Hostname: page-component-cd9895bd7-p9bg8 Total loading time: 0 Render date: 2024-12-27T10:57:36.751Z Has data issue: false hasContentIssue false
  • English
  • Français

Effect of local topographic heterogeneity on tree species assembly in an Acacia-dominated African savanna

Published online by Cambridge University Press:  11 March 2019

Paul Musili Mutuku  and
David Kenfack Open the ORCID record for David Kenfack [Opens in a new window]
Paul Musili Mutuku
Affiliation:
East African Herbarium, Botany Department, National Museums of Kenya, P.O. Box 40658 – 00100 GPO, Museum Hill Road, Nairobi, Kenya
David Kenfack*
Affiliation:
ForestGEO, Smithsonian Tropical Research Institute, P.O. Box 37012, Washington, DC 20013-7012, USA
*
*Email: kenfackd@si.edu
Get access Rights & Permissions [Opens in a new window]

Abstract

Stand structure and tree species diversity patterns were examined plot-wide and among four topographically defined habitats (plateau, cliff, low plain and depressions) in a 120-ha permanent plot in an Acacia-dominated savanna in Mpala Ranch, central Kenya. The four habitats were defined by clustering the 3000 quadrats of 20 × 20 m in the plot based on their altitude, slope and convexity. Structural and floristic differences among the four habitats were examined and species-habitat associations were tested for the 30 most abundant species using torus translation randomization tests. The plot included 113 337 trees in 62 species with diameter at knee height ≥ 2 cm (18.4 species ha−1), 41 genera and 23 families. Fabaceae with the genus Acacia were the dominant family, followed by Euphorbiaceae and Ebenaceae. Tree density and basal area were twice as high on low plain and depressions than on the plateau. Species richness was highest in the cliff and was seven times higher than in the adjacent plateau. Half of the species assessed showed significant positive associations with one habitat and 21 showed significant negative associations with at least one habitat. The variation in stand structure and tree species diversity within the Mpala plot shows that topography is among the important drivers of local species distribution and hence the maintenance of tree diversity in savannas.

Keywords

East AfricaForestGEOKenyaLaikipiasavannaspecies-habitat associationspecies richnesstopographic habitattree diversity
Type
Research Article
Information
Journal of Tropical Ecology , Volume 35 , Issue 2 , March 2019 , pp. 46 - 56
Copyright
© Cambridge University Press 2019 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Literature cited

Andersen, KM, Turner, BL and Dalling, JW (2010) Soil-based habitat partitioning in understorey palms in lower montane tropical forests. Journal of Biogeography 37, 278–292.CrossRefGoogle Scholar
Anderson-Teixeira, KJ, Davies, SJ, Bennett, AC, Gonzalez-Akre, EB, Muller-Landau, HC, Joseph Wright, S, et al. (2015) CTFS-ForestGEO: a worldwide network monitoring forests in an era of global change. Global Change Biology 21, 528–549.CrossRefGoogle Scholar
Asner, GP, Levick, SR, Kennedy-Bowdoin, T, Knapp, DE, Emerson, R, Jacobson, J, Colgan, MS and Martin, RE (2009) Large-scale impacts of herbivores on the structural diversity of African savannas. Proceedings of the National Academy of Sciences USA 106, 4947–4952.CrossRefGoogle ScholarPubMed
Augustine, DJ and McNaughton, SJ (2004) Regulation of shrub dynamics by native browsing ungulates on East African rangeland. Journal of Applied Ecology 41, 45–58.CrossRefGoogle Scholar
Beentje, H, Adamson, J and Bhanderi, D (1994) Kenya Trees, Shrubs, and Lianas. Nairobi: National Museums of Kenya, 762 pp.Google Scholar
Belsky, AJ (1984) Role of small browsing mammals in preventing woodland regeneration in the Serengeti National Park, Tanzania. African Journal of Ecology 22, 271–279.CrossRefGoogle Scholar
Caylor, KK, Gitonga, J and Martins, DJ (2017) Mpala Research Centre Meteorological and Hydrological Dataset. Laikipia: Mpala Research Centre.Google Scholar
Chuyong, GB, Kenfack, D, Harms, KE, Thomas, DW, Condit, R and Comita, LS (2011) Habitat specificity and diversity of tree species in an African wet tropical forest. Plant Ecology 212, 1363–1374.CrossRefGoogle Scholar
Condit, R (1998) Tropical Forest Census Plots: Methods and Results from Barro Colorado Island, Panama and a Comparison with other Plots. New York, NY: Springer Science & Business Media, 216 pp.CrossRefGoogle Scholar
Condit, R, Lao, S, Singh, A, Esufali, S and Dolins, S (2014) Data and database standards for permanent forest plots in a global network. Forest Ecology and Management 316, 21–31.CrossRefGoogle Scholar
Coughenour, MB and Ellis, JE (1993) Landscape and climatic control of woody vegetation in a dry tropical ecosystem: Turkana District, Kenya. Journal of Biogeography 20, 383–398.CrossRefGoogle Scholar
Cox, GW and Gakahu, CG (1985) Mima mound microtopography and vegetation pattern in Kenyan savannas. Journal of Tropical Ecology 1, 23–36.CrossRefGoogle Scholar
Cumming, DH, Fenton, MB, Rautenbach, IL, Taylor, RD, Cumming, GS, Cumming, MS, Dunlop, JM, Ford, AG, Hovorka, MD and Johnston, DS (1997) Elephants, woodlands and biodiversity in southern Africa. South African Journal of Science 93, 231–236.Google Scholar
Edwards, DC (1940) A vegetation map of Kenya with particular reference to grassland types. Journal of Ecology 28, 377–385.CrossRefGoogle Scholar
Frost, PGH and Robertson, F (1985) Fire: the ecological effects of fire in savannas. In Walker, TS and Walker, BH (eds), Determinants of Tropical Savannas. Oxford: IRL Press, pp. 93–140.Google Scholar
Georgiadis, NJ, Olwero, JGN, Ojwang’, G and Romañach, SS (2007) Savanna herbivore dynamics in a livestock-dominated landscape: I. Dependence on land use, rainfall, density, and time. Biological Conservation 137, 461–472.CrossRefGoogle Scholar
Goheen, JR and Palmer, TM (2010) Defensive plant-ants stabilize megaherbivore-driven landscape change in an african savanna. Current Biology 20, 1768–1772.CrossRefGoogle Scholar
Gunatilleke, CVS, Gunatilleke, IAUN, Esufali, S, Harms, KE, Ashton, PMS, Burslem, DFRP and Ashton, PS (2006) Species–habitat associations in a Sri Lankan dipterocarp forest. Journal of Tropical Ecology 22, 371–384.CrossRefGoogle Scholar
Harms, KE, Condit, R, Hubbell, SP and Foster, RB (2001) Habitat associations of trees and shrubs in a 50-ha neotropical forest plot. Journal of Ecology 89, 947–959.CrossRefGoogle Scholar
Kimuyu, DM, Sensenig, RL, Riginos, C, Veblen, KE and Young, TP (2014) Native and domestic browsers and grazers reduce fuels, fire temperatures, and acacia ant mortality in an African savanna. Ecological Applications 24, 741–749.CrossRefGoogle Scholar
Kinnaird, MF and O’Brien, TG (2012) Effects of private-land use, livestock management, and human tolerance on diversity, distribution, and abundance of large African mammals. Conservation Biology 26, 1026–1039.CrossRefGoogle ScholarPubMed
Kyalangalilwa, B, Boatwright, JS, Daru, BH, Maurin, O and Van Der Bank, M (2013) Phylogenetic position and revised classification of Acacia s.l. (Fabaceae: Mimosoideae) in Africa, including new combinations in Vachellia and Senegalia. Botanical Journal of the Linnean Society 172, 500–523.CrossRefGoogle Scholar
Lai, J, Mi, X, Ren, H and Ma, K (2009) Species-habitat associations change in a subtropical forest of China. Journal of Vegetation Science 20, 415–423.CrossRefGoogle Scholar
Langevelde, FV, Van Der Vijver, CADM, Kumar, L, Van Der Koppel, J, Ridder, ND, Andel, JV, Skidmore, AK, Hearne, JW, Stroosnijder, L, Bond, WJ, Prins, HHT and Rietkerk, M (2003) Effects of fire and herbivory on the stability of savanna ecosystems. Ecology 84, 337–350.CrossRefGoogle Scholar
Madden, D and Young, TP (1992) Symbiotic ants as an alternative defense against giraffe herbivory in spinescent Acacia drepanolobium. Oecologia 91, 235–238.CrossRefGoogle ScholarPubMed
Moe, SR, Mobæk, R and Narmo, AK (2009) Mound building termites contribute to savanna vegetation heterogeneity. Plant Ecology 202, 31.CrossRefGoogle Scholar
Moeslund, JE, Arge, L, Bøcher, PK, Dalgaard, T and Svenning, J-C (2013) Topography as a driver of local terrestrial vascular plant diversity patterns. Nordic Journal of Botany 31, 129–144.CrossRefGoogle Scholar
Morrison, DA, Cary, GJ, Pengelly, SM, Ross, DG, Mullins, BJ, Thomas, CR and Anderson, TS (1995) Effects of fire frequency on plant species composition of sandstone communities in the Sydney region: inter-fire interval and time-since-fire. Australian Journal of Ecology 20, 239–247.CrossRefGoogle Scholar
Palmer, TM, Doak, DF, Stanton, ML, Bronstein, JL, Kiers, ET, Young, TP, Goheen, JR and Pringle, RM (2010) Synergy of multiple partners, including freeloaders, increases host fitness in a multispecies mutualism. Proceedings of the National Academy of Sciences USA 107, 17234–17239.CrossRefGoogle Scholar
Paoli, GD, Curran, LM and Zak, DR (2006) Soil nutrients and beta diversity in the Bornean Dipterocarpaceae: evidence for niche partitioning by tropical rain forest trees. Journal of Ecology 94, 157–170.CrossRefGoogle Scholar
Pei, N, Lian, J-Y, Erickson, DL, Swenson, NG, Kress, WJ, Ye, W-H and Ge, X-J (2011) Exploring tree-habitat associations in a Chinese subtropical forest plot using a molecular phylogeny generated from DNA barcode loci. PLoS ONE 6, e21273.CrossRefGoogle Scholar
Pringle, RM, Prior, KM, Palmer, TM, Young, TP and Goheen, JR (2016) Large herbivores promote habitat specialization and beta diversity of African savanna trees. Ecology 97, 2640–2657.CrossRefGoogle ScholarPubMed
Roques, KG, O’Connor, TG and Watkinson, AR (2001) Dynamics of shrub encroachment in an African savanna: relative influences of fire, herbivory, rainfall and density dependence. Journal of Applied Ecology 38, 268–280.CrossRefGoogle Scholar
Russo, SE, Davies, SJ, King, DA and Tan, S (2005) Soil-related performance variation and distributions of tree species in a Bornean rain forest. Journal of Ecology 93, 879–889.CrossRefGoogle Scholar
Sankaran, M, Hanan, NP, Scholes, RJ, Ratnam, J, Augustine, DJ, Cade, BS, et al. (2005). Determinants of woody cover in African savannas. Nature 438, 846–849.CrossRefGoogle ScholarPubMed
Sankaran, M, Ratnam, J and Hanan, NP (2004) Tree-grass coexistence in savannas revisited – insights from an examination of assumptions and mechanisms invoked in existing models. Ecology Letters 7, 480–490.CrossRefGoogle Scholar
Trapnell, CG (1959) Ecological results of woodland and burning experiments in Northern Rhodesia. Journal of Ecology 47, 129–168.CrossRefGoogle Scholar
Valencia, R, Foster, RB, Villa, G, Condit, R, Svenning, J-C, Hernández, C, Romoleroux, K, Losos, E, Magård, E and Balslev, H (2004) Tree species distributions and local habitat variation in the Amazon: large forest plot in eastern Ecuador. Journal of Ecology 92, 214–229.CrossRefGoogle Scholar
Ward, JH (1963) Hierarchical grouping to optimize an objective function. Journal of the American Statistical Association 58, 236–244.CrossRefGoogle Scholar
Williams, RJ, Duff, GA, Bowman, DMJS and Cook, GD (1996) Variation in the composition and structure of tropical savannas as a function of rainfall and soil texture along a large-scale climatic gradient in the Northern Territory, Australia. Journal of Biogeography 23, 747–756.CrossRefGoogle Scholar
Wu, XB and Archer, SR (2005) Scale-dependent influence of topography-based hydrologic features on patterns of woody plant encroachment in savanna landscapes. Landscape Ecology 20, 733–742.CrossRefGoogle Scholar
Yamakura, T, Kanzaki, M, Itoh, A, Ohkubo, T, Ogino, K, Chai, EOK, Lee, HS and Ashton, PS (1995) Topography of a large-scale research plot established within the Lambir rain forest in Sarawak. Tropics 5, 41–56.CrossRefGoogle Scholar
Young, TP, Okello, BD, Kinyua, D and Palmer, TM (1997) KLEE: a long-term multi-species herbivore exclusion experiment in Laikipia, Kenya. African Journal of Range and Forage Science 14, 94–102.CrossRefGoogle Scholar
Young, TP, Porensky, LM, Riginos, C, Veblen, KE, Odadi, WO, Kimuyu, DM, Charles, GK and Young, HS (2018) Relationships between cattle and biodiversity in multiuse landscape revealed by Kenya Long-Term Exclosure Experiment. Rangeland Ecology and Management 71, 281–291.CrossRefGoogle Scholar