Measurement of seagrass standing crop using satellite and digital airborne remote sensing

Abstract

The standing clop of seagrass IS hlghly sensitive to environmental disturbance We evaluate 3 optical remote sensing methods for measuring standing crop In the tropical Western Atlant~c Extensive f ~e l d measurements of standing crop were used to define empirical relationships ivith imagery from satellite sensors [Landsat Thematic Mapper and SPOT (Systeme Probatoire d e I Observation d e la Terre) XS (multlspectral)] and the dlgital alrborne lmager CASI (Compact Airborne Spectrographlc Image]) Predictions of standing crop from processed imagery had high coefficients of determinatlon 0 74, 0 79 and 0 81 respectively Using a bootstrap method to measule standard error, the 95 % confidence interval of predictions was found to have a sllnilar order of magnitude to quadrat sampling In sltu at a precision (standard e~ror/mean) of 10% Expllc~t cost-benefit and monltorlng conslderations are discussed