Impact assessment of river sand resource shortage under different policy scenarios in China

More than half of the annual global concrete materials were produced in China due to the rapid developing construction industry, which partly led to the shortage of river sand. However, mining rate exceeds the natural replenishment rate of river sand recently, resulting in depletion of natural river sand accumulation. The increasing demand of river sand influences lots of aspects including altered landforms, increasing carbon emissions, ecological deterioration, international trades and disputes. To face the river sand resource shortage in China and to propose possible coping strategies, the data of river sand for construction in China and other related data were collected, and it is suggested that effective policy measures should be taken right now to protect river sand and strictly manage sand mining. Professional solutions for river sand shortage can be summarized as “5Rs” principle, which includes reduce, recycle. reuse, replace and recover. System dynamic model is established to predict the trend of river sand shortage and it was predicted that the gap between river sand supply and demand will come up to 63%. The impact of three policy scenarios is tested in the model, and the gap can be reduced to 35% by single policy scenario, while the scenario with all policy measures is able to reduce the contradiction between supply and demand to 4%. Suggestions are proposed from the aspects of structural and material technology, policy measures and international alliances. Attention should be paid to the shortage of river resources, to realize the sustainable development of the construction industry and other related industries, and to promote the harmonious coexistence of human and nature.