Plant Ecology

, Volume 197, Issue 1, pp 17–29 | Cite as

Introduced plants on Kilimanjaro: tourism and its impact

  • Andreas HempEmail author


Kilimanjaro, a world heritage site and an icon of global change, not only suffers from climatic alterations but also is undergoing a drastic socio-economic upheaval. A strong increase of tourism enhances the risk of introducing alien plant species in particular in the upper zones of Kilimanjaro. One such species is Poa annua L., a cosmopolitan weed of European origin on roadsides and pastures. The aim of this study is to document its distribution, the speed of its propagation and risks for the indigenous vegetation of Kilimanjaro, and to compare the findings with other introduced species on this mountain. Based on a complete survey of the vegetation of Kilimanjaro with about 1,500 vegetation plots, plant communities invaded by Poa annua are determined. As with most of the other neophytes on Kilimanjaro, Poa annua invades only anthropogenic vegetation but not undisturbed natural vegetation. Similar to the situation in middle Europe, this neophyte is on Kilimanjaro a constituent of the vegetation of trampled ground, occurring between about 1,600 and 4,000 m asl along climbing routes or their vicinity. On a newly opened climbing route a rapid invasion (5.6 km in 3 months) was observed, which makes it likely that Poa annua spread on Kilimanjaro during the last 30 years in parallel to the increase of the climbing tourism. Although Poa annua is still in the stage of propagation, an invasion of natural vegetation types seems to be unlikely.


Adiantum raddianum Global change Kilimanjaro National Park Neophytes Poa annua L. (Ruderal) vegetation of trampled ground 



I gratefully acknowledge grants by the Deutsche Forschungsgemeinschaft and the Tanzanian Commission for Science and Technology for permitting research. For support in getting permits I owe gratitude to the Chief Park Wardens of Kilimanjaro National Park, Mr. Lomi Ole Moirana and Mr. Nyamakumbati Mafuru, to the Catchment Forest officers and to my counterpart Mr. Jacob Mushi (Tanzania Association of Foresters), Moshi. I further thank the keepers of the East African Herbarium, Nairobi (Kenya) Dr. Siro Masinde and Kew Herbarium, England, Prof. Dr. Owens for permission to study their collections, Quentin Luke and Simon Mathenge (both Nairobi) and Dr. Bernard Verdcourt (Kew) for help in identifying difficult species, Prof. Dr. Len Newton and Peter Paterson (both Nairobi) for improving the English and Prof. Dr. Inge Lenski, Marburg (Germany) for valuable comments on the manuscript.


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Copyright information

© Springer Science+Business Media B.V. 2007

Authors and Affiliations

  1. 1.Ecological Botanical GardenUniversität BayreuthBayreuthGermany

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