Mapping desertification extent DESIRE Project Harmonised Information System http://www.desire-his.eu/index.php/en/study-site-contexts/wp12-assessment-and-mapping-thematicmenu-166 Thu, 22 Sep 2016 20:26:27 +0000 Joomla! 1.5 - Open Source Content Management en-gb WOCAT tool for mapping land degradation and land conservation http://www.desire-his.eu/index.php/en/study-site-contexts/wp12-assessment-and-mapping-thematicmenu-166/162-wocat-tool-for-mapping-land-degradation-and-land-conservation http://www.desire-his.eu/index.php/en/study-site-contexts/wp12-assessment-and-mapping-thematicmenu-166/162-wocat-tool-for-mapping-land-degradation-and-land-conservation Editors: Hanspeter Liniger, Godert van Lynden, Freddy Nachtergaele, Gudrun Schwilch

Copyright © 2008: CDE/WOCAT, FAO/LADA, ISRIC

 

DESIRE has used the WOCAT method for mapping land degradation and sustainable land management in each of the study sites. The method was originally developed in the GLASOD project, but has been refined and developed with each successive set of applications (WOCAT, WOCAT/LADA, DESIRE).

 

For each distinctive land use type, the method evaluates

  • what type of land degradation is happening, where and why, and
  • what forms of land conservation practices are being used.

 

The method is designed to be used by an interdisciplinary team of specialists in subjects related to land degradation, land management, land use and soil and water conservation. The team first develops a base map (usually based on land use) then uses a questionnaire to gather the necessary data on land degradation and conservation for each land use system. The method is fully described in the document that can be downloaded at the bottom of this page

 

Once collected, the data may be entered in the on-line WOCAT mapping database (registration required) from which the various maps are generated.

 

The area to be mapped is divided into distinctive land use systems. Trends in changes in the area covered by easy land use and also its intensity are determined.

 

For each land use system, the type, extent, degree, impact on ecosystem services, direct and indirect causes of degradation are determined.

 

For each land use system, the type, extent, effectiveness, impact on ecosystem services and type of degradation addressed are determined for all land conservation practices used in the area.

 

More details ... download the full mapping methodology

 

English: icon Mapping land degradation and SLM (QM) (798.48 kB)

Arabic: icon Mapping land degradation and SLM (QM)_Arabic (1.07 MB)
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medesdesire@googlemail.com (Jane Brandt) Mapping desertification extent Mon, 31 Mar 2008 13:51:33 +0000
Spatial extent of degradation and conservation in DESIRE study sites http://www.desire-his.eu/index.php/en/study-site-contexts/wp12-assessment-and-mapping-thematicmenu-166/523-spatial-extent-of-degradation-and-conservation-in-desire-study-sites http://www.desire-his.eu/index.php/en/study-site-contexts/wp12-assessment-and-mapping-thematicmenu-166/523-spatial-extent-of-degradation-and-conservation-in-desire-study-sites Authors: Godert WJ van Lynden, Stephan Mantel (ISRIC - World Soil Information), Rudi Hessel (Alterra)

 

Two parallel and complementary methods were used to map the extent of desertification and restoration measures in the study areas:

  • The WOCAT mapping method, based on participatory assessment;
  • The GLADA mapping method, using NDVI analysis of a 26 year time series as has been applied in the LADA project.

 

WOCAT mapping method (sample results)

 

1. Degree and extent of degradation in study sites

The graph shows that moderate and high degrees of degradaton are fairly common in most sites, but that some sites (e.g. Botswana, Spain, Tunisia, Turkey) are affected by more serious degradation than others. Example land degradation map from the Morocco study site.

 

2. Extent and effectiveness of conservation measures in study sites

On average, conservation measures are moderately to highly effective in most sites. Exceptions are Crete (Greece), Rendina (Italy) and Mação (Portugal) where effectiveness is low. Example conservation effectiveness map from the China study site

 

GLADA mapping method (sample results)

 

Long term loss of ecosystem function and productivity is an important indicator of land degradation and desertification, and can be measured by a change in net primary productivity. As a proxy, the remotely sensed normalized difference vegetation index (NDVI) has been shown to be related to biophysical variables that control vegetation productivity. A simple annual sum NDVI indicator was calculated for the complete grwoing season. The positive trend shows in the above graph shwos that (for Botswana) there has been an increase in green biomass for the period 1981-2006, however this does not necessarily also correspond with land improvement.

 

More details ... read on-line or download the full report

WP1.2 Extent of degradation and conservation (Report 73 D121 Feb11)

WP1.2 Extent of degradation and conservation (Report 73 D121 Mar11)

 

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medesdesire@googlemail.com (Jane Brandt) Mapping desertification extent Fri, 11 Feb 2011 09:12:00 +0000