WOCAT tool for mapping land degradation and land conservation

2008-03-31T13:51:33Z

Editors: Hanspeter Liniger, Godert van Lynden, Freddy Nachtergaele, Gudrun Schwilch

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

Arabic: Mapping land degradation and SLM (QM)_Arabic (1.07 MB)

Spatial extent of degradation and conservation in DESIRE study sites

2011-02-11T09:12:00Z

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)

Mapping desertification extent

WOCAT tool for mapping land degradation and land conservation

Spatial extent of degradation and conservation in DESIRE study sites