Stratifying land use/land cover for spatial analysis of disease ecology and risk: an example using object-based classification techniques

Geospat Health. 2007 Nov;2(1):15-28. doi: 10.4081/gh.2007.251.

Abstract

Landscape epidemiology has made significant strides recently, driven in part by increasing availability of land cover data derived from remotely-sensed imagery. Using an example from a study of land cover effects on hantavirus dynamics at an Atlantic Forest site in eastern Paraguay, we demonstrate how automated classification methods can be used to stratify remotely-sensed land cover for studies of infectious disease dynamics. For this application, it was necessary to develop a scheme that could yield both land cover and land use data from the same classification. Hypothesizing that automated discrimination between classes would be more accurate using an object-based method compared to a per-pixel method, we used a single Landsat Enhanced Thematic Mapper+ (ETM+) image to classify land cover into eight classes using both per-pixel and object-based classification algorithms. Our results show that the object-based method achieves 84% overall accuracy, compared to only 43% using the per-pixel method. Producer's and user's accuracies for the object-based map were higher for every class compared to the per-pixel classification. The Kappa statistic was also significantly higher for the object-based classification. These results show the importance of using image information from domains beyond the spectral domain, and also illustrate the importance of object-based techniques for remote sensing applications in epidemiological studies.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Agriculture / classification*
  • Animals
  • Communicable Diseases
  • Ecology*
  • Ecosystem
  • Hantavirus Infections / epidemiology
  • Hantavirus Infections / parasitology*
  • Orthohantavirus
  • Paraguay / epidemiology
  • Photography*
  • Risk Assessment
  • Spacecraft*