Title
Analysis of the Scaling Effects in the Area-Averaged Fraction of Vegetation Cover Retrieved Using an NDVI-Isoline-Based Linear Mixture Model
Abstract
The spectral unmixing of a linear mixture model (LMM) with Normalized Difference Vegetation Index (NDVI) constraints was performed to estimate the fraction of vegetation cover (FVC) over the earth's surface in an effort to facilitate long-term surface vegetation monitoring using a set of environmental satellites. Although the integrated use of multiple sensors improves the spatial and temporal quality of the data sets, area-averaged FVC values obtained using an LMM-based algorithm suffer from systematic biases caused by differences in the spatial resolutions of the sensors, known as scaling effects. The objective of this study is to investigate the scaling effects in area-averaged FVC values using analytical approaches by focusing on the monotonic behavior of the scaling effects as a function of the spatial resolution. The analysis was conducted based on a resolution transformation model introduced recently by the authors in the accompanying paper (Obata et al., 2012). The maximum value of the scaling effects present in FVC values was derived analytically and validated numerically. A series of derivations identified the error bounds (inherent uncertainties) of the averaged FVC values caused by the scaling effect. The results indicate a fundamental difference between the NDVI and the retrieved FVC from NDVI, which should be noted for accuracy improvement of long-term observation datasets.
Year
DOI
Venue
2012
10.3390/rs4072156
REMOTE SENSING
Keywords
Field
DocType
fraction of vegetation cover,scaling effect,monotonicity,NDVI,resolution transformation model
Monotonic function,Data set,Satellite,Vegetation,Remote sensing,Normalized Difference Vegetation Index,Statistics,Geology,Scaling,Image resolution,Mixture model
Journal
Volume
Issue
ISSN
4
7
2072-4292
Citations 
PageRank 
References 
1
0.51
13
Authors
3
Name
Order
Citations
PageRank
Kenta Obata13715.95
Tomoaki Miura28318.25
Hiroki Yoshioka38323.06