*Article* **Research on Water Rights Allocation of Coordinated Development on Water–Ecology–Energy–Food**

**Wenge Zhang, Yifan He \* and Huijuan Yin**

Yellow River Institute of Hydraulic Research, Yellow River Conservancy Commission, Zhengzhou 450003, China; zhangwenge@yeah.net (W.Z.); sabersamav587@sina.com (H.Y.)

**\*** Correspondence: f15036102300@163.com; Tel.: +86-15-036102300

**Abstract:** Water rights trading is an important way to solve the problem of water shortage by market mechanism. The allocation of water rights among ecological water, energy water, and grain planting water are the basis of the regional water rights trade. In this paper, the concept of coordinated development of water–ecology–energy–food is proposed. We build a water rights allocation model with fairness, efficiency, and coordinated development as the goal, to achieve water security for various industries. Taking Yinchuan city as an example, the results showed that compared with the current water rights the water rights of life increased by 1.07%, the water rights of ecology increased by 1.85%, the water rights of energy industry decreased by 1.09%, the water rights of food planting decreased by 3.27%, the water rights of other agriculture increased by 0.83%, and the water rights of the general industry increased by 0.65%. After the allocation of water rights, the cooperativity of water–ecology–energy–food increased by 7.56%, and the total value of water resources in various industries increased by 2.31 <sup>×</sup> <sup>10</sup><sup>8</sup> CNY. A new water rights allocation model is developed in this paper, which can provide a reference for the allocation of water rights among regional industries.

**Keywords:** water rights allocation; coordinated development; water–ecology–energy–food; emergy method; Yinchuan city

#### **1. Introduction**

Water, ecology, energy, and food form the basic conditions of human survival [1], and these four resources are associated with each other [2,3]. The coordination and effective uses of them not only alleviates the resource crisis [4], but also promotes the coordination of the urban social economy [5]. As a basic natural resource, strategic economic resource, and an ecological environment of important control elements [6], water can become the carrier of the coordinated development of effective regulation and the control of various resources. Reasonable water rights allocations between industries can solve the contradiction between supply and demand of regional resources [7]. It is also an important measure to promote local water–ecology–energy–food coordinated development and to effectively promote the ecological protection and high-quality development of the Yellow River Basin.

The middle and upper reaches of the Yellow River Basin Is a typical arid and semi-arid area due to the shortage of water resources and the fragile ecological environment. At the same time, this region is also an important energy production base and food planting base. Water, ecology, energy, and food are important influential factors of the regional social and economic development. The scientific analysis of the coordination among the four resources can play an important role in solving the contradiction between the supply and demand of regional resources and promoting the sustainable development of the regional economy. Many scholars have studied the coordination between regional resources. In the water-ecological-energy-food system, the relationship among waterenergy-food (WEF) has been extensively studied worldwide [8–10]. The study of the WEF system consists mainly of two aspects: firstly, the link between the energy and

**Citation:** Zhang, W.; He, Y.; Yin, H. Research on Water Rights Allocation of Coordinated Development on Water–Ecology–Energy–Food. *Water* **2022**, *14*, 2140. https://doi.org/ 10.3390/w14132140

Academic Editors: Qiting Zuo, Xiangyi Ding, Guotao Cui and Wei Zhang

Received: 21 June 2022 Accepted: 4 July 2022 Published: 5 July 2022

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**Copyright:** © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

water consumption, the food industry relations, and the feedback mechanism [11–13] (for example, such as Wu [14] and Jesus [15] revealed the associated mechanism to establish a link between the WEF model using integrated resource management for an area). Secondly, is the comprehensive safety assessment of the regional water-energy-food system (see Chen [16] and Zhang [17], respectively) on China's Inner Mongolia and China's global water-energy-food comprehensive safety evaluation. The development and utilization of water, food production, and energy production are directly affecting the state of the local ecological environment. It is very urgent to protect the ecological environment. However, few scholars add ecology to WEF for discussion. In this study, the ecological security is added in the water-energy-food system in order to form the water-ecological-energy-food (WEEF) composite system.

In the water–ecology–energy–food system, water, with its unique liquidity and circularity, becomes the link of the WEEF system. Reasonable water rights allocations can effectively relieve the contradiction between the water industries [18,19], and it can be an important means to promote the coordinated development of water–ecology–energy–food in the region. The water rights allocation mode aims at the coordinated development of water, ecology, energy, and food, and is an important measure to solve the increasingly prominent contradiction [20] among ecology–water, energy–water, and food–water. If we take water resources as the carrier and the object of regulation, and rationally allocate the water rights of ecology, energy, and food to make WEEF resources mutually promote development, we can realize mutual benefit and a win-win of multiple resources, and achieve the goal of coordinated development of water, ecology, energy, and food.

In this paper, the coordinated developmental relationship of regional water, ecology, energy, and food is analyzed. We take water as the control carrier and water rights allocation as the means to promote the coordinated development of water, ecology, energy, and food. The water rights allocation model is constructed according to the maximum water efficiency, the most equitable distribution, and the highest collaborative of water– ecology–energy–food. Water rights must be allocated to life, ecology, the energy industry, food planting, other agricultural and the general industrial six water industries. The water rights allocation model of coordinated development on water–ecology–energy–food is put forward in this paper. It will provide reference and basis for the optimal allocation of water rights and water rights trading in the region, and help promote the concept of coordinated development of water–ecology–energy–food.

#### **2. Materials and Methods**

#### *2.1. The Correlation Theory*

## 2.1.1. The Concept and Basic Principles of Water Rights Allocation

Water rights is a type of property rights, which has a different connotation after a long time of formation and development in different countries. In China, water rights are considered to be the ownership and the rights to use water resources [21]. China's water law stipulates that the ownership of water resources belongs to the state, so what is actually allocated is the right to use the water resources. Water rights allocation refers to the distribution process of water resources use of a river basin or a region according to certain rules and mechanisms. A water rights distribution system can solve the scarcity of water resources and improve the efficiency of water resources utilization. It is an effective method to realize the optimal management of water resources.

The principles of water rights allocation generally include fairness, efficiency, basic domestic water security, basic ecological water security, etc. In order to ensure the safety of production water in ecological restoration, key energy industries, and food planting areas, the water rights allocation principle of coordinated development of water-ecologyenergy-food is put forward in this study. This principle is helpful to solve the contradiction between the supply and demand of water resources among regional industries and promote the harmonious development of regional key industries.

### 2.1.2. The Definition of Coordinated Development on Water–Ecology–Energy–Food

Haken [22] believes that "coordinated development" is a process of co-evolution and development in a positive direction through mutual influence, interaction, continuous feedback, control, and adjustment among units. Water, ecology, energy, and food are important basic resources in the development of economy and society, as they interact with each other and are connected with each other. The ultimate goal of the coordinated development of water, ecology, energy, and food is to fully and reasonably develop and utilize various resources, meeting the needs of population growth, urban development, and maintaining economic, social, and ecological environment stability.

Based on this, the coordinated development of water–ecology–energy–food can be understood as: aiming at the rational development and sustainable utilization of water, ecology, energy, and food resources. Through the mutual cooperation and mutual feed linkage between the resource subsystems, the resources promote the development of each other, so as to achieve a mutually beneficial and a win-win situation of multiple resources. The circularity and scarcity, the mobility within and between resources, and the infinity of social demand make water resources an indispensable carrier in the construction of the water–ecology–energy–food composite system. Therefore, water resource is taken as the control object in this paper, to achieve the purpose of the coordinated development of water–ecology–energy–food. This process of mutual promotion and common development among resources can be called the coordinated development of resources. The coordinated development of various resources is of great significance to human survival, social progress, economic development and the sustainable development of maintaining a good ecological environment.

## *2.2. Regional Overview of the Study Area*

Yinchuan, as the capital of Ningxia Hui Autonomous Region, is an important central city in Northwest China, and an important trade town on the ancient Silk Road. By the end of 2020, Yinchuan had a total area of 9025.38 km<sup>2</sup> , and a resident population of 2.29 million. On the water resources situation, the average annual precipitation in Yinchuan is only 210 mm. The Yellow River flows through the center of Yinchuan, bringing a large number of water resources, as nearly 90% of urban water comes from the Yellow River. The per capita available water resource in Yinchuan is 640 m<sup>3</sup> , which is 1/11 of the global per capita. Yinchuan crosses the northwest arid region and the eastern monsoon region, so it has various types of ecological uses. However, the natural ecosystem function of Yinchuan is on the low side, and the ecological environmental capacity is small. Its human activities have a strong influence on the environment, and in some areas cause serious environmental degradation. In terms of energy exploitation and processing, there is a large national coal production base, the "West-to-East Power Transmission" thermal power base and coal chemical industry base in Yinchuan. In terms of food planting, Yinchuan is located in the Yellow River irrigation area, which is an important food planting area. The location, terrain, and water system in Yinchuan are shown in Figure 1.

**Figure 1.** Overview map of the location, terrain, and water system in Yinchuan. **Figure 1.** Overview map of the location, terrain, and water system in Yinchuan.

#### *2.3. Construction of the Water Rights Allocation Model 2.3. Construction of the Water Rights Allocation Model*

To build a water right allocation model, the allocation principle should be established first [21]. A multi-objective water rights allocation model is established by taking the principles of fairness, efficiency, and coordinated development of water–ecology–energy– food as the objective function, and the principle of water security in the industry as the constraint. 2.3.1. The Objective Function of Fairness To build a water right allocation model, the allocation principle should be established first [21]. A multi-objective water rights allocation model is established by taking the principles of fairness, efficiency, and coordinated development of water–ecology–energy– food as the objective function, and the principle of water security in the industry as the constraint.

#### The objective function of fairness is reflected by the satisfaction function of water rights allocation in each industry. The smaller the value, the smaller the difference in sat-2.3.1. The Objective Function of Fairness

isfaction with the allocated water rights among industries; that is, the fairer the water rights allocation between the industries is. The equation is as follows: 2 1 / / max max *H H h h h h W WQ W WQ RF* , (1) The objective function of fairness is reflected by the satisfaction function of water rights allocation in each industry. The smaller the value, the smaller the difference in satisfaction with the allocated water rights among industries; that is, the fairer the water rights allocation between the industries is. The equation is as follows:

1

*h*

$$\text{maxRF} = \max \sum\_{h=1}^{H} \left( \frac{\text{W}\_{h} / \text{W} \text{Q}\_{h} - \sum\_{h=1}^{H} \text{W}\_{h} / \text{W} \text{Q}}{\sum\_{h=1}^{H} \text{W}\_{h} / \text{W} \text{Q}} \right)^{2} \tag{1}$$

*H*

where *RF* is the objective function of fairness; *W<sup>h</sup>* is the allocated water rights of industry *h* (m<sup>3</sup> ); *WQ<sup>h</sup>* is the current water rights of industry *h* (m<sup>3</sup> ); and *WQ* is the sum of current water rights of various industries (m<sup>3</sup> ).

#### 2.3.2. The Objective Function of Efficiency

The objective function of efficiency needs to quantify the water resource benefits of various industries, to make the total benefit of water resources after allocation as high as possible. There are differences in the quantitative methods for the benefits of water resources in different fields, so it is necessary to select appropriate methods to uniformly quantify the benefits of water resources in various industries. The emergy analysis method is chosen to quantify the benefits of water resources in this paper. Emergy is a metric created by the American ecologist Odum [23,24], which uses solar energy as a standard to convert different substances and energy into the solar energy that forms it. The emergy method can convert the water resources benefits of various industries into the same dimension for analysis, making the distribution results more real and reliable.

(1) Water resources benefit life, energy, food planting, other agricultural systems, and the general industry

The water resource benefits of the living, industrial, and agricultural system are reflected in the contribution of water resources as a factor of production in the activities of each system [25]. The water resource benefit of the ecosystem is calculated separately according to the benefit of different ecological water use. By analyzing the energy input and output of the system, the ratio of water resource benefit input to the total input energy of all production factors in each system, it can be multiplied by the total output emergy of the system to obtain the output emergy of water resources. The equation is:

$$EM\_h = \frac{EM\_{Wh}}{EM\_{INh}} \times EM\_{OUTh}.\tag{2}$$

where *EM<sup>h</sup>* is the output water emergy of industry *h* (sej), that is, the objective function of efficiency in h industry, including life (*EML*), energy industry (*EMN*), food planting (*EMF*), other agriculture (*EMO*), general industry (*EM<sup>I</sup>* ); *EMWh* is the input water emergy of industry *h* (sej); *EMINh* is the total input emergy of industry *h* (sej); *EMOUTh* is the total output emergy of industry *h* (sej).

#### (2) The water resources benefit for ecology

In this paper, urban ecological water use is divided into three parts: artificial lake replenishment, urban road sprinkling, and green space irrigation. Artificial lake replenishment can produce dilution and purification benefit. Watering urban roads can produce cooling and humidifying benefit and dust removal benefit. Irrigation of urban green space is a necessary condition for the growth and development of green plants, which will bring benefits of carbon fixation and oxygen release. The equation is:

$$\begin{aligned} EM\_{\rm E} &= W\_{\rm Ea} \times \tau\_{\rm DB} + W\_{\rm Eb} \times L \times \tau\_{\rm E} + W\_{\rm Eb} \times \Delta PM\_{\rm I0} \times \tau\_{\rm D} \times 48.62\%\\ &+ (B\_{\rm C} \times \tau\_{\rm C} + B\_{\rm O} \times \tau\_{\rm O}) \times \frac{W\_{\rm Ec}}{W\_{\rm Ec} + W\_{\rm P}}\end{aligned} \tag{3}$$

where *EM<sup>E</sup>* is water emergy of ecology system (sej), that is, the objective function of efficiency in ecology; *WEa* is the quantity of artificial lake replenishment in ecological water (m<sup>3</sup> ); *τ<sup>S</sup>* is the transformity of surface water (sej/m<sup>3</sup> ); *WEb* is the quantity of urban road sprinkling in ecological water (m<sup>3</sup> ); *L* is the latent heat of evaporation (J/g), *L* = 2507.4−2.39 *T*, *T* is the average annual temperature in the study area (◦C); *τ<sup>E</sup>* is the transformity of evaporation (sej/J); ∆*PM*<sup>10</sup> is the variable quantity of *PM*<sup>10</sup> before and after sprinkling (µg/m<sup>3</sup> ); *τ<sup>D</sup>* is the transformity of dust (sej/µg); 48.62% is the control efficiency of sprinkling on dust particles [26]; *B<sup>C</sup>* is the amount of carbon fixation (g); *B<sup>O</sup>* is the amount of oxygen release (g); *τ<sup>C</sup>* and *τ<sup>O</sup>* are the transformities of carbon fixation and oxygen release (sej/g) [25]; *WEc* is the quantity of green space irrigation (m<sup>3</sup> ); *W<sup>P</sup>* is natural precipitation (m<sup>3</sup> ).

(3) The efficiency objective function of water rights allocation established according to the above items is:

$$\text{maxRS} = \max(EM\_L + EM\_E + EM\_N + EM\_F + EM\_O + EM\_I), \tag{4}$$

where *RS* is the objective function of efficiency.
