اثر حساسیت به فرسایش و کاربری‌ اراضی بر خصوصّیات مورفومتری رسوب بستر (مطالعه موردی: رودخانه وازرود)

نوع مقاله : مقاله پژوهشی


1 دانشکده منابع طبیعی و علوم دریایی دانشگاه تربیت مدرّس، نور، مازندران

2 دانشکده منابع طبیعی و علوم دریایی، دانشگاه تربیت مدرّس، نور، مازندران


        بررسی عوامل مؤثر بر خصوصّیات مورفومتری رسوبات بستر رودخانه­ها می­تواند منجر به درک بهتر فرآیندهای رسوب­گذاری و حمل رسوب و طبعاً مدیریت کارآتر و استفاده بهینه از آنها شود. تحقیق حاضر با هدف بررسی اثرات تغییر حساسیت به فرسایش سازندها، کاربری اراضی و برداشت شن و ماسه بر خصوصّیات مورفومتری رسوبات بستر در مسیری به طول 30 کیلومتر از رودخانه وازرود در استان مازندران انجام گرفت. به­همین منظور تعداد 9 مقطع برای نمونه­برداری در این رودخانه به­گونه­ای تعیین شدند که بتوان این اثرات را بررسی کرد. نمونه رسوبات بستر در این مقاطع با شیوه ترکیبی برداشت و خصوصّیات مورفومتری شامل میانگین، جورشدگی، چولگی، کشیدگی، قطرهای ده، پنجاه و نود درصد، بافت، کرویت و گردشدگی با استفاده از روش الک کردن و نرم افزار GRADISTAT محاسبه گردید. نتایج حاصل از تحقیق نشان داد که تغییر حساسیت به فرسایش سازندها، کاربری مسکونی و برداشت شن و ماسه در این رودخانه روند تغییرات طبیعی پارامترهای اندازه رسوبات (میانگین، 105090d و بافت) و نیز گردشدگی رسوبات بستر رودخانه را تحت تأثیر قرار داده و در برخی مقاطع روند را معکوس نموده­اند.


عنوان مقاله [English]

Effects of Erosion Sensitivity and Different Land Uses on Morphometric Characteristics of Bed Sediments (Case Study: Vazrood River)

نویسندگان [English]

  • A Khaledi Darvishan 1
  • SHR Sadeghi 2
  • L Gholami 2
چکیده [English]

Study of effective factors on morphometric characteristics of bed sediments may lead to better understanding of sediment transportation and deposition processes and finally, their efficient control or optimal utilization. The present study was aimed to evaluate the effects of erosion sensitivity of formations, land use and sand and gravel mining on morphometric characteristics of bed sediments at a 30 km reach of VazroodRiver in Mazandaran Province, Iran. To achieve the study purposes, 9 sampling sections were selected so that the desired effects could be assessed. The bed sediments were then sampled using combining technique and the morphometric characteristics viz. mean, sorting, skewness, kurtosis, d10, d50, , d90, texture, sphericity and roundness were determined using sieving and GRADISTAT software. The results of the study revealed that erosion sensitivity of the formations, residential use and sand and gravel mining in the river all affected the natural trends of the sediments size parameters (mean, d10, d50 and d90 and sediment texture) as well as roundness, and reversed the trend in some sections.

کلیدواژه‌ها [English]

  • Bed sediment
  • Granolumetry
  • Mazandaran
  • Roundness
  • Sediment morphometry
  • Vazrood
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