Suchergebnisse

Making the distinction between drought and water scarcity is not trivial, because they often occur simultaneously. In this study, we used Copulas to quantify the relationship between drought and water scarcity. Beijing&ndash ; Tianjin&ndash ; Hebei Metropolitan Areas (BTHMA) was chosen as the study area. Standard Precipitation and Evapotranspiration Index (SPEI) and water exploitation index plus (WEI+) was chosen to represent metrological drought and water scarcity. Inverse Distance Weighted method was used for spatial analysis of SPEI and WEI+, and Archimedean Copula was used to establish two-dimensional joint probability distribution of SPEI and WEI+. The results are as follows: (1) The southern part of the study area was wetter. The middle part was drier, with moderate drought happened for most times. (2) WEI+ of Beijing and Tianjin showed significant decreasing trends from 2000 to 2015, while WEI+ of Hebei Province did not, which indicated that Hebei Province is facing much severer water scarcity situation than Beijing and Tianjin. (3) Gumbel copula was the best-fitting model to establish the joint probability distribution of SPEI and WEI+. The condition probability provided a probability distribution of water scarcity under different drought conditions, which can provide technical support for government managers during policy making.

Water pollution is a prominent and urgent environmental problem that represents a significant challenge in solving the water resource crisis. The ability to choose an optimal environmental policy can provide support for decision makers to effectively control water pollution. This study presents an agent-based model (ABM) approach involving two classes of agents, agricultural household agents and factory agents, to simulate pollutant discharge, and discusses the effectiveness of the whole system and subsystems under multiple policy scenarios involving a combination of environmental tax (ET) and payments for environmental services (PES). This idea is applied to the Shanmei Reservoir watershed, one of the important reservoirs watersheds in China. The results showed that: (1) the ABM represented well pollutant discharge scenarios where Nash coefficient (NSE) values were greater than 0.76 ; (2) though ET and PES policies were both effective in reducing water pollution, PES was more effective at reducing pollution from households, while ET was more effective at controlling industrial pollution emissions ; (3) considering the environmental costs and general effect of the system, a medium degree of PES for agricultural household agents and a medium degree of ET for factory agents were found to be optimal for controlling water pollution in this watershed. A differential compensation mechanism and the introduction of market incentives were recommended to reduce the financial burden of the government. The results also demonstrated that ABM was helpful for choosing an effective policy to control pollution emissions and realizing environmental objectives and socio-economic co-benefits. The model structure and parameters should be optimized in specific cases because of the uncertainty of partial parameters and the neglect of the consumption process. These findings could be helpful for providing guidelines for water pollution control and sustainable water management in China.

China is a maritime power. However, as its economy develops rapidly, China lacks freshwater resources. The water resources per capita are low in China and are less than a quarter of the global mean value. The development and utilization of desalination, a new unconventional water resource in coastal areas, has gradually attracted the attention of the central and local governments. This paper introduces three aspects of the comprehensive utilization of seawater in China, including the desalination of seawater, the direct use of seawater, and the use of seawater as a chemical resource. Based on the recent status (2017) of comprehensive seawater utilization in China, the prospects for optimizing the utilization of seawater resources are presented. Furthermore, the restrictive factors and potential countermeasures for the increased use of seawater desalination are investigated. Several recommendations are presented, specifically, improving the laws, using regulations and standards related to desalination, strengthening the policies that support enterprises that use desalination, gradually improving the localization rate of key technologies and equipment, and devoting additional attention to the problems associated with brine processing. Seawater is expected to become an important supplemental source of water in coastal areas of China, and the resources needed for its use will be developed as a strategic and influential industry.