Recent studies using low-resolution satellite time series show that the Sahelian belt of West Africa is witnessing an increase in vegetation cover/biomass, called re-greening. However, detailed information on local processing and changes is rare or lacking. A multi-temporal set of Landsat images was used to produce land-cover maps for the years 2000 and 2007 in a semi-arid region of Niger, where an anomalous vegetation trend was previously detected. Several supervised classification approaches were tested: spectral classification of single Landsat data, temporal classification of normalized difference vegetation index time series from Landsat images, and two-step classification integrating both these approaches. The accuracy of the land-cover maps obtained ranges between 80% and 90% overall for the two-step classification approach. Comparison of the maps between the two years indicates a stable semi-arid region, where some change in hot spots exists despite a generally constant level of rainfall in the area during this period. In particular, the Dallol Bosso fossil valley highlights an increase in cultivated land, while a decrease in herbaceous vegetation was observed outside the valley where rangeland is the predominant natural landscape.
Land-use and land-cover change detection in a semi-arid area of Niger using multi-temporal analysis of Landsat images / F. Nutini, M. Boschetti, P. Brivio, S. Bocchi, M. Antoninetti. - In: INTERNATIONAL JOURNAL OF REMOTE SENSING. - ISSN 0143-1161. - 34:13(2013 Jul 10), pp. 4769-4790.
|Titolo:||Land-use and land-cover change detection in a semi-arid area of Niger using multi-temporal analysis of Landsat images|
|Parole Chiave:||land-use; LANDSAT; semi-arid area; vegetation cover|
|Settore Scientifico Disciplinare:||Settore AGR/02 - Agronomia e Coltivazioni Erbacee|
|Data di pubblicazione:||10-lug-2013|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1080/01431161.2013.781702|
|Appare nelle tipologie:||01 - Articolo su periodico|