隨著人口和經濟的增長，對水的需求量與日劇增。水庫為飲用水的主要來源，因此如何有效的監測水庫水質是非常重要的。傳統的水質監測方法是利用水庫所設的水質採樣點進行現地的水質採樣，透過採樣所得到的水樣本需送回實驗室進行各水質的化驗，利用化驗所取得的各水質參數值的高低來評估水質的好壞。但由於現地採樣的水質採樣點位稀少，加上點位的分佈稀疏，並不足以表示水庫空間上的水質變化。本研究配合現地的水質採樣時間，以水質採樣前後20天作為選擇條件，從2005年至2013年的福衛二號衛星影像中，篩選出總計28張的衛星影像進行水質迴歸及計算。在水質迴歸的部分，本研究以時空地理加權迴歸模式來推估曾文水庫的濁度及葉綠素值。
時空地理加權迴歸考慮空間及時間的異質性，進行局部性的水質推估，其可產生各時期各測站專屬的係數值，再利用反距離權重法將各時期各測站的係數值推估到整張影像。利用所取得的整張影像的係數值，加上衛星的DN值經計算後所得到的遙測反射率，便能取得各時期的水質分佈圖。利用線性迴歸及地理加權迴歸的成果與時空地理加權迴歸的成果作比較，並以均方根誤差（RMSE）來分析模型之好壞，從RMSE的成果證明時空地理加權回歸在水質推估上的可行性。利用取得的多時期水質分佈圖，輔以雨量及水位資料，進行水質時空變化的分析及探討，並利用超標累加法及經驗正交函數(EOF)找出超標次數最多及水質參數值變化較大的區域，以利於曾文水庫水質的監測及管理。

The population and economic growth has led to the recently increasing demand for water. Water reservoirs are the primary source of drinking water, such that, monitoring reservoir water quality is important. The traditional water quality monitoring approach collects data at sampling points, and then, transports water samples to the laboratory for water quality analysis. However, the traditional method is not representative of the entire reservoir water quality because only a few locations are sampled. Therefore, this study combines Formosat-2 satellite images and geographically and temporal weighted regression (GTWR) to calculate and to map the turbidity and Chlorophyll-a water contents in the Tsengwen reservoir. This water quality map is used to monitor and to analyze the water quality of the entire reservoir. The GTWR is a spatial and temporal regression that considers spatial and time correlation; it runs a regression for each location and time, instead of a sole regression for the entire study area. This study compares the GTWR and the linear regression and GWR model results. Root Mean Square Error is utilized to analyze and to contrast water quality index with different models. Results show that the performance of GWR model is more precise than linear regression, and this algorithm proved suitable for use on water quality monitoring. This study applied accumulate method and empirical orthogonal functions to analyze space-time water quality data and used water quality information to investigate water quality changes.

Chang, C.-H., Liu, C.-C., Wen, C.-G, Cheng, I,-F., Tam, C.-K., & Huang, C.-S. (2009). Monitoring reservoir water quality with Formosat-2 high spatiotemporal imagery. Journal of Environmental Monitoring.
Chu, H. J. (2014). Spatiotemporal analysis of vegetation index after typhoons in the mountainous watershed. International Journal of Applied Earth Observation and Geoinformation, 28, 20-27.
Chu, H.J., Huang, B., & in, C.Y. (2015). The spatio-temporal heterogeneity in the PM10-PM2.5 relationship. Atmospheric Environment, 102, 176-182.
Dekker, A., Malthus, T., & Hoogenboom, H. (1995). The Remote Sensing of Inland water quality. Advances in environmental remote sensing, 123.
Dekker, A. G., Vos, R. J., & Peters, S. W. M. (2001). Comparison of remote sensing data, model results and in situ data for total suspended matter (TSM) in the southern Frisian lakes. Sci. Total Environ., 268, 197-214.
de Moraes Novo, E.M.L., de Farias Barbosa, C.C.,de Freitas, R. M., Shimabukuro, Y. E., Melack, J.M., & Pereira, W. F. (2006). Seasonal changes in chlorophyll distributions in Amazon floodplain lakes derived from MODIS images. Limnology, 7, 153-161.
Duan, H., Zhang, Y., Zhang, B., Song, K., & Wang, Z. (2007). Assessment of chlorophyll-a concentration and trophic state for Lake Chagan using Landsat TM and field spectral data. Environmental monitoring and assessment, 129, 295-308.
Giardino, C., Brando, V. E., Dekker, A. G., Strombeck, N., & Candiani, G. (2007). Assessment of water quality in Lake Garda (Italy) using Hyperion. Remote Sensing of Environment, 109, 183-195.
Kallio, K., Kutser, T., Hannonen, T., Koponen, S., Pulliainen, J., Vepsalainen, J., & Pyhalahti, T. (2001). Retrieval of water quality from airborne imaging spectrometry of various lake types in different seasons. Sci. Total Environ., 268, 59-77.
Liu, C. C., Chang, C. H., Wen C. G., Huang, C. H., Hung, J. J., & Liu, J. T. (2009a). Using satellite observations of ocean color to categorize the dispersal patterns of river-borne substances in the Gaoping (Kaoping) River, Shelf and Canyon system. J. Mar. Syst., 76, 496-510.
Mobley, C. (1994). Light and water: Radiative transfer in natural waters. Academic Press, New York
Nielsen, A. A., Conradsen, K., & ndersen, O.B. (2002). A change oriented extension of EOF analysis applied to the 1996–1997 AVHRR sea surface temperature data. Physics and Chemistry Earth, 27, 1379-1386.
Ostlund, C., Flink, P., Strombeck, N., Pierson, D., & Lindell, T. (2001). Mapping of the water quality of Lake Erken, Sweden, from imaging spectrometry and Landsat Thematic Mapper. The Science of the Total Environment, 268, 139-154.
Pan, J., Yan, X. H., Zheng, Q. A., Liu. W. T., & lemas, V. V. (2003). Interpretation of scatterometer ocean surface wind vector EOFs over the Northwestern Pacific. Remote Sensing of Environment, 84, 53-68.
Tsai, G. J., Chu, H. J., Huang, M. L., Chang, C.H., & Kong S.J. (2015). Applying Feed-Forward and Cascade-Forwards ANNs to estimate reservoir water quality from satellite images. International Symposium on Remote Sensing.
Wang, Y., Xia, H., Fu, J., & Sheng, G (2004). Water quality change in reservoirs of Shenzhen, China: detection using LANDSAT/TM data. Sci. Total Environ., 328, 195-206.
Wang, Z. G., Hong, J. M., & Du, G. S. (2008). Use of satellite imagery to assess the trophic state of Miyun Reservoir, Beijing, China. Environmental Pollution, 155, 13-19.
行政院環保署. (2016). 全國環境水質監測資訊網. From http://wq.epa.gov.tw
李宜真. (2006). 應用福爾摩沙二號衛星影像於水庫水質監測之研究.逢甲大學: 環境資訊科技研究所, 碩士論文.
林孟勳. (2005). 使用高解析力衛星影像量測河海泥砂量值研究. 國立成功大學: 地球科學研究所, 碩士論文.
高振傑. (2008). 應用經驗正交函數分析海岸地形變化特性之研究. 國立交通大學: 土木工程研究所, 碩士論文.
國家太空中心.(2016).From http://www.nspo.org.tw
張智華. (2008). 非點源污染負荷模式及水質生光模式之結合與應用. 國立成功大學:環境工程學系, 博士論文.
張騏顯. (2008). 應用類神經網路與衛星影像於水庫水質推估—以石門水庫為例.中興大學: 木工程學系所, 碩士論文.
陳章瑞, &宋維真. (2011).以地理加權迴歸模式探討都市公園之寧適效益. TGIS.
曾文水庫生態知識環境教育平台. (2016). From http://210.69.129.209/
黃建洲. (2007). 應用Landsat 7 衛星影像與水庫水質監測值研究. 中華大學： 土木與工程資訊研究所, 碩士論文.
黃清勇, &羅璋盛. (2004). 颱風路徑預報誤差EOF分析. 大氣科學, 34，277-290.
黃慶祥. (2006). 水庫水質與光學性質模式之建立及其應用. 國立成功大學: 環境工程學系, 碩士論文.
楊明德, 林佑昌, 蔡婷鈺, &楊曄芬. (2008). 結合衛星影像與模糊理論於水庫水質優養判釋與管理. 中國土木水利工程學刊, 20(2), 205-215.
經濟部. (2011). 曾文南化烏山頭水庫治理及穩定南部地區供水計畫.
經濟部水利署. (2016). From http://www.wra.gov.tw
經濟部水利署南區水資源局.(2014). 應用衛星影像即時監測與水庫水質管理之研究—以曾文水庫為例期末報告書 (1/2).
雷祖強, &鄭克聲. (2000). 應用衛星遙測及隨機變域模擬於水庫優養評估, 農業工程學報, 第46卷第4 期.
劉正千, 張智華, 許華宇, 譚子健, &溫清光. (2007). 應用ISIS高頻譜光學遙測影像與曾文水庫之水質監測. 科儀新知, 29, 29-42.
鄭依凡. (2010). 運用福爾摩沙二號衛星高時空分辨率遙測影像探討曾文水庫水質之時空變化. 國立成功大學, 衛星資訊暨地球環境研究所, 碩士論文.
蕭玲鳳. (2002). 雙颱風路徑分析及數值模擬. 私立中國文化大學: 地學研究所, 博士論文.
蕭國鑫, 吳啟南, &廖子毅(2005). 地面光譜資料與 SPOT 影像應用於水質定量推估研究. Journal of Photogrammetry and Remote Sensing, 10, 169-182.
譚子健. (2007). 應用生光模式及福衛二號遙測影像研究曾文水庫水質之時空分析. 國立成功大學: 環境工程學系, 碩士論文.
嚴偉新. (2007). 東亞地區降水年際變化之研究. 國立中央大學: 大氣物理研究所, 碩士論文.