Stem volume retrieval in boreal forests from ERS-1/2 interferometry

C-band repeat-pass interferometry, in particular, the coherence, has been shown to be of great potential for stem volume retrieval. For boreal forests, we have investigated a stem volume retrieval method based on inversion of ERS-1/2 coherence measurements by means of a semiempirical model. A multitemporal combination of several stem volume estimates has been used in order to reduce errors in the estimation. The retrieval procedure was first applied in a forest estate located in Kattbole, Sweden, where accurate in situ measurements were taken. Stem volume was determined both at the stand level (between 2 and 14 ha) and at the pixel level (25 � 25 m). A multitemporal combination of coherence data acquired in stable winter-type conditions gave the most accurate results. Based on the results obtained in Kattbole, the retrieval procedure was extended to a large area of 4235 km 2 around Kattbole. Retrieval was performed in all forested areas on a pixel basis (25 � 25 m), generating stem volume maps. In Kattbole, at the stand level, stem volume up to 350 m 3 /ha was estimated with an error comparable to the ground truth, i.e. 10 m 3 /ha. At the pixel level, the error reached the value of 55 and 71 m 3 /ha in the forest estate and in the large area, respectively. Compared to the results from the stand analysis, the higher error is believed to be mainly due to the higher uncertainty of coherence estimation at high stem volume and to geometric mismatch between field data and coherence data. Moreover, over large areas, spatial variation of the parameters in the model should be considered. D 2002 Elsevier Science Inc. All rights reserved.

[1]  Jan Askne,et al.  Understanding ERS InSAR coherence of boreal forests , 1999, IEEE 1999 International Geoscience and Remote Sensing Symposium. IGARSS'99 (Cat. No.99CH36293).

[2]  Juha Hyyppä,et al.  Backscattering properties of boreal forests at the C- and X-bands , 1994, IEEE Trans. Geosci. Remote. Sens..

[3]  U. Wegmuller,et al.  Influence of biophysical, meteorological and topographic factors on multidate ERS tandem data acquired over forested terrain , 1998, IGARSS '98. Sensing and Managing the Environment. 1998 IEEE International Geoscience and Remote Sensing. Symposium Proceedings. (Cat. No.98CH36174).

[4]  Urs Wegmüller,et al.  ERS INSAR data for remote sensing hilly forested areas , 2000 .

[5]  Lars M. H. Ulander,et al.  C-band repeat-pass interferometric SAR observations of the forest , 1997, IEEE Trans. Geosci. Remote. Sens..

[6]  M. Engdahl,et al.  Verification of the capability of repeat-pass SAR interferometry to provide tree height information in boreal forest zone , 2000, IGARSS 2000. IEEE 2000 International Geoscience and Remote Sensing Symposium. Taking the Pulse of the Planet: The Role of Remote Sensing in Managing the Environment. Proceedings (Cat. No.00CH37120).

[7]  G. Smith,et al.  Boreal Forest Monitoring with ERS Coherence , 2000 .

[8]  Kamal Sarabandi,et al.  Estimation of forest biophysical characteristics in Northern Michigan with SIR-C/X-SAR , 1995, IEEE Trans. Geosci. Remote. Sens..

[9]  M. Nilsson,et al.  Regional forest biomass and wood volume estimation using satellite data and ancillary data , 1999 .

[10]  J.T. Pulliainen,et al.  Seasonal dynamics of C-band backscatter of boreal forests with applications to biomass and soil moisture estimation , 1996, IEEE Trans. Geosci. Remote. Sens..

[11]  Jan Askne,et al.  Forest Insar Decorrelation and Classification Properties , 1997 .

[12]  M. Schwabisch,et al.  Improvement of phase and coherence map quality using azimuth prefiltering: examples from ERS-1 and X-SAR , 1995, 1995 International Geoscience and Remote Sensing Symposium, IGARSS '95. Quantitative Remote Sensing for Science and Applications.

[13]  川村 宏,et al.  "Space at the Service of our Environment"シンポジウム報告 , 1993 .

[14]  Martti Hallikainen,et al.  Retrieval of biomass in boreal forests from multitemporal ERS-1 and JERS-1 SAR images , 1999, IEEE Trans. Geosci. Remote. Sens..

[15]  P.B.G. Dammert,et al.  Decorrelation mechanisms in C-band SAR interferometry over boreal forest , 1996, Remote Sensing.

[16]  J. Hyyppä,et al.  Accuracy comparison of various remote sensing data sources in the retrieval of forest stand attributes , 2000 .

[17]  J. Fransson.  Estimation of stem volume in boreal forests using ERS-1 C- and JERS-1 L-band SAR data , 1999 .

[18]  Maurizio Santoro,et al.  Retrieval of Biomass in Boreal Forest from Multi-temporal ERS-1 / 2 Interferometry , 1999 .

[19]  R. Colwell.  Remote sensing of the environment , 1980, Nature.

[20]  U. Soederberg.  Functions for forecasting of timber yields. Increment and form height for individual trees of native species in Sweden [tree growth models, individual tree growth, basal area increment, form height functions, long term forecasting, mortality] , 1986 .

[21]  Shaun Quegan,et al.  Retrieval of Bio- and Geo-Physical Parameters from SAR Data for Land Applications. , 2002 .

[22]  F. Ulaby,et al.  Vegetation modeled as a water cloud , 1978 .

[23]  A. Luckman,et al.  The use of coherence information from ERS tandem pairs for determining forest stock volume in SIBERIA , 2000, IGARSS 2000. IEEE 2000 International Geoscience and Remote Sensing Symposium. Taking the Pulse of the Planet: The Role of Remote Sensing in Managing the Environment. Proceedings (Cat. No.00CH37120).

[24]  Jan Askne,et al.  Interferometric SAR observations of forested areas , 1997 .

[25]  T. Le Toan,et al.  Relating forest parameters to interferometric data , 1996, IGARSS '96. 1996 International Geoscience and Remote Sensing Symposium.

[26]  Juha Hyyppä,et al.  The seasonal behavior of interferometric coherence in boreal forest , 2001, IEEE Trans. Geosci. Remote. Sens..

[27]  Patrik Dammert.  Spaceborne SAR Interferometry: Theory and Applications , 1999 .

[28]  Johan Swärd,et al.  Designing a new national forest survey for Sweden , 1987 .

[29]  Johan E. S. Fransson,et al.  Stem volume estimation in boreal forests using ERS-1/2 coherence and SPOT XS optical data , 2001 .

[30]  Fabio Rocca,et al.  The wavenumber shift in SAR interferometry , 1994, IEEE Trans. Geosci. Remote. Sens..