1-s2.0-S0924271614000288-main.pdf (3.04 MB)
Download file

Spectral monitoring of moorland plant phenology to identify a temporal window for hyperspectral remote sensing of peatland

Download (3.04 MB)
journal contribution
posted on 18.01.2017, 16:05 by Beth Cole, J. McMorrow, M. Evans
Recognising the importance of the timing of image acquisition on the spectral response in remote sensing of vegetated ecosystems is essential. This study used full wavelength, 350–2500 nm, field spectroscopy to establish a spectral library of phenological change for key moorland species, and to investigate suitable temporal windows for monitoring upland peatland systems. Spectral responses over two consecutive growing seasons were recorded at single species plots for key moorland species and species sown to restore eroding peat. This was related to phenological change using narrowband vegetation indices (Red Edge Position, Photochemical Reflectance Index, Plant Senescence Reflection Index and Cellulose Absorption Index); that capture green-up and senescence related changes in absorption features in the visible to near infrared and the shortwave infrared. The selection of indices was confirmed by identifying the regions of maximum variation in the captured reflectance across the full spectrum. The indices show change in the degree of variation between species occurring from April to September, measured for plant functional types. A discriminant function analysis between indices and plant functional types determines how well each index was able to differentiate between the plant functional groups for each month. It identifies April and July as the two months where the species are most separable. What is presented here is not one single recommendation for the optimal temporal window for operational monitoring, but a fuller understanding of how the spectral response changes with the phenological cycle, including recommendations for what indices are important throughout the year.

Funding

he authors would like to acknowledge the support of Moors for the Future Partnership for facilitating the work and in their role as CASE partner. The ASD field spectrometer was on loan from the NERC Field Spectroscopy Facility (FSF) (Loan No. 548.1207) support and guidance from Dr Alasdair Mac Arthur, was appreciated. Thanks also to The University of Salford and The University of Newcastle who also generously loaned equipment. The project was funded by a NERC CASE studentship with Natural England (NE/F013787/1).

History

Citation

ISPRS Journal of Photogrammetry and Remote Sensing, 90 (2014) 49–58

Author affiliation

/Organisation/COLLEGE OF SCIENCE AND ENGINEERING/Department of Geography

Version

VoR (Version of Record)

Published in

ISPRS Journal of Photogrammetry and Remote Sensing

Publisher

Elsevier for International Society for Photogrammetry and Remote Sensing (ISPRS)

issn

0924-2716

eissn

1872-8235

Acceptance date

26/01/2014

Copyright date

2014

Available date

18/01/2017

Publisher version

http://www.sciencedirect.com/science/article/pii/S0924271614000288

Language

en