Greenness in semi-arid areas across the globe 1981-2007 - an Earth Observing Satellite based analysis of trends and drivers

REMOTE SENSING OF ENVIRONMENT

卷:121

Article

Fensholt, Rasmus¹  Langanke, Tobias¹  Rasmussen, Kjeld¹  Reenberg, Anette¹  Prince, Stephen D.²  Tucker, Compton³  Scholes, Robert J.⁴  Le, Quang Bao^5,6  Bondeau, Alberte^7,16  Eastman, Ron⁸  Epstein, Howard⁹  Gaughan, Andrea E.¹⁰  Hellden, Ulf¹⁵  Mbow, Cheikh¹¹  Olsson, Lennart¹⁵  Paruelo, Jose^12,13  Schweitzer, Christian¹⁴  Seaquist, Jonathan¹⁵  Wessels, Konrad⁴ 

[1] Univ Copenhagen, Dept Geog & Geol, DK-1350 Copenhagen, Denmark

[2] Univ Maryland, Dept Geog, College Pk, MD 20742 USA

[3] NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA

[4] CSIR, ZA-0001 Pretoria, South Africa

[5] Univ Bonn, Ctr Dev Res ZEF, D-53113 Bonn, Germany

[6] ETH, Inst F Umweltentscheidungen, CH-8092 Zurich, Switzerland

[7] Potsdam Inst Climate Impact Res, D-14412 Potsdam, Germany

[8] Clark Univ, Grad Sch Geog, Worcester, MA 01610 USA

[9] Univ Virginia, Dept Environm Sci, Charlottesville, VA 22904 USA

[10] Univ Florida, Dept Geog, Gainesville, FL 32611 USA

[11] Univ Cheikh Anta Diop Dakar, Inst Sci Environm, Dakar, Senegal

[12] Univ Buenos Aires, Fac Agron IFEVA, RA-1417 Buenos Aires, DF, Argentina

[13] Consejo Nacl Invest Cient & Tecn, RA-1417 Buenos Aires, DF, Argentina

[14] UFZ Helmholtz Ctr Environm Res, Dept Computat Landscape Ecol CLE, D-04318 Leipzig, Germany

[15] Lund Univ, Dept Earth & Ecosyst Sci, S-22362 Lund, Sweden

[16] CNRS, Inst Mediterraneen Biodivers & Ecol Marine & Cont, Mediterranean Inst Biodivers & Ecol, IRD 237,UMR 7263, F-13545 Aix En Provence 04, France

关键词: AVHRR GIMMS NDVI;    MODIS NDVI;    Semi-arid;    Vegetation greenness;    Phenology;    Precipitation;    Air temperature;    Incoming shortwave radiation;   

DOI  :  10.1016/j.rse.2012.01.017

来源: Elsevier

【 摘 要 】

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. (c) 2012 Elsevier Inc. All rights reserved.

【 授权许可】

Free