| Research Articles |
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| Grazing intensity effects on the vegetation in desert rangelands of Southern Tunisia |
| Mouldi GAMOUN |
| Laboratory of Range Ecology, Arid Regions Institute (IRA), Medenine 4119, Tunisia |
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Abstract Although the effects of non-grazing and heavy grazing on vegetation structure have been extensively studied in a wide range of ecosystems, the effects of moderate grazing on desert land are still largely unknown. Many management opportunities exist for increasing forage intake. In order to determine an optimal management method of desert rangelands with high heritage value, we examined the respective effects of heavy grazing, moderate grazing and non-grazing on total vegetation cover, species richness, the Shannon-Wiener diversity index and rangeland productivity. Sampling was done from 2010 to 2012 (from the second year after treatments were imposed) using permanent transects under different grazing intensities. While total vegetation cover, species richness, Shannon-Wiener diversity index, species composition and primary production were significantly greater on the ungrazed site and significantly weaker on the heavily grazed site, in contrast, moderate grazing had no significant ffect on total vegetation cover, species richness, Shannon diversity index, species composition and primary production. These studies suggest that desert rangelands plant communities in general lack response to moderate grazing disturbance, and if managed properly they can provide a valuable source of feed for livestock.
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Received: 22 April 2013
Published: 10 June 2014
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Corresponding Authors:
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| Batabyal A A, Biswas B, Godfrey B E. 2001. On the choice between the stocking rate and time in range management. Environmental and Resource Economics, 20: 211–223.Bock C E, Bock J H. 2000. The View from Bald Hill: Thirty Years in an Arizona Grassland. Berkeley: University of California Press.Briske D D, Richards J H. 1995. Plant responses to defoliation: a morphological, physiological and demographic evaluation. In: Bedunah D J, Sosebee R E. Wildland Plants: Physiological Ecology and Developmental Morphology. Society for Range Management, Denver, Colorado, USA, 635–710.Briske D D, Fuhlendorf S D, Smeins F E. 2003. Vegetation dynamics on rangelands: a critique of the current paradigms. Journal of Applied Ecology, 40: 601–614.Briske D D, Fuhlendorf S D, Smeins F E. 2006. A unified framework for assessment and application of ecological thresholds. Rangeland Ecology & Management, 59: 225–236.Briske D D, Bestelmeyer B T, Stringham T K, et al. 2008. Recommendations for development of resilience-based state-and-transition models. Rangeland Ecology & Management, 61: 359–367.Brown G, Al-Mazrooei S. 2003. Rapid vegetation regeneration in a seriously degraded Rhanterium epapposum community in northern Kuwait after 4 years of protection. Journal of Environmental Management, 68: 387–395.Christensen N L, Bartuska A M, Brown J H, et al. 1996. The report of the Ecological Society of America Committee on the scientific basis for ecosystem management. Ecological Applications, 6: 665–691.Daget P, Poissonet J. 1971. A method for phytological analysis of prairies. Annals of Agricultural, 22: 5–41.El-Kady H F. 1980. Effect of Grazing Pressures and Certain Ecological Parameters on Some Fodder Plants of the Mediterranean Coast of Egypt. MSc. Thesis, Tanta: Tank University.Eneboe E J, Sowell B F, Heitschmidt R K, et al. 2002. Drought and grazing: blue grama and western wheatgrass. Journal of Range Management, 55: 197–202.Floret C, Hadjej M. 1977. An attempt to combat desertification in Tunisia. Ambio, 6: 366−368.Floret C. 1981. The effects of protection on steppic vegetation in the Mediterranean arid zone of southern Tunisia. Vegetatio, 46: 117–129.Gamoun M. 2012. The impact of rest from grazing on vegetation dynamics: application to sustainable management of Saharan rangelands in southern Tunisia. Ph.D. Thesis, Univ. Tunis: University of Tunis El Manar, 202.Gamoun M, Tarhouni M, Ouled Belgacem A, et al. 2010a. Effects of grazing and trampling on primary production and soil surface in North African rangelands. Ekologia, 29: 219–226.Gamoun M, Chaieb M, Ouled Belgacem A. 2010b. Evolution of ecological characteristics along a gradient of soil degradation in the South Tunisian rangelands. Ecologia Mediterrania, 36: 5–16.Gamoun M, Tarhouni M, Ouled Belgacem A, et al. 2011a. Response of different arid rangelands to protection and drought. Arid Land Research and Management, 25: 372–378.Gamoun M, Ouled Belgacem A, Hanchi B, et al. 2011b. Floristic diversity variations according to management types in dry rangelands of Southern Tunisia. Ecologia Mediterrania, 37: 33–44.Gamoun M, Hanchi B, Neffati M. 2012a. Dynamics of plant communities in Saharan rangelands of Tunisia. Arid Ecosystems, 2: 105–110.Gamoun M, Ouled Belgacem A, Hanchi B, et al. 2012b. Impact of grazing on the floristic diversity of arid rangelands in South Tunisia. Revue d’Écologie (Terre Vie), 67: 271–282.Haynes M A, Fang Z, Waller D M. 2013. Grazing impacts on the diversity and composition of alpine rangelands in Northwest Yunnan. Journal of Plant Ecology, 6: 122–130.Hoffmann C, Funk R, Wieland R, Li Y, et al. 2008. Effects of grazing and topography on dust flux and deposition in the Xilingele grassland, Inner Mongolia. Journal of Arid Environments, 72: 792–807.Holechek JL. 1991. Chihuahuan Desert rangeland, livestock grazing, and sustainability. Rangelands, 13: 115−120.Hoshino A, Yoshihara Y, Sasaki T, et al. 2009. Comparison of vegetation changes along grazing gradients with different numbers of livestock. Journal of Arid Environments, 73: 687–690.Kinloch J E, Friedel M H. 2005. Soil seed reserves in arid grazing lands of central Australia. Part 1: seed bank and vegetation dynamics. Journal of Arid Environments, 60: 133–161.Le Houérou H N. 1964. Pasture lands in the Mediterranean Basin and their improvement. FAO: Goat Raising Seminar, 14.Le Houérou H N. 1969. Vegetation of the Tunisian steppe (with the references to Morocco, Algeria and Libya). Ann. Inst. Nat. Rech. Agron. Tunisia, 42 (5): 622.Le Houérou H N, Ionesco T. 1973. Species palatability of the Tunisian steppe. Tunis, FAO, Project TUN: 71/525 and TUN/69/001, 68.Le Houérou H N, Hoste C T. 1977. Rangeland production and annual rainfall relations in the Mediterranean basin and in the African Sahelo- Sudanian zone. Journal of Range Management, 30: 181–189.Le Houérou H N. 1982. Perspective and evaluation study on agricultural development: the rangeland sector. Technical Paper, UNTF/Lib 18. Tripoli; Rome: Agricultural Research Center; Food and Agriculture Organization (FAO); 77.Le Houérou H N. 2002. Man-made deserts: desertization processes and threats. Arid Land Research and Management, 16: 1–36.Loucougaray G, Bonis A, Bouzille J B. 2005. Effects of grazing by horses and/or cattle on the diversity of coastal grasslands in western France. Biological Conservation, 116: 59–71.Louhaichi M, Salkini A K, Petersen S L. 2009. Effect of small ruminant grazing on the plant community characteristics of semi-arid Mediterranean ecosystems. International Journal of Agriculture and Biology, 11: 681–689.Luo G, Han Q, Zhou D, et al. 2012. Moderate grazing can promote above-ground primary production of grassland under water stress. Ecological Complexity, 1: 126–136.Noy-Meir I, Gutman M, Kaplan Y. 1989. Responses of Mediterranean grassland plants to grazing and protection. Journal of Ecology, 77: 290–310.Peco B, Sanchez A M, Azcarate F M. 2006. Abandonment in grazing systems: consequences for vegetation and soil. Agriculture, Ecosystems and Environment, 113: 284–294.Peco B, Carmona C P, de Pablos I, et al. 2012. Effects of grazing abandonment on functional and taxonomic diversity of Mediterranean grasslands. Agriculture, Ecosystems and Environment, 152: 27–32.Reynolds J F, Smith D M S, Lambin E F. 2007. Global desertification: building a science for dryland development. Science, 316: 847–851.Röder A, Kuemmerleb T, Hilla J, et al. 2007. Adaptation of a grazing gradient concept to heterogeneous Mediterranean rangelands using cost surface modeling. Ecological Modeling, 204: 387–398.Schonbach P, Wan H, Schiborra A, et al. 2009. Short-term management and stocking rate effects of grazing sheep on herbage quality and productivity of Inner Mongolia steppe. Crop Pasture Science, 60: 963–974.Society of Range Management (SRM). 2003. Biodiversity of rangelands. Rangelands, 25: 60–65.Sternberg M, Gutman M, Perevolotsky A, et al. 2000. Vegetation response to grazing management in a Mediterranean herbaceous community: a functional group approach. Journal of Applied Ecology, 37: 224–237.Thalen D C P. 1979. Ecology and Utilization of Desert Shrub Rangelands in Iraq. The Netherlands: Junk. 430.Wang Y S, Shiyomi M, Tsuiki M, et al. 2002. Spatial heterogeneity of vegetation under different grazing intensities in the Northwest Heilongjiang Steppe of China. Agriculture, Ecosystems and Environment, 90: 217–229.Zahran M A. 2010. Climate–Vegetation. Afro-Asian Mediterranean and Red Sea Coastal Lands. Plant and Vegetation. London New York: Springer Dordrecht Heidelberg, 344.Zhao W Y, Li J L, Qi J G. 2006. Changes in vegetation diversity and structure in response to heavy grazing pressure in the Northern Tianshan Mountains, China. Journal of Arid Environments, 68: 337–508. |
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