the future, the duration and magnitude of potential water shortage could be reduced in both scenarios with engineering intervention. Although this framework is demonstrated for a regional water utility in Florida, it can be applied to other water supply systems around the world.

Model Pemanfaatan Air di SMPN 28 Bandung sebagai Peraih Penghargaan Adiwiyata di Kota Bandung

Water is a very important component in supporting life. Water conditions in the country is currently experiencing a lot of problems . Along with the increasing growth in the number of human increasing water demand, while water availability decreases. Adiwiyata Award-Winning School is a school that is considered successful in creating the management and conservation of the environment in terms of one aspect of saving water resources in the school. The aims of research are (i) to determine the efforts made to conserve water consumption in school, (ii) to knowing the water management system and water balanc , and (iii) the factors that influence the success of water conservation programs in schools. The method used is a mix between qualitative and quantitative method . Qualitative methods are used to determine school policy to conserve water consumption , and water management systems in schools . Quantitative methods are used to determine the water balance and the factors that influence the success of water conservation programs in school. The results showed in an effort to conserve water consumption in schools developed policies based management and environmental conservation contained in the vision, mission , goals and objectives of the program , funding policies and programs in policy development RAKS for water-saving infrastructure. Water management system prepared through a phase of water conservation programs, planning activities and implementation of water conservation, the school has not made the of the evaluation phase of the program . Water balance at SMP 28 obtained the consumption of water used is still below with SNI standard The largest volume of water consumption is used for activities wudhu , urination and hand washing. Savings occur from the use of waste water from wash hands and wudhu, thereby reducing water consumption in school..

Assessing the Impact of Different Irrigation Levels on Starch Potato Production

In the view of increasing water demands in agriculture, efficient water use is a key factor in potato production. The aim of this study was to compare two deficit (80% and 90%) and one abundant (120%) gun sprinkler irrigation levels with the longtime used irrigation level of a farmer (100%). Irrigation was supplied during the 2021 growing season on a loamy sand site in Mecklenburg–Western Pomerania, Germany. Yield and tuber quality of the high-amylopectin potato (HAPP) variety “Waxy/Henriette” were assessed in a three-grade tuber size distribution. Five economic indicators were used to assess the suitability of the investigated irrigation levels to secure economic responses. Yield and starch yield did not significantly differ between the 90% (561.1 dt ha−1 and 102.0 dt ha−1) and the 100% irrigation levels (559.1 dt ha−1 and 102.3 dt ha−1), with total production increasing by 2.0 dt ha−1 and starch production decreasing by 0.4 dt ha−1 at the 90% irrigation level. Tuber lesions decreased the economic responses at all irrigation levels. Potentially, 87,469 m3 of irrigation water (125.8 m3 ha−1) could have been saved on the loamy sand starch potato sites of the local farm (695.3 ha) in 2021.

Adapting Irrigation Strategies to Mitigate Climate Change Impacts: A Value Engineering Approach

Water scarcity and climate change are posing new challenges to irrigation management. Climate change increases water demand and decreases crop yields. The aim of this paper is to propose a framework to select the most efficient irrigation strategy to mitigate the impacts of climate change and achieve food security. Value engineering (VE) methodology is utilized to assure the functionality of the strategy and add an element of creativity while creating the value alternatives. The life cycle cost (LCC) technique is utilized to provide the optimum irrigation strategy from an economic perspective. The findings showed three different value alternatives for different crops, soil types, and irrigation systems. This paper contributes to the current state of knowledge by a) utilizing the Value Engineering methodology in irrigation management studies; b) evaluating irrigation strategies to ensure efficient irrigation water management; and c) providing policymakers with a tool to incorporate the added value and functionality into their policies regarding irrigation water.

Hydro-geochemical Study of the Coastal Aquifer in Tripoli (Lebanon)

Groundwater geochemistry refers to the general chemical properties of water, particularly groundwater. Precipitation, volatilization, oxidation/reduction, sorption/partition, and complexation are processes involved in the distribution and fate of organic molecules in water. Determining hydrogeochemical facies is a great help for determining relationships and similarities among the chemistry of waters in an aquifer. This study focused on the coastal aquifer of Tripoli (Lebanon) with Mio-Quaternary age. It is considered as a confined aquifer and an important hydraulic reserve for domestic water use in the region. Recently, it underwent an urban development that leads to an increase in water demand causing a decrease in the piezometric level and a high-risk of deterioration to water quality through seawater intrusion and anthropic pollution. To understand the origin of mineralization and the mechanism of water hydro-chemistry variation and to provide a vision to underground water recharge, this study aims to analyze the hydrodynamic, piezometric, and geochemical characteristics of the coastal aquifer. The fluctuation of physicochemical parameters for cool and warm seasons has been studied and monitored for 16 coastal wells during April, May, and June 2020. Results were interpreted by using a statistical analysis called Principal Components Analysis (PCA). Cartographic of groundwater levels and concentrations for nitrate, chloride, sulphate ions, the ratio sulphate/chloride were determined by using SUFFER8 software. It can be noticed that the Mio-Quaternary formation at Tripoli consists of thick sedimentary sandstones and conglomerates with argillaceous roots, which provide significantly high permeability characteristics. It is mainly recharged from precipitations through karstic formations. Chemical analysis shows that bicarbonate ions (HCO3-), characterized by dissolution of carbonate rocks from geological upstream formations of Tripoli, means that the aquifer is subjected to intensive recharge of fresh water and snow melting making a hydrostatic equilibrium facing marine intrusion [1]. High contents of chloride and Sodium are due to anthropic contamination or seawater intrusion. However, Magnesium ion concentration assures this intrusion. Meanwhile, nitrates, sulfates and phosphorus high concentrations are related to wastewater leakage or agricultural activities [2].

Effects of Land Consolidation and Precipitation Changes on the Balance of Water Supply and Demand in Western Jilin

As an important ecosystem service, water supply is closely related to human well-being. Maintaining the balance of water supply and demand is essential in the sustainable development of a regional economy and society. Taking western Jilin, where the difference between water supply and demand is increasingly prominent, as the research object, from the perspective of land consolidation and precipitation changes, this paper analyzes the temporal and spatial changes of water resources supply and demand at the regional and county scales in western Jilin from 2000 to 2018 by the InVEST model and the water resource demand model. The results show that water production in western Jilin did not change significantly before and after land consolidation. The change in planting structure made water demand increase from 3.03 billion m3 to 4.96 billion m3, which reversed the relationship between supply and demand. The impact of precipitation changes on water production is extremely significant. The annual production of water in wet years is 8.05 billion m3, and the annual water production in dry years is 1.08 billion m3. The amount of precipitation can directly change the relationship between the supply and demand of local water resources. The evolution of the water resources supply and demand pattern in western Jilin is the result of the combined effect of land consolidation and precipitation changes. Precipitation mainly affects supply, while land consolidation mainly affects demand.

Ecological relevance of non-perennial rivers for the conservation of terrestrial and aquatic communities.

River conservation efforts traditionally focus on perennial watercourses (i.e., those that do not dry) and their associated aquatic biodiversity. However, most of the global river network is not perennial and thus supports both aquatic and terrestrial biodiversity. We assessed the conservation value of nonperennial rivers and streams (NPRS) in one of Europe's driest regions based on aquatic (macroinvertebrates, diatoms) and terrestrial (riparian plants, birds, and carabid beetles) community data. We mapped the distribution of taxa at 90 locations and across wide environmental gradients. Using the systematic planning tool Marxan, we identified priority conservation sites under 2 scenarios: aquatic taxa alone or aquatic and terrestrial taxa together. We explored how environmental factors (runoff, flow intermittence, elevation, salinity, anthropogenic impact) influenced Marxan's site selection frequency. The NPRS were selected more frequently (over 13% on average) than perennial rivers when both aquatic and terrestrial taxa were considered, suggesting that NPRS have a high conservation value at the catchment scale. We detected an underrepresentation of terrestrial taxa (8.4-10.6% terrestrial vs. 0.5-1.1% aquatic taxa were unrepresented in most Marxan solutions) when priority sites were identified based exclusively on aquatic biodiversity, which points to a low surrogacy value of aquatic taxa for terrestrial taxa. Runoff explained site selection when focusing on aquatic taxa (all best-fitting models included runoff, r2 =0.26-0.27), whereas elevation, salinity, and flow intermittence were more important when considering both groups. In both cases, site selection frequency declined as anthropogenic impact increased. Our results highlight the need to integrate terrestrial and aquatic communities when identifying priority areas for conservation in catchments with NPRS. This is key to overcoming drawbacks of traditional assessments based only on aquatic taxa and to ensure the conservation of NPRS, especially as NPRS become more prevalent worldwide due to climate change and increasing water demands.

Factors Influencing Seasonal Changes in Inundation of the Daliyaboyi Oasis, Lower Keriya River Valley, Central Tarim Basin, China

The ecological water diversion project (EWDP) in the Tarim River Basin, China, aims to allocate more surface water to downstream reaches to restore the degraded ecosystems. However, seasonal changes in ecological water diversion; the factors (natural and anthropogenic) controlling the ecological water diversion, whether the seasonal delivery of water temporally corresponded to the vegetation’s seasonal water demands; and the benefits of the ecological water diversion through overflowing surface water irrigation are unclear. To address the above issues, this study examines the intra-annual changes and its influencing factors in ecological water diversion (inundation) in the Daliyaboyi Oasis in the lower Keriya River valley within the Tarim Basin, discusses whether the seasonal delivery of water temporally corresponded to the vegetation’s seasonal water demands, and assesses the ecological benefits of overflowing surface water irrigation. Inundation was quantified by digitizing monthly changes in the inundated area from 2000 to 2018 in the oasis using 184 Landsat images. The results demonstrate that seasonal changes in the inundated area varied significantly, with maximum peaks occurring in February and August; a period of minimal inundation occurred in May. Differences in the July/August peak (i.e., July or August) in inundation dominated the inter-annual variations in the inundated area over the 19-year study period. The two peaks in the inundation area were temporally consistent with the vegetation’s seasonal water demand. Local residents have used ecological water to irrigate vegetation in different parts of the oasis during different seasons, an approach that expanded the inundated area. The February peak in the inundated area is closely linked to elevated downstream groundwater levels and the melting of ice along the river. The August peak is related to a peak in runoff from headwater areas. The minimum May value is correlated to a relatively low value in upstream runoff and an increase in agricultural water demand. Thus, natural factors control the intra-annual and inter-annual variations in the inundated area. Humans changed the spatial distribution of the inundated area and enhanced the water’s ecological benefits, but did not alter the correlation between peak periods of inundation and vegetation water demand. The results from this study improve our understanding of the benefits of the EWDP in the Tarim River Basin.

Single-Cell Level Measurements of Photocatalytic Damage to Escherichia coli Cells

The increase in water demand due to the increasing population and the addition of emerging contaminants like drug-resistant bacteria, pharmaceuticals, and treatment-resistant chemicals such as PFAS are straining the current water treatment infrastructure. This straining infrastructure could be complemented by photocatalysis and other Advanced oxidation processes (AOP) [1] [2]. Photocatalytic water treatment methods, specifically, have generated a lot of interest due to their ability in eliminating pollutants like dyes and other toxic organic pollutants as well as eliminating pathogens such as bacteria, fungi, and viruses while minimizing the use of material resources. The elimination of bacteria by photocatalysis has been reported widely, with many reports focusing on the kinetics of photocatalytic disinfection, as well as some aspects of process scale-up. However, the mechanism for photocatalytic damage to the bacterial cells has thus far proven difficult to study [3] [4].It is critical to determine the mechanisms of photocatalytic disinfection for the development of better methods of catalyst discovery and reactor design. The mechanisms can be determined if quantitative data on how single bacterial cells interact with catalysts is available. However, experimental measurements at a single-cell level are relatively few and assays for evaluating photocatalyst performance in real-time have not been developed to our knowledge. In this work, we addressed these shortcomings with a combination of light microscopy and particle-tracking algorithms. Using nanowire-shaped titanium dioxide (TiO2) catalyst particles, which maintain a high surface area while remaining visible using the established techniques for light microscopy, we investigated the interactions between catalyst particles and bacteria. We quantified cell motility during the course of photocatalytic disinfection as a loss in motility is expected to faithfully track damage to the membrane [5]. We further correlated the kinetics of antibacterial action of the photocatalytic treatment in E. coli with real-time changes in membrane integrity. Our investigations are anticipated to reveal the mechanisms by which photocatalytic treatments cause cell damage. Such single-cell approaches are expected to help build libraries of photocatalysts and optimize the use of antibacterial agents against superbugs, with a range of future applications in water-disinfection reactors to hospitals.REFERENCES[1] X. Qu, J. Brame, Q. Li, P.J. Alvarez, Nanotechnology for a safe and sustainable water supply: enabling integrated water treatment and reuse, Accounts of chemical research, 46 (2013) 834-843.[2] A. Boretti, L. Rosa, Reassessing the projections of the world water development report, NPJ Clean Water, 2 (2019) 1-6.[3] O.K. Dalrymple, E. Stefanakos, M.A. Trotz, D.Y. Goswami, A review of the mechanisms asnd modeling of photocatalytic disinfection, Applied Catalysis B: Environmental, 98 (2010) 27-38.[4] H.A. Foster, I.B. Ditta, S. Varghese, A. Steele, Photocatalytic disinfection using titanium dioxide: spectrum and mechanism of antimicrobial activity, Applied microbiology and biotechnology, 90 (2011) 1847-1868.[5] R. Gupta, K. Y. Rhee, S. D. Beagle, R. Chawla, N. Perdomo, S. W. Lockless and P. P. Lele, Indole modulates cooperative protein-protein interactions in the flagellar motor, PNAS Nexus (2022)

Attributes of the Water Supply Program in Soppeng regency, South Sulawesi

Decreasing water availability and increasing water demand have occurred in Soppeng regency, this is due to the potential of surface water as raw water for clean water is increasingly limited. In ensuring the sustainability of the clean water supply program in Soppeng regency, it is necessary to study the water supply using a system approach, so that the water supply in Soppeng regency can be sustainable. This research was conducted with the aim of analyzing the constraints faced, program needs, and institutions that play a role in the supply of clean water in Soppeng regency with the Interpretative Structural Modeling (ISM) method. The results show that for the implementation of the clean water supply program, there are four key elements that need attention: the lack of institutional capacity, weak institutional governance, availability of raw water, and the role of Central Government (relevant ministries).

DOMESTIC DEMAND ANALYSIS FOR THE AVAILABILITY OF CLEAN WATER AT MAULAFA DISTRICT

The rapid population growth of an area is usually followed by an increase in water demand. The current availability of water is not necessarily able to meet the increasing demand for clean water. Therefore, it is necessary to estimate how much clean water is needed for each household water tap in a community. Estimation is carried out by interpreting the current and projected number of residents and customers and comparing it with the production capacity of existing water sources. The results of the analysis based on the population growth rate and the number of customers show that the current demand for clean water is 135.80 liters/second, while the demand for clean water in the next 10 years is 165.26 liters/second, and 93.79 liters/second. The current ratio is 0%, while for the next 10 years the ratio will be 122% and 69%. Based on the population growth rate until 2030, the existing availability of clean water is not able to meet the future water demand of the community, while, based on customer growth, the availability of clean water is still able to meet the future water demand of customers.

On the role of the architecture for spring discharge prediction with deep learning approaches

AbstractUnderstanding karst spring flow is important to accommodate the increasing water demand caused by the population growth and manage the freshwater water resource effectively. However, due to the spatial and temporal heterogeneity and complex hydrological processes in karst systems, predicting karst spring discharge remains challenging. In this study, three deep learning‐based models, including long short‐term memory (LSTM), gated recurrent unit (GRU) and simple recurrent neural network (RNN), are framed with an encoder–decoder architecture to provide multiple‐step‐ahead spring discharge prediction. The encoder–decoder architecture includes an encoder that reads and encodes the input sequence into a vector and decoder that deciphers the vector and outputs the predicted sequence. Three hybrid models called LSTM‐ED, GRU‐ED and simple RNN‐ED are compared with single‐step models and multiple‐step models without the encoder–decoder architecture to investigate the role of the encoder–decoder architecture on multi‐step‐ahead prediction. The sensitivity of the selection of input time and lead time steps on the karst spring discharge prediction is evaluated. The predicted results are compared with the observed spring discharge. It implies that: (1) LSTM‐ED, GRU‐ED and RNN‐ED models obtain similar results on predicting karst spring discharge multiple time steps ahead; (2) three hybrid multiple‐step models outperform the single‐step models in making consistent and accurate spring discharge predictions; (3) the multiple‐step models framed with an encoder–decoder architecture obtain better spring discharge prediction results than the single‐step models and multiple‐step models without the encoder–decoder structure; (4) the LSTM‐ED, GRU‐ED and simple RNN‐ED models are sensitive to the selection of lead time and insensitive to the selection of input time step. A short lead time typically yields a more accurate spring discharge prediction.

The Efficiency Assessment of Poly-Aluminium Chloride (PAC) in Water Treatment Plant Process: A Case Study at Sultan Iskandar Water Treatment Plant, Johor

The rate of population growth and river pollution are significant factors contributing to the increase in water demand in Johor. Generally, this may affect the quality of water treated at one of the biggest water treatment plants in Johor namely Sultan Iskandar Water Treatment Plant (SIWTP). The coverage of SIWTP water supply is wide and comprise almost all area of Pasir Gudang and half of the Johor Bahru district. This situation indirectly affects consumer demand when the treated water is insufficiently supplied by the potable water supply provider due to the use of conventional coagulants in the water treatment plant process. Therefore, this is an initial study as the Poly-Aluminium Chloride (PAC) coagulant is still in the early stages of implementation at SIWTP. It is important to determine the performance of PAC coagulant in the coagulation-flocculation process of the water treatment plant. The PAC performance is compared to Aluminium Sulphate which is a common type of coagulant used in the treatment plant, in order to establish efficiency. A pH adjustment test, turbidity test and the residual Aluminium test were conducted for both coagulants and six jar test readings were recorded to plot the comparison graph between PAC and Alum coagulants. The results showed that PAC is more efficient with 83.74% as compared with Alum which has an efficiency rate of 83.35%. Even though the difference is too small, it is concluded that PAC has better performance and is more efficient compared to Alum due to its better coagulation performance. In addition, PAC produces lesser residual Aluminium and required a lesser amount of dosage. This may reduce cost and therefore save overall operating costs.

Evaluating knowledge, awareness and associated water usage towards hand hygiene practices influenced by the current COVID-19 pandemic in Bangladesh

Hand hygiene is considered as one of the most effective ways for preventing transmissible diseases, especially for preventing virus-borne diseases. The study has been conducted to evaluate changes in knowledge, awareness and practices of hand hygiene due to the outbreak of the coronavirus disease (COVID-19) in Bangladesh. The potential factors influencing human behaviours for maintaining hand hygiene have also been explored. Moreover, a probable increase in daily water demand associated with the changed situation has been assessed. An online survey was performed among a total of 367 Bangladeshi residents about their practices of hand hygiene during pre-corona, corona, and of their perceived future practices at post-corona period. It has been observed that a significant percentage (62.1%) of the respondents have received basic hygiene education at any level of their academic education. Nevertheless, their hygiene practices were very poor before the COVID-19 pandemic. The outbreak of the COVID-19 has reinforced their previous knowledge and greatly influenced their behavioural changes towards practicing hand hygiene as per World Health Organization guidelines for preventing the virus outbreak. The changes, however, have created increased water demand. The estimated water usage is found to be 2.68 times (9.15 L/c/d) and 2.52 times (8.59 L/c/d) higher in the corona and post-corona period respectively than that of the pre-corona situation (3.41 L/c/d). The principal component analysis (PCA) elucidated that an individual's practice of hand hygiene was associated with income, level of academic and hygiene education, and the COVID-19 outbreak itself. Moreover, the influence of hygiene education and COVID-19 outbreak affecting the duration of handwashing are found highly significant (p-value < 0.001) from the regression analysis. Raising awareness towards behavioural change of an individual about water usage, improvement of academic curriculum regarding hand hygiene and provision of water pricing are recommended to attain sustainable development goals of the country.

Optimization of extreme learning machine model with biological heuristic algorithms to estimate daily reference evapotranspiration in Hetao Irrigation District of China

ABSTRACT Due to frequent drought events, increased water demand for agricultural production and limited, accurate estimation of reference evapotranspiration (ETo) is necessary for developing crop irrigation schemes and rational allocation of regional water resources. The extreme learning machine (ELM) was optimized using four biological heuristic algorithms, namely, Grey Wolf Optimizer (GWO-ELM), Moth-Flame Optimization (MFO-ELM), Particle Swarm Optimization (PSO-ELM), Whale Optimization Algorithm (WOA-ELM), and besides three types of empirical models (temperature-, radiation-, and mass transfer-based), and Penman model (P-M) were also applied to estimate the daily ETo in the Hetao irrigation district (HID). The results demonstrated that GWO-ELM obtained the highest estimation accuracy (R2 = 0.945–0.955; RRMSE = 14.52–15.29%; MAE = 0.124–0.141 mm d−1, and NSE = 0.942–0.952) at all stations when using mass transfer combination (Tmax, Tmin, RH, u2) as models input, and the GWO-ELM hybrid model outperformed other models. Herein, the biogenic heuristic algorithm can effectively enhance the ELM performance in ETo estimation, it was strongly recommended for estimating daily ETo in the HID using the hybrid GWO-ELM model and mass transfer combination as input. The optimized hybrid algorithms, especially GWO-ELM, can accurately estimate daily ETo with limited meteorological data, which can provide scientific guidance for the development of precision agriculture in the HID. Abbreviations: ANN: artificial neural network; BP: back propagation neural network; CMA: China Meteorological Administration; D-T: Dalton; EL: elevation; ELM: extreme learning machine; ETo: reference evapotranspiration; GEP: gene expression programming; GP: genetic programming; GWO: gray wolf optimization; H-S: Hargreaves-Samani; MFO: moth flame optimization; ML: machine learning; P-M model: FAO-56 Penman-Monteith (P-M) model; P-T: Priestley-Taylor; PSO: particle swarm optimization; RF: random forest; R-O: Rohwer; SVM: support vector machine; SVR: support vector regression; WOA: whale optimization algorithm

Physiological basis to assess barley response to optimized regulated deficit irrigation for limited volumes of water (ORDIL)

Agriculture must improve the productivity of irrigation water due to several factors, such as global warming, the increasing water demand of other sectors or the protection of the environment. The “optimized regulated deficit irrigation for limited volumes of water” (ORDIL) methodology may contribute to reach this objective by optimizing the allocation of irrigation water during the growing cycle, when the available volume is lower than the crop irrigation requirements. ORDIL was applied to a barley crop in a 3-year (2015–2017) field test under the semiarid conditions of Albacete (Spain). The main aim was to assess the influence of ORDIL on the physiological response of barley. The specific objectives were: 1) Identify if stomatal conductance (gs), net assimilation rate (An), intrinsic water use efficiency (WUEi) and total dry matter (TDM) evolution can be used as early and sensitive indicators of barley water status and crop performance; 2) Provide a mechanistic basis to understand barley physiological response to deficit irrigation at the most sensitive stages and; 3) Evaluate barley physiological response to ORDIL and its relation with yield. Thus, five irrigation treatments were performed. One without deficit (ND), and four with limited volumes of irrigation water (100%, 90%, 80% and 70% of typical irrigation needs). According to the results, gs was a reliable variable to detect early water deficit in barley. Besides, critical thresholds for this variable were found to optimize irrigation and to avoid chronic physiological damages affecting the most sensitive and yield-related stages. In summary, the physiological approach applied in this study validates ORDIL methodology being useful for future irrigation scheduling and distribution improvements.

A systematic approach for assessing water, energy and food security during the COVID-19 pandemic: case study of Mexico.

Assessing the security of the water–energy–food nexus is a topic of great importance, which allows determining the situation of each resource to implement actions for sustainable management of these resources in today's society. For this reason, a systematic procedure is proposed to evaluate the synergies of the water–energy–food nexus in a large region that is divided into subregions that allow considering their interactions. The new procedure considers the availability, accessibility and regional interdependence of resources while annexing economic and social aspects. A composite index called the WEF Global Index is developed, which involves the WEF nexus index and has nine indicators that evaluate the availability, accessibility and regional interdependence of each resource in the water–energy–food nexus. This new index considers the Gross Domestic Product per capita and the involved population. As a case study, the 32 states of Mexico were considered to assess the effects of the COVID-19 pandemic on the economy and the security of the water-energy-food nexus at the state level. For this, the composite index was evaluated in the years 2019 and 2020. The results show that from 2019 to 2020, the value of the global index increased in 13 states, in 21 states the security index of the WEF nexus increased, and in 9 states the GDP per capita index increased. On the other hand, the results indicate that in 11 states there was no improvement in the nexus security index due to the increase in water demand, which considerably affected the water availability indicator.Supplementary InformationThe online version contains supplementary material available at 10.1007/s10668-022-02671-2.

Identifying rainwater harvesting sites using integrated GIS and a multi-criteria evaluation approach in semi-arid areas of Ethiopia

In recent years, East Africa has been suffering from severe droughts. The availability of water is crucial to socioeconomic development and ecosystem services in the region. In order to address the pressing issue of water scarcity in the Wag Himra zone, a study will identify viable rainwater harvesting (RWH) sites. Geographical Information System with a multi-criteria evaluation system was used to identify suitable RWH sites based on land use and cover, soil texture, runoff depth, slope, drainage density, and considering road and town constraints. The runoff depth was estimated using the soil conservation service curve number model, and the land use/cover image classification was undertaken using ArcGIS. By using weighted overlay analysis, sites that are potentially suitable for RWH were identified. Based on the hydrological and socioeconomic characteristics of the study area and available literature, the weight of the criteria was determined using the Analytical Hierarchical Process. The findings of the study indicate that only 0.02% of the study area is considered highly suitable, 2.59, 12.26, 61.76, and 21.1% are rated as moderately suitable, marginally suitable, less suitable, and not suitable for RWH, respectively, and 2.29% is labeled a constraint for RWH. It is possible to harvest and store rainwater in the study area to meet increasing water demand. These findings aim to assist decision-makers, planners, and managers to find sites, invest in water resources, and use RWH as an alternative water source.