AERIAL SENSING AND PHOTOGRAPHIC STUDY OF THE EL VERDE RAIN FOREST PUERTO RICO.
Abstract
Aerial and ground photographs were taken over a 2-year period of sites in the El Verde rain forest to record the consistency of the vegetational patterns in untreated sites and the changes that occurred following gamma irradiation. Four emulsions were used: panchromatic infrared, false color transparency and color transparency. Densitometry was used to evaluate color film and the vegetation response to 3 months of radiation. The color emulsions provided the sharpest indication of damage to vegetation and the succession following treatment. Hemispherical photography of the canopy was evaluated in terms of a canopy cover index defined as per cent of light passing through the negative in a 90-degree cone area. Control stations were remarkably constant in all photography, establishing the stability and slow natural changes in rain forest structure. Spectral light measurements within the forest confirmed the predominance of far red shade light. Compared to similar studies on the chronic irradiated forest at Brookhaven National Laboratory the El Verde results were less distinct. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1969
- Accession Number
- AD0703123
Entities
People
- David M. Atwood
- Philip L. Johnson
Organizations
- Cold Regions Research and Engineering Laboratory