We used the broad elevational gradient of Kilimanjaro ranging from warm tropical lowland to cold Afro-alpine temperature regimes and the occurrence of natural, nearly untouched as well as of anthropogenic and heavily disturbed habitats to study how elevation and disturbance by humans affect the proportion of useful plant species in different habitat types. Of the 962 vascular plant species recorded in our 60 study plots, 563 species turned out to be listed as useful in the literature. We classified these species into six usage categories. With linear models we tested for relationships between the proportion of useful species per plot and elevation for natural habitats, and with analysis of variance we compared the proportion of useful species between plots in disturbed and natural habitats at similar elevation. The proportion of useful species for all usage categories increased from 860 to 2500 m asl and decreased with higher elevation. We also found an overall positive correlation between the number of useful plants and the species richness of our plots. Human-influenced habitats had higher proportions of useful species for all usage categories, except for construction and fuel wood usage which were higher in natural savanna and lower montane forest than in used habitats at these elevations. Given the high proportions of useful species, we conclude that preserving the biodiversity of Kilimanjaro ecosystems is indispensable for maintaining the diversity of useful plants species for the local people who rely on it for food, sustainable access to medicinal, fuel, construction and forage material.

中文翻译：

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与坦桑尼亚乞力马扎罗山海拔和土地利用有关的可用野生植物物种

我们使用了乞力马扎罗山的广泛海拔梯度，范围从温暖的热带低地到寒冷的非洲高山温度模式，以及自然，几乎未曾接触以及人为和严重干扰的栖息地的发生，研究了人类的海拔和干扰如何影响有用的比例不同生境类型的植物物种。在我们的60个研究样地中记录的962种维管植物物种中，有563种被证明在文献中有用。我们将这些物种分为六个使用类别。通过线性模型，我们测试了每个样地中有用物种的比例与自然栖息地海拔之间的关系，并且通过方差分析，我们比较了海拔相似且受干扰的自然栖息地中样地之间有用物种的比例。所有用途类别中有用物种的比例从860升至2500 m asl，并随着海拔的升高而降低。我们还发现有用植物的数量与地块物种丰富度之间总体呈正相关。受人类影响的栖息地在所有用途类别中都有较高的有用物种比例，但天然大草原和山地森林中的建筑和薪柴使用量高于这些海拔的人工栖息地。鉴于有用物种的比例很高，我们得出结论，对于乞力马扎罗山生态系统而言，保持其有用植物物种的多样性对于维护依靠它来获取食物，可持续获取药物，燃料，建筑和饲料材料的当地人民来说是必不可少的。