Abstract:In this study, fuzzy synthetic evaluation was used to build a reef ecosystem-health assessment model. To eliminate the dimension effect of sub-indexes, normalization processing was used. Analytic hierarchy process was used to assign a threshold of ecological indicator. The synthetic health index was used to assess the health status of artificial reef areas and contrast areas. Sub-indexes of artificial reef ecosystem health assessments included physical, chemical, and biological factors. Assessment standards were based on seawater quality standards, marine sediment quality, and guidance for the assessment of coastal marine ecosystem health. Data and survey results of a background investigation in July 2013, and a tracing investigation in June 2014 and May 2015, were processed using the ecosystem-health synthetic assessment model. The results indicated that both reef area and contrast area are in a healthy state. The health state of the contrast area was better than that of the reef area in July 2013 before reef construction. Data from June 2014 was consistent with that from the background investigation; the health status of the contrast area was also better, which is related to the disturbance of reef construction and the evolution of the reef system. In May 2015, the health index of the contrast area declined, but that of the reef area increased to 0.838, indicating that the reef is very healthy. Health evaluation indicates that the health of the reef ecosystem in the Beidaihe demonstration area is gradually improving. According to the results obtained with the ecosystem health synthetic assessment model, the state of the reef improved with completion of construction and ecosystem stability; therefore, ecosystem health synthetic assessment is an important method for the management and development of reefs. Researching reef ecosystem health and scientifically assessing artificial reef ecological effects are significant for the construction of reef projects, environment protection, stock enhancement, efficient administration, and sustainable development of fisheries.
