[An approach for integrated assessment of eco-risk in coastal waters based on catastrophe theory: taking Luoyuan Bay as a case].

Based on catastrophe theory, this paper established an index system and catastrophe progression model for the integrated assessment of eco-risk in coastal waters, including three risk types of "eutrophication-heavy metal pollution-organic pollution" and three dimensions of "water-sediment-organism". According to the related quality standards, a four-level evaluation standard of eco-risk (zero, low, medium, and high) was proposed, and by using the monitoring data of 2007 and 2009, an integrated assessment of the eco-risk in Luoyuan Bay was conducted. In 2007-2009, the spatial variation of the eco-risk in Luoyuan Bay had a downward trend from bayhead to baymouth, and the risk level in 2009 was overall lower than that in 2007.

[Application of catastrophe progression method in assessing urban ecological security of Xiamen City, China].

Aiming at the potential catastrophic characteristics of coastal city under rapid urbanization, and based on the P-S-R (pressure-state-response) framework and catastrophe progression method (CPM), this paper developed a catastrophe model for the assessment of urban eco-security, and assessed the ecological security status (ESS) of Xiamen City from 1996 to 2006. The results showed that from 1996 to 1998, the ESS had an improving trend, revealing that the rapid urbanization in this period had less effect on the regional eco-security. From 1998 to 2001, owing to the large-scale and profound ecological disturbances from sea reclamation and rapid population increase that far overstepped the ecological remediation ability of Xiamen City's ecosystem itself, the ESS declined rapidly.

[Water pollution load in coastal zone of Xiamen: estimation and forecast].

By the methods of grey prediction and curve regression, the estimation and forecast models of water pollution load in coastal zone of Xiamen City, Southeast China were established, and validated with the statistic data of the pollution load in past decade. The estimation revealed that the industrial wastewater discharge per ten thousand RMB production value decreased yearly, while the total discharge of main pollutants increased gradually. In the total discharge of point source wastewater, about 76% of nitrogen and phosphorus came from domestic wastewater.