Wavelet estimation of plant spatial patterns in multitemporal aerial photography
Abstract:Wavelet analysis represents a powerful set of image processing techniques that have considerable potential to quantify ecologically relevant patterns at multiple scales. This paper provides a preliminary assessment of whether two‐dimensional wavelets convolved with 1 m panchromatic aerial photography can be used to detect automatically the location and crown diameters of western juniper ( Juniperus occidentalis ) plants as they encroach upon a sagebrush ( Artemisia spp.) steppe landscape. The juniper crown diameters derived from wavelet analysis produced a strong correlation with crown diameters measured via comparable hand‐digitizing in a geographic information system (r = 0.96, n = 69) with a 5% commission and an 8% omission error. Through comparison with historical photography, we found that juniper plant cover increased 2.7 fold (from 2.7% to 7.3% total cover) during the period from 1939 to 1998 within the 15 ha study area. This approach has considerable potential for the long‐term monitoring of vegetation change via aerial photograph and other remotely sensed imagery.
Document Type: Research Article
Affiliations: 1: Department of Rangeland Ecology and Management, University of Idaho, Moscow, ID 83844 2: Department of Mechanical and Manufacturing Engineering, Trinity College, Dublin, Ireland 3: Department of Forest Resources, University of Idaho, Moscow, ID 83844
Publication date: May 1, 2006