NASA LogoNTRSNTRS - NASA Technical Reports ServerSearchmore_vertCollectionsAboutNewsHelpLogin Back to ResultsBOREAS TE-9 In Situ Understory Spectral Reflectance Within the NSAThe Boreal Ecosystem-Atmospheric Study (BOREAS) TE-9 (Terrestrial Ecology) team collected several data sets related to chemical and photosynthetic properties of leaves in boreal forest tree species. Spectral reflection coefficients of the forest understory at the ground level, in three boreal forest sites of Northern Manitoba (56 N latitude and 98 W longitude), were obtained and analyzed in 1994. In particular, angular variation of the reflection coefficients in the old jack pine and young jack pine forests, as well as nadir reflection coefficient in the young aspen forest, were investigated. The complexity of understory composition and the light patterns limited quantitative conclusions; however, a number of interesting trends in the behavior of the measured values can be inferred. In particular, the unique spectral profiles of lichens show very strongly in the old jack pine understory, yet are definitely less conspicuous for young jack pine, and virtually absent in the aspen forest. The angular variation of the reflection coefficient by the young pine understory seems to be significantly toned down by fine-structured branches and their shadows. Our study also indicates how difficult the ground reflection coefficient problem in a forest is, compared to certain previously investigated areas that have a more uniform appearance, such as prairie grassland, bare soil, or agricultural crops. This is due to several factors, generally typical of a forest environment, that may influence the overall understory reflection coefficient, including: (1) a strong diversity of the forest floor due to the presence of dead tree trunks, holes in the ground, patches of different types of vegetation or litter, etc.; (2) pronounced 3-D structures at the ground level, such as shrubs, bushes, and young trees; and (3) an irregular shadow mosaic, which not only varies with the time of the day, causing intensity variations, but likely also effectively modifies the spectrum of the illuminating light and hence the reflection coefficient signal as well The data are stored in tabular ASCII files. The data files are available on a CD-ROM (see document number 20010000884), or from the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).Document ID20010004232Acquisition SourceGoddard Space Flight CenterDocument TypeTechnical Memorandum (TM)AuthorsHall, Forrest G.*(NASA Goddard Space Flight Center Greenbelt, MD United States)*Curd, Shelaine*(Raytheon Information Technology and Scientific Services Greenbelt, MD United States)*Supronowicz, Jan*(Laval Univ. Sainte-Foye, Quebec Canada)*Edwards, Geoffrey*(Laval Univ. Sainte-Foye, Quebec Canada)*Viau, Alain*(Laval Univ. Sainte-Foye, Quebec Canada)*Thomson, Keith*(Laval Univ. Sainte-Foye, Quebec Canada)*Date AcquiredSeptember 7, 2013Publication DateOctober 1, 2000Subject CategoryEarth Resources And Remote SensingReport/Patent NumberNASA/TM-2000-209891/VOL159NAS 1.15:209891/VOL159Rept-2000-03136-0/VOL159Funding Number(s)PROJECT: RTOP 462-33-01Distribution LimitsPublicCopyrightWork of the US Gov. Public Use Permitted.Available DownloadsNameType20010004232.pdfSTIcloud_downloadcontent_copyvisibilityRelated RecordsThere are no records associated with this record.visibility_offNo Preview Available
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