Evaluation of Unconventional Water Resources Based on Knowledge Granularity

Abstract

Water resources are important natural resources and play a key role in economic development and social life. China is one of the countries with the most serious water shortage in the world. In the next few decades, the contradiction between supply and demand of water resources will always plague China. Increasing the use of unconventional water resources to mitigate the water crisis is necessary way to achieve a sustainable development. There has been no effective standard yet in China to evaluate the exploitation level and potential of unconventional water resources. This study describes the current status of the exploitation and aims at establishing an evaluation system incorporating the three relevant factors, namely, driving, restrictive, and risk factors respectively, and provides a theoretical basis for the management of unconventional water resources in China. In order to mine the relationship between data and evaluation indexes, the rough set theory is adopted to determine the weight and objectively reflect the importance of each evaluation index. On the basis of the evaluation system, relevant data from 2006 to 2017 in Beijing were selected, and the results show that the urgency of unconventional water resources development in Beijing was generally on the rise with a small fluctuation range.

The Analysis of Present and Future Use of Non-Conventional Water Resources in Heilongjiang Province, China

“…For Equation ( 3), the residents of Heilongjiang are divided into urban and rural populations, and the water use benefit of the total population is calculated according to the water use quota of the two different types of residents [39]; for Equation (4), the "hedonic price method" is invoked to calculate the promotion effect of ecological water replenishment on peripheral consumption [40]; for Equation ( 5), the main types of unconventional water resources in Heilongjiang include reclaimed water, rainwater, and mine water, and the three types of unconventional water sources have different treatment costs. The cost of unconventional water use is the sum of transport costs, management costs, and treatment costs [41]; for Equation ( 6), the sum of water consumption for four types of industries: agriculture, industry, life, and ecology; Equation (7) indicates the total amount of surface water and groundwater that can be allocated to a certain industry [42]; Equation (8) indicates the level of urbanization in each region, i.e., the ratio of the area of built-up area to the total area; Equation (9) indicates the level of urbanization in each region, i.e., the proportion of urban population to the total area and development level of each region, i.e., the proportion of the urban population to the total population; Equation (10) represents the total water purification capacity of all sewage treatment plants in Heilongjiang Province; Equation (11) represents the level of sewage treatment in Heilongjiang Province, i.e., the proportion of the treatment volume to the total volume of sewage discharged [43]; Equation (12) represents the level of construction of the official website for water transport in Heilongjiang Province.…”

“…China has very little freshwater resources-only 10% of the world's total-according to the United Nations Environment Program's Global Environment Outlook (GEO) report. One of the primary barriers to China's overall growth is the scarcity of freshwater, which is essential for socioeconomic advancement [7][8][9]. Nonconventional water resources are increasingly becoming a supplementary water source for urban areas, thanks to advancements in science and technology.…”

Benefit Evaluation of Energy-Saving and Emission Reduction in Construction Industry Based on Rough Set Theory

“…Before assessing the energy-saving and CO 2 outflow decrease potential of waste mud treatment in the construction industry, it is divided according to China's actual situation as a whole and each region. According to international standards, the range of indicators is first determined, but those that have not formed a unified standard are divided according to industry habits or actual development [24,25]. Considering the real situation of Guangdong Province in China, the impact of some indicators such as typhoon on construction needs to be qualitatively analysed.…”

Unconventional Water Use Allocation in Harbin, China

“…This refers to recycled water, rainwater collection, desalinated seawater, brackish water, pit water, etc., which can be used after treatment or can be used directly under certain circumstances. Unconventional water resources can be a better alternative to traditional water resources in the fields of industry, municipal affairs, agricultural irrigation, etc., and they play a significant role in reducing the shortage of water resources in cities and addressing the problem of water pollution [9]. Rainwater, domestic sewage, industrial wastewater, mine pit water, brackish water, etc.…”

“…In order to create a rough set theory based on the determination of the weights of the evaluation, for the evaluation of unconventional water resources to provide a good evaluation index system, driving factors, water conveyance engineering conditions, economic conditions, ecological conditions, etc. [9]; therefore, when assessing the significant factors influencing the utilization of unconventional water resources, indicators such as water resource status, water consumption level, urban development planning, and economic indexes should be taken into account. This is especially true for Chinese cities, where the allocation of water resources is frequently related to local urban development planning and water resources [13,14].…”