ABSTRACT
In this chapter, we examine the recent trends in remote sensing for mapping and monitoring species invasions. With the rapid pace of globalization, plant and animal species are being introduced into new territories at an alarming rate. Many of these species not only have devastating impacts on the ecosystems in which they are introduced but also generate huge economic losses through decreased ecosystem services and costly eradication measures. Tackling invasions can be challenging because of their dynamic nature and large spatial extents. Aerospace imagery has proven to be a key tool for mapping, monitoring, and eradicating these nuisance species. This chapter introduces the problem of invasive species and the need for early detection and widespread monitoring through remote sensing. We then explore a case study of saltcedar (Tamarix spp.) to review the most advanced methods for discerning invasive species from both high-and medium-resolution data sets,
CONTENTS
13.1 Introduction ................................................................................. 308 13.2 Mapping and monitoring the regional invasion of saltcedar ......... 309
13.2.1 Detecting invasions using high-resolution satellite imagery .............................................................................311 13.2.1.1 Band selection ...................................................... 313 13.2.1.2 Image classication............................................... 313 13.2.1.3 Results .................................................................. 315
13.2.2 Detecting invasions from medium spatial and spectral resolution data ................................................................... 316 13.2.2.1 Incorporating species variability ........................... 317 13.2.2.2 Improved accuracy for detecting incipient
invasions ............................................................... 318 13.2.3 Ecological interpretation of geospatial data ....................... 320
13.3 Conclusion .................................................................................... 323 References ............................................................................................. 324
discuss the development of a novel classication technique that is particularly well suited for discriminating the species-level variation needed to discern invasions, and conclude with a discussion on how to interpret these types of advanced remote-sensing classications to derive useful and pertinent ecological information that can be applied to target eradication efforts.
