تحلیل حساسیت روش‌های هیدرولیکی نسبت به روش‌های تأمین اطلاعات هیدروموفولوژیکی برای تعیین نیاز محیط زیستی

نوع مقاله: مقاله پژوهشی

نویسنده

دانشیار گروه مهندسی آب، دانشکده فنی و مهندسی، دانشگاه بین‌المللی امام خمینی (ره)، قزوین

چکیده

در این مقاله به اهمیت استفاده از روش‌های هیدرولیکی در تعیین جریان محیط زیستی پرداخته شد. روش هیدرولیکی برای تعیین نیاز محیط زیستی وابسته به مقاطع عرضی رودخانه است؛ ولی علی‌رغم استفاده گسترده، تاکنون پژوهشی در مورد ضوابط استخراج اطلاعات از این مقاطع صورت نگرفته است. در این پژوهش نشان داده شد که عمق مقاطع عرضی بر روی نتیجه حاصل از روش هیدرولیکی بسیار تأثیر‌گذار است. با در نظر گرفتن ماهی به‌عنوان گونه شاخص زیستگاه، لازم است عمق استخراج اطلاعات از مقطع عرضی به یک متر محدود شود. دومین عامل مهم در این روش، انتخاب میزان افزایش عمق در هر مرحله یعنی y∆ مناسب برای استخراج مشخصات هندسی و هیدرولیکی برای توسعه منحنی دبی- محیط خیس شده است، که در این پژوهش 1 سانتی‌متر به‌دست آمد. میزان عدم قطعیت دبی محیط زیستی محاسبه شده توسط روش هیدرولیکی برای تصمیم‌گیری در مورد تخصیص آب در مناطق پرتنش دارای اهمیت است. ضریب مانینگ یکی از مهم‌ترین عوامل مؤثر در تعیین جریان رودخانه است. با مطالعه انجام شده در محدوده‌ای معادل سه برابر انحراف از معیار ضریب مانینگ برای منطقه مطالعاتی ثابت شد که تأثیر این ضریب در تعیین دبی محیط زیستی در مقابل تخمین دبی رودخانه بسیار کمتر است.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Sensitivity Analysis of Hydraulic Methods Regarding Hydromorphologic Data Derivation Methods to Determine Environmental Water Requirements

نویسنده [English]

  • Alireza Shokoohi
Associate professor- Water engineering department- Faculty of technical and engineering- International University of Imam Khomeini
چکیده [English]

This paper studies the accuracy of hydraulic methods in determining environmental flow requirements. Despite the vital importance of deriving river cross sectional data for hydraulic methods, few studies have focused on the criteria for deriving this data. The present study shows that the depth of cross section has a meaningful effect on the results obtained from hydraulic methods and that, considering fish as the index species for river habitat analysis, an optimum depth of 1 m should be assumed for deriving information from cross sections. The second important parameter required for extracting the geometric and hydraulic properties of rivers is the selection of an appropriate depth increment; ∆y. In the present research, this parameter was found to be equal to 1 cm. The uncertainty of the environmental discharge evaluation, when allocating water in areas with water scarcity, should be kept as low as possible. The Manning friction coefficient (n) is an important factor in river discharge calculation. Using a range of "n" equal to 3 times the standard deviation for the study area, it is shown that the influence of friction coefficient on the estimation of environmental flow is much less than that on the calculation of river discharge.

کلیدواژه‌ها [English]

  • Environmental flow
  • Hydraulic Method
  • Maximum Curvature
  • Sensitivity and Uncertainty Analysis

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