Using RapidEye and MODIS data fusion to monitor vegetation dynamics in semi-arid rangelands in South Africa

Andreas Tewes, Frank Thonfeld, Michael Schmidt, Roelof J. Oomen, Xiaolin Zhu, Olena Dubovyk, Gunter Menz, Jürgen Schellberg

Research output: Journal article publicationJournal articleAcademic researchpeer-review

29 Citations (Scopus)

Abstract

Image time series of high temporal and spatial resolution capture land surface dynamics of heterogeneous landscapes. We applied the ESTARFM (Enhanced Spatial and Temporal Adaptive Reflectance Fusion Model) algorithm to multi-spectral images covering two semi-arid heterogeneous rangeland study sites located in South Africa. MODIS 250 m resolution and RapidEye 5 m resolution images were fused to produce synthetic RapidEye images, from June 2011 to July 2012. We evaluated the performance of the algorithm by comparing predicted surface reflectance values to real RapidEye images. Our results show that ESTARFM predictions are accurate, with a coefficient of determination for the red band 0.80 < R<sup>2</sup> < 0.92, and for the near-infrared band 0.83 < R<sup>2</sup> < 0.93, a mean relative bias between 6% and 12% for the red band and 4% to 9% in the near-infrared band. Heterogeneous vegetation at sub-MODIS resolution is captured adequately: A comparison of NDVI time series derived from RapidEye and ESTARFM data shows that the characteristic phenological dynamics of different vegetation types are reproduced well. We conclude that the ESTARFM algorithm allows us to produce synthetic remote sensing images at high spatial combined with high temporal resolution and so provides valuable information on vegetation dynamics in semi-arid, heterogeneous rangeland landscapes.
Original languageEnglish
Pages (from-to)6510-6534
Number of pages25
JournalRemote Sensing
Volume7
Issue number6
DOIs
Publication statusPublished - 1 Jan 2015
Externally publishedYes

Keywords

  • Data blending
  • ESTARFM
  • High spatial and temporal resolution
  • Image fusion
  • MODIS
  • RapidEye
  • Time series
  • Vegetation dynamics

ASJC Scopus subject areas

  • Earth and Planetary Sciences(all)

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