The Spatial Distribution of Apis Dorsata Host Plants Using an Integrated Geographical Information System-Remote Sensing Approach

Abstract

Apis dorsata is one of the important honeybee species in tropical and subtropical regions that forages on various plants including herbs, grasses, forest trees and plantation trees. However, information on the spatial distribution of various pollen sources of Apis dorsata is still lacking. This study aimed at mapping the spatial distribution of the major honeybee plants that serve as pollen sources to Apis dorsata using an integrated Geographical Information System (GIS)-Remote Sensing (RS) approach. Mapping of pollen sources was based on SPOT-5 satellite imagery within a GIS environment. The SPOT-5 imagery was enhanced, classified and vectorized using ENVI 4.7. Image classification techniques were used to separate the pollen sources into six classes. Ten observation plots, each measuring 10×10 m, were established for each pollen source class using a randomized sampling technique. Results showed that Melaleuca cajuputi covered a total of 2,398.8 ha (5.5%), Acacia sp. 11,377.8 ha (25.9%), Elaeis guineensis 19745.1 ha (44.9%), non-vegetation 4,647.2 ha (10.6%), water bodies 973.5 ha (2.2%) and cloud/haze/shadow 4830.5 ha (10.6%). The overall classification accuracy was 91.5% and the Kappa coefficient was 0.8. The GIS-RS map showed that almost all of the Apis dorsata nesting sites were located in the Elaeis guineensis area. This study clearly demonstrates that Apis dorsata prefers to build its nest in close proximity to the pollen source.