Diagnosis of vegetation recovery within herbaceous sub-systems in the West African Sahel Region
Abstract
The West African Sahel (WAS) region is an extensive water limited environment that features a delicate balance of herbaceous and woody vegetation sub systems. These play an important role in the cycling of carbon while also supporting the dominant agro-pastoral human activities in the region. Quantifying the temporal trends in vegetation with regard to these two systems is therefore very important in assessing resource sustainability and food security. In water limited areas, rainfall is a primary driver of vegetation productivity and past watershed scale studies in the WAS region have shown that increase in the slope of the productivity-to-rainfall relationship is indicative of increasing cover and density of herbaceous plants. Given the importance of grazing resources to the region, we perform a wall-to-wall pixel based analysis of changing short-term vegetation sensitivity to changing annual rainfall (hereafter referred to as dS) to examine temporal trends in herbaceous vegetation health. Results indicate that 43% of the Sahelian region has experienced changes (P < 0.05) in herbaceous vegetation (dS). Areas with significant increases in dS are well distributed across the region, but with major concentrations in North-Central Senegal, South Western and Central Mali and South Western Niger. Positive dS is indicative of herbaceous vegetation recovery, in response to changing management and rainfall conditions that promote long-term herbaceous community recovery following degradation during the 1970-1980s droughts.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2017
- Bibcode:
- 2017AGUFMGC13I0854A
- Keywords:
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- 1616 Climate variability;
- GLOBAL CHANGE;
- 1632 Land cover change;
- GLOBAL CHANGE;
- 1640 Remote sensing;
- GLOBAL CHANGE;
- 1655 Water cycles;
- GLOBAL CHANGE