Quantifying and predicting the Water-Energy-Food-Economy-Society-Environment Nexus based on Bayesian networks - A case study of China

Abstract

The main objective of sustainable development is to ensure the current and future demand can be satisfied. Food, energy and water is the primary human demand. However, China is facing security issues of water, energy and food due to several economic, social and environmental impacts such as economic progress, population growth and environmental change. For this reason, it is important to evaluate the relationship between food, energy and water with sustainability aspects. Using Bayesian network models, we propose a quantitative analysis framework based on the Water-Energy-Food-Economy-Society-Environment Nexus. Under this framework, the causality relations between water, energy, food and economy, society, environment were studied and quantified. Additionally, the demand for water, energy, food was predicted from a perspective of systematic interaction. Different from previous studies, our research is more comprehensive, involving six subsystems. More importantly, we do research from a systematic point of view. Thirdly, the causality in the nexus was quantified. As a result, we found that water withdrawal is directly affected by population growth and energy demand, indirectly by other nodes in the nexus; energy demand is directly affected by GDP and population growth in the nexus; population growth is the only direct cause of changes in food demand. Projections show that the demand for water, energy and food in China will remain at [600,620) billion cubic meters, a growth rate of [4%, 8%) and [0%, 5%) with an average probability of 0.6772, 0.6128 and 0.7055 respectively from 2020 to 2030.