c7a67bd5-49da-44e7-be0e-6b0b9fd38d6a eng Zhanguo Bai 2012-02-22T15:06:30 ISO 19115:2003/19139 1.0 2 1870 0.072727 4943 0.072727 false GCS_WGS_1984 Global Change in Rain-Use Efficiency 1981-2003 2008-10-22T07:00:00 First edition Rain-use efficiency (RUE) is considered to make allowance for the effect of fluctuations in rainfall on biomass productivity. RUE may fluctuate dramatically in the short term - often, there is a sharp decline in RUE in a wet year and we assume that the vegetation, whether cultivated or semi-natural, cannot make immediate use of the additional rain. However, where rainfall is the main limiting factor on biomass productivity, we judge that the long-term trend of RUE is a good indicator of land degradation or improvement (Houerou 1984, 1988, 1989; Snyman 1998; Illius and O'Connor 1999; O'Connor and others 2001). RUE also accommodates the effects of local variations in slope, soil and vegetation (Justice and others 1991). Rain-use efficiency was calculated as the ratio of annual sum NDVI and station-observed annual rainfall. The rain-use efficiency, i.e. production per unit of rainfall, is analysed to present the spatial pattern, temporal trends and confidence over the period; it is also used to adjust the NDVI trend. Food and Agriculture Organization of United Nations - HQs Viale delle Terme di Caracalla Rome 00153 Italy ISRIC - World Soil Information +31 (0)317 483 735 Duivendaal 9 Wageningen Wageningen 6701 AR The Netherlands soil.isric@wur.nl UN FAO - HQs Director of Land and Water Division Viale delle Terme di Caracalla Rome 00153 Italy NRL-Director@fao.org Fig3_s.png thumbnail png Fig3.gif large_thumbnail gif NDVI Land degradation Land improvement Remote sensing Rain-use efficiency GLADA World eng environment 1951-01-01T16:35:00 2003-12-31T08:00:00 -180 180 -90 90 Within the FAO program Land Degradation Assessment in Drylands (LADA), the present "Global Assessment of Land Degradation and Improvement" uses remote sensing to identify areas where significant biological change is happening, both hot spots of land degradation and bright spots of land improvement. In the next phase of the program, hot spots and bright spots will be further characterised in the field by national teams. http://www.isric.org WWW:LINK-1.0-http--link ISRIC - World Soil Information website http://www.fao.org/nr/lada/index.php?/Global.html WWW:LINK-1.0-http--link LADA - Land Degradation Assessment in Drylands - FAO 2008 Web site http://www.fao.org:80/geonetwork/srv/en/resources.get?id=37051&fname=Global change in RUE - Fig 3.zip&access=private WWW:DOWNLOAD-1.0-http--download Global change in RUE - Fig 3.zip Global change in rain-use efficiency 1981-2003 - IMG format http://www.fao.org:80/geonetwork/srv/en/resources.get?id=37051&fname=GLADA Report 5.pdf&access=private WWW:DOWNLOAD-1.0-http--download GLADA Report 5.pdf GLADA Report 5 - Global Assessment of Land Degradation and Improvement http://data.fao.org/maps/wms?styles=geonetwork_fig3_37051_style OGC:WMS-1.1.1-http-get-map GEONETWORK:fig3_37051 Global Change in Rain-Use Efficiency 1981-2003 Last Updated 2008-10-30T15:34:00