ارزیابی بازیابی بلندمدت وزن مخصوص ظاهری، تخلخل و مقاومت به نفوذ خاک 20 سال پس از عملیات چوبکشی در جنگل خیرود

نوع مقاله : علمی- پژوهشی

نویسندگان

1 دانشجوی کارشناسی ‏ارشد مهندسی جنگل، دانشکده منابع طبیعی دانشگاه تهران

2 دانشیار، گروه جنگل‌داری و اقتصاد جنگل، دانشکده منابع طبیعی دانشگاه تهران

3 استاد، گروه جنگل‌داری و اقتصاد جنگل، دانشکده منابع طبیعی دانشگاه تهران

4 دانشجوی دکتری جنگل‌داری، دانشکده منابع طبیعی دانشگاه تربیت مدرس

چکیده

تخریب جنگل به‌طور همزمان با تخریب خاک شروع می‏شود. حفاظت و نگهداری خاک باعث حفاظت و نگهداری جنگل می‌‌شود، بنابراین مهندسی جنگل باید سعی در توسعه فنونی داشته باشد که میزان تخریب خاک کمتر و زمان بازیابی آن کوتاه‏تر باشد. پژوهش پیش‌رو به‌منظور ارزیابی بازیابی وزن مخصوص ظاهری و مقاومت به نفوذ خاک­های کوبیده شده در مسیرهای چوبکشی رها شده بعد از یک دوره 20ساله در جنگل خیرود انجام شد. چهار مسیر چوبکشی انتخاب شد و در هر یک از آنها سه طبقه شدت تردد و دو طبقه شیب مشخص شد تا نمونه­ گیری در محل رد چرخ­ها در قطعه‌نمونه‌های 40 مترمربعی انجام شود. برای نمونه­ گیری در داخل جنگل، به‌ فاصله 20 تا 30 متر از مسیرهای چوبکشی، قطعه‌نمونه‌های شاهد مستقر شدند تا روند بازیابی خاک در مسیرهای چوبکشی با منطقه شاهد با استفاده از آزمون چندگانه دانکن مقایسه شود. نتایج نشان داد که بیشترین مقدار وزن مخصوص ظاهری و مقاومت به نفوذ خاک و کمترین مقدار تخلخل در شدت تردد زیاد و شیب ببیشتر از 20 درصد است. وزن مخصوص ظاهری و تخلخل در محل­ های مختلف رد چرخ در مسیرهای چوبکشی با گذشت 20 سال، بیشتر و کمتر از منطقه شاهد بود، اما اختلاف آنها معنی­ دار نبود، درحالی که این اختلاف درمورد مقاومت به نفوذ معنی­ دار بود. با گذشت 20 سال از عملیات چوبکشی، ویژگی‌های فیزیکی خاک در حال بازیابی هستند، به‌طوری‌‌که وزن مخصوص ظاهری و مقاومت به نفوذ به‌اندازه 12/75 و 23/30 درصد بیشتر و تخلخل به مقدار 9/74 درصد کمتر از منطقه شاهد بود. این اختلاف برای وزن مخصوص ظاهری و تخلخل معنی ­دار نبود، اما برای مقاومت به نفوذ معنی­ دار بود. نتایج به‌دست آمده نشان داد که برای بازیابی کامل وزن مخصوص ظاهری، تخلخل و مقاومت به نفوذ، مدت زمان بیشتر از 20 سال نیاز است.

کلیدواژه‌ها

عنوان مقاله [English]

Soil bulk density, porosity and penetration resistance recovery following timber harvest cessation on abandoned skid trails after 20 years, Kheyroud forest

نویسندگان [English]

  • Hadi Sohrabi 1
  • Meghdad Jourgholami 2
  • Baris Majnounian 3
  • Ghavamoddin Zahedi Amiri 3
  • Sattar Ezzati 4
1 M.Sc. Student of Forest Engineering, Faculty of Natural Resources, University of Tehran, Karaj, Iran
2 Associate Prof., Department of Forestry and Forest Economics, Faculty of Natural Resources, University of Tehran, Karaj, Iran.‎
3 Prof., Department of Forestry and Forest Economics, Faculty of Natural Resources, University of ‎Tehran, Karaj, Iran
4 Ph.D. Student, Faculty of Natural Resources and Marine Sciences, Tarbiat Modares University, Noor, Iran
چکیده [English]

     Deforestation and soil degradation start simultaneously, thus the conservation of forest and soil mutually affect each other.  Therefore, techniques should be developed to reduce the amount of forest damage which in turn shortens the recovery time. This study was conducted in two districts of Patom and Namkhaneh located in Kheyroud experimental forest, with the aim to assess the environmental impact of slope, traffic and rutting location on soil physical properties and its recovery over a 20-year period. Fourabandoned, downward skid trails of different ages were selected. In each skid trail, three traffic classes each divided into two slope classes were determined. For measurement of soil bulk density and total porosity, a sample plot of 10×4 m was established on each treatment. The results showed the maximum value of the bulk density and penetration resistance to be associated with high traffic intensity and > 20% slopes. Furthermore, soil bulk densities in different skid trails directions older than 20 years were more than those on the control treatment, yet the difference was not significant. However, the difference in resistance to penetration was significant. Over 20 years of skidding operations, soil physical properties have been retrieved, so that the bulk density and penetration resistance were 12.75 and 23.3% more than those in control area. Whereas this difference was not significant for bulk density, it showed significance for penetration resistance.

کلیدواژه‌ها [English]

  • Soil properties recovery
  • Porosity
  • skid trail
  • Penetration resistance
  • soil bulk density

مراجع

- Alban, H.D., Host, G.E., Elioff, J.D. and Shadis, D.A., 1994. Soil and vegetation response to soil compaction and forest floor removal after aspen harvesting. USDA Forest Service, Research Paper NC-315, St.Paul, Minnesota, 38p.
- Ampoorter, E., Goris, R., Cornelis, WM. and Verheyen, K., 2007. Impact of mechanized logging on compaction status of sandy forest soils. Forest Ecology and Management, 241: 162-174.
- Ampoorter, E., Van Nevel, L., De Vos, B., Hermy, M. and Verheyen, K., 2010. Assessing the effects of initial  soil  characteristics,  machine  mass  and  traffic  intensity  on  forest  soil compaction. Forest Ecology and Management, 260: 1664-1676.
- Anonymous, 1998. USDA Forest Service Manual, FSM 2520 (Watershed Protection and Management) R-6. Supplement No. 2500-98-1, Effective August 24, 16p.
- Aust, W.M., Burger, J.A., Carter, E.A., Preston, D.P. and Patterson, S.C., 1998. Visually determined soil disturbance classes used as indices of forest harvesting disturbance. Southern Journal of Applied Forestry, 22: 245-250.
- Ballard, T.M., 2000. Impacts of forest management on northern forest soils. Forest Ecology and Management, 133: 37-42.
- Benthaus, M. and Matthies, D., 1993. Regeneration befahrener Waldböden. Allgemeine Forstzeitschrift, 48: 448-451.
- Blouin, V.M., Schmidt, M., Bulmer, C.E. and Krzic, M., 2005. Mechanical disturbance impacts on soil properties and lodgepole pine growth in British Columbia’s central interior. Candaian Journal of Soil Science, 85: 681-691.
- Bolding, M.C., Kellogg, L.D. and Davis, C.T., 2009. Soil compaction and visual disturbance following an integrated mechanical forest fuel reduction operation in southwest Oregon. International Journal of Forest Engineering, 20(2): 47-56.
- Boström, U., 1986. The effect of soil compaction on earthworms (Lumbricidae) in a heavy clay soil. Swedish Journal of Agricultural Research, 16: 137-141.
- Crock, J., Hairsine, P. and Fogarty, P., 2001. Soil recovery from track construction and harvesting changes in surface infiltration, Erosion and Delivery Rates with Time. Forest Ecology and Management, 143: 3-12.
- Ezzati, S., Najafi, A., Rab, M.A. and Zenner, E., 2012. Recovery of soil bulk density, porosity and rutting from ground skidding over a 20-year period after timber harvesting in Iran. Silva Fennica, 45(4): 521-538.
- Gomez, A., Powers, R.F., Singer, MG. and Hrowath, W.R., 2002. Soil compaction effects on growth of young ponderosa pine following litter removal in Californias Sierra Nevada. Soil Science Society of America Journal, 66: 1334-1343.
- Greacen, E.L. and Sands, R., 1980. Compaction of forest soils, A review. Australian Journal of Soil Research, 18: 163-189.
- Han, S.K., Han, H.S., Page-Dumroese, D.S. and Johnson, L.R., 2009. Soil compaction associated with cut-to-length and whole-tree harvesting of a coniferous forest. Canadian Journal of Forest Research, 39: 976-989.
- Heilman, P,. 1981. Root penetration of Douglas-fir seedlings into compacted soil.  Forest Science, 27: 660-666.
- Jordan, D., Ponder, F.J. and Hubbard, V.C., 2003. Effects of soil compaction, forest leaf litter and nitrogen fertilizer on two oak species and microbial activity. Applied Soil Ecology, 23: 33-41.
- Kozlowski, T.T., 1999. Soil compaction and growth of woody plants. Scandinavian Journal of Forest Research, 14: 596-619.
- Mohammadi, Z., Naghdi, R., Akef, M., Bagheri, I. and Sayadi, A., 2012. Natural recovery assessment of some physical properties of forest soil compacted by ground base skidding. Iranian Journal of Forest and Poplar Research, 20(3): 472-480 (In Persian).
- Nugent, C., Kanali, C., Owende, P.M.O., Nieuwenhuis, M. and Ward, S., 2003. Characteristic site disturbance due to harvesting and extraction machinery traffic on sensitive forest sites with peat soils. Forest Ecology and Management, 180: 85-98.
- Rab, M.A., 2004. Recovery of soil physical properties from compaction and soil profile disturbance caused by logging of native forest in Victorian central highlands, Australia. Forest Ecology and Management, 191: 329-340.
- Rab, M.A., Anderson, H., Boddington, D. and Van Rees, H., 1992. Soil disturbance and compaction. In: Squire, R.O. (Ed.), First Interim Report for the Value Adding Utilization System Trial. Department of Conservation and Environment, Victoria, Australia, pp. 25-31.
- Roberts, M.R. and Zhu, L., 2002. Early response of the herbaceous layer to harvesting in a mixed coniferous-deciduous forest in New Brunswick, Canada. Forest Ecology and Management, 155: 17-31.
- Shoulders, E. and Terry, T.A., 1978. Dealing with site Disturbances from Harvesting and Site Preparation in the Lower Coastal Plain. In: Proceedings of the Symposium on Principles of Maintaining Productivity on Prepared Sites. Mississippi State University, USA, 126-138.
- Simcock, R.C., Parfitt, R.L., Skinner, M.F., Dando, J. and Graham, J.D., 2006. The effects of soil compaction and fertilizer application on the establishment and growth of Pinus radiata. Canadian Journal of Forest Research, 36: 1077-1086.
- Tiarks A.E., Buford, M.A., Powers, R.F., Ragus, J.F., Page-Dumroese, D.S., Ponder, F.J. and Stone, D.M., 1997. North-American long-term soil productivity research program. Proceedings of the National Silviculture Workshop, Warren, Pennsylvania: 140-147.
- Wang, J., LeDoux, C.B. and Edwards, P., 2007. Changes in soil bulk density resulting from construction and conventional cable skidding using preplanned skid trails. Northern Journal of Applied Forestry, 24(1): 5-8.
- Zenner, E.K., Fauskee, J.T., Berger, A.L. and Puettmann, K.J., 2007. Impacts of skidding traffic intensity on soil disturbance, soil recovery, and aspen regeneration in North Central Minnesota. Northern Journal of Applied Forestry, 24(3): 177-183.
- Zenner, E.K. and Berger, A.L., 2008. Influence of skidder traffic and canopy removal intensities on the ground flora in a clearcut-reserves northern hardwood stand in Minnesota, USA. Forest Ecology and Management, 256: 1785-1794.

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