Reduce Water Use Research Articles

Irrigation water demand management with emphasis on pricing policy

Abstract Serious constraints in increasing water supply have led countries around the world to seek solutions for managing water demand. Proper pricing of water is one of the foremost water demand management policies which can lead to the optimal water use. On the flip side, the quality of agricultural water is declining due to the uncontrolled abstraction of groundwater. In this regard, the present study aims to determine the economic value of different qualities of water throughout pistachio-growing regions of the Rafsanjan-Anar plain in Iran. Results reveal that the economic value and price elasticity of water demand differ among different groups. Freshwater, moderately saline water and highly saline water have the highest to lowest elasticity and shadow price, respectively. Additionally, comparison of the gross margin, which represents the profit from each activity, in two conditions including the unsustainable status quo and sustainable conditions intended by the Ministry of Energy, shows that although water use has declined by 50%, the gross margin has decreased by only 36%. This implies it is feasible to reduce water use in pistachio orchards by water re-allocation with a minimum decline in profit, which will both reduce water use and ensure high economic benefits for farmers.

Comparative life cycle assessment of rainbow trout (Oncorhynchus mykiss) farming at two stocking densities in a low-tech aquaponic system

The present study assessed the effect of two fish stocking densities (Low, 3.81 kg m−3 vs High, 7.26 kg m−3) on the environmental footprint associated with the production of rainbow trout (Oncorhynchus mykiss) and lettuce (Lactuca sativa) in an experimental low-tech aquaponic system. A gate-to-gate and a cradle-to-gate Life Cycle Assessment models were used. The functional unit was 1 kg increase of table-size rainbow trout (about 330 g body weight). Mass allocation, economic allocation, and system expansion were applied to resolve the multifunctionality of the tested system. The impact categories assessed were global warming (GWP, kg CO2-eq), acidification (AP, g SO2-eq) and eutrophication (EP, g PO4-eq) potentials, cumulative energy demand (CED, MJ), freshwater ecotoxicity (ECO, CTUe), water depletion (WD, m3 water equivalent). In the gate-to-gate model, considering mass allocation, the production of 1 kg increase of rainbow trout emitted on average 8.8 kg CO2-eq (GWP), 56 g of SO2-eq (AP) and 64 g of PO4-eq (EP), while the CED was 161 MJ, the ECO was 186 CTUe, WD was 0.061 m3. Global warming, cumulative energy demand and freshwater ecotoxicity were the impact categories mostly affected by the changes in fish stocking density. A high density was associated with a lower environmental impact per kg of fish produced both considering the gate-to-gate and cradle-to-gate approaches. Electricity was the dominant contributor in all the impact categories, ranging from 64% of EP to 93% of ECO while feed production accounted for 19% of WD and 10% of GWP. The change of the energy source from a common grid mix to a photovoltaic system substantially reduced global warming whereas the improvement of feed conversion ratio decreased eutrophication potential. Based on life cycle assessment, the farming of rainbow trout in aquaponics is a promising alternative to common flow-through systems, particularly in view of reducing water use.

A novel cover material improves cooling energy and fertigation efficiency for glasshouse eggplant production

Glasshouses hold the potential to improve global food security, but high energy costs are an ongoing challenge in bringing them to the forefront of agriculture in warm climates. Here, the energy-saving potential of a ‘Smart Glass’ (SG), diffuse glass fitted with ULR-80 film which permits transmission of 85% of photosynthetically-active light and blocks heat-generating radiation, was characterised for a warm-climate glasshouse. Two consecutive 6-month trials of eggplant crops were grown in a high-tech glasshouse to compare SG to standard diffuse glass (control) in both cool and warm climate conditions. The SG reduced cooling energy use by 4.4% and fertigation demand by 29% in cooler months, and reduced cooling energy use by 4.4% and fertigation demand by 18% in warmer months. The SG did not significantly affect ventilation or heating energy use, but substantially reduced fruit yield. SG may be beneficial for reducing nutrient/water use alongside minor energy savings in commercial glasshouses. However, re-engineering the spectral characteristics of SG could improve eggplant fruit yield while maintaining reductions in energy, nutrient, and water use in the glasshouse.

Incorporation of novel foods in European diets can reduce global warming potential, water use and land use by over 80.

Global food systems face the challenge of providing healthy and adequate nutrition through sustainable means, which is exacerbated by climate change and increasing protein demand by the world's growing population. Recent advances in novel food production technologies demonstrate potential solutions for improving the sustainability of food systems. Yet, diet-level comparisons are lacking and are needed to fully understand the environmental impacts of incorporating novel foods in diets. Here we estimate the possible reductions in global warming potential, water use and land use by replacing animal-source foods with novel or plant-based foods in European diets. Using a linear programming model, we optimized omnivore, vegan and novel food diets for minimum environmental impacts with nutrition and feasible consumption constraints. Replacing animal-source foods in current diets with novel foods reduced all environmental impacts by over 80% and still met nutrition and feasible consumption constraints.

Nexus implementation of sustainable development goals (SDGs) for sustainable public sector buildings in Pakistan

The United Nations (UN) has introduced 17 Sustainable Development Goals (SDGs) intending to achieve a conventional trio of social, economic, and environmental prosperity across the world. Pakistan is making a fair contribution to SDG achievement under its ‘Vision 2025’. However, the introduced strategy for SDG implementation is a sectoral based approach which leads to severe resource inefficiency. The objective of this study is the development and implementation of a nexus strategy of SDG 6 (Clean Water and Sanitation), SDG 7 (Affordable and Clean Energy), SDG 11 (Sustainable Cities and Communities), and SDG 13 (Climate Action) in Pakistan due to their indepth interlinkage and interdependence, to achieve sustainability in Energy, Water, and Environment. This study comprises an onfield Energy-Water-Sustainability assessment of 24 public sector premises across Punjab to create a pilot model for future implementation. The Pearson correlation analysis of the SDGs substantiates the argument of the nexus approach. The results of this work show the energy conservation potential of approximately 12.8 MW and renewable energy installation potential of 40.4 MW to achieve SDG 7. Moreover, rainwater harvesting is calculated to be 0.035 million cm3 per annum, contributing to approximately 7% reduction in water use to achieve SDG 6 and minimizing the environmental impact on cities by reducing 14.8 million tons of Greenhouse Gases (GHGs) per annum to achieve SDG 11 and 13. The results show that due to indepth interlinkage, the nexus implementation approach enhances the execution process while eliminating resource duplication to reduce inefficiency.

Effect of information-driven irrigation scheduling on water use efficiency, nutrient leaching, greenhouse gas emission, and plant growth in South Florida

Irrigation, essential for food production and landscape maintenance, affects soil water dynamics, water quality, and soil chemistry. However, the multidimensional role of irrigation has not been a focus in irrigation sciences. We evaluated the performance of different irrigation scheduling methods regarding water saving, water quality protection, and greenhouse gas emission for improved irrigation sustainability. Plot-scale experiments with snap beans and turfgrass were conducted with four irrigation scheduling methods: two conventional practices and two information-driven approaches based on soil water sensing and modeling. The results showed that information-driven scheduling significantly reduced irrigation water use while maintaining the yield and biomass of snap beans and the health of turfgrass. The information-driven methods also reduced nutrient leaching into deeper soil layers. Greenhouse gas emissions were either below the detection limit or did not change between irrigation treatments. This study demonstrated that soil water sensing and modeling could improve the sustainability of irrigation by reducing water use and nutrient losses to the aquifer while maintaining agricultural productivity.

Measured and modeled maize and soybean growth and water use on pipeline disturbed land

Quantifying the impacts of soil disturbance on crop yield after installing an underground pipeline is essential for implementing effective mitigation plans and land restoration guidelines in agricultural systems. The objective of this study was to model maize and soybean yields on disturbed (subsurface pipeline installation areas) and adjacent undisturbed (control) land areas. Field observations and simulation results depicted the negative impacts of soil disturbance on soil physical, chemical, and hydrological properties. Grain yield and aboveground biomass losses up to 27% were observed in the pipeline disturbed area, where the soil profile had 15% lower plant-available water retention capacity than the undisturbed soil. APSIM was parameterized using two years (2019 and 2020) of in-season crop growth observations from a soybean-maize rotation system. Simulation of yield production was further evaluated against independent data from 2017 to 2018. The overall model performance was assessed using the index of modeling efficiency (EF). The model was effective in simulating aboveground biomass (EF disturbed-undisturbed: 0.96–0.98), grain yield (EF disturbed-undisturbed: 0.91–0.96), and soil water content in the 0–450 mm soil layer (EF disturbed-undisturbed: 0.84–0.86) for the parameterization dataset. Furthermore, the EF values for simulations of the independent yield data were also satisfactory (EF of 0.98 and 0.97 for disturbed and undisturbed soils, respectively). Soil disturbance reduced water use efficiency (WUE) by 25% and 30% in soybean and maize, respectively. This study indicated the suitability of using APSIM for simulating crop growth and yield production in the highly disturbed pipeline installation area.

Economic assessment of converting a pressurised water distribution network into an off-grid system supplied with solar photovoltaic energy

Converting a water pressurised distribution network into an off-grid pumping station supplied by solar photovoltaics represents a challenge for utility managers, user demand assessments evaluate the energy generated in a solar-powered systems to establish energy consumption. This work includes quantifying potential investments and economic savings that could be achieved, as well as the payback period which results as an indicator of the suitability of adapting to a power supply utilising solar panels. A tool (UAsolar) to aid practitioners has been developed, it requires a calibrated hydraulic model to account for the energy requirements in the water delivery process of pressurised networks. The authors encourage students, professionals, and decision-makers to use this tool to identify potential efficiency gains (e.g., delivery schedule, reduction of water use) and to synchronise energy production and consumption. Users can get results with low computational time using the software on six pressurised distribution networks. Practitioners should note that the irrigation networks have sized installations with a few photovoltaic modules, while in urban pressurised networks the results show larger installations are required. In addition, irrigation network managers can match energy demand with energy production by changing consumption over time, this could reduce the quantity of modules required and remove the need for energy storage. The payback period ranges from 6.08 to 13 years for the cases where the investment is recovered—(values that show that this investment yields a high return as the lifetime of the PV modules is 25 years). However, one municipality among those studied shows that in some scenarios it is not viable to convert networks into a standalone system.Graphical abstract

Performance of Drip and Mist Irrigation to Supply Water for Vegetable

Irrigation or water use for agriculture is the biggest water consumer. Reducing water use for irrigation means significantly to water saving. Drip and mist irrigations are methods of water application which consume water more efficiently and more agriculture products produce from same amount of water. This research aimed to assess performance off drip irrigation and mist irrigation to supply irrigation water for vegetables. The vegetables cultivated were spinach, mustard, and water spinach. The indicators employed were discharge, uniformity, dan water productivity. The research results showed that average discharges of drip and mist irrigations were 0.0056 litre/second and 0.0012 litre/second, respectively. The uniformity was measured using distribution uniformity (DU) and Christiansen uniformity index (CU). The DU of drip and mist irrigations were 0.84 and 0.76, respectively. The CU of drip and mist irrigations were 0.76 and 0.82, respectively. The biomass water productivities of spinach, mustard, and water spinach irrigated with drip irrigation were 2.23, 9.51, and 7.92, respectively. The biomass water productivities of spinach, mustard, and water spinach irrigated with mist irrigation were 0.98, 8.70, and 9.10, respectively.

Exploiting IoT and Its Enabled Technologies for Irrigation Needs in Agriculture

The increase in population growth and demand is rapidly depleting natural resources. Irrigation plays a vital role in the productivity and growth of agriculture, consuming no less than 75% of fresh water utilization globally. Irrigation, being the largest consumer of water across the globe, needs refinements in its process, and because it is implemented by individuals (farmers), the use of water for irrigation is not effective. To enhance irrigation management, farmers need to keep track of information such as soil type, climatic conditions, available water resources, soil pH, soil nutrients, and soil moisture to make decisions that resolve or prevent agricultural complexity. Irrigation, a data-driven technology, requires the integration of emerging technologies and modern methodologies to provide solutions to the complex problems faced by agriculture. The paper is an overview of IoT-enabled modern technologies through which irrigation management can be elevated. This paper presents the evolution of irrigation and IoT, factors to be considered for effective irrigation, the need for effective irrigation optimization, and how dynamic irrigation optimization would help reduce water use. The paper also discusses the different IoT architecture and deployment models, sensors, and controllers used in the agriculture field, available cloud platforms for IoT, prominent tools or software used for irrigation scheduling and water need prediction, and machine learning and neural network models for irrigation. Convergence of the tools, technologies and approaches helps in the development of better irrigation management applications. Access to real-time data, such as weather, plant and soil data, must be enhanced for the development of effective irrigation management applications.

Amplified warming induced by large-scale application of water-saving techniques

Large-scale agricultural activities can exacerbate global climate change. In the past three decades, over 5 Mha of cultivated land have been equipped with water-saving techniques (WSTs) in Northwest China to cope with water scarcity. However, the effect of WSTs on local climate and its mechanisms are not yet understood. Here, we have quantified the local climatic effect by comparing temperature and humidity at controlled and irrigated sites before and after the large-scale implementation of WST. Results show that the substantial reduction in irrigation water use has led to an average increase of 0.3 °C in growing-season temperature and reduced relative humidity by 2%. Near-surface air temperature responds nonlinearly to percentage area of WST and a threshold value of 40% is found before any noticeable warming effect over the study area. Moreover, it is found that regions with relatively humid climates respond more significantly to WST. This study reveals the mechanism of WST on near-surface climate and highlights the importance of incorporating this feedback into sustainable water management and land-surface models for assessing the impact of irrigated agriculture on regional climate change.

Non-water factors in water governance and their implications for water sustainability: The case of Ontario’s water use reduction policy

Despite longstanding interest in reducing water use in Ontario, Canada’s most populous province, public policy responses have tended to be restricted to the water sector’s traditional remit, e.g., improving public access to water data. However, it is not clear that these type of measures will be enough to address concerns over water quantity and advance water sustainability, as they are tied to other socio-economic concerns, external to the water sector. The purpose of this study is to understand the range of external factors that influenced the development and implementation of the water use reduction (WUR) policy in Ontario, and to identify opportunities for harnessing these factors to advance WUR objectives. To do so, we propose a diagnostic framework that maps external factors in relation to a specific water governance situation. We carried out 13 semi-structured interviews and reviewed 56 documents. We combined deductive and inductive approaches to content analysis. We found many non-water factors influencing the governance of WUR in Ontario. Particularly, the economic development provincial objective strongly shaped Ontario’s WUR policy by influencing the adoption of a demand management approach centering on water efficiency, rather than conservation. Furthermore, the WUR policy primarily serves the economic development objective. An implication is that water policies can be used instrumentally, raising the question of what constitutes a “water policy”. In summary, this study argues that non-water factors can thus influence our path to water sustainability, in this case represented by the water conservation approach, by defining an enabling (or hindering), institutional framework.

Environmental behavior practice in government agencies: Evidence from Kingdom of Saudi Arabia

Environmental behavior (EB) is a kind of organizational behavior that seeks to protect the natural environment and conserve resources, such as saving energy, recycling wastes, duplex printing, reducing water use, non-smoking in the workplace, and designing environmentally friendly products. This study aims to identify the degree of environmental behavior practice and examine its constraints in Saudi government agencies. This study is based on a single design of cross-sectional research. 436 responses were collected from employees of government agencies in Saudi Arabia. The study results indicated that the EB practice is generally high in government agencies.Furthermore, the results revealed that female employees in government agencies have no statistical difference from male employees. In other words, the EB practice of men and women in government agencies is equal. The study also found a significant difference between married, unmarried, and divorced groups. Divorced employees report a higher level of EB than other employee groups. However, the study indicated a significant difference between the high school, graduate, and postgraduate groups. In other words, employees with high school education have a higher level of EB. Receiving and not receiving leadership support have a significant difference, whereas employees who received environmental training reported higher levels of EB than others. The outcomes also indicated a difference between the group of employees who have religious values. The outcomes of this study may be of benefit to researchers, regulators, policymakers, managers, and governors. AcknowledgmentThe author thanks the Deanship of Scientific Research at King Saud University for supporting this study.

Coca-Cola’s Cape Town Crisis: Examining Companies’ Water Rights Obligations in a Changing Climate

While Coca-Cola portrays itself as a ‘water neutrality’ leader, its failures during Cape Town’s water crisis exemplify the changing nature of corporate human rights obligations in the face of climate change. Between 2015 and 2018, drought conditions plunged Cape Town into a crisis, leading to increasingly strict household water restrictions and depriving families of their constitutionally guaranteed water allowance.1 However, in December 2017, when Cape Town officials called for a 45% reduction in commercial water use, Coca-Cola’s local independent bottler – Coca-Cola Peninsula Beverages (CCPB) – refused to reduce its 44 million-litre monthly withdrawals.2 The city subjected households to water restrictions and price increases up to 556%, while businesses only saw a 104% price increase with no consumption restrictions.3

Effects of Light Spectral Quality on Photosynthetic Activity, Biomass Production, and Carbon Isotope Fractionation in Lettuce, Lactuca sativa L., Plants.

The optimization of plant-specific LED lighting protocols for indoor plant growing systems needs both basic and applied research. Experiments with lettuce, Lactuca sativa L., plants using artificial lighting based on narrow-band LEDs were carried out in a controlled environment. We investigated plant responses to the exclusion of certain spectral ranges of light in the region of photosynthetically active radiation (PAR); in comparison, the responses to quasimonochromatic radiation in the red and blue regions were studied separately. The data on plant phenotyping, photosynthetic activity determination, and PAM fluorometry, indicating plant functional activity and stress responses to anomalous light environments, are presented. The study on carbon isotopic composition of photoassimilates in the diel cycle made it possible to characterize the balance of carboxylation and photorespiration processes in the leaves, using a previously developed oscillatory model of photosynthesis. Thus, the share of plant photorespiration (related to plant biomass enrichment with 13C) increased in response to red-light action, while blue light accelerated carboxylation (related to 12C enrichment). Blue light also reduced water use efficiency. These data are supported by the observations from the light environments missing distinct PAR spectrum regions. The fact that light of different wavelengths affects the isotopic composition of total carbon allowed us to elucidate the nature of its action on the organization of plant metabolism.

Flocculation of Clay-Based Tailings: Differences of Kaolin and Sodium Montmorillonite in Salt Medium.

Complex gangues and low-quality waters are a concern for the mining industries, particularly in water shortage areas, where the closure of hydric circuits and reduction in water use are essential to maintain the economic and environmental sustainability of mineral processing. This study analyzes the phenomena involved in the water recovery stage, such as sedimentation of clay-based tailings flocculated with anionic polyelectrolyte in industrial water and seawater. Flocculation–sedimentation batch tests were performed to ascertain the aggregate size distribution, the hindered settling rate, and the structure of flocs expressed through their fractal dimension and density. The aggregates’ properties were characterized by the Focused Beam Reflectance Measurement (FBRM) and Particle Vision Microscope (PVM) techniques. The impact of the type of water depends on the type of clay that constitutes the suspension. For quartz/kaolin, the highest performance was obtained in industrial water, with bigger aggregates and faster settling rates. However, the tailings composed of quartz/Na-montmorillonite reversed this trend. The type of water impacted the efficiency of primary-particle aggregation. The trials in industrial water generated a portion of non-flocculated particles, which was observed through a bimodal distribution in the unweighted chord-length distribution. This behavior was not observed in seawater, where a perceptible fraction of non-flocculated particles was not found. The additional cationic bonds that offer seawater favor finer primary-particle agglomeration for all tailings types.

Human Intervention Will Stabilize Groundwater Storage Across the North China Plain

AbstractThe North China Plain (NCP) has been subjected to groundwater overexploitation over the past decades as a result of rapid socioeconomic development and irrigation water demand with relatively limited renewable water resources. Operation of the middle route of the South‐to‐North Water Diversion Project (SNWD‐M) since December 2014 has provided an opportunity for groundwater sustainability in the NCP by increasing water supply and reducing groundwater abstraction. Water use changes have largely been driven by socioeconomic changes. However, impacts of water diversion, water use change, as well as climate variability in the future on groundwater storage (GWS) in the NCP have not been investigated. This study aims to simulate and project GWS in the NCP during 2005–2050 by incorporating effects of water diversion, water use, and climate variability. The high‐resolution Community Water Model with 30 arcsec spatial resolution was set up to assess interactions between water demand and availability by simulating surface water and groundwater abstraction dynamically. Results show that water diversion and reductions in water use may increase GWS over the NCP in 2050 by 144 mm (19 km3) and 573 mm (75 km3), respectively. Evaluation of GWS among different scenarios shows that combinations of factors, including water use reductions, water diversion, and precipitation variability can contribute up to 73%, 37%, and 32% to GWS stability, respectively. This study highlights the contributions of different management strategies toward sustainable GWS and the importance of water conservation along with diversions.

Seed mixture of oats and common vetch on fertilizer and water-use reduction in a semi-arid alpine region

The overuse of synthetic fertilizers damages terrestrial and aquatic ecosystems on the Tibetan plateau. We conducted this study to investigate the possibility of reducing fertilizer use by applying cereal-legume mixture planting in forage crops cultivation. A field experiment was conducted in 2017 and 2018 at Jintai farm in the northeast of the Tibetan plateau. The experiment was a randomized complete block design with four treatments: sole oat with nitrogen application rate of 120 kg ha−1, sole oat with a lower nitrogen rate of 60 kg ha−1, and oat and common vetch mixtures applied with those two nitrogen levels. Results showed that forage biomass production of oat-common vetch mixture was comparable or higher than that of corresponding sole oat under different nitrogen levels. Nitrogen uptake of the mixture was 19.6–81.7% higher than that of sole oat under high nitrogen fertilization and was 107.3–144.6% higher under low nitrogen. Biological nitrogen fixation of common vetch in mixture stands ranged from 11.1 to 59.1 kg ha−1. Nitrogen use efficiency in the mixture was lower than that in sole oat under both nitrogen levels. However, the partial factor productivity of applied nitrogen (PFPN) in the mixture was higher than that in sole oat. Mixture with low nitrogen application attained the highest PFPN of 102.8 and 150.6 kg kg−1 in 2017 and 2018 respectively. The mixture system depleted much more soil water storage than sole oat in both years. Water use efficiency based on biomass production in the sole and mixture systems were comparable. However, that based on crude protein production was far greater in the mixture system, and the advantage of the mixture under low nitrogen level was more significant compared to that under high nitrogen level. Therefore, we conclude that practicing cereal-legume mixture planting in forage production could improve nitrogen and water use efficiencies, maintain forage production and improve forage quality. We suggest applying the mixture planting system and reducing the amount of nitrogen application in forage production in the semi-arid farming area on the Tibetan Plateau and similar alpine regions worldwide.

Selecting High-Impact Landscape Irrigation Conservation Behaviors: Formative Research to Inform Behavior-Change Efforts

Background This work addresses the increasing prevalence of water scarcity. Droughts are projected to worsen as a result of climate change and urbanization, increasing the need for all sectors to reduce the amount of water used. Home landscape irrigation represents an important opportunity to reduce water use in the United States. Focus of the Article This formative research study used social marketing techniques to estimate potential impact of irrigation water conservation behaviors, weight and prioritize the behaviors to guide behavior selection in the context of residential irrigation conservation. Research Objective The objectives were to estimate (1) the potential impact of, (2) current adoption levels and likelihood of adoption of, and to (3) prioritize various landscape irrigation water conservation behaviors. Program Design/Approach When addressing any issue, including water scarcity, identifying target behaviors is the first, foundational step for a successful social marketing campaign. This research focuses on formative social marketing research to inform local interventions designed to reduce the amount of water applied to residential yards across the United States. Importance to the Social Marketing Field This study outlines a process to compare and prioritize water conservation behaviors with the goal of reducing residential landscape irrigation usage. We demonstrate a technique for obtaining this type of formative research, the lack of which can serve as a barrier to change agents promoting behaviors in any context. Methods We employed a two-pronged quantitative survey research approach to collect technical experts’ impact ranking and U.S. residents’ current adoption levels and likelihood of adopting potential irrigation water conservation behaviors. The 14-member expert panel was selected using purposive and snowball sampling techniques, and the residential sample ( N = 2601) was recruited using purposive sampling. Results Mean weights ranged from −46.55 to 61.13. Singly considering impact, current adoption levels, or likelihood of adoption would result in a different behavior receiving priority for a campaign (eliminating irrigated areas in landscapes, installing smart irrigation controllers, and following local watering restrictions, respectively). However, when these values were considered together, installing drought-tolerant plants in the yard had the greatest overall weight. Limitations A possible conceptual limitation of this case study was the national scope of our research. The findings provide valuable baseline data for behavior change practitioners working across the country, and it is advisable to replicate this process at a local scale corresponding to the targeted intervention. Recommendations for Research or Practice The findings underscore the importance of including technical experts and target audience members early in social marketing program planning and reveal the importance of systematically approaching behavior change selection to thoroughly consider different components of potential behaviors. Behavior change practitioners working on water issues can use the weights reported here to prioritize behaviors for targeted interventions, and those working in all areas can follow the process to prioritize behaviors at the local level. There are exciting opportunities to decompose likelihood into behavioral antecedents for both research and application.

Crop calendar optimization for climate change adaptation in rice-based multiple cropping systems of India and Bangladesh

Adjusting crop calendars may present an effective adaptation measure to avoid crop yield loss and reduce water use in a changing climate. In order to better understand potentials and limitations of adjusting crop calendars for climate change adaptation of tropical multi-cropping systems with short fallow periods, we used a regionally calibrated Environmental Policy Integrated Climate (EPIC) agronomic model to estimate annual caloric yield and blue water requirement (BWR) of irrigated double-rice and rice-wheat cropping systems in India and Bangladesh. We adjusted crop calendars by (a) single-objective optimization to maximize annual caloric yield and (b) multi-objective optimization to minimize BWR under current and future climate scenarios, focusing on climatic drivers of optimal growing seasons. While the short time intervals between harvest of kharif crops and (trans-)planting of rabi crops limit the space for planting date shift in the study area, our results indicate that crop calendar adjustment has great potential to reverse yield loss induced by temperature rise and decrease BWR by utilizing monsoon precipitation. The study indicates a trend towards earlier planting of rabi wheat to mitigate heat stress during the reproductive stage. Moreover, earlier planting of kharif rice can help to utilize monsoon precipitation, avoid cold stress of kharif rice during anthesis, and allow for early wheat sowing during the historic period. By the 2080s, the increase of heat stress in summer and the decrease of cold stress in winter seems to allow more flexibility for late rice in kharif season, but a conflict between later planting for yield improvement and earlier planting for blue water saving is expected in kharif rice on the Indo-Gangetic plain of India and Bangladesh. Therefore, the trade-off between yield improvement and irrigation water use needs to be carefully considered to promote adaptive adjustment of crop calendars under climate change.