دوماه نامه

نوع مقاله : مقالات پژوهشی

نویسندگان

1 دانشگاه شهرکرد

2 دانشگاه رامین اهواز

چکیده

پژوهش حاضر به منظور بررسی تاثیر آتش‌سوزی بر میزان فرسایش پاشمانی و برخی ویژگیهای وابسته به فرسایش خاک در مناطقی که طی سال‌های 1387، 1388، 1389 و 1390 در مراتع کرسنک دچار آتش‌سوزی شده‌اند، انجام گردیده است. نمونه برداری در سال 1391 انجام و از هر منطقه 16 نمونه (8 نمونه از منطقه سوخته شده و 8 نمونه به عنوان شاهد) از عمق 7-0 سانتی متری برداشته شد. فرسایش پاشمانی در 2 شیب 9 و 46 درصد با شدت بارش 2 میلی متر بر دقیقه با استفاده از کاسه پاشمان چند متغیره اندازه‌گیری شد. تجزیه و تحلیل آماری داده ها توسط آزمون t مستقل در سطح 5 درصد انجام شد. نتایج نشان داد که خاک پاشمان شده در مناطق سوخته ‌شده افزایش معنی‌دار در تیمار 1 سال پس از آتش سوزی در هر دو شیب 9 و 46 درصد و همچنین در تیمار 2 سال پس از آتش سوزی در شیب 46 درصد داشت. سایر ویژگی های اندازه‌گیری شده نیز (بجز کربنات کلسیم معادل) تحت تاثیر آتش‌سوزی قرار گرفته بود. همچنین بسیاری از ویژگی‌ها تنها در 2 سال اول پس از آتش‌سوزی دارای اختلاف معنی‌دار با مناطق شاهد بوده اند ولی در سال‌های سوم و چهارم پس از آتش‌سوزی به شرایط اولیه خود نزدیک گردیده اند.

کلیدواژه‌ها

عنوان مقاله [English]

Effects of Fire on Soil Splash Erosion in Semi-steppe Rangelandof Karsanak Region,Chaharmahal and Bakhtiari

نویسندگان [English]

  • D. Baharlooi 1
  • S. Ghorbani Dashtaki 1
  • B. Khalil Moghadam 2
  • Mahdi Naderi 1
  • P. Tahmasebi 1

1 Shahrekord University

2 Ahvaz University

چکیده [English]

Introduction: The detachment process can be conceptually divided in two sub-processes included aggregate breakdown (Le Bissonnais, 1996) and movement initiation of breakdown products(Kinnell, 2005). soil detachment depends on raindrop size and mass(Elison, 1944; Bisal, 1960), drop velocity(Elison, 1944; Bisal, 1960), intensity rainfall (Ting et al, 2008), kinetic energy (Kinnell, 2003; Fernandez- Raga et al, 2010), runoff depth(Torri et al, 1987; Kinnell,1991 and 2005), crop covers(Bancy, 1994; Ghahremani et al, 2011), wind speed( Erpul et al, 2000) and experimental area (cup size) (Leguedois et al, 2005; Luk, 1979; Torri and poesen, 1988). Many of studies have been conducted to evaluate the relationship between splash and slope (Bryan, 1979; Torri and Poesen, 1992; Wan et al, 1996).Torri and Poesen (1992) expressed that in steep slope the gravity force adds to the drop detaching force and decreases of soil resistance, consequently increases splash erosion rate with increasing slope. Soil splash erosion is also strongly influenced by soil properties including soil particles size distribution (Mazurak and Mosher, 1968; Legout et al, 2005; fan and li, 1993), soil shear strength(Cruse and Larson, 1977; Al-Durrah and Bradford,1981; Ekwue and ohi; 1990 ), soil cohesion(Torri et al, 1987), soil organic matter content and aggregate size (Ekwue and Maiduguri, 1991; Qinjuan et al, 2008), soil aggregates stability(Qinjuan et al, 2008), surface crust (Qinjuan et al, 2008).
Fire, play an important role in splash erosion. The absence of vegetation cover in disturbed lands accelerates splash erosion rates by as much as several folds compared to undisturbed sites (Lal, 2001; Thomaz and luiz, 2012).The detachment of soil particles by splash depends on several raindrop characteristics, including raindrop size and mass, drop velocity, kinetic energy, and water drop impact angle (Sharma et al., 1993; Singer and Le Bissonnais, 1998; Cruse et al., 2000, Bhattacharyya et al., 2010). Detachment rate is strongly influenced by soil properties, including soil texture and thickness of the water layer at the soil surface (De Ploey and Savat, 1968; Moss and Green, 1983; Sharma et al., 1991; Kinnell, 1991, Jomaa et al., 2010), soil strength, bulk density, cohesion, soil organic matter content, moisture content, infiltration capacity (Nearing et al., 1988; Owoputi, 1994; Morgan et al., 1998, Planchon et al., 2000, Ghahramani et al., 2011), soil initial water content, surface compaction and roughness (Planchon et al., 2000), the nature of soil aggregates and crust, porosity, capacity of ionic interchange, and clay content (Poesen and Torri, 1988). Several studies have shown that splash detachment rate is mainly related to surface rock fragments in soils with sparse vegetation cover (Jomaa et al., 2012). The present study was conducted to investigate the effects of fire on splash erosion and some erosion depended properties in semi-steppe rangeland of Karsanak region in Chaharmahal and Bakhtiari province which affected by man-made fire during 2008, 2009, 2010 and 2011.
Materials and Methods: Soil samples were obtained on 2012 from the mentioned regions (8 samplesfrom the burned area and 8 samples as a control (unburned) in the adjacent burned area) from 0-7 cm depth. Splash erosion under simulated rainfall intensity of 2 mm per minute was measured using multivariate splash cup apparatus considering the slope of 5 and 25 degree. Soil pH, soil electrical conductivity, equivalent calcium carbonate, soil organic matter, sand size fraction particulate organic matter (SSF POM), mean weight diameter and, geometric mean diameter of aggregates, percent of macro and micro-aggregates, percent of clay, silt, sand, water dispersible clay and soil bulk density were measured. Statistical data analysis was performed by t-test at 5% level.
Results Discussion: The results showed that soil splashing increased significantly in treatment 1 year after the fire in both slope 5 and 25 degree and in treatment 2 year after the fire in slope 25 degree. The amounts of increase in soil splashing compared to control treatment were 22, 24 and 15 percent in treatment 1 year after fire in slope 5 and 25 degree and in treatment 2 years after the fire in slope of 25 degree respectively. Comparison of the total soil splash on slopes of 25 degree at 1, 2, 3 and 4 years after the fire, showed a significant increase in the level of five percent relative to the slope of 5 degree at 1, 2, 3 and 4 years after the fire. The other measured soil properties (except equivalent calcium carbonate) was affected by fire. Also, the differences between many of the mentioned properties in the first 2 years after the fire was significant compared with the control area, but they have been reached to the initial values in the third and fourth years after the fire.
Conclusion: Time was shown to be effective factor inrecovering soil propertiesin Karsanak region of Chaharmahal and Bakhtiari province which affected by man-made fire during 2008, 2009, 2010 and 2011. Fire accelerates splash erosion rates by as much as several folds compared to control in this area.

کلیدواژه‌ها [English]

  • Rangelands
  • Splash Erosion
  • Soil properties
1- Sharifi J., and Imani A. 2006. Effect of fire on vegetation and species composition changes in rangeland Stjepan Ardebil. Iranian Journal of Natural Resources. 59: 517-526 (in Persian).
2- Haj Abbasi M. A. 2007. Soil physical properties. Isfahan University of technology. (in Persian).
3- Zolfaghari A. A., and Haj Abbasi M. A. 2008. The impact of land use changes on soil physical properties and hydrophobicity of fereydoun shahr and meadows and forests Lordegan. Journal of soil and Water (Agriculture Science and technology). 22: 251-262 (in Persian).
4- Moghadam M. R. 2007. Ecology of plants. Tehran University. Tehran. (in Persian).
5- Badia D., and Marti C. 2003. Plant ash and heat intensity effects on chemical and physical properties of two contrasting soils. Arid Land Res. Manage, 17: 23-41.
6- Bhattacharyya R., Fullen M.A., Davies K., and C.A. Booth. 2010. Use of palm-mat geotextiles for rainsplash erosion control. Geomorphology, 119: 52–61.
7- Blake G.R., and Hartge K.H. 1986. Bulk density, P 363-375. In: A. Klute. (ed.) Methods of Soil Analysis, Part 1, 2nd ed, ASA, Madison, Wisconsin, USA.
8- Burch G.J., Moor J.D., and Burns J. 1989. Soil hydrophobic effects on infiltration and catchment runoff. Hydrol. Processes, 3: 222-230.
9- Cambardella C.A., and Elliott E.T., 1993. Methods for physical separation andcharacterization of soil organic matter fractions. Geoderma, 56: 449-457.
10- Campbell G.S., Jungbauer J.D.Jr., Bristow K.L., and Hungerford R.D. 1995. Soil temperature and water content beneath a surface. Soil Science, 159 (1): 363-374.
11- Campo J., Andreu V., Gimeno-Garcia E., Gonzalez-Pelayo O., and Rubio J.L. 2008. Medium Term Evolution of Soil Aggregate Stability, Organic Matter and Calcium Carbonate of a Mediterranean Soil Burned with Different intensities, PP. 330-344. In: C. Dais and E. Costantini (Eds). Advances in GeoEcology, 39. Catena Verlag, Reiskirchen.
12- Carleton S.W., and Loftin S.R. 2000. Response of 2 semiarid grasslands to cool-season prescribed fire. J. Range Manage, 53:52-61
13- Celik I. 2005. Land-use effects on organic matter and physical properties of soil in a southern Mediterranean highland of Turkey. Soil and Tillage Research, 83: 270-277.
14- De Noni G., Didier B., Jean- Yves L., Yves Le B., and Jean A. 2002. Proposal of soil indicators for spatial analysis of carbon stocks evolution. 17th. WCSS. 14-21 August. Thailand, 1-13.
15- DeBano L.F.1981. Water repellent soils: a state-of-the-art. General Technical Report PSW-46, Forest Service, US Department of Agriculture, Washington, DC, 21 pp.
16- Ekwue E.I., and Maidugury. 1991. The effects of soil organic matter content. Rainfall duration and aggregate size on soil detachment. Soil Technol. 4: 197-207.
17- Gee G.W., and Bauder J.W. 1986. Particle Size Analysis, P 383-411. In: A. Klute. (ed.) Methods of Soil Analysis, ASA and SSSA, Madison, Winsconsin, USA.
18- Gillon D., Gomendy V., Houssard C., Marechal J., and Valette J.C. 1995. Combustion and nutrient losses during laboratory burns. International Journal Wildland Fire, 5 (1): 1-12.
19- Giovannini G., and Sequi P. 1976. Iron and aluminium as cementing substances of soil aggregates. I. Acetylac etone in benzene as an extractant of fractions of soil iron and aluminium. Journal of Soil Science, 27: 140-147.
20- Granged A.J.P., Zvala L.M., Antonio J., and Moreno B.G. 2011. Post-fire evolution of soil properties and vegetation cover in a Mediterravean heathland after experimental burning: A 3years study. Geoderma, 164: 85-94.
21- Hartford R.A., and Frandsen W.H. 1992. When it’s hot, it’s hot... or maybe it’s not! (Surface aiming may not portend extensive soil heating). International Journal Wildland Fire, 2 (1): 139-144.
22- Hernandez T., Garcia C., and Reinhard T. 1997. Short-term effect of wildfire on the chemical, biochemical and microbidogical properties of Mediterranean pine forest soils. Biol Fertil. Soil, 25: 109-116.
23- Kettering Q.M., and Bigham J.M. 2000. Soil color as an indicator of slash and burn fire severity and soil fertility in Samatra. Indonesia. Soil. Sci. Soc. Am. J, 64: 1108-1117.
24- Lal R., Hall G.F., and Miller F.P. 1989. Sill degradation: I. Basic process. Land Degradation and Rehabilitation, 1: 51-69.
25- Legout C., Legue´dois S., Le Bissonnais Y., and Malam Issa O. 2005. Splash distance and size distributions for various soils. Geoderma, 124: 279–292.
26- Loeppert R.H. and Sparks, D.L. 1996. Carbonate and gypsum, P 437-475. In: D.L. Sparks. (ed.) Methods of soil analysis, Part 3, chemical method, SSSA, Madison, Winsconsin, USA.
27- Martinez N., Coughlan K., and Cresswell H. 2008. Soil physical measurement and interpretation for land evaluation: (2nded). SBS Publshers and Distributors PVT. LTD, New Delhi, India, 15p.
28- Mbagwu J., and Bazzoffi P. 1998. Soil characteristics related to resistance of breakdown of dry soil aggregates by water-drops. Soil and Tillage Research, 45: 133-145.
29- Morgan J.W., and Lunt I.D. 1999. Effects of time-since-fire on the tussock dynamics of a dominant grass in a temperate Australian grassland. Journal of Biological Conservation. 88: 379-386.
30- Morgan R.P.C. 2007. Field studies of rainsplash erosion. Earth Surf. Process. 3: 295-299.
31- Neff J.C., Harden J.W., and Gleixner G. 2005. Fire effects on soil organic matter content, Composition, and nutrients in boreal interior Alaska. Can J. For. Res, 35: 2178-2187.
32- Providali I., Elsenbeer H., and Conedera M. 2001. Post-fire management and splash erosion in a chestnut coppice in southern Switzerland. Forest Ecology and Management, 162:219-229.
33- Qinjuan CH., Qiangguo C., and Wenjun Ma. 2008. Comparative Study on Rain Splash Erosion of Representative Soils in China. Chin. Geogra. Sci, 18(2):155–161.
34- Rengasamy P., and Aust J. 1984. Dispersion of calcium clay. Soil Res. 20: 7-153.
35- Rhoades J.D. 1996. Salinity: electrical conductivity and total dissolved solids, P 417-436. In: D.L. Sparks. (ed.) Methods of Soil Analysis. Part 3, chemical methods, SSSA, Madison, Winsconsin, USA.
36- Soler M., Sala M., and Gallart F. 1994. Post fire evolution of runoff and erosion during an 18-month period. In: M. Sala and J.L. Rubio (Eds), Soil Erosion as a Consequence of Forest Fires. Geoforma Ediciones, Logrono, pp. 149-161.
37- Ulery A.L., Graham R.C., and Amrhein C. 1993 Wood-ash composition and soil pH following intense burning. Soil Science, 156 (1): 358-364.
CAPTCHA Image