Proxy global assessment of land degradation
Författare
Summary, in English
Land degradation is always With Lis but its causes, extent and severity are contested. We define land degradation as a long-term decline in ecosystem function and productivity, Which may be assessed using lone-term, remotely sensed normalized difference vegetation index (NDVI) data. Deviation from the norm may serve as a proxy assessment of land degradation and improvement - if other factors that may be responsible are taken into account. These other factors include rainfall effects which may be assessed by rain-use efficiency, calculated from NDVI and rainfall. Results from the analysis of the 23-year Global Inventory Modeling and Mapping Studies (GIMMS) NDVI data indicate declining rain-use efficiency-adjusted NDVI on ca. 24% of the global land area with degrading areas mainly in Africa south of the equator, South-East Asia and south China, north-central Australia, the Pampas and swaths of the Siberian and north American taiga; 1.5 billion people live in these areas. The results are very different from previous assessments which compounded what is happening now with historical land degradation. Economic appraisal can be undertaken when land degradation is expressed in terms of net primary productivity and the resultant data allow statistical comparison With other variables to reveal possible drivers.
Avdelning/ar
Publiceringsår
2008
Språk
Engelska
Sidor
223-234
Publikation/Tidskrift/Serie
Soil Use and Management
Volym
24
Issue
3
Länkar
Dokumenttyp
Artikel i tidskrift
Förlag
Wiley-Blackwell
Ämne
- Social Sciences Interdisciplinary
Nyckelord
- productivity
- net primary
- land degradation
- normalized difference vegetation index
- rain-use efficiency
- global relationships
Status
Published
ISBN/ISSN/Övrigt
- ISSN: 0266-0032