This work presents a novel GA-SA approach to retrieve the constituents of water bodies from remote sensing of ocean color. This approach is validated and compared to the existing algorithms using the same synthetic and in-situ datasets compiled by the International Ocean Color Coordinate Group. Comparing to the other methods, the GA-SA approach provides better retrievals for both the inherent optical properties and various water constituents. This novel approach is successfully applied in processing the images taken by MODerate resolution Imaging Spectroradiometer (MODIS) and generates regional maps of chlorophyll-a concentration, total suspended matter, and the absorption coefficient of color dissolved organic matter at 443nm.

Water quality and unit nonpoint sources (NPS) pollution load from a forest area were studied in a mountainous watershed in Taiwan. The flow rates were measured with rectangular weirs and samples taken for water quality analysis in both non-rainy and rainy days for 2 years. The subroutine of the Hydrological Simulation Program--FORTRAN was used to simulate runoff for additional 3 years. Total annual loads of various water quality parameters were then estimated by a regression model. Most of the parameter concentrations are higher during the rainy days; their values are typically higher as compared to data from other undisturbed forest areas. Nevertheless, the concentration ratio of dissolved inorganic nitrogen to TN or PO4(3-) -P to TP shows TN or TP no correlations with the flow rates, whereas the concentrations of SS and TP are positively correlated with the flow rate. The fluctuation of annual load from this watershed is significant. For example, six major events of the entire year, for which the total duration is merely 6.4 days, contribute 42% of the annual precipitation and at least 40% of the annual NPS loads. The management for controlling the NPS pollution from this forest watershed is discussed.

First flush of stormwater runoff plays an important role in water quality management. Since stormwater runoff during the initial period of precipitation events carries a greater portion of pollution loads, appropriate strategies are needed for effectively controlling the non-point source loads (NPS). In the present study, case studies were performed in two industrial parks for correlating the relationship between pollutant mass and the runoff volume. Three precipitation events were used for calibration and verification of a deterministic model, Storm Water Management Model. The model was then used to simulate all rainfall events in a particular hydrological year to determine the relationship between interceptive amounts of initial runoff and their corresponding reduced portion of annual NPS loads. The results indicate that the first 6-8 mm of a storm runoff depth includes more than 60% NPS loads. If the depth is increased to 10 mm, 80% NPS loading can be contained. The interceptive volume for eliminating 80% NPS loading in Guan-Tian and Yong-Kong industrial areas are 7 and 12 mm, respectively.

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