Woody and Herbaceous Vegetation Change across the Savannas of West Africa, 1982-2013
The WAVeTrends dataset is a 0.05 degree (5.55 km) vegetation change product, spanning the West African Sudano-Sahel region. It provides pixel-wise information on concurrent woody and herbaceous vegetation trends over a 32-year period (1982-2013). Change in woody vegetation was derived using long-term rain use efficiency (RUE) sensitivity, i.e., the per-pixel comparison of the difference of mean RUE between the first and last decades of the 32-year time series. Herbaceous vegetation change was defined by short-term RUE sensitivity, i.e., comparing the slope of the RUE relationship (productivity vs. precipitation) between both decades using per-pixel Analysis of Covariance (ANCOVA). Categorical vegetation change was then determined for each pixel using the direction of the change and a significance level of p<0.05. The use of RUE (the amount of biomass produced per unit of precipitation) for vegetation trend analysis in savanna regions relies on the assumption that rainfall is a significant positive driver of net production in drylands. Testing of this long-term productivity-rainfall relationship revealed that the assumption was not always met, therefore, validity flags are included for each pixel location.
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Original Metadata
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Complete Metadata
| @type | dcat:Dataset |
|---|---|
| accessLevel | public |
| bureauCode |
[ "026:00" ] |
| contactPoint |
{ "fn": "Earthdata Forum", "@type": "vcard:Contact", "hasEmail": "mailto:earthdata-support@nasa.gov" } |
| description | The WAVeTrends dataset is a 0.05 degree (5.55 km) vegetation change product, spanning the West African Sudano-Sahel region. It provides pixel-wise information on concurrent woody and herbaceous vegetation trends over a 32-year period (1982-2013). Change in woody vegetation was derived using long-term rain use efficiency (RUE) sensitivity, i.e., the per-pixel comparison of the difference of mean RUE between the first and last decades of the 32-year time series. Herbaceous vegetation change was defined by short-term RUE sensitivity, i.e., comparing the slope of the RUE relationship (productivity vs. precipitation) between both decades using per-pixel Analysis of Covariance (ANCOVA). Categorical vegetation change was then determined for each pixel using the direction of the change and a significance level of p<0.05. The use of RUE (the amount of biomass produced per unit of precipitation) for vegetation trend analysis in savanna regions relies on the assumption that rainfall is a significant positive driver of net production in drylands. Testing of this long-term productivity-rainfall relationship revealed that the assumption was not always met, therefore, validity flags are included for each pixel location. |
| distribution |
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| identifier | 10.3334/ORNLDAAC/1738 |
| keyword |
[ "earth-science-ecological-dynamics-biosphere-ecosystem-functions", "earth-science-ecosystems-biosphere-terrestrial-ecosystems", "earth-science-habitat-conversion-fragmentation-human-dimensions-reforestation-revegetation", "earth-science-precipitation-atmosphere-liquid-precipitation", "earth-science-vegetation-biosphere-vegetation-cover", "earth-science-vegetation-biosphere-vegetation-index" ] |
| license | https://www.usa.gov/government-works |
| modified | 2026-06-23 |
| programCode |
[ "026:000" ] |
| publisher |
{ "name": "ORNL_DAAC", "@type": "org:Organization" } |
| spatial |
"["CARTESIAN", [{"WestBoundingCoordinate": -17.1432, "NorthBoundingCoordinate": 17.4148, "EastBoundingCoordinate": 15.3068, "SouthBoundingCoordinate": 9.96476}]]"
|
| temporal | 1982-01-01/2013-12-31 |
| theme |
[ "Earth Science" ] |
| title | Woody and Herbaceous Vegetation Change across the Savannas of West Africa, 1982-2013 |
