expected to be a robust system for evaluation of global tropical ecosystems and not
only peatlands. In general, the SAR irradiates the target area with electromagnetic
waves and analyzes the signals reflected back from the area. The wavelength of
microwaves (one type of electromagnetic waves) is longer than the optical wavelength, and for this reason, the SAR can observe a target area without interference by
clouds and other factors. However, because of the currently low resolution of the
SAR, combination with an optical sensor system is essential. Because the tropical
zone is mostly covered by clouds throughout the year, the integrated MRV system
combined with SAR is the best way to observe the tropics.
The ideal integrated MRV system could consist of microsatellites loaded with
optical sensors and SAR. As a result, it might be possible to continuously observe
A’
A
A
A’
Peatland (>- 6dB)
Backscatter (dB)
Fig. 5.13 Peatland areas suggested by optical sensors (left) and backscatter signal of PALSAR2/
HH(L-band) images along the cross-section A–A
0 (right)
5 Evaluation of Eco-Management of Tropical Peatlands
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