IFEVA   02662
INSTITUTO DE INVESTIGACIONES FISIOLOGICAS Y ECOLOGICAS VINCULADAS A LA AGRICULTURA
Unidad Ejecutora - UE
artículos
Título:
Greenness in semi-arid areas across the globe 1981?2007 ? an Earth Observing Satellite based analysis of trends and drivers
Autor/es:
RASMUS FENSHOLT; TOBIAS LANGANKE; KJELD RASMUSSEN ; ANETTE REENBERG; STEPHEN D. PRINCE; COMPTON TUCKER; ROBERT J. SCHOLES; QUANG BAO LE ; ALBERTE BONDEAU ; RON EASTMAN; HOWARD EPSTEIN; ANDREA E. GAUGHAN; ULF HELLDEN; CHEIKH MBOW; LENNART OLSSON; JOSE PARUELO; CHRISTIAN SCHWEITZER; JONATHAN SEAQUIST; KONRAD WESSELS
Revista:
REMOTE SENSING OF ENVIRONMENT
Editorial:
ELSEVIER SCIENCE INC
Referencias:
Lugar: Amsterdam; Año: 2012 vol. 121 p. 144 - 158
ISSN:
0034-4257
Resumen:
Semi-arid areas, defined as those areas of the world where water is an important limitation for plant growth,
have become the subject of increased interest due to the impacts of current global changes and sustainability
of human lifestyles. While many ground-based reports of declining vegetation productivity have been published
over the last decades, a number of recent publications have shown a nuanced and, for some regions,
positive picture. With this background, the paper provides an analysis of trends in vegetation greenness of
semi-arid areas using AVHRR GIMMS from 1981 to 2007. The vegetation index dataset is used as a proxy
for vegetation productivity and trends are analyzed for characterization of changes in semi-arid vegetation
greenness. Calculated vegetation trends are analyzed with gridded data on potential climatic constraints to
plant growth to explore possible causes of the observed changes. An analysis of changes in the seasonal variation
of vegetation greenness and climatic drivers is conducted for selected regions to further understand
the causes of observed inter-annual vegetation changes in semi-arid areas across the globe. It is concluded
that semi-arid areas, across the globe, on average experience an increase in greenness (0.015 NDVI units
over the period of analysis). Further it is observed that increases in greenness are found both in semi-arid
areas where precipitation is the dominating limiting factor for plant production (0.019 NDVI units) and in
semi-arid areas where air temperature is the primarily growth constraint (0.013 NDVI units). Finally, in
the analysis of changes in the intra-annual variation of greenness it is found that seemingly similar increases
in greenness over the study period may have widely different explanations. This implies that current generalizations,
claiming that land degradation is ongoing in semi-arid areas worldwide, are not supported by the
satellite based analysis of vegetation greenness.
© 2012 Elsevier Inc. All rights reserved.