doktorska disertacija
Povzetek
Razumevanje in poznavanje procesov, ki sestavljajo vodni oziroma hidrološki ter erozijskosedimentacijski
krog, ki se medsebojno prepletata, je pomembno z vidika varstva pred naravnimi nesrečami ter zagotavljanja ustreznih pogojev za življenje (npr. pitna voda). V doktorski disertaciji
so obravnavani naslednji procesi:
uvialno premeščanje suspendiranih snovi, površinski
odtok vode, padavine ter erozijski procesi.
V disertaciji so najprej opisani in predstavljeni hidrološki procesi, sledi opis merskih metod, ki
so bile uporabljene za izvedbo meritev. Nadalje je podan opis obravnavanih porečij vključno
z eksperimentalnim porečjem, kjer so se meritve z visoko frekvenco vzorčenja izvajale v okviru
doktorske disertacije, sledi opis uporabljenih statistično-matematičnih metod, ki so bile uporabljene
za analizo podatkov, pri tem je poudarek na funkcijah kopula, ki omogočajo hkratno
analizo dveh ali več v naravi bolj ali manj odvisnih spremenljivk. V zadnjem poglavju prvega
dela disertacije pa so prikazane osnove modeliranja erozije tal s poudarkom na modelu WATEM/
SEDEM.
V drugem delu disertacije so prikazani rezultati različnih terenskih meritev (npr. meritve
uvialnega
premeščanja suspendiranih snovi, padavin, pretokov, erozije tal), izvedena je analiza
povezanosti
uvialnega premeščanja suspendiranih snovi z drugimi hidrološkimi procesi, prikazani
so rezultati modeliranja erozije tal ter uporabe funkcij kopula.
Ugotovili smo, da imajo padavinski dogodki velikih intenzitet nadpovprečen vpliv na procese
sproščanja, premeščanja in odlaganja erozijskega materiala. Količine premeščenega materiala so
lahko pri teh dogodkih nekaj velikostnih razredov večje od dolgoletnega povprečja. V Sloveniji
do nastopa konice
uvialno premeščenih suspendiranih snovi večinoma prihaja pred nastopom
konice pretoka, pri tem pa so časovne razlike večinoma relativno majhne (do 1 dneva). Nadalje
se količine
uvialno premeščenih suspendiranih snovi v slovenskih vodotokih večinoma zmanjšujejo, kar je lahko posledica različnih vzrokov, kot sta zaraščanje površja zaradi opuščanja
kmetijske obdelave ter zapiranje rudnikov. Z aplikacijo modela WATEM/SEDEM na 5 porečjih
v Sloveniji je bilo ugotovljeno, da se koeficient odplavljanja zmanjšuje z večanjem prispevnega
območja. Funkcije kopula pa so bile uporabljene za multivariatne verjetnostne analize poplavnih
dogodkov, kjer smo hkrati upoštevali konice pretokov, volumne visokovodnih valov ter trajanja
visokovodnih valov, poleg tega pa smo funkcije kopula uporabili tudi za analizo podatkov o
suspendiranih snoveh ter za ocenjevanje vrednosti
uvialno premeščenih suspendiranih snovi na
podlagi podatkov o pretokih in padavinah.
Ključne besede
Grajeno okolje;gradbeništvo;disertacije;sedimenti;erozija tal;modeliranje;funkcije kopula;eksperimentalno porečje;
Podatki
Jezik: |
Slovenski jezik |
Leto izida: |
2016 |
Tipologija: |
2.08 - Doktorska disertacija |
Organizacija: |
UL FGG - Fakulteta za gradbeništvo in geodezijo |
Založnik: |
[N. Bezak] |
UDK: |
556.512:551.311.21:(497.12):(043) |
COBISS: |
7476065
|
Št. ogledov: |
2254 |
Št. prenosov: |
601 |
Ocena: |
0 (0 glasov) |
Metapodatki: |
|
Ostali podatki
Sekundarni jezik: |
Angleški jezik |
Sekundarni naslov: |
Fluvial transport of suspended sediments related to other hydrologic processes |
Sekundarni povzetek: |
Understanding and knowledge about the processes that define water or hydrologic cycle and
erosion-sedimentation cycle (these two cycles are inter-connected) is important in order to ensure
safety during natural disasters and to provide suffcient conditions for life (e.g. drinkable
water). In the presented thesis we investigated next processes:
uvial transport of suspended
sediments, surface runoff, rainfall and erosion processes.
Firstly, the investigated hydrological processes are described, then the measuring methods
are presented. Further, the investigated catchments including experimental catchment where
high-frequency measurements were performed are described, in the next section the statisticalmathematical
tools that were used for data analysis are shown. The emphasis was given to
the copula functions that can be used for simultaneous study of two or more (in)dependent
variables that define the environmental process. In the last section of the first part of thesis,
the basic concepts of soil erosion modelling are presented where the emphasis was given to the
WATEM/SEDEM model that can be used for soil erosion modelling.
In the second part of the thesis, results of field measurements are presented (e.g. measurements
of
uvial transport of suspended sediments, rainfall, discharge and soil erosion), analysis of connection
between
uvial transport of suspended sediments and other hydrological processes was
carried out, soil erosion modelling results are described and application of copula functions is
shown on practical examples.
The main conclusions are: rainfall events that have large rainfall intensities have significant impact
on erosion, transport and deposition processes. During these kinds of events the suspended
sediment budgets can be for a few orders of magnitude larger than the long-term annual rates. In
Slovenia the peak of the suspended sediment transport mostly occurs before the peak discharge
but the time differences are rather small (up to 1 day). Moreover, the trends in the transport of
suspended sediments in Slovenian streams are mostly negative (all statistically significant trends
are negative). Reasons for this can be: closing of mines or foresterisation (abandoning of farming
due to urbanisation). Application of the WATEM/SEDEM model showed that sediment delivery
ratio decreases with increasing catchment area. Moreover, copula functions were used for
multivariate
ood frequency analysis where peak discharge, hydrograph volume and hydrograph
duration were considered in the analysis. Moreover, copula functions were also used to analyse
suspended sediment data and for the estimation of the suspended sediment values based on the
measured discharge and rainfall values. |
Sekundarne ključne besede: |
Built Environment;civil engineering;doctoral thesis;sediments;soil erosion;modelling;copula functions;experimental catchment; |
URN: |
URN:NBN:SI |
Vrsta datoteke: |
application/pdf |
Vrsta dela (COBISS): |
Doktorsko delo/naloga |
Komentar na gradivo: |
Univ. v Ljubljani, Fak. za gradbeništvo in geodezijo |
Strani: |
XIV, 58 str., 9 pril. |
ID: |
9144306 |