A survey was conducted between October 2010 and June 2011 to determine the diversity, distribution, and abundance of plants in 4 sites of the Lebialem highlands and to relate species diversity and abundance to altitude and soil types. Twelve (12) plots, each of 1 ha (250?×?40?m), were surveyed at the submontane and montane altitudes of the sites. One hundred (100) species belonging to 82 genera were identified with the genera Cola and Psychotria being the most represented. Vulnerable species included Guarea thompsonii, Schefflera hierniana, Allanblackia gabonensis, Cyclomorpha solmsii, Vepris trifoliolata, and Xylopia africana. Species such as Xymalos monospora, Tricalysia atherura, and Piptostigma oyemense present in the study area were endemic to Cameroon. Diversity and distribution of plants were affected by parameters such as the altitude and the soil type. Soil analysis revealed that diversity in the study area was affected by the organic carbon, nitrogen, calcium, and the cation exchange capacity of the soil. 1. Introduction Biodiversity is the degree of variation of life forms within a given ecosystem, biome, or entire planet [1]. It encompasses all species of plants, animals and microorganisms, the ecosystem, and ecological processes of which they are parts. It is an umbrella term for the degree of nature’s variety, including both number and frequency of ecosystems, species, or genes in a given assemblage. Wilson [2] defines biodiversity as the variety of organisms considered at all levels from genetic variants belonging to the same species through arrays of species to arrays of genera, families, and still higher taxonomic levels. Besides South Africa, Cameroon is the most biologically rich country known to date on the African continent [3]. It encompasses an intricate mosaic of diverse habitats with moist tropical forest dominating the south and south-east and covering 54% of the country, mountain forest and savannah in the highlands and sub-Sahelian savannah and near desert in the far north [3]. These diverse habitats harbour more than 9,000 species of plants, 160 species of which are endemic. The majority of the endemic taxa are concentrated around Mount Cameroon and other highland areas. During the last few decades, deforestation of tropical forests areas has accelerated at an alarming rate as extensive areas of forest are being cleared every year [4]. Man affects the forest ecosystem with activities such as agroindustries, shifting cultivation, and hunting. There has been an overwhelming concern about the loss of tropical diversity and an
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