Image monitoring for the growth area of Bolboschoenus planiculmis and investigating into its offshore migration at the Gaomei Wetland

• Main Author: 楊承諭
• Other Authors: 張憲國
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/fkeur5

碩士 === 國立交通大學 === 土木工程系所 === 107 === The Gaomei Wetland is one of national important wetlands at the Taichung coast and provides a rich and diverse ecological habitat for marine animals. Bolboschoenus planiculmis, which is listed as one of endangered plants by The Council of Agriculture in Taiwan, is a dominant plant and very important for the maintenance of biodiversity in Gaomei Wetland. Step-measurements spend much time and coast to or survey the growth area of Bolboschoenus planiculmis. Unmanned Aerial Vehicle (UAV) with aerial photography has high efficiency and flexibility to monitor the growth of Bolboschoenus planiculmis. The application of UAV on monitoring the growth of Bolboschoenus planiculmis and investigating into its offshore migration at the Gaomei Wetland is studied in this thesis. The supervised Gaussian maximum likelihood classifier is used to classfy the Bolboschoenus planiculmis from other three kinds objects on each image. The growth areas of Bolboschoenus planiculmis by foot-measurement and by image classification are close during the time of from June to September. The relative error between two results is about 1% to 6%. The correlation coefficient between the variations of temperature and of growth area for the period of growth and senescencefrom 2012 to 2017 are 0.49 and 0.74, indicating moderately and highlycorrelated, respectively. However, the correlation coefficient for the maturation period is 0.08, showing modest correlation between two kinds of variations. The elevation difference at the toe of the Gaomei seawall between 2001 and 2017 shows an increase of about 1.00 m~1.50 m. Due to such beach accetion the seawater-immersed time for Bolboschoenus planiculmis at the toe of the Gaomei seawall is 6.78 hr/day for 2001 and becomes 0 hr/day for 2017. The reduction of seawater-immersed time may be a key factor of offshore migration Bolboschoenus planiculmis at the toe of the Gaomei seawall. The suitable seawater-immersed time for habitat living of Bolboschoenus planiculmis is estimated to be 0.14 hr/dayto 4.61 hr/day.