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Estimating nitrogen in mixed forests from HyMap data using band-depth analysis and branch-and-bound algorithm


Huber, Silvia; Zimmermann, Niklaus E; Kneubühler, Mathias; Itten, Klaus I (2005). Estimating nitrogen in mixed forests from HyMap data using band-depth analysis and branch-and-bound algorithm. In: 9th International Symposium on Physical Measurements and Signatures in Remote Sensing (ISPMSRS), Beijing, China, 17 October 2005 - 19 October 2005, 533-535.

Abstract

Spatial information of nitrogen concentration (Nc) is of great interest because of its role in photosynthesis, ecosystem productivity and thus influences global cycling of carbon and oxygen. Imaging spectroscopy offers a means to assess this compound. Nc was estimated in mixed forests in Switzerland from airborne HyMap data using band-depth analysis. Instead of stepwise regression, an exhaustive search algorithm has been applied to select significant wavebands in order to build relationships between transformed reflectance and fieldmeasured Nc. This study confirms that partitioning data into vegetation types yielded in higher R2. R2 was largest for the homogeneous coniferous sample. A preclassification of the HyMap images is therefore recommended. The tested branch-and-bound algorithm performed well in selecting important known nitrogen absorption wavebands. A comparison with other subset selection methods is planned.

Spatial information of nitrogen concentration (Nc) is of great interest because of its role in photosynthesis, ecosystem productivity and thus influences global cycling of carbon and oxygen. Imaging spectroscopy offers a means to assess this compound. Nc was estimated in mixed forests in Switzerland from airborne HyMap data using band-depth analysis. Instead of stepwise regression, an exhaustive search algorithm has been applied to select significant wavebands in order to build relationships between transformed reflectance and fieldmeasured Nc. This study confirms that partitioning data into vegetation types yielded in higher R2. R2 was largest for the homogeneous coniferous sample. A preclassification of the HyMap images is therefore recommended. The tested branch-and-bound algorithm performed well in selecting important known nitrogen absorption wavebands. A comparison with other subset selection methods is planned.

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Additional indexing

Item Type:Conference or Workshop Item (Paper), refereed, original work
Communities & Collections:07 Faculty of Science > Institute of Geography
Dewey Decimal Classification:910 Geography & travel
Language:English
Event End Date:19 October 2005
Deposited On:26 Aug 2014 15:56
Last Modified:05 Apr 2016 18:21
Publisher:ISPRS
Series Name:International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences
Number:XXXVI
ISSN:1682-1750
Free access at:Official URL. An embargo period may apply.
Official URL:http://www.wageningenur.nl/en/Publication-details.htm?publicationId=publication-way-333432393733
Permanent URL: https://doi.org/10.5167/uzh-98426

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