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Landscape Ecology

, Volume 25, Issue 10, pp 1529–1546 | Cite as

Hierarchy and scale: testing the long term role of water, grazing and nitrogen in the savanna landscape of Limpopo National Park (Mozambique)

  • Anneli EkblomEmail author
  • Lindsey Gillson
Research Article

Abstract

This paper compares vegetation dynamics at two sites in the savanna landscape of Limpopo National Park (PNL), Mozambique. In order to test the relationship between vegetation cover and hydrology, nutrient availability and disturbance from grazing and fire over the last 1,200 years at local (100 m2) scales, we use palaeoecological data (i.e. pollen assemblages, charcoal abundance, C/N ratio, stable isotopes and herbivore-associated spore abundance). Two pans governed by similar rainfall regimes (on average 600 mm/year) but different hydrologies are compared. Chixuludzi Pan is responsive to the Limpopo River and is more water rich than Radio Pan, which is situated in a dry landscape with little surface water. The analysis suggests that in savannas where water is scarce, the recruitment of woody taxa is constrained mainly by the availability of underground water. In the Radio Pan sequence, the present grassland savanna has been stable throughout the time studied. In contrast, the Chixuludzi Pan savanna landscape where local hydrology, due to the proximity of Limpopo River, allows for a higher water availability the relationship between grass-arboreal pollen suggests a greater variability in vegetation cover, and other factors such as grazing, herbivory and nitrogen availability are important as controlling mechanisms for woody cover. The historical depth of the analysis enables a sub-hierarchy of local scale process to be identified, in this case local hydrology. Local water availability is shown to override the effect of regional rainfall and, in turn, to control the influence of other local scale factors such as nutrients and grazing.

Keywords

Hierarchical patch dynamics Savanna ecology Pollen Coprophilous spores Nitrogen Fire 

Notes

Acknowledgements

The work was sponsored by the Andrew W. Mellon foundation. The management of Limpopo National Park aided with logistics in the Limpopo Park, particularly William Swanepoel and our field guide Guillermo Maleluke, whose botanical and ecological knowledge has been important in shaping the understanding of the PNL landscape. Peace Parks Foundation has kindly provided GIS coverage for PNL. An acknowledgement goes also to Dr Michel Notelid who assisted during the 2006 fieldwork. We are also grateful to Kathy Willis and the researchers and students at Long-Term Ecology Laboratory, University of Oxford, for laboratory facilities and stimulating debate.

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Copyright information

© Springer Science+Business Media B.V. 2010

Authors and Affiliations

  1. 1.African and Comparative Archaeology, Department of Archaeology and Ancient HistoryUppsala UniversityUppsalaSweden
  2. 2.Plant Conservation Unit, Botany DepartmentUniversity of Cape TownRondeboschSouth Africa

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