The west coast of Taiwan is densely populated with frequently activities for industrial and economic developments. The area is also the site with the existence of Chinese White Dolphin (CWD). Because the arising of ecosystem conservation, the government has attempted to promote the west coast as the marine protected areas (MPAs) for the CWD. Nevertheless, it is required to assess changes of environmental condition and marine environmental quality around the area before the establishment of marine protected areas to the site. If ineffective monitoring is implemented, then the establishment of marine protected areas will be no use. This study was initiated to assess the marine environmental condition by collecting and surveying the long term monitoring data that were published under the government reports and documents to assess the temporal and spatial trends of environmental factors. The data consists of rivers, trench, and marine water or sediments. The study areas covered Taichung County to Yunlin County. The methods for assessing the environmental quality included the use of geographic information system (GIS) for the biological distribution, regression analysis for the trend monitoring of chemical contaminants and physical environmental factors between 2001 ¡V 2010 year surveys. The overall environmental quality within the studied sites were further evaluated for the river pollution index (RPI) and the habitat suitability index (HSI). The survey results of 10 years river monitoring from Taichung to Yunlin showed that Hsin-Huu-Wei River belong to serious pollution with RPI 6.67 value. Yuanlin drainage, one of the six drainages of Chang Hua Coast Industrial Park, belongs to serious pollution with RPI 6.08 value. The RPI results of Six trenches around the Chang-Hua Coast Industrial Park showed that Tien-Wei trench 2, Lun-Wei trench 1, and Ji-An trench belong to mid level of pollution (RPI 3.7~3.975). In the marine water survey, the results showed that the pH values were found lower at southern-ward monitoring station nearby the Formosa Petrochemical Corporation No. 6 Naphtha Cracking Industry site. The nitrogen-NH3 concentrations were found high in Jhuo-Shuei River and No. 6 Naphtha Cracking industry. The concentration of Chlorophyll-a was high in Chang-Hua Coast Industrial Park. In the survey of sediment, Hsin-Huu-Wei River arsenic concentration (As) was over the EPA guidelines, but the concentrations of Cr, Cu, Pb, Zn were within the level of required limits. In the biological survey, the results showed that abundance and species were not evenly distributed with non-comprehensive trends related to the environmental condition or changes. These indicated that biological monitoring survey displayed less important than physical and chemical monitoring for the assessment of man-made pollution or environmental impact from the industrial activities. Overall the monitor sites of river, drainage and trench were differed without a consistent sampling scheme. The offshore sites were sampled greatly in distance, i.e. the farthermost point at four sea miles that had caused difficulties for the comparison of data results collected in different time. It is very uneasy to evaluate the pollution monitoring results. Thus, it is required to develop a long-term environmental quality monitoring plan for the assessment of water quality and sediment of river and marine water with appropriate / consistency sampling method, monitor time and site scheme. Finally, the relevant authorities should implement river remediation to improve the pollution and thereby to maintain the sustainability of marine environment. It is required to establish an integral monitoring program consisting of water and sediment and bio-monitoring in rivers, estuary, and marine to better predict the marine environmental quality. Also the integral and long-term monitoring program should ensure to predict the changes of west coastal and to achieve the effectiveness of marine environment.

The west coast of Taiwan is enriched with biological resources. The areas are the economic development sites with highly industrialized activities and densely population. The government attempts to promote the sites for the establishment of marine protected areas (MPA) because of the existence of Chinese White Dolphin (Sousa Chinensis) which is the most important issues against the sustainable development of economy. Thus, the present study was initiated to assess the marine environmental quality (MEQ) in the west coast of Taiwan. The research consists of the integral monitoring assessments of rivers, estuaries and the marine areas. This work collected, reviewed and analyzed the environmental monitoring data from industrial environmental impact assessment reports and governmental documents for the evaluation of spatial and temporal trends of the west coast areas over the last ten year. The assessment is required to understand the possible interactive problems between the marine protected areas and the marine environmental quality prior to the establishment of MPA acts. The present work consists of the subsection of coastal areas ranging from Hsinchu Country to Taichung Harbour. Ten annual monitoring data including the water quality or sediments of rivers, estuaries, and marine were assessed for the spatial and temporal trends of physical, chemical and biological changes over the years. The approaches for assessing the sites included the geographic information system (GIS) spatial analysis method and linear regression of monitoring data. The levels of pollution were also evaluated by using the river pollution index (RPI). The effect of habitat suitability index (HSI) was also calculated. The results of river water quality assessment showed that the Ke-ya-si, Jhong-gang river, and Nan-gan river were seriously polluted with RPI¡Ö6. The river seiment contaminants (Cu¡BNi) were significantly increased in the Ke-ya-si and Jhong-gang river. The water quality of Taichung Port drainage showed serious pollution with low dissolved oxygen (DO), high concentrations of ammonia nitrogen, and high counts of coli-forms. The Taichung Port drainage sediment contaminants (As¡BCu¡BHg¡BZn) had higher than the average of EPA guidelines. This could be resulting from the significant point source of industries pollutants discharged into the river. The significant amounts of waste water discharged into ocean could cause the impacts to the marine environment. The present study demonstrated the impacts to the river monitoring site although the ocean water quality monitoring contaminants were found without signicant changes in all time. This suggests that the ocean water quality monitoring sites were inconsistently sampled at 4 nm away from the coast which caused the dilution of contaminant concentrations and affecting the monitoring effectiveness. The sediment contaminants in Taichung Port monitoring site showed with the exception of appearing unusual change. The results also showed that there is lack of bio-monitoring program carried out in rivers, estuary, and marine that are imperatively needed to resolve the ineffective sampling protocol implemented in the current coastal environmental monitoring. This is owing to the non unified for authorization between the municipality and environmental bureau. The Canada Ocean Acts on assessing the water and sediment and bio-monitoring in rivers, estuary, and marine as a whole concept were compared with the present study. Finally, the relevant authorities should implement river remediation to improve the pollution and thereby to maintain the sustainability of marine environment. It is needed to establish an integral monitoring program consisting of water and sediment and bio-monitoring in rivers, estuary, and marine to better predict the marine environmental quality. Also the integral and long-term monitoring program should ensure to predict the changes of west coastal and to achieve the effectiveness of marine management.