Izračun indeksov baznega odtoka (BFI) za vodomerne postaje državnega hidrološkega monitoringa : diplomska naloga

Srebovt, Anže (author), Šraj, Mojca (mentor), Kobold, Mira (co-mentor)

Bazni odtok je poleg površinskega odtoka ena od dveh glavnih komponent, ki sestavljajo celoten odtok vodotoka. Bazni odtok predstavlja odtok iz naravnih podzemnih skladišč in zapoznelih virov (npr. taljenja ledu in snega). Prisoten je tudi v času sušnih obdobij in tako zagotavlja tok vode v rečni strugi. Na podlagi merjenih podatkov o pretoku lahko izračunamo indeks baznega odtoka (BFI). Ta je definiran kot brezdimenzijsko razmerje med volumnom baznega odtoka in celotnim volumnom odtoka. BFI je dober pokazatelj vplivov geologije na nizke pretoke in zaradi tega se ga pogosto uporablja v številnih regionalnih raziskavah nizkih pretokov. V prvem delu diplomske naloge so teoretično predstavljene komponente hidrograma in baznega odtoka. Prikazane so metode izločanja baznega odtoka: grafične metode, avtomatizirani postopki, fizikalni pristopi, kemijski pristopi. Poleg tega je podrobneje opisan program, s katerim se izloča bazni odtok in izračuna indeks baznega odtoka, BFI for Windows. V drugem delu diplomske naloge so predstavljeni rezultati analize 196 vodomernih postaj državnega hidrološkega monitoringa, pridobljeni s pomočjo programa BFI for Windows. Izračunane povprečne vrednosti BFI posameznih vodomernih postaj so razdeljene v razrede z intervalom 0,2 in prikazane na karti. Rezultati analiz kažejo, da je BFI v precejšnji meri odvisen od geološke podlage, hkrati pa tudi od drugih dejavnikov, kot je npr. naklon prispevne površine.

• Language: Slovenian
• Keywords: gradbeništvo, diplomska naloga, UNI, B-VOI, indeks baznega odtoka, BFI, bazni odtok, BFI for Windows, hidrogram
• Work type: Bachelor thesis/paper
• Typology: 2.11 - Undergraduate Thesis
• Organization: FGG - Faculty of Civil and Geodetic Engineering
• Place of publishing: Ljubljana
• Publisher: [A. Srebovt]
• Year: 2014
• Number of pages: X, 44 str., 1 pril.
• PID: 20.500.12556/RUL-32456
• UDC: 556.167(043.2)
• COBISS.SI-ID: 6802273
• Publication date in RUL: 10.07.2015

Secondary language

• Language: English
• Title: Calculation of the base flow index (BFI) for the gauging stations of the national hydrological monitoring

Abstract

Base flow, in addition to quick flow, is one of two main components that make up the entire drain of the stream. Base flow represents water from the underground storage and delayed sources (e.g. melting ice and snow). It is present even during drought periods, thus ensuring the flow of water in the stream. Based on the measured discharge, the base flow index (BFI) can be calculated. This is defined as the dimensionless ratio of the volume of the base flow and the total volume of water in the stream. BFI is a good indicator of the effects of geology on low flow rates and for this reason it is often used in a number of regional studies of low flows. First part of the thesis presents components of hydrograph and base flow on theoretical grounds. It shows the methods of elimination of base flow: graphical methods, automated procedures, physical approaches, chemical approaches. In addition is a detailed description of the program, BFI for Windows, by which is excreted base flow and calculated base flow index. The second part of the thesis presents the results of the analysis of 196 gauging stations of the national hydrological monitoring, obtained by using software BFI for Windows. Calculated mean BFI values of the individual gauging stations are divided into classes with an interval of 0.2 and shown on the map. The results led to the conclusion that BFI is depended on the geology in a great manner, but at the same time also on other factors, e.g. catchment slope.

• Keywords: base flow index, BFI, baseflow, BFI for Windows, hydrograph