The impact of vegetation on lithological mapping using airborne multispectral data: a case study for the North Troodos Region, Cyprus

Grebby, Stephen; Cunningham, Dickson; Tansey, Kevin; Naden, Jonathan. 2014 The impact of vegetation on lithological mapping using airborne multispectral data: a case study for the North Troodos Region, Cyprus. Remote Sensing, 6 (11). 10860-10887. 10.3390/rs61110860

Before downloading, please read NORA policies.

Preview

Text (Open Access Paper)
OAE14_414.pdf - Published Version
Available under License Creative Commons Attribution.
Download (7MB) | Preview

Official URL: http://dx.doi.org/10.3390/rs61110860

Abstract/Summary

Vegetation cover can affect the lithological mapping capability of space- and airborne instruments because it obscures the spectral signatures of the underlying geological substrate. Despite being widely accepted as a hindrance, few studies have explicitly demonstrated the impact vegetation can have on remote lithological mapping. Accordingly, this study comprehensively elucidates the impact of vegetation on the lithological mapping capability of airborne multispectral data in the Troodos region, Cyprus. Synthetic spectral mixtures were first used to quantify the potential impact vegetation cover might have on spectral recognition and remote mapping of different rock types. The modeled effects of green grass were apparent in the spectra of low albedo lithologies for 30%–40% fractional cover, compared to just 20% for dry grass cover. Lichen was found to obscure the spectra for 30%–50% cover, depending on the spectral contrast between bare rock and lichen cover. The subsequent impact of vegetation on the remote mapping capability is elucidated by considering the outcomes of three airborne multispectral lithological classifications alongside the spectral mixing analysis and field observations. Vegetation abundance was found to be the primary control on the inability to classify large proportions of pixels in the imagery. Matched Filtering outperformed direct spectral matching algorithms owing to its ability to partially unmix pixel spectra with vegetation abundance above the modeled limits. This study highlights that despite the limited spectral sampling and resolution of the sensor and dense, ubiquitous vegetation cover, useful lithological information can be extracted using an appropriate algorithm. Furthermore, the findings of this case study provide a useful insight to the potential capabilities and challenges faced when utilizing comparable sensors (e.g., Landsat 8, Sentinel-2, WorldView-3) to map similar types of terrain.

Item Type:	Publication - Article
Digital Object Identifier (DOI):	10.3390/rs61110860
ISSN:	2072-4292
Date made live:	05 Feb 2015 13:19 +0 (UTC)
URI:	https://nora.nerc.ac.uk/id/eprint/509609

Item Type:

Publication - Article

Digital Object Identifier (DOI):

10.3390/rs61110860

ISSN:

2072-4292

Date made live:

05 Feb 2015 13:19 +0 (UTC)

URI:

https://nora.nerc.ac.uk/id/eprint/509609