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bioRxiv · 10.1101/2021.01.28.428667

The effects of hydroelectric dam construction on spatial-temporal changes of land use land cover in Bui National Park, Ghana

Bempah, G.·Boama, P.·Lu, C.
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Abstract

The construction of hydroelectric dams in forest reserves has become a matter of concern for biodiversity conservationists. Visibly among which is the potential to cause changes in climate and land cover and subsequently affect fauna and flora composition. Spatio-temporal changes of climate and land cover in the Bui National Park was analyzed using indices calculations of the landscape based on land cover maps obtained from Landsat satellite images for pre-and post-dam construction periods. Significant changes in land cover following the dam construction were observed. Notable changes include the built-up areas and water body, which recorded an increase of 315.64 % and 4593.43 % respectively, while the forest area decreased. Significant reduction in rainfall (U = 24,{rho} < 0.05) and increase in temperature (U = 22.5,{rho} < 0.05) were observed between the pre-and post-dam construction periods. Increased human activities such as illegal mining, indiscriminate tree felling, uncontrolled cattle grazing and charcoal production within the reserve results from inadequate monitoring and law enforcement after the dam construction could likely compound the changes in land cover.

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Bempah, G., Boama, P., Lu, C.. 2021-01-30. The effects of hydroelectric dam construction on spatial-temporal changes of land use land cover in Bui National Park, Ghana. https://doi.org/10.1101/2021.01.28.428667

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