نوع مقاله : مقاله پژوهشی

نویسندگان

دانشگاه ولیعصر رفسنجان

چکیده

در مقیاس­طول عمر انسان، خاک یکی از منابع طبیعی اصلی تجدید ناپذیر در جهان است. تخریب خاک یک تهدید جدی در جهان به شمار می‌رود، زیرا در درازمدت باعث کاهش توان تولید زیستی، اقتصادی خاک و ناپایداری محیط زیست می‌شود. در نتیجه ارزیابی عوامل مؤثر در تخریب خاک و تعیین مناطق مبتلا به این معضل، در حفاظت خاک اهمیت بسزایی دارد. یکی از مناسب‌ترین روش‌ها جهت ارزیابی تخریب خاک، روش فائو یونپ می‌باشد که در آن فاکتورهای متعدد فیزیکی و شیمیایی خاک مورد بررسی قرار می‌گیرد. هدف از انجام این پژوهش ارزیابی تخریب خاک به روش کمی فائو و یونپ در اراضی دشت جوپار می‌باشد. به همین منظور، ابتدا محل 46 نقطه نمونه‌برداری (شامل 16 مته و 30 خاکرخ) با روش شبکه‌ای منظم، بر روی نقشه توپوگرافی منطقه با مساحت 90 کیلومتر مربع و مقیاس 1:25000 تعیین شدند. درنهایت پس از تعیین ویژگی­های شیمیایی و فیزیکی 184 نمونه خاک به روش‌های استانداردآزمایشگاهی، در هر یک از اجزای واحد اراضی، ویژگی­های یک خاکرخ شاهد، مورد طبقه‌بندی نهایی و ارزیابی قرارگرفت. در این پژوهش تاًثیر ویژگی­های شیمیایی (شوری، سدیمی بودن و آلودگی آب­های زیرزمینی) و ویژگی­های فیزیکی (تراکم خاک و عمق آب زیرزمینی) بر روی تخریب خاک با استفاده از رابطه­ها و ضرایب وزنی ارائه­شده در روش فائو یونپ ارزیابی شد و خطر تخریب خاک منطقه به­دست آمد. نتایج ارزیابی مشخص کرد که 2/39 درصد از کل منطقه مورد مطالعه که اراضی قابل کشت را تشکیل می­دهند، در معرض خطر تخریب اراضی قرارگرفته­اند؛ به­طوری­که 2/28 درصد کل منطقه به­دلیل خطرات تخریب شیمیایی در کلاس تخریب خیلی زیاد و 11 درصد اراضی از این نظر در کلاس تخریب متوسط ارزیابی می­گردند. نتایج موید این مطلب است که در ایجاد خطر تخریب شیمیایی عامل شوری ایجادشده ناشی از سازند زمین­شناسی شور که با اقلیم خشک منطقه تاثیر آن دوچندان شده، موثر است. در بروز تخریب فیزیکی اراضی منطقه نیز عامل تراکم در اثر چرای بی­رویه دام­ها مؤثرترین ­عامل بر اساس مدل فائو-یونپ معرفی می­گردد که در کلاس تخریب با خطر کم طبقه­بندی شدند.

کلیدواژه‌ها

عنوان مقاله [English]

The Assessment of Soil Degradation Risk using Quantitative FAO / UNEP Method in Joupar Plain, Kerman Province

نویسنده [English]

  • Ardavan Kamali

چکیده [English]

Abstract
Soil is the main nonrenewable natural source in the world. Soil degradation is the main threat across the globe and cause to decrease the soil ability in economical and biological production as well as environmental Instability. Therefore, the consideration of affective factors of soil degradation and determination of regional solutions has an important role in using and protecting soils. One of the suitable methods in studying the soil degradation is FAO/ UNEP method that studies different soil physical and chemical factors. The purpose of this research, therefore, was to study the soil degradation in Joupar plain by quantitative FAO/ UNEP method approach.  To do this research, the 46-point sampling (auger and profile) on topographic map with a scale of 1: 25,000 with regular network, was determined. Finally, in each land unit components, a control profiles, the sampling was done and the final classification. The chemical and physical properties of soil were determined by conventional methods. The effect of chemical properties (salinity and alkalinity) and physical properties (density, soil and water table depth) on soil degradation using the formula and weighting coefficients presented in FAO - UNEP assessment and destruction of soil was obtained. The results of this study showed that the total of 39.2 percent of the studied lands were prone to the chemical soil degradation in which 28.2 percent of the area were classified as very high and 1l percent classified as low risk in this regard. The total physical degrading risk of the studied lands were determined about 39.2 percent in which 28.2 percent of the lands classified as low risk while 11 percent were considered at medium level of degradation risk. It was also found physical properties density had the greatest impact on the destruction area.

کلیدواژه‌ها [English]

  • Soil salinity and sodicity risk
  • Soil compaction
  • Soil conservation
  • Joupar
  • Sustainable soil management
References
Arya A.S., Dhinwa P.S., Pathan S.K., and Ganesh K. 2009. Desertification land degradation status mapping of India. Current Science, 10: 1478-1483.
Asio V.B., Jahn R., Perez F.O., Navarrete I.A., and Abit, S.M. 2009. A review of soil degradation in the Philippines. Annals Tropical Research, 2: 69-94.
 Banaei M.H. 1998. Soil Moisture and Temperature Regime Map of Iran. Soil and Water Research Institute, Ministry of Agriculture, Iran.
Darvish M. 2004. Assessment and mapping of desertification by FAO/UNEP in the watershed Salt Lake. Research Institute of Forest and Rangelands, 46p (In Persian)
El Baroudy A.A. 2011. Monitoring land degradation using remote sensing and GIS techniques in an area of the middle Nile Delta, Egypt. Catena, 87: 201-208.
El Baroudy A.A., and Moghanm F.S. 2014. Combined use of remote sensing and GIS for degradation risk assessment in some soils of the Northern Nile Delta, Egypt. The Egyptian Journal of Remote Sensing and Space Sciences, 17(1):77-85.
FAO/UNEP. 1978. Methodology for Assessing Soil Degradation. Rome, 89p.
Fernandez Buces N., Siebe C., Cram S.J., and Palacio L. 2006. Mapping soil salinity using a combined spectral response index for bare soil and vegetation: A case study in for bare soil and vegetation study in the former lake Texcoco, Mexico. Arid Environment, 65: 644-667.
Gee, G. W., and Bauder J. W. 1986. Particle size analysis. American Society of Agronomy, 383-411.
Geological Survey and mineralogical exploration of Iran, 1998. Kreman 1:100000 geologic map. Geological Survey and mineralogical exploration of Iran, Tehran, Iran.
Jones G.B. 2001. Laboratory guide for conducting soil tests and plant analysis. CRC Press, Boca Raton, Florida, 382p.
Khan N., Victor V., Rastoskuev B., Sato A.S., and Shiozawa A. 1988. Assessment of hydrosaline land degradation by using a simple approach of remote sensing indicators. International Journal Agricultural Water Management, 77(1): 96-109.
Kerman meteorological organization. 2015. Www. weather.kr.ir. (In Persian)
Kerman natural resources organization. 2015. Www. Kerman.frw.org.ir. (In Persian)
Ladisa G., Todorovich M., and Trisorio G. 2002. Characterization of area sensitive to desertification in southern Italy. Proceedings of the 2nd International Conference “New Trends in Water and Environmental Engineering for Safety and Life: Eco-compatible Solutions for Aquatic EnvironmentsCapri, Italy, pp. 54-55.
Lanyon L.E., and Heald W.R. 1982. Magnesium, calcium, strontium and barium. American Society of Agronomy, 9:247-273.
Nelson D.W., and Sommers L.E. 1996. Total carbon, organic carbon, and organic matter. In: Sparks D.L. (Ed.), Methods of Soil Analysis, Part 3. American Society of Agronomy. Inc., Madison, WI, USA, 961-1010.
Nelson R.E. 1982. Carbonate and Gypsum. In: Page A.L. (Ed.), Methods of Soil Analysis, Part 2. Chemical and Microbiological properties, Agronomy Monograph, 9:181-197.
NSSC. 2008. Review of mainstreaming of sustainable land management in government policies and plans in Bhutan. National Soil Services Center Ministry of Agriculture, Thimphu, 134p.
Oldeman L.R., Hakkeling R.T.A., and Sombrock W.G. 1991. World Map of the Status of Human-Induced Soil Degradation. Land Degradation and Development, 3(1):68-69.
Rahimi M., Damavandi, A., and Jafarian V. 2011. Review application of remote sensing to assess and monitor land degradation and desertification. Journal Management System, 22(88): 115-128. (In Persian)
Rhoades J.D. 1996. Salinity Electrical conductivity and total dissolved soils. In D.L. Sparks (ed.), Methods of Soil Analysis, Part 3: Chemical Methods, SSSA Book Series Number 5, Soil Science Society of America, 417-435.
Safiyari R., Sarmadian F., Heidari A., and Younesi SH. 2013.  Land vulnerability evaluation related to erosion and climate change impacts in Abyek region with use of Microleis system. Journal of Range and Watershed Management, 66(3): 417-431. (In Persian)
Silva J.A., and Hue N.V. 2000. Organic soil amendments for sustainable agriculture: organic sources of nitrogen, phosphorus, and potassium. Plant nutrient management in Hawaii soils. Approaches for tropical and subtropical agriculture. Agriculture and Human Resources, 133-144.
Soil survey staff. 2014. Keys to Soil Taxonomy, 13th Ed. NRCS, USDA, USA, 372p.
Szabolcs I. 1991. Desertification and salinization. In: R. Choukr-allah Editor Plant Salinity Research. Proceedings of the International Conference Agricultural Management of Salt affected Areas, 26 April-3 May, Morocco, pp. 3-18.
Thomas G.W. 1996. Soil pH and soil acidity. In D.L. Sparks (ed.), Methods of Soil Analysis, Part 3: Chemical Methods, SSSA Book Series Number 5, Soil Science Society of America, Madison, 475-490.
Tickell S. J .1977. Mapping dryland salinity hazard, Northern Territory, Australia. Hydrogelogy Journal, 5:109-117.
Wahab M.A., Rasheed M.A., and Youssef R.A. 2010. Degradation hazard assessment of some soils North Nile Delta, Egypt. Journal of American Science, 6(6):156-161.
Wang Y., Fu B., Lu Y., Song CH., and Luan Y. 2012. Local_scale spatial variability of soil organic carbon and its stock in the hilly area of the loess plateau, China. Quaternary Research, 73: 70-76.
Zhao W.Z., Xiao H.L., Liu Z.M., and Li J. 2005. Soil degradation and restoration as affected by land use change in the semiarid Bashang area, northern China, Catena, 59(2): 173-186.
Zehtabian GH., Rafiei Emam A., Alavipanah S.K., and Jafari M. 2004. Survey of Varamin Plain ground water for use on Farm lands irrigation. Geographical Research Quarterly, 36(48): 91-102. (In Persian)