Conservation Threats to Indigenous Trees: Urban Highway Forest Composition and Diversity in Ghana’s Central Region

다국어 초록 (Multilingual Abstract)

Roadside trees provide critical ecosystem services, including amenity and life support benefits. However, the biodiversity status of many urban roadside trees is unknown to support meaningful planning and implementation of sustainable urban cities. To address this, 304 street trees were enumerated and identified from all 5 highways in the Central region of Ghana to determine their composition, abundance, and diversity. The standard line transect sampling technique was used. Twenty-one species, 20 genera, and 8 families were identified, with Senna siamia (25.3 %) being the most prevalent species. Based on the origin of the 21 tree species, 86% were exotic and 14% were indigenous. The top five most abundant tree species were Senna siamea, Azadirachta indica, Khaya senegalensis, Albizia lebbeck, and Eucalyptus deglupta, accounting for 83.56% of the individual trees. The family Fabaceae was the most dominant, having 47.62% of tree species. The R2 statistic demonstrated that only 56.07% of the variance of the tree species family was explained by the variance of the species density. A low Simpson’s inverse index (SDI) of 5.91 was recorded. More native trees such as Khaya senegalensis, Acacia auriculiformis, and Parkia speciosa and a wider variety of species should be planted and re-planted along the roadways in the region.