| Research Articles |
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| Effects of exotic and endogenous shrubs on under-story vegetation and soil nutrients in the south of Tunisia |
| Zouhaier NOUMI* |
| Department of Life Sciences, Faculty of Sciences, University of Sfax, Sfax 3000, Tunisia |
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Abstract This study was conducted in southern Tunisia in the growing seasons of 2013 and 2014, and aimed to compare the effects of exotic and endogenous shrub species (Haloxylon persicum and Retama raetam, respectively) on understory vegetation and soil nutrients. For each shrub species, the canopied sub-habitat (under the shrub crown) and un-canopied sub-habitat (in open grassland area) were distinguished. The concentrations of soil nutrients (organic matter, total nitrogen and extractable phosphorus) were found to be significantly higher (P<0.05) under R. raetam canopy than under H. persicum canopy and in open area. The result also showed that the presence of shrubs improved all the values of understory vegetation parameters (floristic composition, density, total plant cover and dry matter) and all these values were significantly higher under endogenous species canopy than under exotic species canopy. These results highlighted the positive effect of endogenous shrubs on understory vegetation and soil nutrients compared to the exotic ones in the Saharan areas of Tunisia.
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Received: 22 November 2014
Published: 10 August 2015
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Corresponding Authors:
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| Abdallah F, Noumi Z, Touzard B, et al. 2008. The influence of Acacia tortilis (Forssk.) subsp. raddiana (Savi) and livestock grazing on grass species composition, yield and soil nutrients in arid environments of South Tunisia. Flora, 203: 116–125.Abdallah F, Noumi Z, Ouled Belgacem A, et al. 2012. The influence of Acacia tortilis (Forssk.) ssp. raddiana (Savi) Brenan presence, grazing, and water availability along the growing season, on understory herbaceous vegetation in southern Tunisia. Journal of Arid Environments, 76: 105–114.Aerts R, Maes W, November E, et al. 2006. Surface runoff and seed trapping efficiency of shrubs in regenerating semiarid wooland in northern Ethiopia. Catena, 65: 61–70.Aguiar M R, Sala O E. 1999. Patch structure, dynamics and implications for the functioning of arid ecosystems. Trends in Ecology and Evolution, 14: 273–277.Al-Naib F A G, Al-Mousawi A H. 1976. Allelopathic effects of Eucalyptus microtheca. Kuwait Journal of Science, 3: 83–87.Alpert P, Bone E, Holzapfel C. 2000. Invasiveness, invasibility and the role of environmental stress in the spread on non native plants. Perspectives in Plant Ecology, Evolution and Systematics, 3: 52–66.Badano E I, Perez D, Vergara C H. 2009. Love of nurse plants is not enough for restoring oak forests in a seasonally dry tropical environment. Restoration Ecology, 17: 571–576. Belsky A J, Amundson R G, Duxburg J M, et al. 1989. The effects of trees on their physical, chemical, and biological environments in a semi-arid savanna. Journal of Applied Ecology, 26: 1005–1024.Callaway R M, Nadkarni N M, Mahall R E. 1991. Facilitation and interference of Quercus douglasii on understory productivity in central California. Ecology, 72: 1484–1499.Casati P, Andrew C S, Edward G E. 1999. Characterization of NADP-malic enzyme from two species of Chenopodiaceae: Haloxylon persicum (C4) and Chenopodium album (C3). Phytochemistry, 52: 985–992.Castillo V M, Martinez-Mena M, Albaladejo J. 1997. Runoff and soil loss response to vegetation removal in a semiarid environment. Soil Science Society of America Journal, 61: 1116–1121.Cortina J, Maestre F T. 2005. Plant effects on soils in drylands: Implications for community dynamics and dryland restoration. In: Binkley D, Menyailo O. Tree Species Effects on Soils: Implications for Global Change. Dordrecht: Kluwer NATO Science Series Academic Publishers, 85–118.Cowling R, Rundel P, Lamont B, et al. 1996. Plant diversity in Mediterranean-climate regions. Trends in Ecology and Evolution, 11: 362–366.David L, Hodge J, Kuzyakov A. 2004. Plant and mycorrhizal regulation of rhizodeposition. New Phytologist, 163: 459–480.Davis M A, Wrage K J, Reich P B. 1998. Competition between tree seedlings and herbaceous vegetation: support for a theory of resource supply and demand. Journal of Ecology, 86: 652–661.Davis M A, Grime J P, Thompson K. 2000. Fluctuating resources in plant communities: a general theory of invasiblity. Journal of Ecology, 88: 528–534.Davis S D, Heywood V H, Hamilton A C. 1994. Centres for Plant Diversity: A Guide and Strategy for their Conservation. Cambridge: World Wide Fund for Nature (WWF), International Union for Conservation of Nature (IUCN), 354.Del Moral R, Muller C H. 1969. The Allelopathic effect of Eucalyptus camaldulensis. American Midland Naturalist, 83: 254–282.Delanoë O, de Montmollin B, Olivier L, et al. 1996. Conservation of Mediterranean Island Plants. 1. Strategy for Action. Cambridge: IUCN, 114.Derbel S. 2012. Ecological status and adaptive and functional strategies of some North African Saharan plant species. PhD Dissertation. Sfax: University of Sfax.di Castri F, Hansen A J, Debussche M. 1990. Biological Invasions in Europe and the Mediterranean Basin. Dordrecht: Kluwer Academic Publishers, 217–227.Díaz Barradas M C, Zunzunegui M, Tirado R, et al. 1999. Plant functional types and ecosystems function in a Mediterranean shrubland. Journal of Vegetation Science, 4: 709–716.Espigares T, López-Pinto A, Rey Benayas J M. 2004. Is the interaction between Retama sphaerocarpa and its understorey herbaceous vegetation always reciprocally positive? Competition–facilitation shift during Retama establishment. Acta Oecologica, 26: 121–128.Facelli J M, Brock D J. 2000. Patch dynamics in arid lands: localized effects of Acacia papyrocarpa on soils and vegetation of open woodlands of south Australia. Ecography, 23: 479–491.Facelli J M, Temby A M. 2002. Multiple effects of shrubs on annual plant communities in arid lands of South Australia. Austral Ecology, 27: 422–432. |
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