Biomass growth from multi-temporal TanDEM-X interferometric synthetic aperture radar observations of a boreal forest site
Journal article, 2018

Forest growth estimation is important in forest research and forest management, but complex to analyze in diverse forest stands. Twelve summertime TanDEM-X acquisitions from the boreal test site, Krycklan, in Sweden, with a known digital terrain model, DTM, have been used to study phase height and aboveground biomass change over 3.2 years based on the Interferometric Water Cloud Model, IWCM. The maximum phase height rate was determined to 0.29 m/yr, while the mean phase height rate was 0.16 m/yr. The corresponding maximum growth rate of the aboveground dry biomass, AGB, was 4.0 Mg/ha/yr with a mean rate of 1.9 Mg/ha/yr for 27 stands, varying from 23 to 183 Mg/ha. The highest relative AGB growth was found for young stands and high growth rates up to an age of 150 years. Growth rate differences relative a simplified model assuming AGB to be proportional to the phase height were studied, and the possibility to avoid a DTM was discussed. Effects of tree species, thinning, and clear cutting were evaluated. Verifications using in situ data from 2008 and a different in situ dataset combined with airborne laser scanning data from 2015 have been discussed. It was concluded that the use of multi-temporal TanDEM-X interferometric synthetic aperture radar observations with AGB estimates of each individual observation can be an important method to derive growth rates in boreal forests.

Change

TanDEM-X

Growth

Biomass

Interferometric Water Cloud Model

Author

Jan Askne

Chalmers, Space, Earth and Environment, Microwave and Optical Remote Sensing

H. Persson

Swedish University of Agricultural Sciences (SLU)

Lars Ulander

Chalmers, Space, Earth and Environment, Microwave and Optical Remote Sensing

Remote Sensing

20724292 (eISSN)

Vol. 10 4 603

Subject Categories

Ecology

Forest Science

Physical Geography

DOI

10.3390/rs10040603

More information

Latest update

5/23/2018