شاخص های مبتنی بر منحنی تداوم جریان و Low flow indices

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۳ otters ‏تست‎ شاخص های مبتنی بر منحنی تداوم جریان و ‎LOW FLOW INDICES‏ آذرماه ۹۸ 

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Low Flow Indices: 

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شاخمرهایستنیبر منحنی دلوم جر بان. 1 ‎FLOW DURATION CURVE INDEXES‏ 

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رح كود * ,126 "آمجموعه کاملیاز مقادیر دبی‌رودخانه ه از جریانکمینه تا رویدادهای‌سیابیرا در بردلشته و دیصد زمانی‌ک هه دبی‌مدنظر طی یکدوید خاص بولبر یا بیشتر لستوا ارلئه میکند لینمنحنی‌ها در طیفوسیعیاز مطا-ات‌هیدراوژیکی‌مورد لستفاده قرار میگیرند زیرا لطاهاتبا ارزش و ضروریدر ارتباط با ویژگی‌های‌جریازو تغییولتلندر لختیار داشته و معرفيفتار و پاسخ حوزه میاشند نخستین مطالعة جامع بر روی منحنی تداوم جریان را سارسی, در سال ۱۹۵۹ میلادی, انجام داد. منحنی تداوم جریان (۴06) یکی از روش های ارزنده است با اطلاعلتی مفید که همه دبی های رودخانه اعم از کم و جریان سیلابی را نمایش می دهد. این منحنی رابطة بین مقادیر دی و درصد زملنی را که این دبی مساوی یا بیشتر از آن است به نمایش می گذارد. به عبارت دیگر. رابطة بين بزرگی و فراولئی دبی رودخنه را نشان می دهد. برای رسم منحنی تداوم جریان. نخست دبی هاي هر ایستگاه را.به صورت نزولی, مرتب می کنیم و روی محور ها نملیش می دهیم و در محور 6(ها احتمال وقوع تجربی آن را كه از فرمول تجربى ويبول به دست مى آيدء نمليش مى دهيم. از لن براى مقایسه رزيم جريان حوزه هاى مورد استفاده قرار مى كيرد. شكل منحنى نيز انعكاسى از تأثير يارامترهاى لب و هوايى و فيزيوكرافى بر جريان رودخلنه و ياسخ هيدرولوزيكى حوزه / 

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تعریف + Flow duration curve is a plot of discharge versus percentage of time for which the discharge is available. It is obtained from hydrograph data. The flow or discharge can be Flow Duration Curve expressed as cubic meters per second, per week or other unit of time. If the head at which the flow is available is known, the discharge can be calculated in terms of the kilowatts power (P) using following equation, P=(0.736/75)"Qphn kW + The flow duration curve becomes the load duration curve for hydroelectric plant and thus it is possible to know the total power available at the site. The maximum and minimum conditions of flow can also be obtained by the flow duration curve where minimum flow condition decides the maximum capacity of plant that can be improved by increasing the storage capacity. Figure shows that flow duration curves are of ne use where the time sequence of the flow is of importance such as in the study of floods. 

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SA 5 ۳4 ‏تعر یف‎ * The flow-duration curve is a cumulative frequency curve that show the percent of time specified discharges were equaled or exceeded during a given period. ‘Mean daily flows * It combines in one curve the flow characteristics of a stream ees throughout the range of discharge, without regard to the Mean annual flows sequence of occurrence. + If the period upon which the curve is based represents the Flow rate Q(cumec) os BS 8 2 8 long-term flow of a stream, the curve may be used to predict the distribution of future flows for waterpower, water-supply, and pollution studies. 

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كاربرد کاربردها : * انرژی برق آبی و طراحی سامانه های آبی * مدیریت آلودگی در رودخانه و رسوبگذاری و فرسایش sew ‏ع‎ a 0 * 1 i. 5 1 . 2 0 Ss ‏برنامه ریزی منلبع لب. از جمله تأمین لب شرب. کشاورزی. پرورش ماهی و( تحقیقات‎ * مرتبط با حفاظت از اکوسیستم * کالیبراسیون مدلهای هیدرولوژیکی- درخصوص مرتفع کرد:, مشکلات ناشم, از عدم قطعیت داده ها و تفاوت حساسيت به اندازه داده هاى مورد استفاده **ارائة مدل منحنى_ تدا بان حوزه هاى فاقد آما 

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Flow Duratipn Curve Seasonal Indexes (FDCSI) كاربرد تآثير بارامترهاى هندسى و هيدرولوزيكى حوزه بر شكل منحنى تداوم جريان: ‎ws OL 5‏ صورت تجریی است و در دو دسته گرافیکی وآماری قراز دارد" روش گرافیکی. برروی تأثیر مشخصه های فیزیوگرافیک و ب و هولئی بر شکل منحنی تداوم جریان تمرکز دارند. روش های آماری بر روی توزیع های آماری. برای برازش به منحنی تداوم جریان و ارتباط اين برازش ها به مشخصه های فیزیکی حوزه متم رکزهستند. مطالعات كرافيكي: يارامترهاى متحدد فيزيوكرافيكى و اقلیمی را در شکل منحنی موثر دانسته انده از جمله: نقش خاک و زمین شناسی . نقش گیاهی, تغییرات کاربری | ‎a‏ بوشش كياهى. هر روش ‎base) Gin‏ 7 متسدد تزاف برازشن جف شكل سعجنی تناوم حریان به كار بده قده اه که از جمله آنهاء کاربرد توزیعهای احتمالاتی به کار رفته مانند توزیع لوگ نرمال, توزیع گاماء توزيغ بثا واتوزيغ لجساتيك ممياد 4 

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10 كاربرد 5 .Water quality (Quality-of-water 1. Water resource manage ae 0 studies) 2.Public water supply 1 shee 6. Hydropow “* 3. Agriculture 2 power(Water ۳ ۱ PRS FDCs forthe sumer season oe te) and ner season (old te for Flsa at Enappom in ‏مود‎ 4. Fish farming 7.Navigation 8. Ecosystem protection and amenities 9.Studying the effect of geology on low 

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11 < ae ‏معرفی نرم افزار‎ #فایل اکسل مایکرو نویسی شده برای رسم نمودار ‎FDC‏ # نرم افزار مورد استفاده: ‎https s/hydrooffice.org/TOOWFDC‏ لستفاده از نرم لفزا ۴ ۰ ۲۴۱۵۷/56۲۵۵۲۲ ۴۵۱۵96 

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12 معرفی نرم افزار فایل اکسل مایکرو نویسی شده پرای رسم نمودار ۴06 [The purpose ofthis program is to determine the food duration curves for a ivan data set using tha Mathod of Moments and the Weibull mathod [Input tho flow rates inthe yallow Boxes in any order without zero values, 12. Select whether the values are daily lows or annual peaks 8. Click the Cafculate fow-duration curves button and view output, Annus Peake | ||Calculate flow-duration curves View Flow-Duration Curve 

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معرفی نرم افزار bp. alpha 14747 2 30 1 2 13.3056 | es | 8 Average of x2 35 087 ‘Annual Retum Period 100 75.4200 #فایل اکسل مایکرو نویسی شده برای رسم نمودار ‎FDC‏ ‘Average oF ۳۰۵ 2:۳7 0 ۳13 3 | 0475003[ 2 76.2588 13 

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14 معرفی نرم افزار #فايل اكسل مايكرو نويسى شده پرای رسم نمودار ۴06 = Flow-Duration Curve Flow Duration Curve ‏سپ جع‎ as Es ‏دبس‎ 0 

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15 معر ی فر م افز از نرم افزار مورد استفاده: ‎https://hydrooffice.org/Tool/FDC‏ زاری است که امکان محاسبه و ارائه منحنی های تداوم جریان را فراهم می آورد. به عنوان مثال + اين منحنی ها اغلب در ارزیایی خشکسالی هیدرولوژیکی استفاده می شوند. منحنی های تداوم جریان می تولند برای داده های ایستگاه های هیدرومتری بصورت سالانه يا ماهانه و روزانه و همچنین براساس طول دوره آماری و یا دوره آماری مشترک, ایجاد شود. + A tool from the older generation that allows calculating and rendering + The aim of that software is to increase our understanding of flow regimes, of duration curves. For example, these curves are often used in the _linkages to other physical processes, the combined influence on ecological assessment of hydrological drought. function, and the result of altering these processes on the integrity of river systems. + Duration curves can be created from the entire imported time series ‎We are interested in methods to identify and quantify ecologically-important‏ + يوادم اه و و دا هام67 مس ی ‎‘components of flow regimes, assess their alteration through time with respect ‎‘Ti 2. els cai Fa ilo ho ation cue to a reference condition, and relate hydrological alteration to changes in ‎Into the module can be imported dally or weekly types of time series. ‏جوع سواه‎ ‎In adgition to discharge time series can be for the calculation and 3 + We are also interested in using this information to characterize and classify ‎analysis used variable time series of a continuous measurements, ‎‘both natural and altered flow regimes. Thus the analyses and related methods which are used in hydrology and hydrogeology. in SAAS reflect a focus on environmental flow assessments. ‎ 

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16 معر ی فر م افز از نرم افزار مورد استفاده: ‎https://hydrooffice.org/Tool/FDC‏ 711 ‏ار تشكل قذيهي كه امكان محاسيه:و ازائه متجنن هاي طول مدت جریان را فراهم میور‎ 1 ١ ‏اين منحنى ها اغلب در ارزيابى خشکسالی هیدرولوژیکی استفاده می شوند. منحنی های طول مدت جریان را می‎ ‏توان از کل سری زمانی وارد شده پا از قسمت های تعریف شده مانند بخش های سالانه پا ماهانه ایجاد کرد‎ ‘The whole time-series ‘Ini ual years ‘Individual months ic time period (defined by build- FOC - Years [if] ‏عق عم‎ ]5[ ۴۳۵۲ - ‏فعتع5۵‎ ۵ [E= _ Caution Manager 3 FOC -Leng Ter, FOC Years, Months 

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17 معرفی نرم افزاز نرم اقزار مورد استفاده: ‎https://hydrooffice.org/Tool/FDC‏ ‎NICSE‏ رارش لك بروندء داده ورودى» ابزار به شما امكان مى دهد متحين شاى مدت را تطور خودكار براى تعداد زيادى از قايل هاى ورودى أماده , بدون دخالت كارير , محاسبه كنيد. در برنامه مى «اء_ما.ا_ا. ‎ ‎ ‎ ‎ ‎‘Individual years ۰ pe ae 3 ‎۰۱۱01۷ ۵ ‏اون‎ ۵ | ee -Whole time-serie: 

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منبع 18 USGS Searchy - Flow Duration Curves .1 * * 2. مدل منطقه اي منحنی تداوم جریان حوزه های آبخیز بدون آمار مناطق خشک(مطالعة موردی: ایران مرکزی)/ مجله منابع طبیعی ایران/1392 ۶ 3. بررسی و تعیین عوامل موْثر بر شکل منحنی تداوم جریان در اقلیم هاي مختلف ایران/نشریه پژوهش حفاظت آب و خاک/1397 Flow- Duration Curves/James K. 6۲6/1969 4 ۰ Manual on Low-flow Estimation and Prediction/WMO/2009 .5 

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Sumer & Winter Low flow تاه 2. LOW FLOW INDICES (LFI) 

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eee ST Sag ae 1 Hydrological processes and catchment storages (modified from Tallaksen and van Lanen, 2004) Soom | 20 Low flows occur after periods of low rainfall or when precipitation falls as snow. This results in a reduction in water stored in soils, aquifers and lakes and a decrease in the outflow to the river. The timing of depletion depends primarily on antecedent weather conditions. The rate of depletion depends on hydrological processes and the storage properties within the catchment. Low flows usually occur during a long spell of warm, dry weather typically associated with high pressure systems and subsiding air. High temperatures, high radiation input, low humidity and wind increase evapo- Tation and transpiration rates. Snowfall and snow storage result from temperatures continuously below freezing which are often associated with cold, polar air masses and/or decreasing temperatures at higher altitudes. In the absence of snowmelt, precipitation will accumulate and this will lead to a reduction in low flows. 

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pe 4 ‏تعريف‎ The term “ low flow indices” is used for: Base Flow Index: specific values derived from an analysis of low flows. Hydrograph separation techniques generally divide the The first two indices in this chapter describe the propor- total streamflow into a quick component and a delayed tion of base flow in a river and the recession constant. component. The delayed flow component, commonly They are followed by three fiow statistics, the nBFI=V,,/V,,, 27d to as the base flow Q,. represents the proportion mean annual minima and the 95 percentile exceedance _! flow that originates from stored sources. A high index of base flow would imply that the catchment is able to discharge (Q,,). Many decisions on the design or ma- in siver flow during extended dry periods. Base- nagement of water resources are based on these indices. guy indices are generally highly correlated with the Examples include using recession analysis for low-flow hydrological properties of soil, geology and other forecasting and using Q,, for preliminary assessment storage-related descriptors, such as lake percentage when establishing water abstraction licences. The base-flow index (BFI) is presented below, and a review of altemative automated separation procedures can be found in Nathanand McMahon (1990), The BFI is the ratio of base flow to total flow calculated. ‘om a hydrograph separation procedure 

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تعریف Low Flow Statistic: 8 5 ۶ 5 5 ۸ 5 ٩ 8 6 ۶ ۶ ۶ Mean flow 33.22 8 2 2 8 2 3 ۶ § § The mean flow is one of the most commonly used statistics in hydrology and water resources planning. It can be estimated from a time series of gauged data by summing all daily discharges and dividing by the number of days in the record. It is nonnally cal- culated for complete calendar or hydrological years of data It can also be calculated for specific months or seasons. Flow (umes) Base-flow separations for an impermeable (top) and permeable catchment (bottom) in the United Kingdom 

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Determining stream baseflows using (low) flow indices Flow Index Definition Tennant (1976) 0.30°(ADF) 30% of the average daily flow (ADF) U.S. Fish and Wildlife 0501 5 New England Aquatic Base Flow method Service (1981) (based on the August median monthly flow) Ries (1997) ‘August median flow | Considered as a uniform aquatic baseflow policy for water resources Wallace and Cox ‏0و۵‎ Used as a conservative estimator of mean (2002) baseflow Hayes and Nelms Qo Estimator of mean baseflow in some regions (2001) of Virginia Qs0/Qs0 Baseflow variability index Petts et al. (1997) 6/۵ Groundwater (baseflow) dominated streams have values ranging from 2.5 to 6.5 U.S. Environmental 30Q2 The minimum 30-day flow with a two year Protection Agency return period (2003) 772222272972278 

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24 Low Flow Statistic: ‏دعر یف‎ Ninety-five percentile flow: Q,, Mean annual minima: MAM (n-day) This is one of the most common low-flow indices used = Annual minima can be derived from a daily flow se- operationally and is defined as the flow exceeded for95 _ ties by selecting the lowest flow every year and the per cent of the time. It can be determined by ranking all eau of the minima calculated. Minima of different daily discharges and finding the discharge exceeded by “mations can be determined. with 1. 7, 10. 30 and 90 95 per cent of all values. Q,, can also be derived from individual oe eae oe months, for groups of months or any specified periods. ۱ 9 : mating the frequency or return period of low flows Other percentiles can similarly be derived from the (section 7.5). In temperate climates, the mean annual flow-duration curve. 7-day minima is numerically similar to Q,, for most flow records. 

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دح نا Discharge (Q) fa tea ‏وا‎ ea 0 tea is tes ta ter : Schematic representation of a sequence of runs with examples of total deficit, duration, mutual dependent events and minor events. Discharge (Q) is shown as a grey line and the low-flow 7 threshold (Q95) as a black line ١ 

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2 5 0 om 0 ۳2۳ % of time exceeded ‘Type cares ond frequency relationship for flow duration curve 3 Day Cane لاه 0 هه و2 هه مد ؤم 65 ‎Protng positon W‏ f 1 Ren peice (years) Low flow frequency curve estimation procedure 

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Magnitude of low flow events Wood et al. (2000) Wood et al. (2000) Clausen et al. (2000) Poff and Ward (1989) 5 km Mean minimum monthly flow for all months Mean of the lowest annual daily flow divided by median annual daily flow averaged across all years Median of the lowest annual daily flows divided by median annual daily flows averaged across all years Mean annual minimum flows divided by catchment area Mean of the lowest annual daily flow divided by mean annual daily flow averaged across all years Minimum monthly flows. Annual minimum flows Low flow index 

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Clausen and Biggs (1997, 2000), Clausen et al. (2000) Richter et al. (1998) Poff (1996) Magnitude of low flow events Ratio of baseflow volume to total flow volume Seven-day minimum flow divided by mean annual daily flows averaged across all years Mean of the ratio of the lowest annual daily flow to the mean annual daily flow (*100) averaged across all years Baseflow index (1) Baseflow index (2) Baseflow index (3) 

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‘Sources Richter et al. (1996, 1997, 1998) Clausen et al. (2000) Clausen and Biggs (1997, 2000), Clausen et al. (2000) Richter et al. (1996, 1997, 1998) Poff and Ward (1989), Poff (1996), Richter et al. (1997) Puckridge et al (1998) Duration of low flow events Explanation Magnitude of minimum annual fow of various duration (1-, 3-, 7-, 30-, 90-day), ranging from daily 10 ‘seasonal Mean annual 1-day/7-day/30-day minimum, respectively, divided by median flow Mean magnitude of flows exceeded 75% and 90% of the time, divided by Qo over alll years (Qs/Qso, Qs0/Qeo) Mean duration of low flood pulse count Mean annual number of days having zero daily flow Percentage of all months with zero flow Index Annual minima of daily discharge Means of minima of daily discharge Low exceedence flows Low flow pulse duration Number of zero-flow days Percent of zero-flow months 

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{Flow duration indices used for low flow study Riggs (1880), Brilly etal. (1857) Smakbiin (2001), Wallace and Cox (2002), ‘Thame (2003) Peiis etal (1997) Michigan Depariment of Environmental Quality (2002) Higgs and Pets (1905), ‘Smakhtin and Toulouse (1998) Dakova etal. (2000) Stewardson and Gippel (2003) ‘Smakhbn etal (1905), ‘Smakitin (2001) ‘Caissie and Er-Jabi (1995) Yoram and Burn (1998) ‘Ogunkoya (1989) Rivera: Ramirez et al. (2002) Wallace and Cox (2002) Ries and Friesz (2000), Ries (1997) USS. Fish and Wildlife Service (1961) Metcalfe et at 2008) ~ commonly used low flow index or indicator of extreme low flow conditions 30 ‘minimum flow to protect the iver * minimum monthly condition for point discharges ‘icensing of surface waler exachons and effluent discharge limits assessment = biological index for mean monthly How ‘+ used fo maintain the natural monthly seasonal variation ‘used to optimize environmental low rules + commonly used low flow index ‘monthly value provides stable and average flow conditions, “= monthly value gives minimum fow for aquatic habitat “used to examine discharge-duralion pattems af small sireams * threshold for warning waler managers of entical streamflow levels “ deseries limiting sireamiiow conditions, and is used as a conservative estimator of mean baseflow ~ aquaiic baseflow policy for water resources planning and management ‘used fo protect aquatic biota ‘used 16 recommend Seasonal minimum discharges for waterpower rivers 80 

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Other low flow indices ‘Ohio Environmental Protecton Agency Division of Surface Water (1997) Virginia Department of Environmental Quality (2004) TS. Environmental Protection Agency (1999) New Yor State Deparment oF Environmental Conservation (1996) TriState Water Gualiy Counel (2004) Minnesota Offce ofthe Revisor of Statutes (2004) Waltemeyer (2002) Michigan Department of Environmental Quality (2002), ‘Ohio EPA Division of Surface Water (1987) Minnesota Offee ofthe Revisor of Statutes (2004) TS. Environmental Protection Agency (2003) ‘stream design flow used lo determine waste load allocations to maintain water quality ertera for NHeN toxicity: May-November for summer chronic aquatic life, December February for winter chronic aquatic hfe * default design low flow for calculating sleady state waste load allocations for aquatic lie: chronic erteria (ammonia) * chronie enteria for aquatic Ife regarding ammonia or ammonia-nitrogen loadings + Total maximum daily oad o assess human heallh protection of drinking water resources + the basis for monitoring the attainment ‏لما اه‎ stream water qualty fow targets .» wasle load allocations for point Sources + chronic erterta for aquatic life + design for Total maximum daly Toads for various water quality constituents * design flow for wildlife values Such as mereury “= waste load allocation for discharges into Rowing receiving waters for wilde erteria 015 chronie standard or criterion for waste load allocations + a reasonable estimate of annual average basefiow for any given year 203 00 3002 

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Other low flow indices Carier and Putnam (1978) 115 Protection Agency (1999) Virginia Department oF Environmental Quality (2004) Ohio EPA Division of Surface Water (1287) Tinnescta Offce ofthe Revisor of Statutes (2004) US. Environmental Protection ‘Agency (1999) Virginia Depariment of Environmental Quality (2004) ‘Ohie EPA Division oF SurIaCe Water (1997) Minnesota Office ofthe Revisor of Statutes (2004) Schreier (1098) US Environmental Protection Agency (1999) Bingham (1986) ~ general indicator of nial drought conditions Which may cover large areas ‘+ may be used by State regulators to determine water use restrictions * the eriterion maximum concentration (ammonia) for aquatic life ~ default design low flow far calculating steady state waste load allocations for aquatic hie: acute ‏وی‎ 7 receiving waters for acute aquatic life erteria {except for ammonia-nitrogen) ‘maximum standard or erierion for waste [oad allocations 7 design Tow for the continuous chronic erferon for ammonia * defaull design low flow for calculating steady state waste load allocations for human health. ‏هو‎ 2/۵8 load allocation for discharges into Towing receiving waters for agricultural water Supply, human health, and aesthetic eitria “ hurnan health ehronic standard or efiterion for waste load allocations ‘fo evaluate the effects fom contaminated ‘groundwater “flow for implementing the human health erteria for carcinogens. “= parmissile rate of wasie disposal into Tennessee stieame B2 15 3005 هد ‎mean fow‏ 3020 

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> وچ وووووووعووووووووووووو BI 77۸ Hydrologically based low flow estimates using: a) flow indices, and b) flow duration &» |] 

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t=t+1 LISFLOOD daily run Qa 3 4hreshold check Os Que ‏سلتو سس ساسح‎ Pooling Ir >be Ma Ste Ger >be Gx Ste = + 3 8,2 8 2, - ‏ريو‎ - © Dia (Qos: Q) d= ds 4,21 9 ‏1+ييك‎ ‏یو ,و‎ 9,20 9۹ 1۳۹۹۹ 20700032 2-----2 Yes t= dekades (10,20,31,...) + No ۳ 1 0۶۵۵25 7۳۳ 025 > ۶۵20۵ Minimum size d,> d, | ——+ (Da) = 1- e+ ‏زقو ان‎ Hl ©. 3A) $0. 55 ۲:۸ 5 Drought Classification Flowchart describing the computational scheme for the implementation of the Low-Flow Index (LFI) within the Copernicus European Drought Observatory (EDO). 

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‎dekade 3" dekade‏ 24 تست ‎ ‎35 i ‎June ‎August ‎Figure 6. Sequence of Fy dekadal maps for summer (May-August) 2015 in Central Europe. The land cells with drainage area ‎<1000 km? are depicted in grey; the main rivers are coloured according to the scheme: no-drought: white, mild: yellow, moderate: orange, severe: red, extreme: maroon (see Fig, 2). ‎ 

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كاربرد Low-fiow statistics provide a valuable estimate of the conditions experienced during the dry season. For rapid assessment of the availability of water for abstraction in temperate regimes, simple flow statistics such as ‏بر‎ ‎are often used to assess the amount of water available at low flows. For public water supply. a constant ab- straction is often required, perhaps with seasonal va- siability. A second commen application of both Q,..and the mean of the 7- or 10-day annual minima is that of irrigation scheme design. This involves estimating the potential area that can be irrigated by the supply river for schemes without storage. If there is a seasonal variability in irrigation demand, then flow statisties can be determined for specific months or groups of months. For preliminary design, Q,, is also used to assess the availability of water for the dilution of industial or domestic effiuents. Water quality models based on the rate and quality of the effiuent and the flow and quality, of the receiving stream are used to determine the fre- quency distribution of downstream water quali ‘The BBIQas been used primaily asa general index of catchment response. Ithas had its widest application in regional low-flow studies in the United Kingdom (Gustard and others, 1992), where it is now routinely calculated for over 1000 gauged records published in the United Kingdom National Water Archive (CEH, 2003). The BET has also been used to classify the hydro logical response of soil types for regional fiood studies (Boorman and others, 1995). Furthermore. it has been implemented as a general catchment descriptor for hydrological modelling (Chapter 9). as a tool for se- lecting analogue catchments, and for estimating annual and long-term groundwater recharge. The BFT has been used not only in the United Kingdom, but also in Jow- flow studies in mainland Europe, New Zealand, Souther Africa and the Himalayas, It has also had extensive use in Canada (Piggott and others. 2005). where it has been mapped in support of regional low-flow studies and ‘used to map recharge and discharge zones, to investigate the impact of climate change on groundwater resources and also to relate flood response to soil type. 

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57 List of parameters to predict Ontario low flows (from Belore, ‏پیش ا‎ Physiographic Description Physiographic © Drainage area (DA, km”) * Base flow index (BF, dimensionless) * Maximum groundwater fluctuation (m) * Slope (m km") © Stream length (LNTH, mm) * Degree of regulation (0 for natural, 1 for regulated) « Drainage area controlled by lakes and swamps Hydrometeorological | * Mean annual precipitation (mm) Mean annual snowfall (MAS, mm) Mean annual runoff (MAR, mm) ¢ Mean annual evaporation (mm) Other parameters * Watershed location * Soil index * Quality of data (station density, record length, 2 1 FF measurement accuracy ۳ BS 

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Invorse Distance 38 ۳ ea m4) Wane ce ened Ordinary kriging IQ) ‏ی‎ ets vader of spat terplatoe echnigu: sD represetaonel ocurred 11: sesiaoa cs Rien Asin ot Pj 

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39 Wk Op ‏معرفی نرم افزار‎ LFSTAT - Low-Flow Analysis in R HELP 4 

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40 Manual on Low-flow Estimation and Prediction/WMO/2009 Hydrological Low Flow Indices and their Uses/ WSC/2004 Low-Flow Index (LFI)/ European Commission/2018. Prediction of low-flow indices in ungauged basins through physiographical / ELSEVIER/2009 Low Flow Estimation in the United Kingdom/Institue of Hydrology/ Development of an operational low flow index for hydrological drought monitoring over Europe/Hydrological Sciences Journal/2017