File Download

There are no files associated with this item.

  Links for fulltext
     (May Require Subscription)
Supplementary

Article: Radiometric measurements of gap probability in conifer tree canopies

TitleRadiometric measurements of gap probability in conifer tree canopies
Authors
Issue Date1990
Citation
Remote Sensing of Environment, 1990, v. 34, n. 3, p. 179-192 How to Cite?
AbstractMeasurements of gap probability, defined as the probability that a photon of direct illumination at a given zenith angle will penetrate a tree canopy, were made for some moderate-sized, open-grown conifers of varying species in the National Arboretum, Washington, D.C. The measurements were collected by ratioing the standardizing readings in red and near-infrared bands of two radiometers with 6° fields of view that were pointed directly at the sun. One radiometer was located within the shadow of the conifer tree; the other was placed outside of the shadow. The path length associated with each radiometric measurement was calculated by fitting a simple conical geometric model to each tree from measurements of tree height and width. The radiometric measurements are best fit by a binomial model in which sunlight is either unobstructed or fully attenuated, and analysis show that the gap probability, which is taken as the mean of the binomial, fits a negative exponential function of path length quite well. The conifer shadow, then, is an object of almost uniform darkness with some bright holes or gaps that are found near the shadow's edge but rapidly disappear toward the shadow's center. © 1990.
Persistent Identifierhttp://hdl.handle.net/10722/321200
ISSN
2023 Impact Factor: 11.1
2023 SCImago Journal Rankings: 4.310
ISI Accession Number ID

 

DC FieldValueLanguage
dc.contributor.authorAlbers, Bryan J.-
dc.contributor.authorStrahler, Alan H.-
dc.contributor.authorLi, Xiaowen-
dc.contributor.authorLiang, Shunlin-
dc.contributor.authorClarke, Keith C.-
dc.date.accessioned2022-11-03T02:17:18Z-
dc.date.available2022-11-03T02:17:18Z-
dc.date.issued1990-
dc.identifier.citationRemote Sensing of Environment, 1990, v. 34, n. 3, p. 179-192-
dc.identifier.issn0034-4257-
dc.identifier.urihttp://hdl.handle.net/10722/321200-
dc.description.abstractMeasurements of gap probability, defined as the probability that a photon of direct illumination at a given zenith angle will penetrate a tree canopy, were made for some moderate-sized, open-grown conifers of varying species in the National Arboretum, Washington, D.C. The measurements were collected by ratioing the standardizing readings in red and near-infrared bands of two radiometers with 6° fields of view that were pointed directly at the sun. One radiometer was located within the shadow of the conifer tree; the other was placed outside of the shadow. The path length associated with each radiometric measurement was calculated by fitting a simple conical geometric model to each tree from measurements of tree height and width. The radiometric measurements are best fit by a binomial model in which sunlight is either unobstructed or fully attenuated, and analysis show that the gap probability, which is taken as the mean of the binomial, fits a negative exponential function of path length quite well. The conifer shadow, then, is an object of almost uniform darkness with some bright holes or gaps that are found near the shadow's edge but rapidly disappear toward the shadow's center. © 1990.-
dc.languageeng-
dc.relation.ispartofRemote Sensing of Environment-
dc.titleRadiometric measurements of gap probability in conifer tree canopies-
dc.typeArticle-
dc.description.naturelink_to_subscribed_fulltext-
dc.identifier.doi10.1016/0034-4257(90)90067-V-
dc.identifier.scopuseid_2-s2.0-0025659598-
dc.identifier.volume34-
dc.identifier.issue3-
dc.identifier.spage179-
dc.identifier.epage192-
dc.identifier.isiWOS:A1990FD28000003-

Export via OAI-PMH Interface in XML Formats


OR


Export to Other Non-XML Formats