Presenting the optimal model of water resource management based on the virtual water trade perspective

Master thesis

in the field of civil engineering, water engineering trend

The water that is used in various stages of production of any product is called virtual water [1] stored in the product. Many countries located in arid and semi-arid regions, by importing food, preserve part of the water that is needed for domestic production of products for use in other purposes.

In this thesis, after determining various scenarios and examining them comprehensively, the conclusion was finally reached that in planning water resources, while being relatively self-sufficient in agricultural production, water products such as grains should be imported from other countries, including Thailand. did Because this country has features such as short distance, access by sea, suitable political relationship, lower water supply costs and abundant water resources. Also, in order to be present in global markets while discovering the needs of neighboring countries, for example, the UAE and the country's need for products such as potatoes and milk, these products can be exported with appropriate planning to meet domestic needs. With this procedure, in addition to reducing the pressure on domestic water resources, new job opportunities can also be provided by reducing the final price of products that Iran has a relative advantage in producing. Reducing pressure on underground water tables, increasing irrigation efficiency and growing crops according to the climate of each region are among the positive environmental effects of this plan. Keywords: virtual water trade, water resources management, water economy, food security Chapter one: Introduction of virtual water and virtual water trade

1-1: Introduction

The production of many goods requires water. The water used in various stages of product production is called "virtual water[1] stored in the product"; For example, 1 to 2 cubic meters of water is needed to produce one kilogram of dry-grown grain in favorable weather conditions, and 3 to 5 cubic meters of water is used to produce the same amount of grain in unfavorable weather conditions with high temperature and evaporation and transpiration [1]. To produce livestock products, compared to agricultural products, many times more water consumption is needed; For example, to produce 1 kg of cheese, 5-5.5 cubic meters of water are needed and to produce 1 kg of beef, approximately 16 cubic meters of water are needed [2]. In addition to agricultural products, in recent years, few studies have been conducted in the field of water consumption for the production of industrial products; For example, the research result of Williams et al. (2002) shows that 32 cubic meters of water is consumed to produce a 32 MB electronic chip weighing 2 grams [3].

About 74% of the available water resources in the world are used in the agricultural sector [4]. This number for Iran is about 93%. In addition to issues such as climate and technology in the production of products, the nutritional culture of the people also has a great impact on the amount of water consumption of a country; For example, if all humans eat the same diet as people in the West, 75% more water will be needed in the world to produce the required food [2]. Changing people's diet can increase available water resources. Raising this debate and the debates that will be raised in the future sections show that the concept of virtual water makes water more prominent as a fundamental and global issue and expands its management at the micro and macro levels of society and the business field.

In the table below, virtual water has several products and several different diets.

(Tables are available in the main file)

Global trade in goods creates an international circulation of virtual water, which is called "virtual water trade" [1]. Simultaneously with the beginning of the international trade of goods, the circulation of virtual water is moving from one region to another in the world. The word virtual water for the first time with the help of G. E. Allen proposed in 1993 [5]. With more attention of scientists and researchers to the concept of virtual water, quantitative calculations started in this field. Calculations report a massive flow of water being moved virtually by trade in water-borne commodities.

In general, it took nearly ten years since Allen raised the issue of virtual water and until the scientific community paid attention to it [6]. The first international meeting on this topic was held in Delft, Holland, in December 2002. A special meeting was dedicated to the issue of virtual water at the third World Water Summit in Japan in March 2003. According to Hong and Hoekstra [3], virtual water is an essential tool in calculating the actual water used in each country, which is equivalent to the total domestic water used plus the imported virtual water, minus the exported virtual water of a country. This definition is called "basic drinking water" [4] [6]. The basic water consumption of each country is a useful indicator for water demand and is equivalent to the total virtual water enclosed in products, goods and services. 1-2: Virtual water trade: capacities and considerations Research conducted with the help of Hong and Hoekstra (2002) shows that in the years 1995 to 1999, the average annual amount of virtual water being moved, with the help of agricultural products trade It was 695 billion cubic meters [1]. The total water used to produce these products in producing countries was 5400 billion cubic meters. This means that 13% of the total water consumed for the production of products has entered the trade market [1]. Another research with the help of Chapagin and Hoekstra [5] shows that the volume of virtual water being moved with the help of livestock and livestock products trade for the period from 1995 to 1999 was 245 billion cubic meters [7]. If we add the trade of agricultural goods to this number, the volume of virtual water being moved with the help of trade in these years reaches 940 billion cubic meters. Considering the trade of livestock and its products, it can be said that a total of 20% of the water used for the production of agricultural and livestock products has participated in the virtual transfer of water between countries [7].

The term virtual water connects water, food and business. These figures are also a good proof of this matter on a global scale. Countries located in arid and semi-arid regions can conserve the water needed for their production by importing water-intensive goods, such as food, for use in other sectors. It seems almost impossible to transport real water in large volumes and over long distances due to its transportation problems and high costs. Meanwhile, food trade can be a homogenizer of heterogeneous distribution of water resources by virtual transfer of a huge amount of water.

The agricultural sector, as the most consuming sector, consumes about 74% of the world's fresh water resources [4]. Some water-scarce countries, ignoring natural capacities, over-pump groundwater and desalinate sea water to provide part of this water. The results show that producing products in such a situation is more than five times more expensive [8]. Water-scarce countries can, by involving virtual water trade in water policies, not only increase their access to global water resources, but also reduce the pressure on their limited resources. The import of food in order to use the source of virtual water trade affects the economic, social and environmental sectors of each country and has a direct correlation with the country's food security and culture. Water-scarce countries can find an optimal point for the amount of food imports into the country according to their internal conditions, capacities and needs, as well as food security considerations.

Every year, a canal full of water is needed, one meter deep, one kilometer wide, and seven million kilometers long, that is, 180 times the circumference of the earth, to produce 3000 calories of energy daily for 1.6 billion people on the earth[4]. In smaller figures, it can be said that one liter of water is needed to produce each calorie [2]. While the earth will face an increase in population by 2-3 billion people by 2050 [4]. The provision of water and food for this population is already a matter of discussion. Undoubtedly, the challenges facing water resources management are very different from 25 years ago, and the situation will be very different in the next 25 years [4]. The heterogeneous distribution of water resources, the efforts of countries to ensure the food security of their nations, the need to develop water infrastructure and the lack of financial resources in this field, have turned the issue of water for food production into an international issue.