| Resumo: |
Since the completion of the Navstar Global Positioning System (GPS) in 1995, the integration of GPS and Geographical Information Systems (GIS) technology has expanded to a great number of ecological and conservation applications. In tropical rain forest ecology, however, the technology has remained relatively neglected, despite its great potential. Notwithstanding cost, this is principally due to (1) the difficulty of quality satellite reception beneath a dense forest canopy, and (2) a degree of spatial error unacceptable to fine-scale vegetation mapping. Here, we report on the technical use of GPS/GIS in the rain forest of Kibale National Park, Uganda, and the methodology necessary to acquire high-accuracy spatial measurements. We conclude that the stringent operating parameters necessary for high accuracy were rarely obtained while standing beneath the rain forest canopy. Raising the GPS antenna to heights of 25–30 m resolved this problem, allowing swift data collection on the spatial dispersion of individual rain forest trees. We discuss the impact of the 1996 Presidential Decision Directive that suspended U.S. military-induced GPS error on 1 May 2000, and comment on the potential applications of GPS/GIS technology to the ecological study and conservation of tropical rain forests.
|
