Title
A global map of rainfed cropland areas (GMRCA) at the end of last millennium using remote sensing
Abstract
The overarching goal of this study was to produce a global map of rainfed cropland areas (GMRCA) and calculate country-by-country rainfed area statistics using remote sensing data. A suite of spatial datasets, methods and protocols for mapping GMRCA were described. These consist of: (a) data fusion and composition of multi-resolution time-series mega-file data-cube (MFDC), (b) image segmentation based on precipitation, temperature, and elevation zones, (c) spectral correlation similarity (SCS), (d) protocols for class identification and labeling through uses of SCS R2-values, bi-spectral plots, space-time spiral curves (ST-SCs), rich source of field-plot data, and zoom-in-views of Google Earth (GE), and (e) techniques for resolving mixed classes by decision tree algorithms, and spatial modeling. The outcome was a 9-class GMRCA from which country-by-country rainfed area statistics were computed for the end of the last millennium. The global rainfed cropland area estimate from the GMRCA 9-class map was 1.13billion hectares (Bha). The total global cropland areas (rainfed plus irrigated) was 1.53Bha which was close to national statistics compiled by FAOSTAT (1.51Bha). The accuracies and errors of GMRCA were assessed using field-plot and Google Earth data points. The accuracy varied between 92 and 98% with kappa value of about 0.76, errors of omission of 2–8%, and the errors of commission of 19–36%.
Year
DOI
Venue
2009
10.1016/j.jag.2008.11.002
International Journal of Applied Earth Observation and Geoinformation
Keywords
Field
DocType
Global mapping,GMRCA,Rainfed and irrigated croplands,Remote sensing,Sub-pixel areas
Data point,Decision tree,Satellite imagery,Global Map,Remote sensing,Image segmentation,Sensor fusion,Elevation,Geography,Cartography,Agricultural land
Journal
Volume
Issue
ISSN
11
2
0303-2434
Citations 
PageRank 
References 
26
8.93
0
Authors
15