Soils and fire jointly determine vegetation structure in an African savanna

Bibliographische Detailangaben
Veröffentlicht in:	The New phytologist. - 1989. - 216(2017), 4 vom: 25. Dez., Seite 1151-1160
1. Verfasser:	Staver, A Carla (VerfasserIn)
Weitere Verfasser:	Botha, Judith, Hedin, Lars
Format:	Online-Aufsatz
Sprache:	English
Veröffentlicht:	2017
Zugriff auf das übergeordnete Werk:	The New phytologist
Schlagworte:	Journal Article fire grass hydrology landscape rainfall savanna soil texture tree Soil

Beschreibung
Zusammenfassung:	© 2017 The Authors. New Phytologist © 2017 New Phytologist Trust. Savanna vegetation is variable, and predicting how water, nutrients, and chronic disturbances interact to determine vegetation structure in savannas represents a challenge. Here, we examined in situ interactions among rainfall, soils, grasses, fire, and elephants that determine tree layer responses to resource gradients in Kruger National Park in South Africa, using 363 long-term monitoring sites throughout the park. Grass biomass increased with rainfall and on nutrient-rich clay soils. Fire frequency, too, increased with rainfall. Conversely, tree density was greater on sandier soils, where water infiltrates more readily, and in areas where the maximum interval between fires was longer, irrespective of average fire frequency. Elephant density responded positively to tree density, but did not contribute significantly to decreasing tree density. Savanna vegetation structure was reasonably predictable, via a combination of rainfall (favoring grasses), soil (sandy soils favoring trees), and fire (limiting trees until a longer interval between fires allows them to establish). Explicit consideration of bottom-up and top-down interactions may thus contribute to a predictive understanding of savanna vegetation heterogeneity
Beschreibung:	Date Completed 31.07.2018 Date Revised 30.09.2020 published: Print-Electronic Citation Status MEDLINE
ISSN:	1469-8137
DOI:	10.1111/nph.14738