Abstract
High-resolution airborne imaging spectroscopy represents a promising avenue for mapping the spread of invasive tree species through native forests, but for this technology to be useful to forest managers there are two main technical challenges that must be addressed: (1) mapping a single focal species amongst a diverse array of other tree species; and (2) detecting early outbreaks of invasive plant species that are often hidden beneath the forest canopy. To address these challenges, we investigated the performance of two single-class classification frameworks—Biased Support Vector Machine (BSVM) and Mixture Tuned Matched Filtering (MTMF)—to estimate the degree of Psidium cattleianum incidence over a range of forest vertical strata (relative canopy density). We demonstrate that both BSVM and MTMF have the ability to detect relative canopy density of a single focal plant species in a vertically stratified forest, but they differ in the degree of user input required. Our results suggest BSVM as a promising method to disentangle spectrally-mixed classifications, as this approach generates decision values from a similarity function (kernel), which optimizes complex comparisons between classes using a dynamic machine learning process.
Highlights
Forest ecosystems invaded by exotic plant species can experience changes on native species abundance and richness [1,2], altered ecosystem function [3,4], or economic losses [5]
Mixture Tuned Matched Filtering (MTMF) showed better performance using a threshold mapping approach than a volumetric approach, and the opposite occurred with Biased Support Vector Machine (BSVM)
The relationship between field and remote sensing estimates were slightly better using the MTMF—threshold approach (R2 = 0.86; RMSE = 0.9) than BSVM—volumetric approach (R2 = 0.85; RMSE = 0.10). These results indicate the capability of remote sensing data to estimate the location of invasive trees in both upper canopy and subcanopy positions, and they highlight the potential use of this BSVM as a spectral unmixing method
Summary
Forest ecosystems invaded by exotic plant species can experience changes on native species abundance and richness [1,2], altered ecosystem function [3,4], or economic losses [5]. These and other negative impacts of invasion may vary as landscapes are gradually invaded [6]. Effective methods to map, monitor, and estimate the gradual spread of invasive plant species (invasion dominance) are needed to further understand the impacts of these species and manage their unwanted consequences [7,8].
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
