بررسی آستانه‌های توپوگرافیکی وتحلیل نقش نوع سازندهای سطحی در توسعه خندق‌ها در دامنه‌های کوهستان‌های نواحی نیمه خشک مطالعه موردی: حوضه شورچای

نوع مقاله: مقاله پژوهشی

نویسندگان

1 دانشیار ژئومورفولوژی، دانشگاه تبریز، تبریز، ایران

2 استادیار ژئومورفولوژی، دانشگاه تبریز، تبریز، ایران

چکیده

در سطوح دامنه‌های مناطق
نیمه خشک انواع فرسایش و با شدت‌های متفاوت فعال است. فرسایش خطی بویژه فرسایش
خندقی در بین انواع فرسایش مهمترین عامل تخلیه و ورود مواد دامنه ای به دشت‌های
سیلابی وآب‌های جاری محسوب می‌شود. این نوع فرسایش در محدوده‌های کوهستانی نواحی
نیمه خشک که دامنه‌هابه خوبی توسط پوشش گیاهی محافظت نمی‌شوند، بیشتر دیده می‌شود.
در تشدید فرسایش عوامل مختلفی دخیل هستند، اما سرعت تشکیل عوامل مختلفی دخیل از
پدیده‌های مربوط به فرسایش، به ویژه خندق‌ها در سطوح شیبدار متشکل از سازندهای
سطحی مستعد به فرسایش خطی قابل ملاحظه است. در حوضه شورچای واقع در دامنه‌های شرقی
کوهستان سهند (واقع در موقعیت جغرافیایی از
́ 05˚ 36 تا́ 20 ˚37 عرض
شمالی واز
́ 43 ˚ 46 تا́ 15́˚ 47
طول شرقی )بر روی دامنه‌های متشکل از سازندهای سطحی متشکل از مارن، سیلت و رس حضور
خندق‌های عمیق ودر حال توسعه در بخش‌های مختلف حوضه، بویژه در شیب‌های منتهی به
رودخانه اصلی بیشتر دیده می‌شود. در این مقاله با استفاده از شاخص‌ها وضرایب مختلف
مانند شاخص‌های
V و TCI عوامل تشکیل
وتوسعه این پدیده بررسی و تحلیل شده. نتایج حاصل از این بررسی‌ها نشان می دهد که
در بخش‌های مختلف حوضه شورچای، شیب و نوع سازندهای سطحی دامنه‌ها نقش اولیه را در
فراهم نمودن زمینه لازم برای تشکیل خندق‌ها ایفا نموده است. تحلیل مقادیر حاصل از
به کارگیری شاخص‌ها در بخش‌هایی از محدوده مورد مطالعه نشان می دهد که در مواردی
مقادیر حاصل از حد آستانه‌ها تجاوز نموده است، که این امر از پتانسیل بالای دامنه‌های
محدوده مذکور برای فرسایش خطی، حکایت می‌کند

کلیدواژه‌ها


عنوان مقاله [English]

Investigation of topographic thresholds and analysing role of surface materials on gully development in the hillslope of semi arid areas.Case study: Shoorchay

نویسندگان [English]

  • M. Bayati Khatibi 1
  • M. Rajabi 1
  • F. Karami 2
چکیده [English]

  Investigation of topographic thresholds and analysing role of surface materials on gully development in the hillslope of semi arid areas.Case study: Shoorchay     M. Bayati Khatibi. ( * ),   Associate Professor of Geomorphology, university of Tabriz, Tabriz, Iran.   e mail: m_bayati@tabrizu.ac.ir     M. Rajabi.   Associate Professor of Geomorphology, university of Tabriz, Tabriz, Iran.     F. Karami.  Assistant Professor of Geomorphology, university of Tabriz, Tabriz, Iran.   Received: 21 Desember 2009 / Accepted: 17 August 2010, 5-8 P     Extended abstract   1- Introduction   In the surface of semiarid regions, erotion accures severe and rapidly. Liner erosion, specially gully erosion –as a hazardous erosion type ,is important factor for delivery materials into runoff and flood plains. This erosion type is formed in semi arid mountains that is not covered by plants. In intensive erosion, many factors are interference, but magnetude of erosion on suitable materials or erosible materials is very high. In shoorchay catchement on Eastern slope of Sahand (located from 36˚ 05́ to37˚ 20́ N and from 46˚ 42́ to 47˚ 15́ E)     Big gully is developed on the hillslope of silt and clay. In this article have been effects of factors on studied gully formation and development many indices, such as V and TCI. The results of this study show that in many parts of Shorchay Basin, slope and surface materials have important role on development of gullies.     2- Metodology   In this article, was investigated linear erosion factors by V and TCI indices. River gradient, flow velocity, time concentration and power erosion of rivers, have been studied and computed as creation and development factors. TC (time concentration) was related to physiographic characteristics, eg., surface property, shape of basin, lengh and slope of reaches, relief, type of plant covers, soil texture. Therefore these factors were presented erosion potential of basin. TC was estemited using Willimas methods. Rn, C, T, FN indices have been used in this study, as morphometery indices.   3- Discussion   In the shoorchy as a sub basin of Garangoo Basin, rate of sediment is very high. Unstable materials, unstable slope on course of river,unprotect slope and salt dom which don’t have suitable plant covers, are main causes of intensive erosion in Shoorchay basin. In the gentle parts of basin, erosion is higher than slope. Mentioned site of basin, in spite of presence sustainble materials on surfaces, rate of erosion is low. These land are farmlands.     4- Conclusion   The rate of TCI is high in Northern and Western part of Shoorchay Catchement. these results also were sugessted that these sites have very high potential for gulling processes. In most site of Shoorchay catchement, when lengh of slope is increasing, the rate of TCI also is increasing. This result show affect of gathering water on erosion. The rate of V at up parts of catchement was high and was decreasing in the midle and down parts of catchement. Most of gullies were made and developed on the sites with marn and silt. Results showed that V and TCI were not conformed in many parts of catchement. The analysis of used indices in many parts of study area showed that numurical data were higher than limit of thresholds .These results show that potential of slope for liner erosion is high   Key words : liner erosion, gully erosion, topographical factors, surface materials eastern slope of Sahand muntain.       References   Amsler, L. M., C, G. Ramonell & H, A. Toniolo. (2005). Morphologic changes in the Parana river channel in the li ght of the climate variability during the 20the century, Geomorphology, 65, p 56-70.   Battagli, S. a., L. Leoni & F. Sartori. (2002). Mineralogical and grain size composition of clays developing calanchi and biancane erosional landforms,Geomorphology, 49, 153–170 .   Boardman, J., A. J. Parsons & R. Holland., P. J. Holmes, Washington. (2003). Development of badlands and gullies in the Sneeuberg, Great Karoo, South Africa, Catena, 50, 165– 184.   Casalı, J., J. Loizu, M.. Campo, L.. De Santisteban & J. A´ lvarez-Mozos. (2006). Accuracy of methods for field assessment of rill and ephemeral gully erosion, Catena, 67, 128 – 138 .   Casasnovas, J.A. Martı´nez. (2003). A spatial information technology approach for the mapping and quantification of gully erosion, Catena, 50, 293– 308.   Casasnovas, J. A. Mart´ınez., M. C. Ramos & M. Ribes-Dasi. (2002). Soil erosion caused by extreme rainfall events: mapping and quantification in agricultural plots from very detailed digital elevation models, Geoderma, 105, 125–140.   Chaplot, V., E. Coadou le Brozec, N. Silvera & C. Valentin. (2005). Spatial and temporal assessment of linear erosion in catchments under sloping lands of northern Laos, Catena, 63, 167–184,   Company of Regional Water, Easthern Azarbayjan. (1384). Soil study at down parts of Khoram DArag Dam.   Elsen, Erik van den., Yun Xie., Baoyuan Liu., Jannes Stolte., Yonqui Wu., Kim Trouwborst and Coen J. Ritsema. (2003). Intensive water content and discharge measurement system in a hillslope gully in China, Catena, 54, 93–115 115.   Gabet, Emmanuel J. & Andy Bookter. (2008). A morphometric analysis of gullies scoured by post-fire progressively bulked debris flows in southwest, Montana, USA, Geomorphology, 96 298–309.   Govers, G.2007. Rill erosion .Earth science review.84, p87-102.   Gyssels, G., J. Poesen, J. Nachtergaele & G. Govers. (2002). The impact of sowing density of small grains on rill and ephemeral gully erosion in concentrated flow zones., Soil & Tillage Research, 64 ,189–201.   James, L. Allan., Darrell Glen Watson & William F. Hansen. (2007). Using LiDAR data to map gullies and headwater streams under forest canopy: South Carolina, USA.Catena, 71, 132–144.   Kheir, Rania Bou., Olivier Cerdan & Chadi Abdallah. (2006). Regional soil erosion risk mapping in Lebanon,Geomorphology, 82, 347–359.   Knapen, A., J. Poesen & S. De Baets. (2007). Seasonal variations in soil erosion resistance during concentrated flow for a loess-derived soil under two contrasting tillage practices . soil & Tillage Research, 94, 425–440.   Knapen, A., J. Poesen., G. Govers., G. Gyssels & J. Nachtergaele. (2007). Resistance of soils to concentrated flow erosion: A review ,Earth-Science Reviews, 80, 75–109.   Laaha, G., & G.Bloschl. (2005). Low flow estimates from short stream from flow records a compararison of methods, Journal of Hydrology, 306-286.   Marker, M., Angeli, L., Bottai, L., cCostantini, R. (2008). Assessment of land degradation susceptibility by scenario analysis. Geomorphology, 93, p120-129.   McIntosh, Peter & Mike Laffan . (2005). Soil erodibility and erosion hazard: Extending these cornerstone soil conservation oncepts to headwater streams in the forestry estate in Tasmania .Forest Ecology and Management 220, 128–139 139.   Pelacani, S., Marker, M & Rodolfi, G. (2008). Simulation of soil erosion and deposition in a changing land use. Geomorphology., 99 p329-340.   Peugeot, S., B. Cappelare., B. E.Vieux., L. Seguis & A. Maia. (2003). Hydrologic process simulation of a semiarid endoreic catchment in Sahelan west ,model-aided data analysis and screening, Journal of Hydrology, 279: 224-243.   Poesen, J., Nachtergaele, G. Verstraeten & C. Valentin. (2003). Gully erosion and environmental change:importance and research needs, Catena, 50, 91– 133.   Rahman, M. (2009). Soil erosion hazard evalution.Ecological modeling. 220, p1724-1734.   Ries, J.B & I. Marzolff. (2003). Monitoring of gully erosion in the Central Ebro Basin by large-scale aerial photography taken from a remotely controlled blimp ,Catena 50, 309– 328.   Sang-Arun. J., M. Mihara, Y. Horaguchi & E. Yamaji. (2006). Soil erosion and participatory remediation strategy for bench terraces in northern Thailand,Catena, 65, 258 – 264 .   Torri, D., J. Poesen. b, L. Borselli and A. Knapen. (2006). Channel width–flow discharge relationships for rills and gullies, Geomorphology, 76, 273–279 .   Valca´rcel, M. M., T. Taboada., A. Paz and J. Dafonte. (2003). Ephemeral gully erosion in northwestern Spain .Catena 50, 199– 216.   Vanacker, Veerle., Gerard Govers., Jean Poesen., Jozef Deckers., Gerd Dercon and George Loaiza. (2003). The impact of environmental change on the intensity and spatial pattern of water erosion in a semi-arid mountainous Andean environment,Decrease of sheet, Catena, 51, 329–347 .   Vandekerckhove, L., J. Poesen., D. Oostwoud Wijdenes., G. Gyssels., L. Beuselinck & E. de Luna. (2000). Characteristics and controlling factors of bank gullies in two semi-arid mediterranean environments,Geomorphology, 33,37–58 .   Vanwalleghem, T., J. Poesen., J. Nachtergaele & G. Verstraeten. (2005). Characteristics, controlling factors and importance of deep gullies under cropland on loess-derived soils./, Geomorphology, 69, 76–91.   Vente, Joris T and, Jean Poesen. (2005). Predicting soil erosion and sediment yield at the basin scale: Scale issues and semi-quantitative models./, Earth-Science Reviews, 71, 95–125.   Yadav, R. (2003). Development of hydrologically optimal and formation practice for gully erosion susceptible soil.Agricultural water management ,59, p 112-135.   ygarden, Lillian. (2003). Rill and gully development during an extreme winter runoff event in Norway, Catena, 50, 217– 242.   Wilkinson, S., Prosser, J. (2009). Modelling and testing spatially distributed sediment buget to relate erosion processes to sediment yields. Environmental modelling and software. 24, p 489-501.   Zhou, P. (2008). Effect of vegetation cover on soil erosion in a mountainous watershed.Catena.75, p 319-325.        

کلیدواژه‌ها [English]

  • liner erosion
  • gully erosion
  • topographical factors
  • surface materials eastern slope of Sahand muntain
concentrated flow for a loess-derived soil under two contrasting tillage practices.soil & Tillage Research , 94, 425–440.

Knapen, A., J. Poesen., G. Govers., G. Gyssels & J. Nachtergaele. (2007). Resistance of soils to concentrated flow erosion: A review ,Earth-Science Reviews, 80, 75–109.

-Laaha, G & G. Bloschl. (2005). Low flow estimates from short stream from flow records a compararison of methods, Journal of Hydrology, 306-286.

Marker, M., Angeli, L., Bottai, L., cCostantini, R. (2008). Assessment of land degradation susceptibility by scenario analysis. Geomorphology, 93, p120-129.

McIntosh, Peter & Mike Laffan. (2005). Soil erodibility and erosion hazard: Extending these cornerstone soil conservation oncepts to headwater streams in the forestry estate in Tasmania .Forest Ecology and Management 220 , 128–139 139.

Pelacani, S., Marker, M & Rodolfi, G. (2008). Simulation of soil erosion and deposition in a changing land use. Geomorphology., 99 p329-340.

Peugeot, S., B. Cappelare., B. E. Vieux., L.Seguis & A. Maia. (2003). Hydrologic process simulation of a semiarid endoreic catchment in Sahelan west ,model-aided data analysis and screening,Journal of Hydrology ,279:224-243.

Poesen, J., Nachtergaele, G. Verstraeten & C. Valentin. (2003). Gully erosion and environmental change:importance and research needs,Catena, 50, 91– 133.

Rahman, M. (2009). Soil erosion hazard evalution.Ecological modeling. 220, p 1724-1734.

Ries, J. B & I. Marzolff. (2003). Monitoring of gully erosion in the Central Ebro Basin by large-scale aerial photography taken from a remotely controlled blimp, Catena 50, 309– 328.

Sang-Arun, J., M. Mihara, Y. Horaguchi & E. Yamaji. (2006). Soil erosion and participatory remediation strategy for bench terraces in northern Thailand, Catena, 65, 258 – 264.

Torri, D., J. Poesen.b, L. Borselli & A. Knapen. (2006). Channel width–flow discharge relationships for rills and gullies, Geomorphology, 76, 273–279.

Valca´rcel, M.M., T. Taboada., A. Paz & J. Dafonte. (2003). Ephemeral gully erosion in northwestern Spain .Catena 50 , 199– 216.

Vanacker, Veerle., Gerard Govers., Jean Poesen., Jozef Deckers.,Gerd Dercon and George Loaiza. (2003). the intensity and spatial pattern of water erosion in a semi-arid mountainous Andean environment,Decrease of sheet, Catena, 51, 329–347 .

Vandekerckhove, L., J. Poesen., D. Oostwoud Wijdenes., G. Gyssels., L. Beuselinck & E. de Luna. (2000). Characteristics and controlling factors of bank gullies in two semi-arid mediterranean environments, Geomorphology, 33, 37–58.

Vanwalleghem., T., J. Poesen., J. Nachtergaele & G. Verstraeten . (2005). Characteristics, controlling factors and importance of deep gullies under cropland on loess-derived soils./, Geomorphology, 69, 76–91 .

Vente, Joris T & Jean Poesen. (2005). Predicting soil erosion and sediment yield at the basin scale:Scale issues and semi-quantitative models./, Earth-Science Reviews, 71 , 95–125.

Yadav, R. (2003). Development of hydrologically optimal and formation practice for gully erosion susceptible soil.Agricultural water management, 59, p 112-135.

ygarden, Lillian. (2003). Rill and gully development during an extreme winter runoff event in Norway,Catena, 50, 217– 242.

Wilkinson, S., Prosser,J. (2009). Modelling and testing spatially distributed sediment buget to relate erosion processes to sediment yields.Environmental modelling and software. 24, p 489-501.

Zhou, P. (2008). Effect of vegetation cover on soil erosion in a mountainous watershed.Catena.75, p 319-325.