Establishment of a three dimensional, real-time marine environment monitoring system, DataBuoy™ I, in the Hoi Ha Wan Marine Park, Hong Kong, with connection to the internet

DataBuoy^TM I, a three dimensional, real-time marine environment monitoring system with connection to the internet, has been developed by the Department of Electronic Engineering, City University of Hong Kong (CityU). This equipment can multiplex up to five sensors placed at different depths in the water column for monitoring of temperature, salinity and light intensity. It was installed on a site in the Hoi Ha Wan Marine Park between June and July 2006. Data collected was transferred to the CityU Marine Laboratory at the Hoi Ha Wan Marine Life Centre. Preliminary results showed that Hoi Ha Wan has had a wide salinity variation (9 ppt to 33 ppt) among sites and within two days. During that data collecting period, the water temperature recorded at 30 cm from sea surface reached a maximum of 33.5degC, while that at 7 m deep was 25.5degC. The DataBuoy^TM, therefore, could detect the hypoxia in shallow water caused by low salinity at the water surface whereas the deeper sensors could detect the thermocline associated with the hypoxia in deeper water, if any. Future work involves the setting up of a DataBuoy^TM II network to monitor three areas in Hoi Ha Wan. The data could be collected every few seconds and consolidated in a computer server located in the CityU Marine Laboratory. It would be formatted for display at the Marine Life Centre for visitors \´ information on a mimic panel and on the CityU"s WWW site. This would allow world wide access to the information, making it available on line to the Government Authority, schools and the general public for information and research purposes.