Optimal Allocation Of Water Resources Under The Background Of Carbon Neutralization

Excess emissions of greenhouse gas are the main cause of global warming.In order to effectively improve the ecological environment,promote the sustainable development of human society and realize the harmonious coexistence between man and nature,it is urgent for all countries to work together to promote carbon peaking and carbon neutrality.The Fifth Plenary Session of the 19th CPC Central Committee formally put forward the concept of"Dual carbon"strategy for green development,and the"Dual carbon"goals have become an important starting point for national ecological construction and regional environmental governance.Carbon emissions are closely related to social economy,industrial structure,agricultural production and ecological construction,all of which are accompanied by a large amount of water resources consumption.Therefore,the optimization of industrial structure and rational allocation of water resources based on the"Dual carbon"goals are of great significance for improving regional water security and promoting sustainable development under the background of climate change.This paper takes the northern Shaanxi Energy Base with drought,water shortage and fragile ecology as the research object,takes the"water-energy-grain"bond as the entry point,comprehensively uses the water footprint and carbon footprint analysis method,and systematically analyzes the characteristics of carbon source and carbon sink activities and the future evolution of supply and demand pattern in northern Shaanxi energy base.Then,constrained by the red line of food and energy production and the goal of carbon neutrality,and in accordance with the principle of regional production factors and industrial chain advantages,this paper carried out the research on the optimization of low-carbon and aquatic industrial structure of the energy base in northern Shaanxi,and put forward the optimal allocation scheme of water resources in the study area.（1）Based on LEAP model,the carbon emission characteristics of the energy base in northern Shaanxi were analyzed from three perspectives:energy supply and consumption,carbon source and carbon sink activities and carbon footprint,and the future global carbon emissions were predicted.The results show that,as a carbon source region,the net carbon emissions in the study area increase year by year,and the activity intensity of carbon source is highly correlated with energy use intensity,which is dominated by industry and transportation,and their energy consumption and carbon emissions account for more than90%and 65%,respectively.The carbon footprint of the study area showed obvious spatial differences,the difference between Shenmu City with the highest carbon footprint and Huanglong County with the lowest carbon footprint was more than 20 times.It is predicted that if the current social and economic development trend is adopted,the future net carbon emissions of the study area will increase to 224 million tons of CO₂equivalent in 2030 and295 million tons of CO₂equivalent in 2060,making it difficult to achieve the goals of"carbon peak"and"carbon neutrality"in the region.（2）Using carbon footprint and water footprint analysis methods,combined with regional energy and food production red lines and related planning,the regional industrial structure was optimized and adjusted based on the carbon neutral goal.The results show that expanding the scale of ecological construction and appropriately reducing the proportion of heavy industry and resource-intensive industries are conducive to regional low-carbon and water-suitable development.On this basis,this paper takes 2020 as the status quo year and predicts the water supply and demand of Northern Shaanxi energy base in 2030 and 2060 at50%water inflow frequency.The results show that the distribution of water resources in the study area is seriously uneven.Surface and groundwater are the main water sources,and other water sources account for less than 2%.The main water consumption sector is industry and agriculture,which accounts for more than 80%of water consumption.In 2030,the water supply and demand of the study area will be 1.798 billion m³and 1.950 billion m³respectively,and the overall water shortage rate will be 7.83%.In 2060,the water supply and demand will reach 1.999 billion m³and 2.067 billion m³,respectively,and the water shortage rate will decrease to 3.27%.However,there was a spatial mismatch between water supply and demand,and the water shortage rate of most districts and counties seriously exceeded the standard.（3）Based on WAS model,the optimal allocation scheme of water resources in the energy base of northern Shaanxi under the Low-carbon and water-appropriate industrial structure is proposed.Using the actual water supply data of the study area in 2020,parameter calibration and validation of the WAS model were conducted.It can be seen that the error rate of WAS was 0.49%,indicating high reliability and accuracy of the simulation results.After the adjustment of industrial structure,the total greenhouse gas emissions from carbon source activities in the study area are expected to decrease from 235 million tons of CO₂equivalent in 2021 to 57 million tons of CO₂equivalent in 2060,and the greenhouse gas absorption from agricultural and forestry systems is expected to increase from 18 million tons of CO₂equivalent to 58 million tons of CO₂equivalent.The study area will achieve"carbon peak"and"carbon neutrality"in 2028 and 2060.After optimal allocation of water resources,only 7 districts and counties in the study area have water shortage problem in2030,and the water shortage rate is all below 10%.In 2060,only Wuqi is in the state of water shortage,and the water shortage is only 310,000 m3,and the water shortage rate is only 0.72%.