Aspen trees (deciduous forest) comprise more than 90% of the sampled SMAPVEX12 forest sites, with an understory layer of shrubs and grass. The dense shrubs make it difficult to access the sites, therefore the soil moisture and vegetation sampling schemes adopted for these sites are different from the cropland sites. A representative circular area of 200 meter diameter is selected for each forest site and within this area intensive ground measurements of soil moisture and vegetation are made.
Even though my research is not directly associated with forested areas it was great to visit these sites along with other team members and get experience of actual conditions, from which to derive the scientific basis for emission and scattering mechanisms responsible for active and passive signals captured by the PALS airborne instrument (and later SMAP).
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