| Autor: |
Erickson, Bruce J., Johannsen, Chris J., Vorst, James J., Biehl, Larry L. |
| Předmět: |
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| Zdroj: |
Photogrammetric Engineering & Remote Sensing; Jun2004, Vol. 70 Issue 6, p717-722, 6p, 2 Diagrams, 4 Charts, 3 Graphs |
| Abstrakt: |
Assessing hail and wind damage to crops is a difficult, labor-intensive task. A quick and accurate method of determining losses could lead to better crop management decisions, more accurate insurance claim adjustment, and reduced expenses for the crop hail insurance industry. Radiometric data were collected in 1997, 1998, and 1999 in Indiana and Nebraska from field plots of maize, Zea mays L., subjected to varying levels of damage. Incremental differences in plant damage resulted in incremental differences in spectral responses. The red and near-infrared spectral bands provided the most discrimination among levels of damage. Classification of remotely sensed images by damage level was performed by extrapolating spectral information from areas where damage levels were known to adjacent unknown areas of damage. Depending on location, sensor, and date of data collection, it was possible to classify the degree of early-season stand loss at accuracies of 48 to 100 percent. For leaf loss during the late vegetative stages, it was possible to classify the degree of leaf loss at accuracies of 81 to 100 percent and, for leaf loss during the early reproductive stages, it was possible to classify damage at accuracies of 71 to 98 percent. These results indicate that remote sensing could be used to improve the accuracy of estimating crop damage as long as adequate ground reference for different levels of crop damage exists. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Supplemental Index |
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