Impact of Bush Encroachment Control on Rangeland Vegetation in the Rangelands of Bale, Southeastern Ethiopia
محورهای موضوعی : Arid Land ManagementMahammed Abdullahi 1 , Abdunaser Birka 2
1 - Haramaya University, College of Agriculture and Environmental Science, School of Animal and Rangeland Science
2 - Natural Resource Management, College of Agriculture and Natural Resource, Madda Walabu University, Robe, Ethiopia
کلید واژه: Vegetation dynamics, Bale rangeland, Bush control, Grass and forbs,
چکیده مقاله :
This study was conducted to examine impact of bush encroachment control on rangeland vegetation in the south eastern Ethiopia. The study targeted two main and dominant encroaching woody plant species, Acacia bussei and Acacia aerfota, and their effects on rangeland vegetation attribute dynamics in Raitu district of Bale zone, southeastern Ethiopia for two consecutive years. Rangeland site encroached by these two acacia species was replicated/divided into three plots, and each plot was subdivided into five sub-plots receive five treatments: cutting at 0.5 m above ground alone (T1), cutting at 0.5 m above ground and dissecting the stumps (T2), cutting at 0.5 m above ground and pouring chemicals on stumps (T3), cutting at 0.5 m above ground and debarking the stumps down into the soil surface (T4) and control (T5). Data on biomass, species richness, basal and litter covers, soil erosion and compaction, dead and re-sprouted encroaching tree/shrub species were collected. The applied treatments significantly influenced (P<0.05) basal cover, dry matter and the two encroaching tree species. The results of this study showed that T1 and T4 were good in controlling A. aerfota in that order. T4 and T3 had a significant effect on controlling A. bussie in their order. The most dominant grass and non-grass species observed after the control actions were Cenchrus ciliaris, Bothriochloa radicans, Hibiscus aponerus, Pennisetum mezianum, Lintonia nutans, Chrysopogon plumulosus and Eragrostis papposa. Therefore, controlling encroaching tree/shrub species had created a conducive grazing area with palatable herbaceous species for the livestock. The management of bush encroachment will contribute to stabilize rangelands and to minimize the negative effects of feed and food crises in the future.
Abate, T., Ebro, A., Nigatu, L., 2010. Traditional rangeland resource utilization practices and pastoralists' perceptions on land degradation in south-east. Trop. Grassl. 44(2010):202-212.
Abule, E., Snyman, H.A. and Smit, G.N., 2007. Rangeland evaluation in the Middle Awash valley of Ethiopia: III. Relationships among soil and vegetation variables. Journal of Arid Environments 70: 293–303.
Angassa, A. and Oba, G., 2008. Effects of management and time on mechanisms of bush encroachment in southern Ethiopia. African Journal of Ecology 46:186-196.
Angassa, A. and Oba, G., 2010. Effects of grazing pressure, age of enclosures and seasonality on bush cover dynamics and vegetation composition in southern Ethiopia. Journal of Arid Environments 74:111-120.
Angassa, A., Oba, G. and Tolera, A., 2011. Bush encroachment control demonstrations and management implications on herbaceous species in savannas of southern Ethiopia. Tropical and Subtropical Agroecosystems, 15: 173-185.
Bolo, P.O., Sommer, R., Kihara, J., Kinyua, M., Nyawira, S. and Notenbaert, A., 2019. Rangeland degradation: Causes, consequences, monitoring techniques and remedies. Working Paper. CIAT Publication No. 478. International Center for Tropical Agriculture (CIAT). Nairobi, Kenya. 23 p. Available at: https://hdl.handle.net/10568/102393
Baars, R.M., Chileshe, E.C. and Kalokoni, D.M., 1997. Technical notes: Range condition in high cattle density areas in the Western Province of Zambia. Tropical Grasslands 31: 569–573.
Briske, D.D., Fuhlendorf, S.D. and Smeins, F.E., 2003. Vegetation dynamics on rangelands: A critique of the current paradigms. Journal of Applied Ecology 40: 601–614.
Casado, M.A., Castro, I., Ramirez-Sanz, L., Costa-Tenorio, M., de Miguel, J.M. and Pineda, F.D., 2004. Herbaceous plant richness and vegetation cover in Mediterranean grasslands and shrublands. Plant Ecology 170: 83–91.
Clark, D.L. and Wilson, M.V., 2001. Fire, mowing and hand removal of woody species in restoring a native wetland prairie in the Willamette Valley of Oregon. Wetlands 21: 135–144.
Clayton, W. D., Harman, K.T., Williamson, H., 2002. World grass species: descriptions, identification, and information retrieval. http://www.kew.org/data/grasses-db.html.
CSA, 2015. Central Statistical Agency of Ethiopia, Annual Report. http://www.csa.gov.et /index.php/2013-02-20-13-43-35/national-statistics- abstract/141-population
Flintan, F., Tache, B., Eid, A., 2011. Rangeland fragmentation in traditional grazing areas and
its impact on drought resilience of pastoral communities: lessons from Borana, Oromia and Harshin, Somali Regional States, Ethiopia. Regional Learning and Advocacy Programme
Gemedo, D.T., Brigitte L.M. and Johannes, I., 2006a. Encroachment of woody plants and its impact on pastoral livestock production in the Borana lowlands, southern Oromia, Ethiopia. East African Wild Life Society, African Journal of Ecology, 44: 237–246.
Gemedo, D.T., Maass, B.L. and Isselstein, J., 2006b. Rangeland condition and trend in the semiarid Borana lowlands, southern Oromia, Ethiopia. African Journal of Range and Forage Science, 23: 49–58.
Hedberg, I., Edwards, S., 1989. Flora of Ethiopia. Vol. 3. The National Herbarium, Addis Ababa, Ethiopia. 660p.
Jiang, Z., Wang, Z. and Liu, Z., 1996. Quantitative study on spatial variation of soil erosion in a small watershed in the loess hilly region. Journal of Soil Erosion and Soil and Water Conservation, 2:1–9.
Karuaera, N.A.G., 2011. Assessing the effects of bush encroachment on species abundance, composition and diversity of small mammals at the Neudamm Agricultural Farm, Khomas Region, Namibia. MSc. Thesis, University of Namibia and Humboldt-universitat Zu Berlin, 136pp.
Lesoli, M.S., Gxasheka, M., Solomon, T.B., Moyo, B., 2013. Integrated plant invasion and bush encroachment management on Southern African rangelands management. Available at: https://www.intechopen.com/book.
Mussa, M., Habtamu, T. and Yared, M., 2017. Land use/cover change analysis and local community perception towards land cover change in the lowland of Bale rangelands, Southeast Ethiopia. Int. J. Biodivers. Conserv 9(12): 363-372.
Mussa, M., Abule, E., Lisanework, N. and Habtamu, T., 2018. Response of herbaceous vegetation to woody plant species in the rangelands of eastern Ethiopia. Tropical and Subtropical Agroecosystems, 21: 177-187.
Negasa B., Bedasa, E., Samuel, T., Barecha, B., Jaldesa, D. and Nizam, H., 2014. Control of bush encroachment in Borana zone of southern Ethiopia: effects of different control techniques on rangeland vegetation and tick populations. Pastoralism: Research, Policy and Practice 4:18.
Olson, R.A. and Whitson, T.D., 2002. Restoring structure in late-successional sagebrush communities by thinning with tebuthiuron. Restoration Ecology 10:146-155.
Phillips, S., 1995. Flora of Ethiopia and Erithrea. POACEAE (GRAMINEAE). Hedberg, I. and S. Edwards (eds.), Vol. 7. The National Herbarium, Addis Ababa, Ethiopia. 660p.
Richter, C.G.F., Snyman, H.A., Smit, G.N., 2001. The influence of tree density on the grass layer of three sem-arid savanna types of southern Africa. Afr. J. Range Forage Sci. 18, 103–109.
Smith, K., Barrett, C.B. and Box, P.W., 2000. Participatory risk mapping for targeting research and assistance: With an example from east African pastoralists. World Development, 28(11):1945–1959.
Teka, H., Madakadze, I.C., Hassen, A., Angassa, A., and Abdulahi, M., 2018. Impacts of a mineral lick-centred land use system on woody vegetation cover in an East African Savannah. African Journal of Ecology; 2018:1–10. https://doi.org/10.1111/ aje.12503.
Worku, B. and T/Yohannes, B., 2018. Effect of Post Bush Clearing Management Practice on Herbaceous Species Productivity and Soil Status of Rangelands in Hammer District of South Omo Zone. J Agri Sci Food Res 9: 229.
Zerga, B., 2015. Rangeland degradation and restoration: a global perspective Point. Journal of Agriculture and Biotechnology Research 1:37-54.