Sustainable development is a hot issue in global research today. As a large developing country, China has increasingly prominent conflicts between water use, the population, and the economy, so it is necessary to solve the sustainable development issues represented by water use, the population, and the economy. To explore the evolutionary process for water use, the population, and the economy in China, we calculated the evolutionary path of the center of gravity for water use, the population, and the economy in China from 1965 to 2019 by using the center of gravity model, and we calculated the decomposed contributions of the evolutionary path of the center of gravity for water use, the population, and the economy in China from 1965 to 2019, which the six major areas in China contributed to, by using the center of gravity decomposed contributions model. The results show the following: (1) As a whole, the center of gravity cumulative yearly moving distance for water use was 835.77 km, and the center of gravity moving direction as well as angle were north by east, 18.95°. The center of gravity cumulative yearly moving distance for the population was 113.40 km, and the center of gravity moving direction as well as angle were south by west, 31.50°. The center of gravity cumulative yearly moving distance for the economy was 449.83 km, and the center of gravity moving direction as well as angle were south by east, 8.63°. (2) From the decomposed value contribution rate of the evolutionary path of the center of gravity in the latitude direction for water use, the population, and the economy in China from 1965 to 2019, which the six major areas in China contributed to, Northeast China contributed the most (42.26%, 34.09%, and 39.37%, respectively). The increasing proportion of total water use consumption in Northeast China most positively affected the evolutionary path of the center of gravity for water use in China, moving northwards from 1965 to 2019, and the decreasing proportion of the total population as well as gross regional product in Northeast China most negatively affected the evolutionary path of the center of gravity for the population and economy in China, moving southwards from 1965 to 2019.

To quantitatively reveal the characteristics of the spatial and temporal distribution and the influencing factors of the maize water requirement in Shaanxi Province, the Penman-Monteith model and path analysis were used to systematically analyze the interannual variation and spatial distribution of the maize water requirement at different growth stages in three climatic zones in Shaanxi Province. And the relationship between the water requirement and meteorological factors based on daily meteorological data in Shaanxi Province for the past 60 years. The results showed that the maize water requirement during the whole growth period decreased from 1960 to 1989, with a rate of change of −2.08 mm/a, increased from 1989 to 2019, with a rate of change of 0.38 mm/a, and decreased from 1960 to 2019, with a rate of change of −0.46 mm/a. The water requirement of maize decreases from north to south during the whole reproductive period. That of seedling and male stage are more in the Guanzhong, followed by the north and the least in the south. The water requirement of maize at jointing stage increased from north to south. And the water requirement distribution is more in the north, followed by the south and the least in the Guanzhong area during the maturity period. The average temperature and the duration of the sunshine are the key factors that affect maize water requirement in Shaanxi Province, and have an increasing effect on water requirement, wind speed has an increasing effect on water requirement but is not obvious, water vapor pressure and relative humidity have an inhibiting effect on water requirement. For spring maize, the promoting effect of the duration of the sunshine on maize water requirement was gradually strengthened from north to south. The promoting effect of mean temperature and wind speed decreased gradually. The inhibitory effect of water vapor pressure and relative humidity decreases continuously. This study can provide a scientific basis for the management of irrigation quota in maize growing areas under similar cropping conditions.

As global water scarcity becomes increasingly acute, water demand forecasting has emerged as a critical component in water resource management and planning. This review aims to comprehensively survey and analyze the current state of research, existing issues, and development trends in the field of water demand forecasting. Presently, there are numerous studies on water demand forecasting; however, most of the forecasting results tend to be overestimated. On the mechanistic level, research has gradually shifted from considering single factors to accounting for the complex influences of multiple factors. This paper summarizes the mechanism of water demand from the three levels of agriculture, industry, and residential life. In terms of forecasting methods, various techniques have been explored and applied, particularly new methods based on artificial intelligence and machine learning, which have demonstrated significant advantages in improving forecasting accuracy and handling nonlinear relationships. Despite the notable progress and practical achievements in water demand forecasting, several challenges and issues remain. Future research should focus on diversifying methodologies, comprehensively considering multiple influencing factors, further refining forecasting models and technical systems, strengthening uncertainty and risk management, and emphasizing practical applications and policy guidance.

As China attaches increasing importance to its ecological environment, ecology-related industries have become essential to China’s national economy. However, in the current national economic accounting practice, the ecological industry (eco-industry) is not independent, and the ecological service value ecology creates is currently not within the scope of national economic accounting. To clarify the impact of the development of the eco-industry on the whole regional economy, this paper takes Beijing as the study area. For the first time, the input–output analysis method is adopted to differentiate the eco-industry as an independent sector. Moreover, the ecosystem services value is integrated into the eco-industry, and each coefficient is quantitatively analyzed from an industrial-chain perspective. The results show that the eco-industry exerts a good pulling effect on the regional economy. The inputs and outputs of the eco-industry clearly tend to focus on eco-environmental and public-service-related industries, followed by industries for which ecological development can create value. Judging from the entire regional economy, ecological investment significantly impacts both the education and financial industries. Ecological investment can promote socio-economic development, achieving a 1.318 increase in regional GDP per unit of eco-investment. The results imply that the development of the eco-industry in China should be boosted further and social capital investment should be attracted. Finally, this paper provides a scientific basis for policymakers to better understand the overall situation of both the eco-industry and industry linkages and guide them to develop relevant ecological investment strategies.

What exactly is the contribution of the South-to-North Water Transfer Project (SNWTP)? This is a subject of much debate. There are concerns about the possible effects on the macroeconomy. Most previous studies have tried to answer this question. In order to answer this question quantitatively, it is necessary to separate the effect of SNWTP from many influencing factors. A computable general equilibrium model (SICGE) was built to estimate the economic effect of the South-to-North Water Transfer Project on Beijing. This CGE model was modified by joining the subdivided water substitution module, the total water constraints module, and the water-capital substitution module. Two scenarios were set: one with SNWTP and one without SNWTP. The what-if scenario (without SNWTP) indicates that the water reduction poses a direct threat to economic growth. Employment, capital, and GDP are lower, largely due to water shortages suffered by many industries by comparative analysis with or without SNWTP. The water utilization for the water-intensive industry will decrease the most, and its output will also decrease the most. Without SNWTP, groundwater extraction will increase, which suggests that SNWTP water will tentatively replace groundwater.