When flowering, leafy spurge (Euphorbia esula L.) has conspicuous yellow-green bracts that are spectrally distinct from other vegetation and may be distinguished with hyperspectral remote sensing. In July 1999, Airborne Visible Infrared Imaging Spectrometer (AVIRIS) data were acquired in northeastern Wyoming, near Devils Tower National Monument. Using the reflectance spectrum of flowering leafy spurge, leafy spurge occurrence was determined using a new method of spectral mixture analysis, Mixture Tuned Matched Filtering (MTMF). Ground reference data (146 sites) were obtained 2 weeks before and after AVIRIS overflight to test the classification accuracy of leafy spurge. For 3 land cover types: mixed prairie, riparian, and coniferous woodlands, the presence or absence leafy spurge was detected with an overall accuracy of 95% using a 0.10 threshold for detection. Differences in classification thresholds resulted in a trade-off between false positives, pixels that were mapped as leafy spurge but did not contain leafy spurge on the ground, and false negatives, areas that had leafy spurge on the ground but were not mapped as leafy spurge. Detection of leafy spurge occurrence was best for mixed prairie and riparian cover types, and somewhat less successful for conifer woodlands because of interference from tree crowns and their shadows. The advantage of the MTMF technique is it allows automated processing of hyperspectral imagery to generate accurate maps of leafy spurge occurrence.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 57 • No. 1