caa a22 4500 445384042 CHVBK 20180317143026.0 cr unu---uuuuu 170323e20111201xx s 000 0 eng 10.1007/s10021-011-9485-z doi (NATIONALLICENCE)springer-10.1007/s10021-011-9485-z Relative Impacts of Elephant and Fire on Large Trees in a Savanna Ecosystem [Elektronische Daten] [Graeme Shannon, Maria Thaker, Abi Vanak, Bruce Page, Rina Grant, Rob Slotow] Elephant and fire are considered to be among the most important agents that can modify the African savanna ecosystem. Although the synergistic relationship between these two key ecological drivers is well documented, it has proved much more difficult to establish the relative effects they have on savanna vegetation structure at a fine-scale over time. In this study, we explore the comparative impacts of fire and elephant on 2,522 individually identified large trees (≥5m in height) in the Kruger National Park, South Africa. Data were collected from 21 transects first surveyed in April 2006 and resurveyed in November 2008, to determine the relative importance of past damage by these agents on subsequent impacts and mortality. The occurrence of fire or elephant damage in 2006 affected the amount of tree volume subsequently removed by both these agents; elephant removed more tree volume from previously burned trees and the impact of subsequent fire was higher on previously burned or elephant-utilized trees than on undamaged trees. Mortality was also affected by an interaction between previous and recent damage, as the probability of mortality was highest for trees that suffered from fire or elephant utilization after being pushed over. Subsequent fire damage, but not elephant utilization, on debarked trees also increased the probability of mortality. Mortality was twice (4.6% per annum) that of trees progressing into the ≥5m height class, suggesting an overall decline in large tree density during the 30-month study period. The responses of large trees were species and landscape-specific in terms of sensitivity to elephant and fire impacts, as well as for levels of mortality and progression into the ≥5m height class. These results emphasize the need for fine-scale site-specific knowledge for effective landscape level understanding of savanna dynamics. Springer Science+Business Media, LLC, 2011 vegetation dynamics nationallicence ecological drivers nationallicence woody species nationallicence savanna management nationallicence tree survival nationallicence elephant nationallicence fire nationallicence herbivory nationallicence Shannon Graeme Amarula Elephant Research Programme, School of Biological and Conservation Sciences, University of KwaZulu-Natal, Westville Campus, Pvt. Bag 54001, 4000, Durban, South Africa aut Thaker Maria Amarula Elephant Research Programme, School of Biological and Conservation Sciences, University of KwaZulu-Natal, Westville Campus, Pvt. Bag 54001, 4000, Durban, South Africa aut Vanak Abi Amarula Elephant Research Programme, School of Biological and Conservation Sciences, University of KwaZulu-Natal, Westville Campus, Pvt. Bag 54001, 4000, Durban, South Africa aut Page Bruce Amarula Elephant Research Programme, School of Biological and Conservation Sciences, University of KwaZulu-Natal, Westville Campus, Pvt. Bag 54001, 4000, Durban, South Africa aut Grant Rina Scientific Services, Kruger National Park, Box 106, 1350, Skukuza, South Africa aut Slotow Rob Amarula Elephant Research Programme, School of Biological and Conservation Sciences, University of KwaZulu-Natal, Westville Campus, Pvt. Bag 54001, 4000, Durban, South Africa aut Ecosystems Springer-Verlag 14/8(2011-12-01), 1372-1381 1432-9840 14:8<1372 2011 14 10021 https://doi.org/10.1007/s10021-011-9485-z text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10021-011-9485-z text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Shannon Graeme Amarula Elephant Research Programme, School of Biological and Conservation Sciences, University of KwaZulu-Natal, Westville Campus, Pvt. Bag 54001, 4000, Durban, South Africa aut NATIONALLICENCE 700 1- Thaker Maria Amarula Elephant Research Programme, School of Biological and Conservation Sciences, University of KwaZulu-Natal, Westville Campus, Pvt. Bag 54001, 4000, Durban, South Africa aut NATIONALLICENCE 700 1- Vanak Abi Amarula Elephant Research Programme, School of Biological and Conservation Sciences, University of KwaZulu-Natal, Westville Campus, Pvt. Bag 54001, 4000, Durban, South Africa aut NATIONALLICENCE 700 1- Page Bruce Amarula Elephant Research Programme, School of Biological and Conservation Sciences, University of KwaZulu-Natal, Westville Campus, Pvt. Bag 54001, 4000, Durban, South Africa aut NATIONALLICENCE 700 1- Grant Rina Scientific Services, Kruger National Park, Box 106, 1350, Skukuza, South Africa aut NATIONALLICENCE 700 1- Slotow Rob Amarula Elephant Research Programme, School of Biological and Conservation Sciences, University of KwaZulu-Natal, Westville Campus, Pvt. Bag 54001, 4000, Durban, South Africa aut NATIONALLICENCE 773 0- Ecosystems Springer-Verlag 14/8(2011-12-01), 1372-1381 1432-9840 14:8<1372 2011 14 10021 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer