The purpose of this study is to design real-time and long-term monitoring water quality buoys, installed at Chin-Wan Bay in Penghu, with Wireless Sensor Network (WSN) communication technique. Results are summarized as follows:
1. The early assessment in-situ survey of 10 buoy mooring points showed values of pH and DO near coast were higher than outside of this bay, but turbidity and salinity were opposite. Diving observation showed most surface bottoms were constructed by soft mud.
2. 2cm Structural deformation of buoy was calculated by the limit-element analysis method and acted with a 3G upward acting force which might make by strong waves during typhoon period.
3. The master buoy was designed to host 3 solar panels to work about 37 hours continuously. In other hand, slave buoys hosted 2 solar panels and worked for 66 hours.
4. Signal transmission distance of XBee-PRO ZNet 2.5 module, the best one from 3 totally tested modules, was at least longer than 1100m in chich the success rate of signal transmission was 92%.
5. A web-based WSN real-time observing and early-warning system was build to integrate the water-quality value transmitted from buoys, the CCD images from an underwater camera and climate data from a small meteorological station. Daily (tidal time), 10-day and monthly isopleth and anomaly graphs of observing data could be analyzed to plot automatically.