Capita Water Consumption Research Articles

Mexico city’s decline in per capita domestic water use: a comprehensive spatial-temporal study

ABSTRACT Facing the growing challenges in water supply in urban areas, characterized by high demand and water scarcity, Mexico City, with its high population density and limited water resources, exemplifies the challenges in ensuring equitable management and water supply in complex urban environments. This study combines GIS tools, statistical analysis and spatial regression to analyze the spatiotemporal changes in per capita water consumption in Mexico City households between 2010 and 2019. The results show a 40% decrease in average consumption and a spatial reconfiguration that reflects an increase in inequalities in access to drinking water. The influence of five key factors in the reconfiguration is identified: intermittent supply, economic income, water feasibility, households without piped water, and an increase in dwellings. The findings are essential for developing equitable and effective water policies, emphasizing the need to address inequalities in water access in urban planning to achieve the Sustainable Development Goals.

Determination of Average Water Demand and Diurnal Consumption Pattern for a Multifamily Apartment Complex in Peshawar

Abstract: Accurately estimating and understanding domestic water demand and consumption patterns is essential for the efficient planning and management of drinking water supply systems. Traditional methods for estimating water demand are labor-intensive and often rely on assumptions. To overcome these limitations, this study employed a novel approach using highprecision data loggers to monitor water levels continuously in rooftop tanks at 5-minute intervals within a residential apartment complex in Peshawar, Pakistan. The findings indicate that per capita water consumption varies between 97 and 209 liters per capita per day (lpcd), with an average consumption of 173 lpcd. This methodology offers enhanced accuracy in quantifying water usage, providing a robust alternative to conventional estimation techniques.

Assessing the water metabolism of coastal urban areas based on the water mass balance framework across time periods: A case study of Cape Town, South Africa

The status of water resources in many coastal cities has become increasingly fragile. In a changing climate, the amount and intensity of rainfall have continued to decline, causing some coastal regions to experience severe drought and deteriorated water supply situation. This article presents a comprehensive study of the urban water metabolism of Cape Town, South Africa. A water mass balance framework was utilized to examine the city's water system across four distinct periods. In addition, the water-energy nexus before and after the drought crisis was evaluated. The key findings include a large amount of surface runoff in the Cape Town area that was not utilized before the drought crisis, resulting in a natural loss potential of water supply that is 2.54 times greater than water used for supply systems. During the drought, per capita water consumption dropped by a substantial 25%; at the same time, the total rate of water loss experienced a substantial decrease of approximately 21%. Since the pandemic, Cape Town's water resources policy has shifted to diversifying water sources, and the use of wastewater and natural water losses will be optimized by more than 32% in 2040 to achieve a water-sensitive city. Future research should explore the temporal and spatial dynamics of urban water flows, the impact of socioeconomic factors, and the integration of water system optimization models for enhanced urban water management.

Water scarcity and its implications on sanitation: A perspective study in an emerging city in Northern Ghana

Water scarcity is a critical global challenge affecting billions of people, particularly in developing regions like sub-Saharan Africa. In Ghana, this issue has become increasingly pronounced, with limited access to clean and safe water posing serious threats to the health and livelihoods of many communities. This study investigated the intricate relationship between water scarcity and accessibility, and the associated implications on sanitation practices in Damongo, a newly created regional capital and an emerging city. The study showed that the area faced evident water scarcity, with a daily per capita water consumption as low as 0.128 m3. Mechanized boreholes emerged as potential solutions, particularly for the 61.2% of respondents experiencing waiting times exceeding 15 min. The economic repercussions were noteworthy, as high water costs impacted livelihoods, emphasizing the need for policy interventions, especially for low-income households. Sanitation challenges are widespread, with 62.8% relying on pit latrines, and 56.1% lacking proper infrastructure. Water and sanitation-related diseases like typhoid and diarrhoea highlight the need for urgent interventions to enhance water quality and sanitation practices. Household water infrastructure analysis revealed diverse, primarily privately owned sources. Gender imbalances persist in water-fetching responsibilities, with 58.2% relying solely on females. Domestic water sources predominantly involved traditional options, potentially exposing residents to unsafe practices. Sanitation maintenance practices and intervals varied, signaling the necessity for comprehensive solutions. Households without toilets resorted to open spaces (43.6%), gutters (29.1%), and public toilets (12.7%), indicating challenges in waste disposal and sanitation facility access. Insights on the health dimension considered uncovering the prevalence of the top five water and sanitation-related diseases for 2022. These included typhoid (24.3%), diarrhoea (30.0%), Cholera (11.7%), Dysentery (14.6%), and Hepatitis (19.3%). These findings suggest the pressing need for improved sanitation and clean water access, as inadequate infrastructure and water scarcity contribute significantly to these health challenges.

Consumption Feedback and Water Saving: A Field Intervention Evaluation in the Metropolitan Area of Milan

This paper investigates whether informative feedback on consumption can nudge water saving. We launched a five-month online information campaign which involved around 1,000 households located in the province of Milan (Italy) with a smart meter. A group of households received monthly reports via email on their per capita daily average water consumption, including a social comparison component. The Intention to Treat (ITT) analysis shows that, compared to a benchmark group, the units exposed to the intervention reduced their per capita water consumption by around 6% (25.8 liters per day or 6.8 gallons). Being able to observe the email opening rate, we find that the ITT effect is mainly driven by complying units. Through an Instrumental Variable approach, we estimated a Local Average Treatment Effect equal to 54.9 liters per day of water saving. A further Regression Discontinuity Design analysis shows that different feedback on consumption class size differentially affected water saving at the margin. We also found that the additional water saving increased with the number of monthly reports, though it did not persist two months after the campaign expired.

Shortage Analysis and Strategies for the Water Resource in Saudi Arabia under the Rapid Development of the Tourism Industry

This study evaluates water sustainability in Saudi Arabia amid expanding tourism using a mixed-methods approach. Primary data were collected through surveys targeting 150 stakeholders in water management and tourism, while secondary data were sourced from official reports. Quantitative analysis revealed significant challenges, with an average daily per capita water consumption of 299 liters and severe stress in regions like Riyadh and Jeddah. Groundwater quantity for 2022 was recorded at 1.48 km³, and desalinated water production totaled 1.95 km³, revealing a supply-demand gap of 1.82 km³. The correlation analysis indicated a significant positive relationship (r=0.440) between tourism growth and water demand. Survey results showed 70% of respondents reported no difficulties in accessing clean water during Hajj, while 30% indicated occasional issues. Stakeholders emphasized the need for integrating renewable energy with desalination to reduce operational costs and carbon emissions. The study recommends enhancing Reverse Osmosis (RO) technology with solar energy to improve sustainability and efficiency, aligning with Saudi Arabia's Vision 2030. These findings highlight the necessity for sustainable water management strategies to balance economic growth with resource sustainability, guiding policymakers in developing effective practices for future water security.

Analysis to determine the domestic water usage in Yolde - Pate Area of Yola South Local Government Area of Adamawa State Nigeria

This research study presents findings of the analysis of determining the domestic water usage in Yolde-Pate area of Yola South LGA of Adamawa State Nigeria. During the recce survey and final survey; the sources of domestic water were identified and mapped out in the study area which include: 127 Industrial borehole, 16 hand-pumps, 6 well water and 1 public tap. Domestic water usage moves in hand with its source and accessibility this is where Nearest Neighbor Analysis NNA was used and its summary depicts the following; z-score of 0.205792265731; which means the pattern does not appear to be significantly different than random; which is fairly recommendable. Mean Distance is 51.1643 Meters, Neighbor Ratio is 1.024, and p-value: 0.836953. This was achieved due to the highly precision DGPS used in determining the spatial positions of each of the 150 XYZ points of each water source location and digitally mapping out the whole study area. Then 600 well-structured questionnaires that were randomly distributed within the study area with the respondent’s responses largely related to the analysis of determining domestic water usage were retrieved and analyzed with the End User Analysis (EUA)Technique. The results show that the total volume of water used daily per house ranges from 52,247 to 78,856 liters for each house hold with a range of 54.53liters to 67.69 liters of water consumption per individual in a day; which fall short of WHO standard of 120 liters. However the EUA based on the population density of the study area reveals: first for the high density areas, which has 3 wards Gadawalowol Yolde Patte ward, Jalingo Yolde Patte ward and Chaka Midari ward with a mean population of 1187, mean household size of 4.67 individuals, 71500 liters as the mean total of consume water daily, 60.35 as the mean per capita water consumption per day individually while standard still remains 120 liters and the mean total of daily demand is 142,440 liters; which shows deficit of what is needed. For the medium density areas with an average population of 1093 which are made up of 2 wards depicts 61100 liters as the mean total of water consumed daily by each household, 55.86 liters was consumed by an individual with a daily mean demand of 131,160 liters. While the low-density areas which mainly is occupied by the Sabonpegi Yolde Patte ward residence has a population of 876, total water consumption per household of 52,247liters, Per Capita Water Consumption (liters per day) is 59,64liters while its water daily demand is 105 120 liters; similarly, a shortage of what is demanded and WHO standard exist also in the medium and low-density areas. Recommendations were then spelt out to improve water consumption and usage with well design accessibility structure to improve well-being of the people in this study area.

Evaluation and forecasting of water cycle health in the yangtze river economic belt using composite weight and extensible cloud model

The regional water cycle reflects the dual processes of nature and society. A healthy and benign water cycle is a fundamental guarantee for achieving regional sustainable development.The Yangtze River Economic Belt, as a densely populated urban cluster with abundant water resources in China, plays a crucial role in promoting the sustainable development of Chinese urban clusters. It is of significant importance to optimize the water cycle health of the Yangtze River Economic Belt and explore its primary obstacles.This study integrates the natural-social attributes of the water cycle and selects 25 evaluation indicators from six dimensions: Drivers (D), Pressures (P), States (S), Impacts (I), Responses (R), and Management (M), to construct the water cycle evaluation system for the Yangtze River Economic Belt.Combining Analytic Hierarchy Process (AHP), Decision-Making Trial and Evaluation Laboratory (DEMATEL), and the Criteria Importance Through Intercriteria Correlation (CRITIC) method, the comprehensive weights of subjective and objective factors are obtained based on the principle of minimum relative entropy.Based on this, an Extended Cloud Model is constructed to evaluate the water cycle health status of the region from 2012 to 2022.Furthermore, the Obstacle Degree Model is introduced to identify the primary obstacles affecting the water cycle health in the region. Finally, the ARIMA model is applied to forecast the water cycle health status in the region from 2023 to 2030.The results indicate that the comprehensive water cycle health level in the region improved gradually from initially sub-pathological to sub-healthy status from 2012 to 2022.Per capita GDP, industrial water consumption per ten thousand yuan of industrial value added, per capita water consumption, forest coverage rate, sediment transport module, proportion of environmental protection investment to GDP, and proportion of water resources management investment to GDP are the primary obstacles affecting the improvement of health in this region.The forecast indicates that the overall water cycle health status in the region will remain at a sub-healthy level from 2023 to 2030.The research results can provide a scientific reference for further promoting the high-quality development of the Yangtze River Economic Belt, better supporting and serving China's modernization, and providing scientific reference basis.

Water Footprint Assessment and Virtual Water Trade in the Globally Most Water-Stressed Country, Qatar

Qatar is a severely water-stressed country. Despite Qatar’s aridity and its lack of freshwater resources, its per capita water consumption is one of the highest in the world, and it is expected to increase in the coming decades. Therefore, understanding water consumption and use through space and time becomes paramount. By employing water footprint assessment (WF) and analysis of virtual water trade (VWT), this research comprehensively examines Qatar’s water consumption patterns both domestically and internationally on a sectorial level (agricultural, industrial and urban sectors) between 2010 and 2021. The findings show that, internally, the urban sector contributed the most to the WF, followed by the industrial and the agricultural sectors with an annual average WF of 3250, 1650, and 50 million m3/y, respectively. Although Qatar exports large amounts of VW (1450 million m3/y), its VW imports (7530 million m3/y) are very high, reflecting the country’s agricultural demand, making Qatar a net VW importing country. Qatar exhibits a national WF of consumption of 11,900 million m3/y, with a water dependency index of 56% and a self-sufficiency index of 44%. Additionally, Qatar has a significant water export fraction of 20%, while only 3% of its water consumption relies on its natural resources. This study pinpoints sectors and areas where WFs can be reduced; the outcomes serve as a foundation for strategic planning, enabling Qatar to make informed decisions to optimize its water resources, enhance water use efficiency, and secure a sustainable water future in the face of escalating water stress. This study’s methodology and findings not only pave the way for more efficient water resource management in Qatar, but also offer a replicable framework for other arid and semi-arid countries to assess and optimize their water footprint and virtual water trade, contributing significantly to global efforts in sustainable water use.

Seasonal Variations in Household Water Use, Microbiological Water Quality, and Challenges to the Provision of Adequate Drinking Water: A Case of Peri-urban and Informal Settlements of Hosanna Town, Southern Ethiopia.

Several studies have been conducted on household water use and microbial water quality globally. However, studies that considered seasonal variability of household water use and microbial water quality were limited. Therefore, this study investigated the seasonal variability of household water use, microbiological water quality, and challenges to the provision of adequate water in the peri-urban and informal settlements of Hosanna town, Southern Ethiopia. A longitudinal study was conducted on 288 households. The data was gathered using a pretested structured questionnaire, laboratory-analysis, interviews, storage-container inventories, focus group discussions, key-informant interviews, and an observational checklist. The data was analyzed using stepwise-multiple linear regression, bivariate and multivariable logistic regression, thematic-analysis, t-tests, and non-parametric-tests. Households were visited for 7 consecutive days during the dry and rainy seasons to account for changes in daily and seasonal variation of water use. 440 stored water and 12 source samples were analyzed for E. coli presence during dry and rainy seasons. The prevalence of stored water contamination with E. coli was 43.2% and 34.5% during the dry and rainy seasons, respectively. The per capita water consumption was 19.4 and 20.3 l during the dry and rainy seasons, respectively. Piped water on-premises, small family size, volume, and number of water storage containers were significant predictors of per capita water consumption in both seasons. Piped water off-premises, storing water for more than 3 days, uncovered, and wide-mouthed water storage containers were significantly associated with the presence of E. coli in water in both seasons. Seasonal variability of household water use and microbiological water quality was statistically significant, which is a significant public health concern and needs intervention to enhance water quantity and quality to mitigate the risk of waterborne diseases. Findings also suggest seasonal monitoring of the safety of drinking water to ensure that the water is safe and healthy.

A segmentation approach to understanding water consumption behavioral patterns among households in Saudi Arabia for a sustainable future

Urban water consumption has significant implications for both human welfare and the environment, especially in arid regions. In Saudi Arabia, where 60% of the urban water supply relies on energy-intensive desalination processes, the average per capita water consumption rate of 300 L/day is one of the highest worldwide. This study investigates potential behavioral patterns in residential water consumption among households in Saudi Arabia. A segmentation approach is employed to classify residents into clusters and evaluate their potential water consumption behavioral patterns. Data from 618 households were collected via a structured questionnaire and analyzed using descriptive statistics, principal component analysis (PCA), and cluster analysis (CA). Participants were categorized into six segments based on the relationship between their behaviors and water consumption derived from the factor analysis. The outcomes of PCA and CA analyses indicate a relationship between respondents’ socio-demographic factors and their potential behavioral patterns in residential water consumption. The findings highlight that education, household size, income, housing type, age, and nationality, in increasing order of significance, are the key factors influencing household water consumption and conservation tendencies. The paper concludes that comprehending residential water consumption patterns is crucial for effective interventions, social marketing strategies, and communication campaigns for behavioral changes. The study can inform water conservation policies and programs that promote sustainable water consumption practices, benefiting agencies, policymakers, and scholars in the water sector.

Population Growth and Water Consumption: Chachapoyas Case, 2011 - 2021

Objective: The present research aims to evaluate the impact of population growth on the consumption of drinking water in the city of Chachapoyas during the period from 2022 to 2021 and project the trend until the year 2050. Method: The research followed a mixed longitudinal approach of basic study, with a non-experimental design, involving descriptive, explanatory, and correlational analyses. Based on 11 yearly observations (2011-2021), data from the Municipal Company of Drinking Water and Sewerage Services (EMUSAP) were used for a 20-year projection in Chachapoyas. Result: The results showcase Chachapoyas as an oasis amid the scarcity of drinking water. 96% of water consumption is concentrated in households, while 4% is attributed to the commercial and social sector. The 21% increase in water demand poses a challenge due to population growth and reduced water availability at collection centers. It is projected that per capita water consumption will decline to 1m3 per person by 2049. The relationship between population growth and water availability is critical, necessitating efficient resource management to ensure adequate water access in the future. Conclusion: Authorities should focus on implementing a circular economy, wastewater reuse, and improving pipeline distribution, all of which are critical components for sustainable water management in the city of Chachapoyas.

Developing a sustainable water conservation strategy for Saudi Arabian cities

Water scarcity is a global issue posing significant challenges for sustainable water management. Saudi Arabia, due to its arid conditions, limited freshwater resources, and high evapotranspiration rates, faces water scarcity. Factors such as rapid population growth, urban expansion, industrial development, and unsustainable water management practices contribute to increased municipal water demand and per capita water consumption. This trend is evident in the Jubail Industrial City (JIC), the largest industrial city in the Middle East. Although JIC heavily relies on desalination and groundwater extraction to meet growing water needs, it lacks a strategic vision for water conservation. The objective of this paper is to identify the causes of water scarcity, assess the sustainability of current water management practices, and develop a sustainable water conservation strategy using JIC as a case study. The study adopts a mixed-method approach, involving a comprehensive review of literature and official documents, along with an analysis of successful case studies of water conservation practices in arid regions worldwide. The proposed strategy encompasses demand management, adoption of water-efficient technologies, water reuse and recycling, public awareness and education, and policy and governance frameworks. Strategic water conservation, optimization and reuse hold significant relevance to industry settings. The study’s findings can contribute to the enhancement of the municipal water supply sector and support decision-makers in achieving the sustainable water resource management goals outlined in Saudi Vision 2030.

Spatial pattern and driving forces of regional water use efficiency: From spatial spillover and heterogeneity perspective

AbstractWater use efficiency (WUE) is critical for conserving water resources and protecting the environment, yet the lack of quantitative analysis of its spatial spillover effects and the spatial heterogeneity of its influencing factors hinders improving and achieving the spatial equilibrium regulation of regional WUE. In the current study, a way is proposed to explore the spatial pattern and driving forces of regional WUE from spatial spillover and heterogeneity perspective, in which the Improved Super‐slack‐based Model is firstly applied to estimate the WUE, and then, the spatial Markov chain and the geographically and temporally weighted regression model were, respectively, used to explore the spatial spillover effects of WUE and reveal the spatial heterogeneity of the driving forces behind the WUE. Guangdong Province, a region with rapidly developing economy and significant uneven development in China, was chosen as a case study. Results show that there is a radial pattern of high WUE in the Pearl River Delta and there are significant spatial spillover effects among cities, the city with higher WUE exerted positive effects on its neighboring city's WUE. The key driving factors of WUE include per capita GDP, per capita water consumption, proportion of secondary and tertiary industry water use, foreign direct investment, and R&D input, with spatial heterogeneity in their influences. Policies such as enhancing public awareness of water saving, increasing the reuse of wastewater in industrial parks, and promoting the inter‐municipal socioeconomic and technological exchanges are recommended to achieve a more coordinated and balanced regional WUE. The results of this study have scientific and practical implications for coordinating regional water resources exploitation and sustainable development.

Biological-Activity-Based Prioritization of Antidepressants in Wastewater in England and Japan.

Antidepressants are one of the most commonly prescribed pharmaceuticals. Although they have been frequently detected in aquatic environments around the globe, little is known regarding their adverse effects on humans and aquatic organisms. Recently, an in vitro monoamine transporter inhibition assay was developed to detect transporter-inhibitory activities of antidepressants in wastewater in Japan. However, it was unclear which antidepressants were responsible for transporter-inhibitory activities in wastewater. Herein, the per capita consumption of 32 antidepressants, their excretion of unchanged parent compounds, per capita water consumption, removal rate during wastewater treatment processes, and potency values from the monoamine transporter inhibition assay were used to prioritize antidepressants of concern in effluent wastewater in England and Japan. In both countries, sertraline and O-desmethylvenlafaxine had the highest contribution to inhibitory activities against the human serotonin transporter (hSERT) and zebrafish SERT (zSERT), respectively. It was found that the antidepressants inhibited the zSERT more strongly than the hSERT. The inhibitory activities found against the zSERT in wastewater in England and Japan were higher than thresholds for abnormal behavior in fish. The antidepressants prioritized in this study provide insight into launching environmental monitoring and ecotoxicological studies of antidepressants.

Activity-Wise Residential Water Use Behaviour in Aizawl City, Mizoram, India

The aim of this paper is to understand the overall household water use behaviour and activity-wise water use patterns in Aizawl city, Mizoram (India). The study is conducted in Aizawl city among 15 Local Councils out of 83 Local Councils. The number of sample households selected from each of the sample Local Councils are 50 households, thus data was gathered via questionnaire administered to 750 respondents’ mainly female household heads. The water consumption in the study area is far lower than the norms laid down by Bureau of Indian Standards. Even, in comparison to other major cities in the country, the consumption is also far deficient. The average per capita water consumption is estimated at 46 lpcd. About 38.93 per cent of the households consume water below 40 lpcd, 19.89 per cent consume between 40 lpcd to 50 lpcd, and 41.20 per cent consume water above 50 lpcd. Some household activities, like washing clothes, bathing, use in toilets, and washing dishes and utensils are the most water consuming activities in the City under focus.

Effects of heat source type on the thermodynamic performance and economy of domestic hot water system

In this paper, a solar assisted air source heat pump (SA-ASHP) domestic hot water (DHW) system is designed and built, the thermal performance of the system and the effect of heat source type on the energy consumption and carbon emission are studied by simulation and experiment. The static investment payback period of transforming the auxiliary heat source from electric boiler (EB) to ASHP is determined by economic analysis. The results show that the coefficient of performance of SA-ASHP system (COPS) varies from 2.76 to 6.26 and the coefficient of performance of ASHP unit (COPH) varies from 2.62 to 3.93 throughout the year. In the four typical heat source hot water systems, the SA-ASHP system has the lowest energy consumption, operation cost and CO2 emission. Compared with the solar assisted electric boiler (SA-EB) system, the power consumption per unit hot water, per capita power consumption and per capita water consumption of the SA-ASHP system decreased significantly, while the average heat collection efficiency and solar fraction increase obviously. Based on the actual operation data and economic analysis, the static payback period and CO2 emission reduction of transforming a SA-EB system into a SA-ASHP system have been analysed.

Assessment of agricultural water resources carrying capacity and analysis of its spatio-temporal variation in Henan Province, China

With the rapid development of global economy and society, water shortage has become a crucial limitation to the growth of many cities. The agricultural water resources carrying capacity (AWRCC) is a key indicator to judge the sustainable development of agriculture. It is necessary to quantificationally evaluate AWRCC to ensure safety of regional economic development and human being's living demand. To reasonably quantify AWRCC, this paper constructs an agricultural water resources evaluation system. CRITIC (CRiteria Importance Through Intercriteria Correlation) is introduced, and its combination with analytic hierarchy process (AHP) solves the subjectivity and randomness of weight determination. Based on the definition of AWRCC and fuzzy comprehensive evaluation (FCE), we construct support index (CCS), pressure index (CCP) and carrying capacity index (CCI) to describe the spatio-temporal variation of AWRCC in Henan Province. Applying sensitivity and correlation analyses into the AWRCC evaluation demonstrates practicality and rationality of results. It eventually provides corresponding suggestions to each city group with diverse carrying capacities. Main conclusions are as follow: (1) The per capita water consumption and agricultural water utilization rate in Henan trended to decrease yearly. The irrigation rate of cropland and the proportion of water-saving irrigation of cropland increased to a varying extent. Water resources utilization rate, cropland irrigation rate, proportion of water-saving irrigation in cropland, grain yield per unit cropland, and wetland proportion were relatively sensitive indicators and they were higher correlated with AWRCC. (2) During 2010–2020, although the agricultural water resources have been overloaded in Henan, AWRCC exhibited a slight enhancement on the temporal scale. On spatial scale, the central region had a stronger AWRCC than the surrounding cities, while the southwest region was relatively weaker, and the AWRCC of the eastern region continued to enhance. (3) According to the tertiary characteristics and spatio-temporal variation of AWRCC, cities of Henan can be roughly divided into four groups and some proposals were proposed individually to enhance the carrying capacity. The conclusion of this paper is helpful to understand the current situation of agricultural water resources in Henan and can provide a reference for the sustainable development of AWRCC.

Spatiotemporal Dynamics of Vegetation Index in an Oasis-Desert Transition Zone and Relationship with Environmental Factors

The oasis-desert transition zone (TZ) is an ecological buffer zone between a mobile desert and an oasis, which are important in reducing the forward mobility of sand dunes and wind and sand hazards in an oasis. In this study, the Dunhuang Oasis and its TZ in the Hexi Corridor (China) were examined. Based on the annual normalized vegetation index (NDVI) at each buffer distance of the TZ from 1987 to 2015, combing the watershed hydrology, oasis crop cultivation structure and industrial economic status, partial least squares regression models and a correlation analysis were used to examine the spatial and temporal changes in the vegetation gradient of the oasis TZ and the factors influencing those changes. (1) Spatially, the NDVI values in the TZ generally decreased gradually before stabilizing with a buffer distance (average decrease of 0.01–0.03 per 300 m). (2) Temporally, the mean values of the NDVI in the TZ show an overall wavelike variation across years. The annual average maximum NDVI value was 0.11 in 1987, whereas the annual average minimum value was 0.07 in 2014. (3) During the 1987–2015, runoff, tourist populations and water consumption for orchards were significantly and positively correlated with the NDVI; the year-end arable land area and the total industrial output value were significantly and negatively correlated with the NDVI; the rural per capita net income and water consumption for grain planting were not significantly and positively correlated with the NDVI; water consumption for the sum of vegetable and melon planting, water consumption for cotton planting, urbanization and rural populations were not significantly and negatively correlated with the NDVI. (4) The farm TZ NDVI is more strongly influenced by human activities than the undisturbed natural TZ.

Consumption feedback and water saving: An experiment in the metropolitan area of Milan

This paper questions whether informative feedback on consumption can nudge water saving behavioral change. For this purpose, we launched a five-month online information campaign which involved equipping around 1,000 households located in the province of Milan (Italy) with a smart meter. Treated households received monthly reports via email on their per capita daily average water consumption, which included a social comparison component (consumption class size). The difference-in-differences analysis showed that, compared to the control group, treated units reduced their daily per capita water consumption by more than 10 % (22 liters or 5.8 gallons). This additional water saving increased with the number of monthly reports, though it did not persist two months after the campaign expired. The impact of the campaign was heterogeneous across consumption classes, while a Regression Discontinuity Design analysis showed that different feedback on consumption class size differentially affected water saving at the margin. Finally, being able to observe the email opening rate, we complemented the ITT analysis by developing a Per Protocol (PP) analysis, where non-adherent units were excluded from the treated group. Both ITT and PP provide consistent conclusions, thus augmenting the level of confidence in the study results.