There are about 15.8 million hectares of mangroves worldwide or merely 0.6% of the earth's surface but 41.4% of the total mangrove cover is in tropical Asia or approximately 6.5 million hectares. Mangroves act as the first line of defense against terrestrial sediments. They serve as breeding grounds for land and marine animals. Currently, mangroves suffer an accelerated decline due to rapid population growth. In order to achieve sustained productivity through multi-use by proper zoning, a comprehensive source on information and knowledge on mangrove conditions are needed. Remotely-sensed data can be a common and steady information resource in Asian Region.mangrove.gif
What are mangroves?"Trees that inhabit muddy shores of tropical regions, where they spread by emitting aerial roots, which fasten in the saline mire and eventually become new stems. The seeds also send down a strong root while yet attached to the parent plant"

The general aim of our research on mangroves is to utilize of remote sensing methods in the mangrove canopy characterization and to create a model of the mangrove forest reflectance. Specific objectives include:

  • Identification of different mangrove canopy characteristic that are measurable from remote sensing systems
  • Development of different remote sensing techniques that can be used to measure mangrove canopy characteristics
  • Application of the canopy reflectance model in the interpretation of satellite imagery
  • Quantification of the relative importance of parameters that govern reflectivity of mangrove canopies
  • Measurement and field survey to supplement model needs
  • Utilization of acquired remotely-sensed data to illustrate applicability and performance of the model

The figures below show the measurement approach and the results (Click to enlarge). Multidirectional reflectance measurements (left) were performed on a mangrove tree using a visible-near infrared spectrometer equipped with a tilt sensor and camera/video. This data is used to simulate the signal coming from a remotely-sensed data (right).

mangrove_band.gif   mangrove_brdf_small.gif

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