Effect of the Seasonal Burning on Tree Species in the Guinea Savanna Woodland, Ghana: Implications for Climate Change Mitigation

Abstract

The indiscriminate burning of vegetation is a common practice in the Guinea savanna of Ghana. Burning begins at the onset of the dry season (November) and lasts until the end (April). This study investigated the effects of time of burning on tree diversity and density in the Mole National Park, Ghana. A total of 36 (10 m x 10 m) quadrats were randomly demarcated in three treatments of early and late dry season burning and non-burning study plots. Samples were taken in March, a few weeks after the late burning period. Twenty seven different species belonging to fourteen families were recorded in all the treatments. Most of the species identified belonged to the families Combretaceae, Fabaceae and Leguminoceae. Vitellaria paradoxa, Terminalia avicennioides, Combretum adenogonium and Combretum molle were the most common and abundant in all treatments. Late burning plots recorded the lowest diversity amongst the three treatments. Non-burning plots had higher tree density than burnt plots. Early burning treatment recorded more diverse individual species but had the lowest density. Higher tree densities would enhance carbon sequestration. However, ecosystem resilience is also dependent on the diversity of biotic communities among other factors. Sustainable land use practices including protections of trees on farms and prescribed early dry season burns could be an option to contribute to the mitigation of climate change in the region. Late dry season fires are a threat to tree species populations and should be discouraged.

Land Cover Changes in Ghana over the Past 24 Years

“…The effects of wildfires, farming activities, and fuelwood extractions are likely exacerbated by the vulnerability of savannah areas, which are predominant in the northern parts of Ghana to climate change and variability as well as extreme climate events including erratic rainfall patterns, dry spells, and high temperatures [74][75][76]. Amoako et al [77] reported that fire, which is a very common tool used to burn bush to stimulate growth of fresh forage for livestock, land clearing, wild honey hunting, and for game hunting activities in the savannah areas of Ghana, has negative consequences on vegetation. They also determined that burning has a negative effect on tree density when they investigated the impacts of seasonal burning on tree species in the Guinea Savannah Woodland in the Mole National Park.…”

Fire use practices, knowledge and perceptions in a West African savanna parkland

“…Due to its proximity to the Sahel, the region experiences dry, dusty north-easterly winds (Harmattan) between November and April, which facilitates the annual vegetation burning [ 52 ] across all the districts in the region. The area is characterised by large areas of natural pastures with grass species from the sub-families of Andropogoneae and Paniceae [ 53 , 54 ], interspersed with fire and drought-resistant woody species from the families Fabaceae and Combretaceae [ 35 , 55 ].…”

Response of Peanut Varieties to Phosphorus and Rhizobium Inoculant Rates on Haplic Lixisols of Guinea Savanna Zone of Ghana

“…The vegetation is basically Guinea savanna which is interspersed with trees and grassland that are drought resistant. Bush fire is an annual event, which usually destroys the vegetation (Amoako et al, 2018). The fires are noted to result in substantial losses of plant nutrients, which has a negative impact on the livelihood of the people.…”