圖書典藏及影音數位平台

經濟部水利署北區水資源局(以下簡稱本局)所轄石門水庫，在水資源統籌運用上，具備給水、灌溉、發電、防洪、觀光與環境教育等多重功能，水庫營運以來，對台灣北部地區水資源應用均有卓著之貢獻。另寶山第二水庫為一離?水庫，於95年6月完工啟用後，一直肩負供應新竹科學園區所需之用水。而羅東攔河堰將於102年底正式營運，將作為宜蘭縣羅東與冬山等生活圈公共給水水源，以降低對地下水抽用之依賴。 本局轄管水庫、堰體與其集水區的保育及水質一直受到政府及全體國民高度的重視，集水區內活動如農墾、農藥肥料施用、水土保持、水庫上游及社區污水排放、遊樂區興建、畜牧、養殖等都影響到水庫堰體水質及生態保育，為防患集水區過度開發影響水質及自然生態保育已有相關法規管制，環保署及水庫管理單位觀察到水庫有優養化的趨向，為維護水庫水源水質免遭污染，本局積極推動水質監測相關措施，藉由水質監測與水域生態調查資料，建立完善的水庫集水區管理系統，提供相關主管機關擬定集水區管理的目標與污染防治措施及本局於水庫水量操作調度之參考，進而保障民眾飲用水品質及水資源的永續利用。

Water sampling and analysis have been conducted from January to December. Moreover, seasonal ecological and algae survey, 2 times water radiation analysis, annual sediment analysis in reservoirs and the research of environmental monitoring and assessment in 2nd Poshan reservoir during operating have been conducted as well. In this study, there were 20, 6, 2 and 1 water sampling sites in Shimen reservoir, the 2nd Poshan reservoir, Loudong weir and Rongen weir, respectively. The measurements of suspended solids, turbidity, total phosphorus and Chlorophyll-a were generally high and the transparency was low during the fall of water level in Shimen reservoir and 2nd Poshan reservoir in the first half year. Moreover, the measurements of suspended solids, turbidity and total phosphorus were generally high from July to August in Shimen reservoir because of the increase of precipitation in the period of Chan-Hom(昌鴻), Soudelor(蘇迪勒) and Dujuan(杜鵑) typhoon. The measurements of Carlson trophic state index(CTSI) in these two reservoirs were showed as mesotrophic to eutrophic level. The concentrations of organic contaminants of sediment were conformed to the criteria of the sediment quality indicators. The radiation levels, heavy metal content and pesticides contest of the water were safety for human. According to the measurements of water quality index(WQI), Shimen watershed was showed as moderate to excellent grade, and the 2nd Poshan reservoir were showed as good to excellent grade. The domestic wastewater and high concentrations of suspended solids resulted in high concentrations of coli-form and total phosphorus in Loudong weir and Rongen weir. According to the results of water quality analysis in 2nd Poshan reservoir during operating, the water quality were generally conform to the criteria of surface water and drink water source standards. The natural vegetation and the stability of slope around the 2nd Poshan reservoir were well and safety. According to 4 times ecological survey data this year, the differences of fish species in number and composition of the Shimen reservoir and 2nd Poshan reservoir is not significant, and most species are commercial fish. The species composition of benthos and planktonic between the two reservoirs also indicate that there are not remarkable different. Furthermore, to compare the species composition in the aquatic organisms of Shimen watershed and Shang-ping river basin, the numbers in fishes, benthos and aquatic insect species of Shimen watershed is more than Shang-ping river basin, because the stations of Shimen watershed were located in different tributaries. However, the stations of Shang-ping river basin were located in the main river, leading to the differences in habitat diversity and thus affect the biodiversity of the two regions. In addition, Typhoon Soudelor brings strong winds and torrential rains during this summer, cause habitat change. Therefore the population and number of aquatic organisms change since summer investigation. A total of 104 and 85 species belonging to 64 and 56 genera of phytoplankton were recorded at Shimen reservoir and 2nd Poshan reservoir, respectively. The amount of algae cells substantially revealed seasonal changes, higher in spring or summer and lower in winter. The most two dominant groups in Shimen reservoir were diatom and Cyanobacteria, however, Cyanobacteria in 2nd Poshan reservoir. In these two reservoirs, the amount of Chrysophyta is higher than ever before. The algal trophic state index(ATSI) of Shimen reservoir, only Xiandao(仙島) and Amuping(阿姆坪) revealed middle eutrophication in winter, and Ronghua Dam(榮華壩水庫) revealed oligotrophication in summer, the other sites revealed high eutrophication all year, and the most serious in spring. However, in 2nd Poshan reservoir, ATSI of all sites reached eutrophication level all year long, especially in autumn. For microcystins (-LR,-RR,-YR) monitoring results, the total microcystins were below the detection limit. At Shimen watershed, 98 species belonging to 41 genera of microalgae were recorded, and 56 microalgae species belonging to 22 genera were investigated at the races of Baushan second reservoir. The most dominant diatom assemblages were similar between Shimen and Baushan reservoirs. According to the generic index (GI), Sanmin(三民) and Nanjaigo(湳仔溝) in Shimen watershed were polluted over a long period of time, and Luofu(羅浮) revealed serious pollution in autumn. For this reason, these three sites should be managed as key regions of water-monitoring. In addition, only Changhui Bridge(昌惠橋) in the race of 2nd Poshan reservoir were revealed middle pollution of water quality this year again. No matter how, the monitoring project should be proceeded to assess the effects of river works. For Shimen and the 2nd Poshan reservoir water quality and ecological environmental management system, regular survey results of water quality, aquatic and terrestrial ecosystem were uploaded.