Abstract
Most studies undertaken in the field of agroforestry have focussed on system design, soil fertility management, and system interactions. Less emphasis has been placed on biodiversity aspects. The aim of this study is to investigate the potential of indigenous, multistrata agroforests for maintaining native woody species diversity in the south-eastern Rift Valley escarpment, Ethiopia. A total of 60 farms, representing three agroforest types (enset-AF, enset-coffee-AF and fruit-coffee-AF), were randomly selected along altitudinal gradients. Enset (Ensete ventricosum) is a perennial, herbaceous monocarpic banana-like plant which serves as a food plant in Ethiopia. The three agroforests are results of the domestication of natural forests and intensification of the landuse systems centuries ago. Sample-based assessment protocols were employed to place sample quadrats and to measure all individuals in the quadrats. A total of 58 woody species, belonging to 49 genera and 30 families, was recorded. Of all woody species identified, 86% were native. The highest proportion of native woody species was recorded in enset-AF (92%), followed by enset-coffee-AF (89%) and fruit-coffee-AF (82%). Among native tree species, Millettia ferruginea and Cordia africana were the most widespread. In all, 22 native woody species were recorded as of interest for conservation, acccording to IUCN Red lists and local criteria. Among them, Pygeum africanum and Rhus glutinosa were categorised as vulnerable in the wild, and in need of conservation priority. The introduction of non-native fruit trees in agroforests can be a threat to maintenance of native woody species. Management strategies favoring enset and coffee will also put other native tree species at risk. A smaller number of native woody species was recorded in fruit-coffee-AF, but a higher mean basal area and stem number. The mean basal area and stem number ranged from 5.4 ± 0.5 to 11.7 ± 1.0 m2 ha−1 and 625 ± 84 to 1,505 ± 142 stems ha−1, respectively. Altitude explained 68 and 71% of the variation in species richness and abundance, respectively. Finally, it is concluded that recognition of the indigenous agroforestry system as an option for maintaining native woody species should be given more attention, to counteract the local threat of these species from the wild.
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References
Abebe T (2005) Diversity in homegarden agroforestry system of southern Ethiopia. Dissertation, Wageningen Agricultural University
Abebe T, Wiersum KF, Bongers F (2010) Spatial and temporal variation in crop diversity in agroforestry homegardens of southern Ethiopia. Agrofor Syst 78:309–322. doi:10.1007/s10457-009-9246-6
Acharya KP (2006) Linking trees on farms with biodiversity conservation in subsistence farming in Nepal. Biodivers Conserv 15:631–646. doi:10.1007/s10531-005-2091-7
Aerts R, Van Overtveld K, Haile M, Hermy M, Deckers J, Muys B (2006) Species composition and diversity of small Afromontane forest fragments in north Ethiopia. Plant Ecol 187:127–142. doi:10.1007/s11258-006-9137-0
Asase A, Tetteh AD (2010) The role of complex agroforestry systems in the conservation of forest tree diversity and structure in southeastern Ghana. Biodivers Conserv 14:1225–1240
Asfaw Z (2003) Tree species diversity, toposoil conditions and arbuscular mycorrhizal association in the Sidama traditional agroforestry landuse, Southern Ethiopia. Dissertation, Swedish University of Agricultural Sciences
Asfaw Z, Ågren IG (2007) Farmers’ local knowledge and topsoil properties of agroforestry practices in Sidama, Southern Ethiopia. Agrofor Syst 71:35–48. doi:10.1007/s10457-007-9087-0
Asfaw Z, Nigatu A (1995) Home-gardens in Ethiopia: characteristics and plant diversity. SINET 18(2):235–266
Asfaw Z, Woldu Z (1997) Crop association of home-gardens in Welayata and Gurage in southern Ethiopia. SINET 20(1):73–90
Atta-Krah K, Kindt R, Skilton JN, Amaral W (2004) Managing biological and genetic diversity in tropical agroforestry. Agrofor Syst 61:183–194
Backes MM (2001) The role of indigenous trees for conservation of biocultural diversity in traditional agroforestry landuse systems: the Bungoma case study, in situ conservation of indigenous tree species. Agrofor Syst 52:119–132
Bandeira PF, Martorell CJ, Meave A, Caballero J (2005) The role of rustic coffee plantations in the conservation of wild tree diversity in the Chinantec region of Mexico. Biodivers Conserv 14:1225–1240. doi:10.1007/s10531-004-7843-2
Bekele T, Haase G, Soromessa T (1999) Forest genetic resources of Ethiopia: status and proposed actions. In: Edwards S, Demissie A, Bekele T and Haase G (eds) The national forest resources conservations strategy development workshop. Proceedings of national workshop from 21–22, June 1999 held in Addis Ababa. Institute of Biodiversity Conservation and Research (IBCR), GTZ, Addis Ababa, pp 39–48
Bhagwat SA, Willis KJ, Birks HJB, Whittaker RJ (2008) Agroforestry: a refuge for tropical biodiversity? Trends Ecol Evol 23(5):261–265
Boffa MJ, Turyomurugyendo L, Barnekow-Lillesø PJ, Kindt R (2005) Enhancing farm tree diversity as a means of conserving landscape-based biodiversity: insight from the Kigezi highlands Southwestern Uganda. Mt Res Dev 25(3):212–217
Brandt AS (1984) New perspective on the origins of food production in Ethiopia. In: Clark JD and Brandt A (eds) From hunters to farmers: the case and consequence of food production in Africa, University of California Press, Berkeley, pp 173–190
Brandt AS, Spring A, Hiebsch C, McCabe JT, Tabogie E, Diro M, Wolde-Michael G, Yntiso G, Shigeta M, Tesfaye S (1997) The “Tree Against Hunger” Enset-Based Agricultural Systems in Ethiopia. American Association for the Advancement of Science, Washington
Caiafa AN, Martins FR (2010) Forms of rarity of tree species in the southern Brazilian Atlantic rainforest. Biodivers Conserv 19:2597–2618
Cairns MA, Meganck RA (1994) Carbon sequestration, biological diversity, and sustainable development: integrated forest management. Environ Manag 18(1):13–22
Correia M, Diabate M, Beavogu P, Guilavogui K, Lamanda N, de Foresta H (2010) Conserving forest tree diversity in Guine’e Forestie`re (Guinea, West Africa): the role of coffee-based Agroforests. Biodivers Conserv 9:1725–1747. doi:10.1007/s10531-010-9800-6
Das T, Das KA (2005) Inventorying plant biodiversity in homegardens: a case study in Barak valley, Assam, north-east India. Curr Sci 89(1):155–163
Duguma LA, Hager H (2010) Woody plants diversity and possession, and their future prospects in small-scale tree and shrub growing in agricultural landscapes in central highland of Ethiopia. Small Scale For 9:153–174. doi:10.1007/s11842-009-9108-0
Dytham C (2003) Choosing and using statistics: a biologist’s guide. 2nd edition. Blackwell, Oxford
Edmond N, Yakam-Simen F, Tadesse KK, Romeij P (2000) Gedeo Zone Mapping Project. Phase 2. Final Report. Treemail, Heelsum, The Netherlands, Privateers N.V. and the Agricultural Bureau for Gedeo Zone. http://www.treemail.nl/download. Accessed 24 March 2009
Edwards S, Kelbessa E (1999) Forest genetic resources of Ethiopia: status and proposed actions. In: Edwards S, Demissie A, Bekele T and Haase G (eds), The national forest resources conservations strategy development workshop. Proceedings of national workshop from 21–22, June 1999 held in Addis Ababa. Institute of Biodiversity Conservation and Research (IBCR), GTZ, Addis Ababa, pp 101–133
Faria D, Paciencia MLB, Dixo M, Laps RR, Baumgartenzards J (2007) Ferns, frogs, lizards, birds and bats in forest fragments and shade cacao plantations in two contrasting landscapes in the Atlantic forest, Brazil. Biodivers Conserv 16:2335–2357. doi:10.1007/s10531-007-9189-z
Funk J, Kerr S (2007) Restoring forests through carbon farming on Māori land in New Zealand/Aotearoa. Mountain Res Dev 27(3). doi:10.1659/mrd.0921
Gebremariam AH, Bekele M, Ridgewell A (2009) Small and medium forest enterprises in Ethiopia. IIED Small and Medium Forest Enterprise Series No. 26. FARM-Africa and International Institute for Environment and Development, London
Gindaba J, Rozanov A, Negash L (2005) Trees on farms and their contribution to soil fertility parameters in Badessa, Eastern Ethiopia. Biol Fertil Soils 42:66–71
Hailu T, Negash L, Olsson M (2000) Millettia ferruginea from southern Ethiopia: impacts on soil fertility and growth of maize. Agrofor Syst 48:9–24
Harvey CA, Villalobos GJA (2007) Agroforestry systems conserve species-rich but modified assemblage of tropical birds and bats. Biodivers Conserv 16:2257–2292. doi:10.1007/s10531-007-9194-2
Hervé BDB, Vidal S (2008) Plant biodiversity and vegetation structure in traditional cacao forest gardens in southern Cameroon under different management. Biodivers Conserv 17:1821–1835. doi:10.1007/s10531-9276-1
Hoehn P, Steffan-Dewenter I, Tscharntke T (2010) Relative contribution of agroforestry, rainforest and openland to local and regional bee diversity. Biodivers Conserv 19:2189–2200. doi:10.1007/s10531-010-9831-z
Huang H, Luukkanen O, Johanson S, Kaarakka V, Räisänen S, Vihemäki H (2002) Agroforestry for biodiversity conservation of nature reserves: functional group identification and analysis. Agrofor Syst 55:65–72
Kanshie TK (2002) Five thousand years of sustainability? A case study on Gedeo landuse (Southern Ethiopia). Dissertation, Wageningen Agricultural University
Kindt R, Kalinganire A, Larwanou M, Belem M, Dakouo JM, Bayala J, Kaire M (2008) Tree diversity in western Kenya: using profiles to characterize richness and evenness. Biodivers Conserv 15:1253–1270
Kumar BM, Nair PKR (2004) The enigma of tropical homegardens. Agrofor Syst 61:135–152
Magurran AE (2004) Measuring biological diversity. Blackwell Sciences, Oxford
McCune B, Mefford MJ (2006) Multivariate analysis of ecological data. PC-ORD Version 5. MjM software, Gleneden Beach
McCune B, Grace JB, Urban DL (2002) Analysis of ecological communities. MjM software design, Gleneden Beach
McNeely JA (2004) Nature vs. nurture: managing relationship between forests, agroforestry and wild biodiversity. Agrofor Syst 61:155–165
Mcneely JA, Schroth G (2006) Agroforestry and biodiversity conservation-traditional practices, present dynamics, and lessons for the future. Biodivers Conserv 15:549–554. doi:10.1007/s10531-005-2087-3
Mebrate BT (2007) Agroforestry practices in Gedeo Zone, Ethiopia: A geographical analysis. Dissertation, Panjab University
Negash M (2007) Trees management and livelihoods in Gedeo’s agroforests Ethiopia. For Trees Livelihoods 17:157–168
Negash M, Achalu N (2008) History of indigenous agroforestry in Gedeo, southern Ethiopia, based on local community interviews: vegetation diversity and structure in the landuse systems. Ethiop J Nat Resour 10(1):31–52
Nobel IR, Dirzo R (1997) Forest as human-dominated ecosystems. Science 277:522–525
Nyhus P, Tilson R (2004) Agroforestry, elephants, and tigers: balancing conservation theory and practice in human-dominated landscapes of Southeast Asia. Agric Ecosyst Environ 104:87–97. doi:10.1016/j.agee.2004.01.009
Pearce D (2007) Do we really care about biodiversity? Environ Resour Econ 37:313–333
Peyre A, Guidall A, Wiersum KF, Bongers F (2006) Dynamics of homegarden structure and function in Kerala, India. Agrofor Syst 66:101–115. doi:10.1007/s10457-005-2919-x
Philpott MS, Bichier P, Rice RA, Greenberg R (2008) Biodiversity conservation, yield, and alternative products in coffee agroecosystems in Sumatra, Indonesia. Biodivers Conserv 17:1805–1820. doi:10.1007/s10531-007-9267-2
Ponce-Hernandez R, Koohafkan P, Antoine J (2004) Assessing carbon stocks and modeling win-win scenarios of carbon sequestration through land-use changes. Food and Agriculture Organization of the United Nations (FAO), Rome
Poschen P (1986) An evaluation of the Acacia albida-based agroforestry practices in the Hararghe highlands of eastern Ethiopia. Agrofor Syst 4:129–143
Schoeneberger MM (2008) Agroforestry: working tress for sequestering carbon on agricultural lands. Agrofor Syst. doi: 10.1007/s10457-008-9123-8
Schroth GF, Harvey GAB, Vasconcelos CA, Gascon HLC, Izac AMN (2004) The role of agroforestry in biodiversity conservation in tropical landscapes, Island Press, Washington DC
Snowdon P, Raison J,Keith H, Ritson P, Grierson P, Adams M,Montagu K, Bi HQ, Burrows W, Eamus D (2002) Protocol for sampling tree and stand biomass. National Carbon accounting System, Technical report no. 31. Australian Greenhouse Office, Canberra
Soto-Pinto L, Villalvazo-Lo’Pez V, Jime’Nez- Ferrer G, Rami’Rez-Marcial N, Montoya G, Sinclair FL (2007) The role of local knowledge in determining shade composition of multistrata coffee systems in Chiapas, Mexico. Biodivers Conserv 16:419–436. doi:10.1007/s10531-005-5436-3
SPSS version 14 (2005) SPSS Inc. Headquarter 233.5. Waker Drive, 11th floor Chicago, Illinois
Tekelay T, Malmer A (2004) Decomposition of leaves from two indigenous trees of contrasting qualities under shaded-coffee and agricultural land-uses during the dry season at Wondo Genet, Ethiopia. Soil Biol Biochem 36:777–786
Tekelay T, Nordgren A, Nyberg G, Malmer A (2007) Carbon mineralization of leaves from four Ethiopian agroforestry species under laboratory and field conditions. Appl Soil Ecol 35:193–202
Teketay D, Tegineh A (1991) Traditional tree crop based agroforestry in coffee producing areas of Hararghe, Eastern Ethiopia. Agrofor Syst 16:257–267
Tesemma AB (ed) (2007) Profitable agroforestry innovations for eastern Africa: experience from 10 agro-climatic zones of Ethiopia, India, Kenya, Tanzania and Uganda. World agroforestry center, Nairobi, p 374
Tolera M, Asfaw Z, Lemenih M, Karltun E (2008) Woody species diversity in a changing landscape in the south-central highland of Ethiopia. Agric Ecosyst Environ 128:52–58. doi:10.1016/j.agee.2008.05.001
Uezu A, Beyer DD, Metzger JP (2008) Can agroforest woodlots work as stepping stones for birds in the Atlantic forest region? Biodivers Conserv 17:1907–1922. doi:10.1007/s10531-008-9329-0
Vaughan M, Black SH (2006) Agroforestry: sustaining native bee habitat for crop pollination. Agroforestry notes. USDA National agroforestry center. UNL-East Campus, Lincoin, Nebraska, p 4
Vivero LJ, Kelbessa E, Demissew S (2005) The red list of endemic trees and shrubs of Ethiopia and Eritrea. Fauna and Flora international, Cambridge, p 23
Wiersum KF (2004) Forest garden as an ‘intermediate’ land-use system in the nature-culture continuum: characteristics and future potential. Agrofor Syst 61:123–134
Yimer F, Ledin S, Abdelkadir A (2006) Soil property variations in relation to topographic aspect and vegetation community in the south-eastern highlands of Ethiopia. For Ecol Manag 232:90–99
Acknowledgments
We are grateful to the International Foundation for Science (IFS Grt. No. D/4836) and the Swedish International Development Agency (SIDA) for financial support for the study. Wondo Genet College of Forestry and Natural Resources and the University of Helsinki are also acknowledged for offering a postgraduate study opportunity for the first author. We thank the two anonymous reviewers for their valuable comments on the manuscript. Mr. Jeremy is also acknowledged for editing the language on the manuscript. We are also indebted to Gedeo farmers for sharing their marvellous experiences.
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Negash, M., Yirdaw, E. & Luukkanen, O. Potential of indigenous multistrata agroforests for maintaining native floristic diversity in the south-eastern Rift Valley escarpment, Ethiopia. Agroforest Syst 85, 9–28 (2012). https://doi.org/10.1007/s10457-011-9408-1
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DOI: https://doi.org/10.1007/s10457-011-9408-1