PROGRESS IN GEOGRAPHY ›› 2017, Vol. 36 ›› Issue (2): 171-181.

• Articles •

### Spatiotemporal patterns and driving forces of water pollutant discharge in the Bohai Rim Region

Kan ZHOU1,2(), Jie FAN1,2, Hanchu LIU1,2

1. 1. Key Laboratory of Regional Sustainable Development Modeling, CAS, Beijing 100101, China
2. Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China
• Online:2017-02-20 Published:2017-02-20
• Supported by:
National Nature Sciences Foundation of China, No.41501139, No.41530634;Science and Technology Service Network Initiative of the Chinese Academy of Sciences, No.KFJ-STS-ZDTP-021

Abstract:

A clear understanding of the spatiotemporal patterns and driving forces of water pollutant discharge has a crucial practical significance for regional joint reduction and prevention of water pollution. Based on the cross-section data of water pollutant discharge and socioeconomic parameters in 67 cities at the prefectural level or above, the spatiotemporal patterns and effects of spatial association of water pollution are quantitatively measured in the Bohai Rim region. Meanwhile, the socioeconomic drivers of water pollutant discharge are estimated by using the econometric model, and some suggestions for the reduction and control of regional water pollution are put forward. The results show that: (1) The Haihe River Basin is the largest and the most prominent watershed with regard to the total quantity and increment of water pollutants in the Bohai Rim Region. Its COD and NH3-N discharges accounted for 38.94% and 39.23% of the regional total discharges, respectively. (2) The spatial pattern of high water pollutant discharge areas has changed greatly, from scattered to continuous distribution since 2005. The Beijing-Tianjin-Hebei region, the Central and Southern Liaoning region, and the Shandong Peninsula region become the superimposed areas of high discharge zone of COD and NH3-N. (3) Discharges of water pollutants have significant spatial association effects in the Bohai Rim region, and the significance of water pollutant discharge presents a general decreasing trend from the coastal area to inland areas. Moreover, the Beijing-Tianjin-Hebei region has been situated in the hotspots for a long period, and the coverage of hotspot and sub-hotspot areas has expanded continuously from the Beijing-Tianjin-Hebei region to the Haihe River and Huaihe River Basin since 2012. (4) By means of an ordinary least squares (OLS) model estimation, it is demonstrated that there are significant differences in the driving forces of water pollutant discharges. Economic growth rate and fixed asset investment show marked positive correlation with COD discharge, and the level of urbanization and industrialization act as a disincentive to COD discharge. Population size is the primary driving factor of NH3-N discharge in the Bohai Rim region, and fixed asset investment and foreign direct investment also show marked positive correlation with NH3-N discharge. There is an appreciable association of high capital investment and high water pollutant discharge in the Bohai Rim region. But high economic development level depresses the discharge of water pollutant, especially in the accumulation zone of high intensity discharge.