Urban green area provides refuge for native small mammal biodiversity in a rapidly expanding city in Ghana

Abstract

Urbanization is a key driver of global biodiversity loss. Although sub-Saharan African countries are experiencing unprecedented urbanization and urban expansion, very little is known about how this impacts tropical biodiversity. Here, we assessed the effects of urban expansion and urban green space on local small mammal species diversity in Accra, Ghana. We surveyed small mammals in the University of Ghana botanical garden, an urban green area (UGA) and adjoining built-up environment (BE) and compared the results with baseline data (BLD) collected when large areas of the current city still remained mostly undeveloped. The methodology involved live-trapping using Sherman collapsible live-traps. Our data showed higher small mammal abundance and diversity in the UGA than BE. Similarity of species composition was higher between UGA and BLD than between BE and BLD. The small mammal species captured in BE (the rodents Mastomys erythroleucus, Rattus rattus, and Arvicanthis rufinus, and the shrew Crocidura olivieri) are known to easily adapt to human-modified landscapes. Our results suggest that urbanization negatively influenced the abundance, diversity, and community composition of small mammals. Efforts should be directed towards the integration of urban green areas into urban land development planning in developing countries in order to conserve local wildlife and ecological services that enhance the quality of urban life.

The impact of urban tree cover on perceived safety

“…From an ecosystem services approach, the study's outcomes support the view that trees can be an important ecosystem service provider in urban areas. In addition to ecosystem services such as capturing air and water pollutants, providing shade and habitat, and decreasing CO2 emissions (Hirokawa et al, 2011;Niemelä et al, 2010;Nowak et al, 2006;Ofori et al, 2018;Soares et al, 2011), urban trees may provide another ecosystem service: improving perceptions of neighborhood safety.…”

“…Specifically, urban trees contribute to countering the effects of climate change by decreasing atmospheric carbon dioxide (CO2) through the processes of carbon storage and sequestration (Liu & Li, 2012;Nowak et al, 2013). Trees also increase biodiversity by providing shelter for various species (Ofori et al, 2018), improve air quality in cities (Nowak et al, 2006), improve resilience to flooding by providing storm water attenuation (Roy et al, 2012), and help reduce energy demands (Roy et al, 2012;Soares et al, 2011). These environmental benefits as well as the aesthetic, amenity, and shading benefits of urban trees generate economic benefits that usually outweigh relevant costs (Soares et al, 2011;Song et al, 2018).…”

Air Quality in Africa: Public Health Implications

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Air Pollution and Urban Green Space: Evidence of Environmental Injustice in Adama, Ethiopia

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