Modeling and mapping the distribution and priority seed zone for the conservation of the vulnerable Vitellaria Paradoxa (Shea nut tree) in the Guinea savanna ecosystem

Abstract

Vitellaria paradoxa C.F. Gaertn is a native and valuable economic tree species found in the Guinea savanna ecosystem of West Africa. The majority of rural populations, especially women, depend on it for food, domestic energy (fuelwood), and as a source of employment and income. Unfortunately, the extensive felling of this tree species for charcoal production over the past decades poses a grave threat to both the environment and the livelihoods of people; therefore, efforts to restore and conserve the tree species are urgently required. The salient question here is where to obtain viable seeds for its propagation and restoration. This study applied remote sensing technology to extract vegetation-related phenotypic data from satellite images (Landsat 8 - 9), combined with climate data, using a machine learning-based species distribution model. This approach aimed to identify environmentally suitable habitats for V. paradoxa and locate areas likely to contain healthy and viable seed sources. These areas were identified through the spatial combination of thresholded habitat suitability maps and vegetation indices - an approach herein referred to as the seed zone priority location index (SZPI). The SZPI is an area that is not only climatically suitable for V. paradoxa distribution and survival but also where healthy and viable tree populations can be found. The SZPI is expected to provide vital information necessary to guide the location and collection of suitable and viable seeds required for the restoration and conservation of V. paradoxa.

Keywords

Conservation / Tree species / Seed zones / Vegetation index

Funding

This work was funded by the Nigerian Federal Government TETFUND (Grant ID: KWASU I B R/C RlT/270921 t/0 L 1 ff ETF2020/00 09).

Conflict of interest

The authors declare no conflict of interest in any form.

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