Effects of Grazing Exclusion on Plant Productivity and Carbon Sequestration (Case Study: Gomishan Rangelands, Golestan Province, Iran)


1 Assistant Professor of Rangeland Management Department, University of Agricultural Sciences and Natural Resources, Gorgan, Iran

2 Ph.D. Student of Rangeland Management, University of Agricultural Sciences and Natural Resources, Gorgan, Iran

3 M.Sc. Student of Rangeland Management, University of Agricultural Sciences and Natural Resources, Gorgan, Iran


 In recent years, rangelands have been regarded as potential carbon sinks. One of the most widely suggested options to sequester more C in rangelands is the restoration of the degraded rangelands through grazing the exclusion. In present study, the effects of exclusion on the carbon sequestration of Gomishan rangelands were investigated. Three transects were established in a key area inside and outside the exclosure. In each transect, ten plots were established systematically and in each plot, the number of plant individuals for each plant species was recorded and used to estimate the density of each species per unit area. In order to estimate the plant biomass, a few individuals of each species were sampled by the clipping and weighing method. The carbon content of aerial and root biomass were obtained by the combustion of 10 g of oven-dried samples. Five soil samples at the depths of 0–10 and 10–20 cm were taken along each transect and then, transported to the laboratory. The soil organic carbon percent was determined by the Walkley–Black method. Plant data analysis was performed by one way analysis of variance (ANOVA) and Tukey test. The rate of soil carbon sequestration inside and outside the exclosure was compared using the independent T test at significance level of 1%. Finally, the economic benefit of sequestrated carbon was estimated. The results revealed that the response of plant and soil carbon storage to the exclosure in Gomishan rangelands was positive and there was a significant difference between exclosure and grazing areas for the stored carbon of plant biomass and soil. After a 20 year exclosure, the value of carbon sequestration per hectare in Gomishan rangelands was estimated as 14743 $/h. It can be argued that the education and extension of carbon sequestration in Iran will offer new incentives to restore the degraded rangelands.


Abril, A. and Bucher, E. H., 2001. Overgrazing and soil carbon dynamics in the western Chaco of Argentina. Applied Soil Ecology. 16: 243–249.

Archer, S., 1995. Tree–grass dynamics in a Prosopis-thornscrub savanna parkland: reconstructing the past and predicting the future. Ecoscience. 2 (1): 83–99.

Birdesy, R. A., 1996. Regional estimate of timber volume and forest carbon for fully Stocked timberland, Averse management after final clear cut harvest in forest and global change. Volume 2, Forest Management Opportunities for Mitigating Carbon Emissions. Sampson, Eds. R.N., Hair, D. American Forest, Washington. D.C.

Boix-Fayos, C., Calvo-Cases, A., Imeson, A. C. and Soriano-Soto, M. D., 2001. Influence of soil properties on the aggregation of some Mediterranean soils and the use of aggregate size and stability as land degradation indicators. CATENA. 44 (1): 47–67.

Canadell, J. G., 2002. Land use effects on terrestrial carbon sources and sinks. Science in China. 45: P: 1-9.

Conant, R. T., Paustian, K. and Elliott, E. T., 2001. Grassland management and conversion into grassland: effects on soil carbon. Ecological Applications, 11: 43–355.

Derner, J. D., Briske, D. D. and Boutton, T. W., 1997. Does grazing mediate soil carbon and nitrogen accumulation beneath C4 perennial grasses along an environmental gradient? Plant Soil, 191 (2): 147–156.

Derner, J. D. and Schuman, G. E., 2007. Carbon sequestration and rangelands: A synthesis of land management and precipitation effects. Jour. Soil and Watershed Conservation, 62(2): 77-85.

Eskandari, N., Alizadeh, A. and Mahdavi, F., 2008. Range management policies in Iran. Poneh publications, Tehran, Iran. 190 P. (In Persian).

Evrendilek, F., Celik, I., Kilic, S., 2004. Changes in soil organic carbon and other physical soil properties along adjacent Mediterranean forest, grassland, and cropland ecosystems in Turkey. Jour. Arid Environments, 59 (4): 743–752.


Ferguson, D. F., 2003. Carbon Sequestration on Idaho Agriculture and Forest lands. Technical Report of Idaho Soil Conservation Commission, P: 30-35.

Follett, R. F., Kimble, J. M. and Lal, R., 2001. The potential of U.S. grazing lands to sequester carbon and mitigate the greenhouse effect.Boca Raton, Florida, USA, Lewis Publishers, CRC Press. 422 pp.

Finer, L., 1996. Variation in the amount and quality of litterfal in a Pinus sylvestris L. stand growing on a bog. Forest Ecology and Management, 80: 1-11.

Forouzeh, M. R., 2007. Effect of exclusion on carbon sequestration potential of Halocnemum strobilaceum and Halostachys caspica (Case study: Gomishan rangelands). Watershed Management Research, 85: 22-28 (In Persian).

Fynn, A. J., Alvarez, P., Brown, J. R., George, M. R., Kustin, C., Laca, E. A., Oldfield, J. T., Schohr, T., Neely, C. L. and Wong, C. P., 2010. Soil carbon sequestration in USA rangelands. Integrated Crop Management, 11: 57-104.

Ghorbani, N., Raiesi, F., Ghorbani, S., 2012. Bulk soil and particle size-associated C and N under grazed and ungrazed regimes in Mountainous arid and semi-arid rangelands. Nutr. Cycl. Agroecosyst, 93: 15–34.

Glenn, E., Stafford Smith, M. and Squires, V., 1998. On our failure to control desertification: implications for global change issues, and a research agenda for the future. Environmental Science & Policy, 1(2): 71–78.

Golluscio, R. A., Deregibus, V. A. and Paruelo, J. M., 1998. Sustainability and range management in the Patagonian steppes. Ecologı´a Austral., 8: 265–284.

Haynes, R. J. and Naidu, R., 1998. Influence of lime, fertilizer and manure applications on soil organic matter content and soil physical conditions: a review. Nutrient Cycling in Agro Ecosystems, 51 (2): 123–137.

Houghton, J. T., Ding, Y. and Griggs, D., 2001. Climate Change, 2001, the Science of Climate Change. Cambridge: Cambridge University Press.

Ingram, L. J., Stahl, P. D., Schuman, G. E., Buyer, J. S., Vance, G. F., Ganjegunte, G. K., Welker, J. M. and Derner, J. D., 2008. Grazing impacts on soil carbon and microbial communities in a mixed-grass ecosystem. Soil Sci. Soc. Am. Jour., 72: 939-948.

IPCC (Intergovernmental Panel on Climate Change), 2000. Land use, land-use change, and forestry. In: R.T. Watson et al., eds. Special Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, UK,. 377 pp.

Jeddi, K. and Chaieb, M., 2010. Changes in soil properties and vegetation following livestock grazing exclusion in degraded arid environments of South Tunisia. Flora, 205:184–189.

Kimble, J. M., Follett, R. F. and Lal, R., 2001. Introduction: the characteristics and extent of US grazing lands. In: Follett, R. F., Kimble, J. M., Lal, R. (Eds.), The Potential of U.S. Grazing Lands to Sequester Carbon and Mitigate Greenhouse Effect. Lewis Publishers, BocaRaton, FL, pp. 3–20.

Lal, R., 1999. Soil management and restoration for C sequestration to mitigate the accelerated greenhouse effect. Prog. Environ. Sci., 1: 307–326.

Lal, R., 2002. Soil carbon dynamics in cropland and rangeland. Environmental Pollution, 116: 353–362.

Lal, R., 2004. Soil carbon sequestration to mitigate climate change. Geoderma, 123: 1–22.

Lehmann, J. and Joseph, S., 2009. Biochar for environmental management: an introduction. In: Lehmann, J. and Joseph, S. (eds.) Biochar for Environmental Management: Science and Technology. Earthscan Publ., London, pp. 1-12.

Lemma, B., Kleja, D. B., Nilsson, I. and Olsson M., 2006. Soil carbon sequestration under different exotic tree species in the southwestern highlands of Ethiopia. Geoderma, 136: 886-898.

Loveland, P. and Webb, J., 2003. Is there a critical level of organic matter in the agricultural soils of temperate regions: a review. Soil and Tillage Research, 70 (1): 1–18.

Lund, H. G., 2007. Accounting for the world’s rangelands. Rangelands, 29: 3–10.