Reservoirs of hydropower plants have a significant impact on Water shortages as large amounts of Water evaporate from the surface of the reservoirs and become out of reach. This is a major issue in hydrology and Water resources, which results in the availability of Water resources. In this regard, the concept of Water Footprint was used to calculate the Water consumed in the process of generating electricity from these plants. In this study, to calculate the Water Footprint in electricity produced in hydropower plants of the country, data on the annual evaporation volume (m3) and annual electricity generation (m3/TJe) from 17 hydropower plants in Iran for the period of 2010 to 2017. The results showed that on average, the largest Water Footprint in electricity produced by Droudzan power plant was 287649 (m3 / TJe) and the lowest was related to Masjed Soleyman power plant and equal to 405 m3 / TJe. The average Water Footprint in electricity production from Iranian hydropower plants was estimated at 6132 (m3 / TJe).

Iran, is amongst the arid and semi-arid regions of the world, suffering from Blue Water scarcity. Hence, sustainable development in Iran requires modifying Blue Water consumption pattern, and on the other hand, all Water resources consumption planning requires a proper knowledge about the Water scarcity status in different regions of the country. In this study, for the first time, Water scarcity status is assessed based on the Blue Water scarcity index (BWS) under different temporal resolutions, including annual and monthly scales, and different spatial resolutions, including national, climate-regions, and provincial scales. In this regard, total Blue Water consumption was first estimated on a daily basis for different provinces over the period 2005-2015, and then was divided by Blue Water availability to estimate BWS. A BWS<1 indicates non-scarcity status, and 1≤, BWS<1. 5, 1. 5≤, BWS<2, and BWS> indicate, low, moderate, and severe Water scarcity, respectively. Every place or any time scale with BWS> is called a hotspot. Based on the annual assessment for the entire country 46% of total Blue Water consumption in the agricultural sector is unsustainable, and is consumed at the cost of violating environmental flow requirements,under such conditions, the BWS is 1. 9 and the entire country is under moderate Water scarcity. However, based on the annual assessments at finer spatial resolutions, the humid climatic region and 7 provinces do not experience Blue Water scarcity. Besides, there are non-hotspots for all considered spatial scales under monthly assessments. Based on the findings of this study, changing the resolution of the BWS assessments will change the number of hotspots in the range of 1 to 37, and will change the status of these hotspots as well. Hence, properly diagnosing the actual hotspots, in which environmental flow requirements are not satisfied due to unsustainable Blue Water consumption, requires assessments at the possible finest spatial and temporal scales.

Water Footprint index shows actual consumption of Water in three components: Blue, green and gray. Nowadays, the modern management of Water resources with integrated approach takes into account the concept of Water Footprint. In this research, wheat Water Footprint was evaluated at strategic zones with regards to Water resources (Blue Water, green Water and gray Water) and an optimal cropping pattern in different climates of Iran was presented. For this purpose, 33 provinces of the country were first classified according to the UNESCO cluster. All stations were classified in 6 climates; Plentiful Humidity Cool Warm (PH-C-W), Semi-Arid Cold Warm (SAK-W), Semi-Arid Cool Very Warm (SA-C-VW), Arid Cool Warm (A-C-W), Arid Mild Warm (A-M-W), Arid Cool Very Warm (A-C-VW). Then the Water Footprint was calculated and evaluated in each climate for all three components as Blue, green and gray Water. The results showed that the highest amounts of Blue Water Footprint are seen in the central and southern parts of Iran. The highest amounts of green Water Footprint was seen in the northern and western parts and the maximum gray Water Footprint was for the southern parts of the country. The average of green, Blue and gray Water Footprints was obtained respectively as 503. 3, 1392. 8 and 286. 2 m3/ton over the country. The results showed that wheat crop cultivation was not recommended in A-C-W and A-CVW climate zones of Iran.

Objectives: After wheat, rice has the most important role in human nutrition. Despite the vital importance of its cultivation, high Water consumption and Water shortage crisis, the sustainability of the cultivation of this grain has faced many problems. Therefore, the purpose of this study is to investigate the Water Footprint and Water use efficiency of rice among the provinces in order to move towards crop sustainability. Methods & Materials: In this study, Water Footprint index was used to calculate Water use efficiency in rice production. For this purpose, first the Water Footprint components for the provinces of the country were calculated and then the Water use efficiency was calculated. Results: The results of calculating Water Footprint showed that the lowest Water Footprint is related to Mazandaran and Gilan provinces and the highest Water Footprint is related to South Khorasan and Sistan & Baluchestan provinces. Also, the highest and lowest amount of green Water Footprint is related to Gilan and South Khorasan province, respectively. The results of Water use efficiency calculation showed that Mazandaran (0. 511) and Gilan (0. 422) had the highest efficiency and South Khorasan (0. 135) and Sistan & Baluchestan (0. 171) had the lowest efficiency. Conclusion: By comparing the Water Footprint components among the provinces of the country, it is cleared that the ratio of Blue, green and grey Water Footprint in total Water Footprint is 45-53%, 6-25% and 0-15%, respectively. Also, the total Water Footprint of the country was obtained in the range of 1958 and 2758 m3 per ton.

The rapid growth of global population has placed an immense stress on the demand of natural resources and contributes to the destruction of the natural environment. As the planet is now consuming natural resources in the production of goods and services faster than the environment can regenerate, strategies are urgently required to manage the ecological assets in a more effective way. The planet has biophysical limits on natural resources production and waste absorption. Buildings are one of the main factors in energy consumption and greenhouse gas emissions. Buildings consume about 40% of global energy consumption. All building services such as heating, ventilation, and air conditioning (HVAC) systems consume more than 60% energy in buildings, which is mainly supplied by fossil resources. Today, because of the need for an effective method to achieve efficient energy and biocompatible architecture, the use of natural ventilation systems in buildings has become more significant. One of the methods to create comfortable conditions in the interior is a use of evaporative cooling in the cooling systems. Unlike air conditioners, evaporative cooling can be considered as an acceptable solution for sustainable construction, which reduces energy consumption and greenhouse gases. Evaporative cooling is widely used as a passive cooling method in the built environment. In the system, the movement of air on a wet surface causes the Water evaporation through the air energy absorption, thereby reducing the temperature and increasing the amount of vapor contained in the air. We need indicators to demonstrate the current carrying capacity of the Earth so that decision makers are better informed to set goals, establish options for actions, and monitor progress regarding stated goals. Footprint is a quantitative measurement of natural resources and it is used to assess the extent of human activities impact on global sustainability. Ecological Footprint was initially developed by Wackernagel and Rees in 1992, and is now widely used as an indicator for environmental sustainability. The international average Water Footprint is 7452(〖 Gm〗 ^3⁄ year) and this amount is reported to be 102/65(〖 Gm〗 ^3⁄ year) for Iran. The aim of this study is to design a Passive cooling system to provide comfortable conditions in residential Buildings. Also, with minimal Water and electricity consumption, it will reduce ecological Footprints and Water Footprints and also reduce the amount of electricity consumption in the building. This research was done experimentally-analytically. In order to calculate the efficiency of the proposed system, on August 4th to 7th, the temperature, humidity, and wind speed of the interior room were measured by considering the system. The Hybrid Passive Cooling System (HPCS) consisted of two distinctive systems: the Solar Chimney (SC) and Evaporative Cooling Cavity (ECC). The ECC system was connected to the northern view of the room and SC system was installed to the southern view of the room. The air entered the tower via the openings of the head tower in all directions and passed through the clay cylinders. In this section, the air is cooled and diverted downward. The SC system creates sufficient temperature difference between the interior and exterior by maximizing the solar energy gain and performed air ventilation in the SC and ECC systems. The proposed hybrid system was built in the campus of Azad University, Kermanshah branch in August and was tested from August 4th to 7th. In order to calculate the efficiency of the proposed system, on August 4th to 7th, the temperature, humidity, and wind speed of the interior room were measured by considering the HPCS. To evaluate the Water consumption of the HPCS, two scenarios were considered and their results were compared with each other. Scenario (1): on August 4th-7th, the amount of Water reduction inside the clay cylinders was measured from 9: 00 AM to 3: 00 PM. Scenario (2): On August 18, the room temperature and humidity were measured from 9: 00 AM to 3: 00 PM. Based on the results, Cool performance of HPCS: the lowest temperature was recorded 21. 1 ° C at 9: 00 AM on the 5th of August. The lowest temperature is noon on 22. 9℃ and on the 6th of August. At 3 PM, the lowest air temperature of 23. 72 was reached on the 5th of August. The highest difference between the temperature of the inlet windcatcher and the outside environment is 16. 3℃ , which is on the 7th of August and at 3: 00 PM. the ECC system can increase the RH of air by an average of 34 %. the highest outlet air velocity of the tower is 0. 72 m⁄ s, at 3: 00 PM on the 5th of August. The lowest air velocity is 0. 5 m⁄ s at 9: 00 AM on the 6th of August. Water and electricity consumption of evaporative cooler in scenario 2: To investigate scenario 2, on August 18, the temperature and humidity inside the room and the outside environment were measured from 9: 00 AM to 3: 00 PM. The lowest and highest levels of indoor humidity are 16% at 3 PM and 27% at Noon, respectively, while the outdoor humidity is 13% at 3 PM and 19% at 12 Noon. The evaporative cooler lowers the indoor ambient temperature by an average of 5% and increases the ambient humidity by an average of 7%. Comparison of electricity and Water used in scenarios 1 and 2: The amount of electricity consumed in Scenario 1 is zero, but in Scenario 2, this value is 12112. 9 kJ per day. The environmental Footprint of electricity consumed in Scenario 1 is zero, but in Scenario 2, it is 1. 05 Gigabits per year. The Water used in Scenario 2 is 0. 04 m^3more than Scenario 1. The results showed that the chamber can provide comfort conditions with zero energy consumption by using a hybrid system during the hottest days of the year from 9: 00 AM to 3: 00 PM. The power consumption of the evaporative cooler in the 3 months of summer is 1. 13 GJ, while the power consumption of the designed hybrid system is zero. The ecological Footprint of the power consumption of this system is zero, while the ecological Footprint of the evaporative cooler is 1. 05(Gj⁄ year). From the data obtained, we conclude that the passive hybrid cooling system has the lowest ecological Footprint of Water and electricity compared to evaporative coolers. The system is also able to provide indoor comfort on the hottest days of the year.

Due to the lack of availability of synoptic stations, the high costs of their construction, or the possibility of the inaccuracy of their data or inaccurate calibration, it is better to find alternative tools, which meteorological datasets are one of these suitable devices. In this study, two datasets, GPCC and AgMERRA, were evaluated. The purpose of this study is to investigate the accuracy of these two datasets in calculating the Water Footprint of maize for a specific crop in a specific region as case studies. For comparison of the estimations, the average estimation, R2, RMSE, and maximum error (ME) were used. The results showed that GPCC is more efficient than AgMERRA in estimating the Water Footprint of maize. The average Blue, green, and the total Water Footprint of maize in this province were 242/58, 149/47, and 392/05 m3/ton which was 207/58, 143/78, and 351/35 m3/ton for GPCC and 149/06, 110. 58, and 259/64 m3/ton, respectively. According to the results, both datasets were more efficient in estimating the green Water Footprint than the Blue Water Footprint. This study shows that datasets can be suitable tools in meteorological studies in agriculture, and if they are validated and calibrated, they can be used in various Water management, such as irrigation management, Water resources management, and agriculture management.

Date is one of the most important horticultural products in Iran, which plays an important role in added value of the agriculture, economy and food security. Water resources restriction is one of the main challenges of date product in different areas. Thus, consumption management and optimal use of Water resources for production is essential. A practical approach to Water resources management is estimation of crop Water requirements and determination of Water volume consumed in the process of crop production. Virtual Water is a measure to estimate actual Water use by different crops. Therefore in this research, date Water requirement was firstly estimated by CROPWAT in Sistan and Baluchestan Province. Afterward, the volume of virtual Water, Water Footprint, Blue and Green Water were calculated for growing seasons of 2011-2017. The results showed that the average date Water requirement is 21976. 52 m 3-1 ha in this province. However, the amount of applied Water was measured to be 46659. 58 m 3-1 ha. This indicates a low Water productivity for date production in this province, as the Water productivity of date was calculated to be 0. 29 kg/m 3. The average application of Water for date production was estimated to be 399. 67 million Cubic meters. Iranshahr, Saravan, Sarbaz and Nikshahr had the highest exploitation of Water resources. The average virtual Water for date production was found to be 3. 82 m 3- kg 1. The results of estimated Footprint showed that this province has a low potential for using rainWater to irrigate date palm.

Water scarcity is a prominent feature of arid and semi-arid regions that jeopardize agricultural production. Therefore, efficient management and use of Water resources in agricultural production is essential. One way to manage and increase Water use efficiency (WUE) in agriculture is to determine the amount of Water used in the production process of agricultural crops, which is used to calculate the amount of Water consumed in crop growth stages from the virtual Water index. Therefore, the purpose of this study is to calculate the Water use efficiency (WUE) of agricultural products in the Khash region under the virtual Water and Water Footprint approach. Therefore, the Water requirement was first obtained using the CROPWAT model. Then, the volume of virtual Water, green Water Footprint, and Blue Water were calculated using Data Envelopment Analysis (DEA) to calculate Water use efficiency. The results showed that 20. 15% of the total Water requirement of Khash agricultural crops is provided by green Water and 79. 85% by Water. The virtual Water content of crop production in this region is 853 m3/ton and the Water Footprint shows the total amount of Water harvested for agricultural production is 133. 554 million m3. The DEA results show that the average Water use efficiency of crops in the Khash region is 70. 8%. Corn, potato, onion, tomato, eggplant, melon and Watermelon, alfalfa, forage corn, and sorghum with efficiency score 1 Component of efficient crops and dates, grapes, wheat, rice, and barley were among the inefficient products. Using the Fair Ranking Method (FRM) we found that the least efficiency was related to dates and the highest to sorghum product. Finally, it was found that products with a higher Water Footprint had a lower Water use efficiency.

The Footprint of Water in a product is defined as the used Water to produce it. Present study is conducted with the aim of calculating the Footprint of Water in farm and gardening products in 24 plains of Kermanshah province in the 2015-2016 cultivative year. The function and parameters impressing the calculations were collected using the statistics provided by agricultural organization of Jihad. The aquatic need of plants was extracted by CropWat software and the Footprint of products was calculated. Results showed that among the agricultural studied products, of his plain, Watermelon, forage corn and Sugar beet were identified as the appropriate products according to average index of Water Footprint and on the other side, sesame, beans and sunflower were identified as the the most inappropriate products according to the index. In the gardening sector, almond and cherry-sour cherry were identified as the most inappropriate and appropriate products according to the above index, respectively. Among all the plains of Kermanshah, kermansh allocated the most portion of Water index Footprint in the gardening sector. The Footprint of Blue Water is nearly more than green in studied products; representing the dependence of products to surface and ground Water resources. Hence, according to recent droughs and Water shortage, Water resources must be used accurately and decision must be made for cultivating the products with less Water requirement and better performance Also, the index of Water Footprint in products can be reduced considerably by measures such as deficit irrigation, mulching and by the use of modern irrigation systems.

While agricultural Water Footprint consist more than 90 percent of Iran’, s fresh Water resources, about one third of it is used for animal and chicken husbandary. The aim of this study was to investigate the Water Footprint and Water Footprint in poultry sector using the Mekonnen and Hokkstra method in three provinces of Tehran, Alborz and Qazvin. In this study, the virtual Water Footprint in poultry products, in Tehran, Alborz and Qazvin provinces, was estimated. The values of Water Footprint for producing Chicken was estimated as much as 5. 8, 5. 81 and 6. 08 m3/kg, and it was estimated as much as 4. 26, 4. 66, 4. 22 m3/kg for egg, in Tehran, Alborz and Qazvin provinces, respectively. It is noteworthy that the global average Water Footprints for chicken and egg productions are 4. 3 and 3. 34 m3/kg, respectively. Comparing these values shows that the Water Footprint in poultry production in Iran is higher than the global average. Given the low Water Footprint for chicken and comparing with that of beef, it is recommended to focus on chicken products and for saving Water and food security, simultaneously,the barriers to poultry should be eliminated. Considering the meaningful difference of Water Footprint between the two approaches of natural and industrial poultry husbandary, the last method is suggested.