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V magistrski nalogi je obravnavana tematika odvodnje padavinske vode z tramvajskih prog v urbanih območjih. Predstavljene so različne rešitve za odvodnjo padavinske vode na tramvajskih progah v dveh mestih, Portu in Sarajevu, pri čemer so opisani tudi sestavni deli drenažnih sistemov na tramvajskih progah ter njihova funkcija. Rešitve so prilagojene različnim parametrom, kot so lastnosti terena in intenziteta padavin, pri čemer smo se osredotočili na razlike v hidroloških značilnostih območij, povratnih dobah ter različnih metodah odvodnjavanja. V nalogi smo predstavili različne površine z značilnostmi terena ter s pomočjo različnih koeficientov odtoka, časov koncentracije, trajanja padavin itd. prikazali in komentirali razlike. Poleg tega smo v nalogi predstavili tudi različne rešitve za odvodnjo padavinske vode z območja tramvajske proge, med drugim tudi infiltracijske sisteme, ki omogočajo naravno filtriranje in ponovno uporabo vode ter so prijazni do okolja. V nalogi smo se osredotočili na izboljšanje odvodnjavanja padavinske vode na tramvajski progi v Sarajevu. Predstavili smo dva pristopa - prvi, konvencionalni pristop, bi zahteval postavitev različnih delov sistema, kot so jaški, odvodni kanali in cevi. Drugi, alternativni pristop, bi vključeval uporabo infiltracijskih sistemov, kot so jarki s perforiranimi odvodnimi cevmi in modularni bloki, ki bi pomagali pri zbiranju in odvajanju vode. Ta rešitev bi razbremenila mestni sistem odvodnjavanja in zmanjšala količino vode v mestnih vodotokih, kar bi bilo koristno za okolje. Pri primerjavi obeh rešitev smo upoštevali tehnično izvedljivost in stroškovno učinkovitost ter podali celovito oceno. Za obnovo tramvajske proge smo pripravili tudi podroben finančni načrt in popise del, ki bi bili potrebni za izvedbo projekta. Po naši analizi smo ugotovili, da je uporaba infiltracijskih sistemov boljša rešitev za odvodnjavanje tramvajske proge v Sarajevu. Ta rešitev omogoča boljšo izrabo naravnih virov ter hkrati zmanjšuje obremenitev mestnega sistema odvodnjavanja. Poleg tega je stroškovno učinkovitejša in lahko zmanjša stroške vzdrževanja sistema na dolgi rok. S tem bomo zagotovili dolgoročno učinkovitost sistema ter trajnostno upravljanje s padavinsko vodo na tramvajski progi v Sarajevu. The subject of the master's thesis is rainwater drainage from tram lines in urban areas. The thesis presents various solutions for draining rainwater from tram lines in two cities, Porto and Sarajevo. The thesis describes the components of drainage systems on tram lines and their functions. The solutions are adapted to various parameters, such as terrain characteristics, rainfall intensity, and return periods, and focus on different drainage methods. For the assignment, we presented different surfaces with varying terrain characteristics and used different runoff coefficients, concentration times, and rainfall durations to demonstrate and comment on the differences. In addition, we presented various solutions for draining rainwater from the tram line area, including infiltration systems that allow for natural filtering and water reuse, which are environmentally friendly. Our focus for the assignment was on improving rainwater drainage on the tram line in Sarajevo. We presented two approaches: the conventional approach involving the installation of shafts, drains, and pipes, and the alternative approach using infiltration systems such as trenches and modular blocks to collect and drain water. This solution would reduce the amount of water in the city's waterways and alleviate the burden on the city's drainage system, which would benefit the environment. After comparing the two solutions, we assessed their technical feasibility and cost-effectiveness comprehensively. We prepared a detailed financial plan and a list of necessary works for the tram line reconstruction. Based on our analysis, we concluded that the use of infiltration systems is a better solution for draining the tram line in Sarajevo because it allows for better use of natural resources, reduces the burden on the city's drainage system, is more cost-effective, and can reduce maintenance costs in the long run.

Pressures to combat the coronavirus disease 2019 (COVID-19) pandemic have led to accelerated efforts to develop vaccines and therapeutics. The spike (S) protein, which is a key target of these efforts is metastable and challenging to recombinantly generate. Using a structure-guided approach, we characterized 100 spike designs, 26 of which improved protein yields. Combinations of the beneficial substitutions led to the development of HexaPro, a S protein variant with a 10-fold higher expression than the parental construct enhanced thermal-stability, due to six proline substitutions. Further structural and antigenic characterization of HexaPro confirmed a prefusion stabilized S protein with conserved ACE2 and antibody binding. The improved yield and stability of HexaPro has accelerated the development of serological diagnostics and vaccines for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Spike is also undergoing immunogenic selection with variants that increase infectivity and partially escape convalescent plasma. I developed Spike Display, a high-throughput platform to rapidly characterize glycosylated S ectodomains across multiple coronavirus-family proteins. I assayed ∼200 variant SARS-CoV-2 spikes for their expression, ACE2 binding, and recognition by 13 nAbs. An alanine scan of all five N-terminal domain (NTD) loops highlights a public epitope in the N1, N3, and N5 loops recognized by most NTD-binding nAbs. NTD mutations in the alpha, beta, gamma, epsilon, and delta impact spike expression and escape most NTD-targeting nAbs. Finally, beta and gamma completely escaped a potent ACE2 mimic. The continuous spread and evolution of SARS-CoV-2 has led to the repeated emergence of variants of concern. For the Omicron variant, sub-lineages BA.1 and BA.2 respectively contain 33 and 29 nonsynonymous and indel spike protein mutations. These amino acid substitutions and indels are implicated in increased transmissibility and enhanced immune evasion. By reverting individual Spike mutations of BA.1 or BA.2, I characterized the molecular effects of the Omicron spike mutations on expression, ACE2 receptor affinity, and neutralizing antibody recognition. I identified key mutations enabling escape from neutralizing antibodies at a variety of epitopes. Stabilizing mutations in the N-terminal and S2 domains of the spike protein can compensate for destabilizing mutations in the receptor binding domain, enabling the record number of mutations in Omicron. My results provide a comprehensive account of the mutational effects in the Omicron spike protein and illuminate previously uncharacterized mechanisms of host evasion. I anticipate that Spike Display will accelerate antigen design, deep scanning mutagenesis, and antibody epitope mapping for SARS-CoV-2 and other emerging viral threats.

Extremely intensive hourly precipitation is one of the major cause of floods. Hence, it is necessary to investigate hourly precipitation extremes to be proactive at flood risk management. This paper applys Metastatistical Extreme Value (MEV) for estimation of current and future 1 in 10 to 100 year return values of hourly precipitation from short records with the duration around 10 years. Extreme Value Theory (EVT), including Generalized Extreme Value (GEV) and Peak-Over-Threshold (POT), has been prevalent in hydrology frequency analysis since last century. However, the asymptotic assumption of EVT and very often not-large-enough data records in practical cases limit the application and development of EVT. MEV is a novel method in extreme value analysis by considering ordinary events as well as the extremes. Compared with traditional EVT, MEV is a non-asymptotic approach and it estimates high quantiles by considering all or most of independent ordinary events in the process of estimation return values. In this paper, MEV is applied to three different datasets to investigate the mechanism of MEV from various aspects and to assess the performance under different thresholds. The first is KNMI dataset. With up to 95 years of historical hourly rainfall observations in the Netherlands, it is used to analyze the influence of sample data and thresholds on the MEV estimates, as well as for error analysis. Subsequently, a DWD dataset, with 1035 station observations covering Germany, is used for the analysis of the spatial distribution of the hourly rainfall extremes. Finally, an EUCP dataset of kilometre-scale gridded data covering Europe generated by the UKMO Connective Permitting Regional Climate Model (CPRCM) is used. It includes an evaluation run forced by ERA interim reanalysis, a historical run and two future runs downscaled from CMIP5 GCM. The evaluation run is also used for spatial analysis to support the applicability of MEV to climate model simulation data. The historical run and two future runs were used to investigate the mid-century and end-of-century variability of 10-year, 50-year and 100-year hourly precipitation. MEV, with 75 percentile as threshold, is more advantageous than traditional extreme value analysis methods in the case of small sample data. This is reflected in the fact that MEV has smaller errors, less uncertainty and better spatial expressiveness. Applying MEV to the EUCP dataset provides a glimpse of the variation of hourly rainfall extremes in the future: by mid-century, the increase of hourly rainfall extremes is not significant, while the second half of the century faces a significant increase. This increase is also related to the topography, with more pronounced in the Alpine and Mediterranean coastal regions. Izjemno intenzivne urne padavine so eden glavnih vzrokov za poplave. Zato je treba raziskati urne ekstremne količine padavin, da bi bili proaktivni pri obvladovanju poplavne ogroženosti. Ta članek uporablja metastatistično ekstremno vrednost (MEV) za ocenjevanje sedanjih in prihodnjih urnih padavin s povratno vrednostjo 1 na 10 do 100 let iz kratkih zapisov, ki trajajo približno 10 let. Teorija ekstremnih vrednosti (EVT), vključno s posplošeno ekstremno vrednostjo (GEV) in teorijo vršnega praga (POT), je v hidrološki frekvenčni analizi razširjena že od prejšnjega stoletja. Vendar asimptotska predpostavka EVT in zelo pogosto premajhna količina podatkov v praktičnih primerih omejujeta uporabo in razvoj EVT. MEV je nova metoda v analizi ekstremnih vrednosti, saj upošteva tako običajne dogodke kot tudi ekstreme. V primerjavi s tradicionalno EVT je MEV neasimptotski pristop in ocenjuje visoke kvantile z upoštevanjem vseh ali večine neodvisnih običajnih dogodkov v procesu ocenjevanja vrednosti donosa. V tem članku je MEV uporabljen za tri različne nabore podatkov, da bi raziskali mehanizem MEV z različnih vidikov in ocenili učinkovitost pri različnih pragovih. Prvi je nabor podatkov KNMI. Ta vsebuje 95 let zgodovinskih urnih opazovanj padavin na Nizozemskem in se uporablja za analizo vpliva vzorčnih podatkov in pragov na ocene MEV ter za analizo napak. Nato se za analizo prostorske porazdelitve ekstremnih urnih padavin uporabi podatkovni niz DWD z 1035 opazovanji postaj, ki pokriva Nemčijo. Nazadnje je uporabljen nabor podatkov EUCP z mrežnimi podatki v kilometrskem merilu, ki pokrivajo Evropo in jih je ustvaril regionalni podnebni model UKMO Connective Permitting Regional Climate Model (CPRCM). Vključuje ocenjevalno izvedbo, ki jo je izsilila vmesna reanaliza ERA, zgodovinsko izvedbo in dve prihodnji izvedbi, znižani na podlagi modela CMIP5 GCM. Ocenjevalni potek se uporablja tudi za prostorsko analizo, ki podpira uporabnost MEV za simulacijske podatke podnebnih modelov. Zgodovinski potek in dva prihodnja poteka so bili uporabljeni za preučevanje spremenljivosti 10-letnih, 50-letnih in 100-letnih urnih padavin sredi stoletja in ob koncu stoletja. MEV s 75 percentilom kot pragom je v primeru majhnih vzorčnih podatkov bolj ugodna od tradicionalnih metod analize ekstremnih vrednosti. To se kaže v dejstvu, da ima MEV manjše napake, manjšo negotovost in boljšo prostorsko izraznost. Uporaba MEV za podatkovno zbirko EUCP omogoča vpogled v spreminjanje urnih ekstremnih vrednosti padavin v prihodnosti: do sredine stoletja povečanje urnih ekstremnih vrednosti padavin ni znatno, medtem ko se v drugi polovici stoletja znatno poveča. To povečanje je povezano tudi s topografijo in je izrazitejše v alpskih in sredozemskih obalnih regijah.

The Dutch province Limburg is characterized by sloping terrain and is therefore prone to serious damages during flash floods. This was also the case for the July 2021 flood event. The study focuses on a detailed hydrological analysis and the generation of deterministic flood forecasts of the tributaries of the Meuse River in Limburg (i.e. Rur, Niers and Swalm rivers). For hydrological modeling, the wflow_sbm model was used which is a distributed hydrological model and its parameters were estimated with the Iterative Hydrography Upscaling (IHU) method and from Pedo Transfer Functions (PTFs). The horizontal hydraulic conductivity fraction (KsatHorFrac) parameter for the Rur catchment was calibrated to generate deterministic forecasts. Due to the significant difference between the observed and the simulated discharges of the Niers and Swalm catchments it was not possible to calibrate their hydrological models. Probable reasons for this difference can be the effects of ground water abstractions for pit mining and other purposes, frequent mowing management in the Niers catchment etc. Therefore forecasts were generated only for the Rur catchment by coupling the wflow model with Delft-FEWS. The forecasts generated using the DWD ICON dataset showed substantial error when compared to the observed discharge. However, for the flood event of 2021, the model predicted high flows 5-6 days ahead of the flood. There was a large overestimation of the peak for the forecast in downstream of the Rur catchment. The sensitivity of the forecast performance by changing KsatHorFrac was also analysed in the end. The findings of the study show several scopes of improvements in the wflow hydrological modeling and flood forecasting of the Meuse tributaries. Future studies based on these recommendations could aid in providing a more accurate flood prediction in this region. Območje Limburga na Nizozemskem z relativno strmo topografijo terena je med poplavami julija 2021 utrpelo veliko poplavno škodo. Magistrska naloga se osredotoča na podrobne hidrološke analize in izdelavo deterministične napovedi poplav pritokov reke Meuse na območju Limburga (prispevna območja rek Rur, Niers in Swalm). Za potrebe hidrološkega modeliranja je bil uporabljen prostorsko distribuiran hidrološki model wflow_sbm, parametri modela so bili ocenjeni z metodo Iterative Hydrography Upscaling (IHU) in s pomočjo Pedo Transfer Function (PTF). Parameter horizontalne hidravlične prevodnosti (KsatHorFrac) v hidrološkem modelu prispevnega območja reke Rur je bil umerjen in na podlagi tega so bile izdelane deterministične hidrološke napovedi. Zaradi znatnih razlik med opazovanimi in simuliranimi pretoki rek Niers in Swalm ni bilo mogoče detajlno umeriti hidroloških modelov za prispevni območji teh dveh rek. Najverjetnejši vzroki za ugotovljena razhajanja med merjenimi in modeliranimi pretoki so velike količine odvzete vode za različne rabe ter izvaje regulacijskih in vzdrževalnih del v strugi reke Niers. Zato so bile hidrološke napovedi izdelane za prispevno območje reke Rur z združeno uporabo modelov wflow in Delft-FEWS. Hidrološke napoved, ustvarjena z uporabo nabora vhodnih hidrometeoroloških podatkov iz baze DWD ICON, so se izkazale kot precej nenatančne. Navkljub slabšim rezultatom simulacij je bil model sposoben za poplavni dogodek, ki se je zgodil leta 2021, napovedal visokovodne razmere 6 dni pred dejanskim pojavom poplavnega dogodka. Simulirane vrednosti pretoka so bile precenjene predvsem v spodnjem delu prispevnega območja reke Rur. Na koncu smo analizirali tudi občutljivost hidroloških napovedi na spremenjene vrednosti parametra KsatHorFraca. Izsledki študije nakazujejo možnosti izboljšav pri hidrološkem modeliranju z uporabo programa wflow in napovedovanju poplav hudourniških pritokov reke Meuse. Nadaljnje študije, ki temeljijo na naših ugotovitvah, bi lahko zagotovile natančnejšo napoved poplav v obravnavani regiji.

Extreme hydrological events have become more frequent, as evidenced by the European floods of July 2021, which affected the southern provinces of the Netherlands. The need for improved discharge predictions to be used in operational water management to avoid potential adverse effects of flooding has encouraged researchers to employ several ways to improve hydrological model estimates, including data assimilation. This thesis explores the data assimilation effects in the discharge predictions of the wflow_sbm distributed hydrological model of the Vecht river basin. Additionally, effects on other hydrological states and fluxes like subsurface flow, saturated water depth, and soil moisture were explored spatially. This work presents a methodology for applying data assimilation in a model where water is routed from the surface and subsurface. In contrast, previous studies used a model in which water is routed only via surface water. Ensemble Kalman Filter is used to update the model’s discharge predictions by assimilating external discharge observations. This methodology also explores how the data assimilation effect is influenced by the uncertainty characterization considered in the assimilation framework and other factors like the length of the assimilation window and the number of assimilation locations. A preliminary study of the rainfall data is performed to determine the uncertainties of the chosen rainfall product. A benchmark simulation scenario is then selected after the review of deterministic and ensemble model predictions. Finally, data assimilation experiments are developed after discussing the characterization of the uncertainty model. The results of the model output analysis indicate that streamflow assimilation typically has a positive effect on improving model discharge estimations. Additionally, the Ensemble Kalman Filter update effectively captures the system’s spatial state dynamics for subsurface states and fluxes, such as saturated water depth, soil moisture, etc. Two alternative experimental setups with different assimilation intervals and numbers of assimilated observations are examined concerning how this effect varies over other flow gauge locations. As demonstrated by both experiments, longer assimilation times give better results, with the assimilation effect significantly improving in the final timesteps of the assimilation frame. Furthermore, it is concluded that assimilation of observations near the outlet and interior gauges will improve discharge predictions, whereas assimilation of observations only near the outlet will only improve discharge predictions at a number of stations, typically those that are closer to the assimilation location and those where the wflow sbm model exhibits the same trend as the assimilation station. An uncertainty factor of 2.5 for the precipitation error and 0.1 for the observation error yielded the best results for both experiments. However, this study has several limitations, including assumptions of a perfect model and initial conditions the way the precipitation and observations error model was derived. As a result, the model gives unrealistic discharge predictions when compensating for the neglected errors. Additionally, a limited number of experiments due to the extensive computational times, attributed to the combination of the OpenDA tool with the distributed model, and the algorithm choice, does not allow the DA impact on the discharge predictions to be judged accurately. Therefore, the final section of this study provides recommendations for future research, suggesting additional experiments with longer assimilation windows analysis of the spatial correlation structure of precipitation, the use of more statistically reliable techniques to assess the precipitation uncertainties consideration of the model parameter and initial conditions uncertainty etc. Ekstremni hidrološki dogodki so postali vse pogostejši, kar dokazujejo evropske poplave julija 2021, ki so prizadele južne nizozemske province. Potreba po izboljšanih napovedih izpustov, ki se uporabljajo pri operativnem upravljanju voda, da bi se izognili morebitnim škodljivim učinkom poplav, je spodbudila raziskovalce k uporabi več načinov za izboljšanje ocen hidroloških modelov, vključno z asimilacijo podatkov. Diplomsko delo raziskuje učinke asimilacije podatkov pri napovedih pretoka porazdeljenega hidrološkega modela wflow_sbm porečja reke Vecht. Poleg tega so bili prostorsko raziskani učinki na druga hidrološka stanja in tokove, kot so podzemni tok, globina nasičene vode in vlažnost tal. To delo predstavlja metodologijo za uporabo asimilacije podatkov v modelu, kjer je voda usmerjena s površine in pod površino. V nasprotju s tem so prejšnje študije uporabile model, v katerem je voda speljana le po površinski vodi. Ensemble Kalmanov filter se uporablja za posodobitev napovedi izpustov modela z asimilacijo zunanjih opazovanj izpustov. Ta metodologija raziskuje tudi, kako na učinek asimilacije podatkov vpliva karakterizacija negotovosti, upoštevana v asimilacijskem okviru, in drugi dejavniki, kot sta dolžina asimilacijskega okna in število asimilacijskih lokacij. Izvede se predhodna študija podatkov o padavinah, da se določijo negotovosti izbranega produkta padavin. Po pregledu napovedi determinističnih in ansambelskih modelov se nato izbere primerjalni simulacijski scenarij. Po razpravi o karakterizaciji modela negotovosti so razviti poskusi asimilacije podatkov. Rezultati analize rezultatov modela kažejo, da ima asimilacija toka običajno pozitiven učinek na izboljšanje ocen pretoka modela. Poleg tega posodobitev filtra Ensemble Kalman učinkovito zajame dinamiko prostorskega stanja sistema za stanja in tokove pod površino, kot so globina nasičene vode, vlažnost tal itd. Dve alternativni eksperimentalni nastavitvi z različnimi intervali asimilacije in številom asimiliranih opazovanj sta preučeni glede tega, kako ta učinek razlikuje glede na druge lokacije merilnika pretoka. Kot sta dokazala oba poskusa, dajejo daljši časi asimilacije boljše rezultate, pri čemer se učinek asimilacije znatno izboljša v končnih časovnih korakih okvira asimilacije. Poleg tega je ugotovljeno, da bo asimilacija opazovanj v bližini izpusta in notranjih merilnikov izboljšala napovedi pretoka, medtem ko bo asimilacija opazovanj samo v bližini iztoka izboljšala le napovedi pretoka na številnih postajah, običajno tistih, ki so bližje lokaciji asimilacije, in tistih kjer model wflow sbm kaže enak trend kot asimilacijska postaja. Faktor negotovosti 2,5 za napako padavin in 0,1 za napako opazovanja je dal najboljše rezultate za oba poskusa. Vendar ima ta študija več omejitev, vključno s predpostavkami o popolnem modelu in začetnih pogojih način, kako je bil izpeljan model napak padavin in opazovanj. Posledično daje model nerealne napovedi praznjenja pri kompenzaciji zanemarjenih napak. Poleg tega omejeno število poskusov zaradi obsežnih računskih časov, pripisanih kombinaciji orodja OpenDA s porazdeljenim modelom, in izbire algoritma ne omogoča natančne ocene vpliva DA na napovedi praznjenja. Zato zadnji del te študije podaja priporočila za prihodnje raziskave in predlaga dodatne poskuse z daljšimi asimilacijskimi okni analiza prostorske korelacijske strukture padavin, uporaba statistično zanesljivejših tehnik za ocenjevanje padavinske negotovosti upoštevanje negotovosti parametrov modela in začetnih pogojev itd.

Water consumption is greatly rising as a result of global population growth, climate change, and other socioeconomic factors. The race to extract more water to meet the demands of various sectors is rising, making it difficult to ensure equitable water allocation. An effort was made in this study to assess the water supply and demand gap among several sectors, namely energy, agriculture, and navigation in the lower Danube river, where water is shared by Serbia, Romania, and Bulgaria. A literature review was undertaken to understand the possible approaches that may be used in this specific case. Data were collected from various sources and evaluated, to create input data for the water allocation and hydraulic models. To understand the water supply and demand imbalance under different conditions, three alternative scenarios were generated: dry, normal, and wet year periods. The Water Evaluation and Planning Model (WEAP) software tool was used to estimate the demand and supply gap in the research area for both energy production and irrigation. A hydraulic model was created utilizing the Hydrologic Engineering Center's River Analysis System (HEC-RAS) application to determine the water depth corresponding to the flow remaining in the river after energy and irrigation water consumption. In terms of water demand for energy production, the findings indicate that April has the highest demand fulfilment, while September has the lowest demand coverage. No water deficit has been found for agriculture water use, given the fact that available water in the system is much higher than the required crop water requirement (cwr) throughout the year. The hydraulic model results show that water depth is rather low in dry years, which will have a negative impact on navigation. Poraba vode močno narašča zaradi rasti svetovnega prebivalstva, podnebnih sprememb in drugih socialno-ekonomskih dejavnikov. Tekma za pridobivanje več vode za izpolnitev potreb različnih sektorjev narašča, zaradi česar je težko zagotoviti pravično razdeljevanje vode. V tej študiji smo poskušali oceniti vrzel v ponudbi in povpraševanju po vodi med več sektorji, in sicer energetiko, kmetijstvom in plovbo v spodnji reki Donavi, kjer si vodo delijo Srbija, Romunija in Bolgarija. Opravljen je bil temeljit pregled literature, da bi razumeli možne pristope, ki se lahko uporabijo v tem posebnem primeru. Podatki so bili zbrani iz različnih virov in ovrednoteni, da bi ustvarili vhodne podatke za modele razdelitve vode in hidravlične modele. Da bi razumeli neravnovesje med ponudbo in povpraševanjem po vodi v različnih pogojih, so bili ustvarjeni trije alternativni scenariji: suho, normalno in mokro letno obdobje. Za oceno vrzeli v povpraševanju in ponudbi na raziskovalnem področju tako za proizvodnjo energije kot za namakanje je bilo uporabljeno programsko orodje Water Evaluation and Planning Model (WEAP). Hidravlični model je bil ustvarjen z uporabo sistema za analizo reke (HEC-RAS) Centra za hidrološki inženiring za določitev globine vode, ki ustreza pretoku, ki ostane v reki po porabi energije in vode za namakanje. Glede potreb po vodi za proizvodnjo energije ugotovitve kažejo, da je april najbolj zadovoljen, september pa najmanj. Pri rabi vode v kmetijstvu ni bilo ugotovljenega primanjkljaja vode, glede na dejstvo, da je razpoložljiva voda v sistemu veliko višja od zahtevane potrebe posevka po vodi (cwr) skozi vse leto. Rezultati hidravličnega modela kažejo, da je globina vode v sušnih letih precej nizka, kar bo negativno vplivalo na plovbo.

Multiple international agreements have emphasised the use of monitoring activities in ecosystems for better conservation of biodiversity and sustainable use of natural resources. Even though the monitoring activities have improved with Earth Observation products, there is still a lack of understanding and research in monitoring ecosystem functions. Primary Productivity (PP) is a process that supports most of the ecosystem functions, and its estimations is a step forward for a better understanding and monitoring of this component of biodiversity. This thesis proposes a workflow and a programming tool to produce empirical models of primary productivity and map Gross Primary Productivity (GPP) and Net Primary Productivity (NPP) in ecosystems at a local scale with high-resolution data. The workflow follows previous research on remote sensing techniques for primary productivity modelling. Specifically, the empirical method described by Cai et al. (2021) is implemented to derive GPP empirical models. A methodology is proposed to upscale the model and compute annual GPP predictions. The annual GPP predictions are finally used to approximate the annual NPP with the Carbon Use Efficiency (CUE) conceptual parameter of the ecosystems reported in previous research. The workflow is applied in a wetland ecosystem in Doñana National Park. Data scarcity in the study area limited the application of the workflow. From the original workflow targets, only a GPP model could be formulated for an 8- month period. The model predicted GPP with high performance deriving MAE = 0.52 gC m-2 day-1, RMSE = 0.63 gC m-2 day-1 and R2 = 0.93. The average 8-month GPP in the monitored ecosystem was estimated at 770.20 gC m-2. The research insights are relevant for future research on monitoring primary productivity in wetland ecosystems with empirical approaches. Especially, the use of the Red-edge Chlorophyll Index formulated with high spectral and high spatial resolution Sentinel-2 data is highlighted for further research on remote sensing modelling of primary productivity. Številne mednarodne zaveze so poudarile pomembnost spremljanja ekoloških razmer različnih ekosistemov z namenom izboljšanja biodiverzitete in trajnostne rabe naravnih virov. Kljub temu, da so se metodologije opazovanja izboljšale, je še vedno precej neznank povezanih z opazovanji in razumevanjem ekosistemskih storitev. Primarna produkcija (PP) je proces, ki podpira večino ekosistemskih storitev, in ocena primarne produkcije je korak k izboljšanju biodiverzitete. V nalogi je predstavljen razvoj metodologije in modeliranje empiričnega modela za primerno produkcijo in karte t.i. bruto primerna produkcije (GPP) in neto primarne produkcije (NPP) v ekosistemih na lokalnem nivoju. Metodologija temelji na zadnjih dognanjih s področja daljinskega zaznavanja. Empirična metoda, ki so jo opisali Cai et al. (2021) je uporabljena kot osnova za določitev GPP modela. Predstavljena je metodologija za izračun letnih vrednosti GPP na večjem območju. Letne vrednosti GPP so uporabljene za oceno NPP vrednosti z upoštevanjem učinkovitosti ogljika (CUE), ki je bil kot parameter upoštevan tudi v predhodnih raziskavah. Metodologija je testirana na primeru mokrišč v nacionalnem parku Doñana. Pokazale so se določene omejitve pri uporabi metodologije predvsem z vidika razpoložljivosti podatkov. Določen je bil GPP za 8-mesečno obdobje. Učinkovitost modela je bila visoka z MAE = 0,52 gC m-2 dan-1, RMSE = 0,63 gC m-2 dan-1 in R2 = 0,93. Povprečen 8-mesečni GPP je bil ocenjen na 770,20 gC m-2. Zaključki raziskave so pomembni z vidika nadaljnjega razvoja določanja primarne produkcije v mokriščih z uporabo empiričnih metod. Posebej uporaba t.i. Red-edge indeksa v kombinaciji s podatki Sentinel-2 se je izkazala kot primerna za nadaljnjo uporabo v podobnih raziskavah.

Flood hazard mapping is an essential component of flood risk assessment, providing valuable information for preventive pre-impact hazard reduction, largely employed in spatial planning, risk management, and raising public awareness about flood hazards. Spatial and temporal variation of the natural processes, limited knowledge about the system's physical properties, and insufficient data introduce uncertainties in the modelling chain used to produce flood inundation and hazard maps, hampering flood risk management. This master’s thesis investigates the impact of uncertainties in hydrological and hydraulic parameterization and the related sensitivity of hydrological and hydraulic calculations and modelling on flood hazard mapping. Specifically, uncertainties related to the flow hydrograph shape and peak discharge value and variations in the channel and floodplain Manning's roughness coefficients were propagated through a combined 1D/2D hydraulic model using LiDAR Digital Terrain Model (DTM) combined with geodesy data of the Vipava river channel and detailed land use data. The uncertainty analysis was applied to the case study of the Vipava river, a transboundary river catchment shared between Slovenia and Italy, by comparing the flood extension and spatial distribution of flood hazard classes by performing hydraulic simulations associated with 10-, 100-, and 500-year return periods as specified in the Slovenian legislation. The analysis points out the greatest sensitivity of the results associated with variations in the channel Manning’s coefficients for a 10-year return period event, depicting an increase in the flood extent of 45%. The increase in the inundated areas is smaller for 100- and 500-year floods, amounting to 15% and 11%, respectively. Furthermore, the modelling results confirm the higher impact of the uncertainty in the peak discharge with respect to the impact of varying floodplain Manning’s values, denoting an increase in the flood extension of 9-12% between the 10% and 90% confidence interval values for the different flood occurrence probabilities. The maximum increase in the flood-prone area with the floodplain Manning’s coefficients amounts to 4-6%. Lastly, the impact of the flow hydrograph shape variations appears to be the lowest, depicting a maximum variation in the flood inundation area of 2-3%. All these changes in the overall flood extent are further reflected in variations of flood hazard classes, which are not uniform and not equally distributed for all but depend on the water depth distribution which is considered the dominant criterion for flood hazard classification. Izdelava kart poplavne nevarnosti je bistvena sestavina v postopku izdelave ocene poplavne ogroženosti, saj zagotavlja ključne informacije za preventivno zmanjševanje poplavne ogroženosti, ki se v veliki meri uporablja pri prostorskem načrtovanju, obvladovanju poplavnih tveganja in ozaveščanju javnosti o nevarnosti poplav. Prostorske in časovne spremembe naravnih procesov, omejeno poznavanje fizikalnih procesov in nezadostni podatki vnašajo negotovosti v proces modeliranja poplavnih dogodkov, ki se uporablja za izdelavo kart obsega poplav in analizo poplavne nevarnosti, kar ovira obvladovanje tveganja zaradi poplav. To magistrsko delo raziskuje vpliv negotovosti v hidrološki in hidravlični parametrizaciji ter s tem povezano občutljivost hidroloških in hidravličnih izračunov in rezultatov modeliranja na kartiranje poplavne nevarnosti. Natančneje je preučen vpliv negotovosti, povezanih z obliko hidrograma pretoka in oceno konice visokovodnega pretoka ter spremenljivostjo vrednosti Manningovega koeficienta hrapavosti struge reke Vipave in poplavnega območja, na rezultate kombiniranega 1D/2D hidravličnega modela z uporabo LiDAR digitalnega modela terena v kombinaciji z geodetskimi podatki rečne struge in podrobnimi podatki o rabi tal. Analiza negotovosti in občutljivosti je bila izdelana za odsek reke Vipave, čezmejne reke, ki teče skozi Slovenijo in Italijo. Izdelana je bila primerjava obsegov poplav in prostorske porazdelitve razredov poplavne nevarnosti s hidravličnimi simulacijami območij razlivanja poplavnih voda povezanih z 10-, 100- in 500-letno povratno dobo, kot jih določa slovenska zakonodaja. Analiza je pokazala največjo občutljivost rezultatov modeliranja na spremenljivost vrednosti Manningovega koeficienta hrapavosti glavne struge v primeru 10-letne povratne dobe, ki se odraža v povečanju obsega poplavljenih površin za 45%. Pri 100- in 500-letnih poplavah je povečanje poplavljenih območij manjše in znaša 15% oziroma 11%. Poleg tega rezultati modeliranja potrjujejo velik vpliv negotovosti pri oceni visokovodne konice pretoka v primerjavi z vplivom spremenljivih vrednosti Manningovega koeficienta hrapavosti na poplavnih območjih. Ugotovljeno je bilo povečanje poplavnega območja za 9-12% ob upoštevanju vrednosti intervala zaupanja 10% in 90% statistično izvrednotenih konic pretokov za različne verjetnosti pojava poplav. V primeru spremenljivih vrednosti koeficientov hrapavosti na poplavnih območjih je bilo povečanje obsega poplavljenih območij 4-6%. Vpliv oblike hidrograma toka se je izkazal kot najmanj pomemben dejavnik pri določitvi obsega poplavljenih površin, spremenljivost obsega poplavljenih površin je znašala 2-3%. Vse zgoraj omenjene spremembe skupnega obsega poplav se odražajo v spremenljivosti prostorskega obsega razredov poplavne nevarnosti, ki niso enotne in enakomerno porazdeljene za vse razrede poplavne nevarnosti, ampak so odvisne od porazdelitev globine vode na poplavnih območjih kot prevladujočega kriterija za razvrščanje v razrede poplavne nevarnosti.

V magistrskem delu je podrobneje predstavljen potek tipične zasnove in sanacije že dotrajanih hidrotehničnih objektov – zaplavnih pregrad na hudourniku Presušnik, ki izvira na južnih pobočjih gorske verige Karavank. Identificirali smo več možnih rešitev in se do njih opredelili. Opisan je postopek, kako opredelimo problem, kjer najprej s slikovnimi prikazi in opisi predstavimo obstoječe stanje in identificiramo kritične točke, na katere moramo biti pozorni pri snovanju rešitve. Zatem smo pripravili in analizirali pomembne vhodne podatke, kot je čas zakasnitve poplavnega vala, analiza ekstremnih padavin, modeliranje površinskega odtoka in podobno. Po končani analizi podatkov, ki so nam bili na voljo, smo lahko določili tri možne pristope k sanaciji, kjer smo pojasnili njihove prednosti in slabosti ter možnost izvedbe. Po pregledu dejavnikov kot je trajnost, varnost in zanesljivost, se je za optimalno rešitev izkazala rušitev starih pregrad in izgradnja novih. Temu v zadnjih poglavjih sledi dimenzioniranje elementov novih pregrad in pomožnih objektov ter umeščanje v prostor. Zasnovo novih objektov prikažemo na skicah in načrtih, izrisanih s pomočjo računalniških programov. Predstavljena je tudi tehnologija gradnje zaplavne pregrade. In the master's thesis we present the process of evaluation, redesign, and reconstruction of heavily damaged hydraulic structures – check dams on torrential Presušnik watercourse, that springs up on southern slopes of Karavanke mountain range. We identified several potential solutions, quantified their applicability to estimate the optimal solution. In the thesis we describe the entire workflow at first, we define and present the existing situation with graphical representations and technical details, followed by identification of critical points that must be considered in the design process. In the next stage we prepared and analyzed the input data, e.g., such as flood wave lag time, extreme rainfall analysis, surface runoff modeling. After completing the analysis of the available data, we were able to determine three possible reconstructions methods, for each of them we identified their advantages, disadvantages, and possible limitations for the construction. After reviewing factors such as durability, safety, and reliability, the optimal solution proved to be the decommissioning of the existing old check dams and the construction of new ones. The final chapters are devoted to the design of new dams and auxiliary structures, stability analysis, and placement of the elements in nature. The design of new buildings is shown on technical drawings, and area plans. In the end we provide the technology of construction for the check dams.

Digiteeritud Euroopa Regionaalarengu Fondi rahastusel, projekti "Eesti teadus- ja õppekirjandus" (2014-2020.12.03.21-0848) raames., https://www.ester.ee/record=b1646501*est

Slugova dolina je primer območja razpršene poselitve, ki se opušča za stalno prebivanje, vendar še naprej uporablja kot vikend destinacija za oddih. Ker se nahaja na vodovarstvenem območju, je za zagotavljanje izpustov v okolje, manjših od predpisanih, potrebna preureditev komunalne infrastrukture – odvajanje in čiščenje odpadnih komunalnih voda ter odstranitev nelegalnega odlagališča odpadkov, ki je tam nastalo v preteklosti. Pri načrtovanju ustreznih rešitev je bil upoštevan tudi vpliv razmočenosti območja in predviden načrt dreniranja terena. Raziskan je bil tudi vpliv plazu Laze na območje Slugove doline in narejena analiza odvisnosti padavinskih podatkov okoliških padavinskih postaj od samodejne meteorološke postaje Blegoš, ki se nahaja neposredno na obravnavanem območju Slugove doline. Sluga Valley is an example of scattered settlement area, which is abandoned for living but continues to be used as a weekend getaway destination. As it is located in a water protection area, in order to ensure permitted discharges into the environment, it is necessary to reorganize the municipal infrastructure - the drainage and cleaning of waste municipal water and the removal of the illegal waste dump that was created there in the past. During the planning suitable solutions, the impact of the wetness of the area was also considered, and planned design for draining the groundwater if necessary. The impact of the Laze landslide on Sluga Valley was also investigated, and an analysis of the rainfall data dependence of the surrounding rainfall stations on the automatic meteorological station Blegoš, which is located directly in the considered area of the Sluga Valley.

V hidrološki praksi se pogosto uporabljajo hidrološki modeli, ki simulirajo površinski odtok in se lahko uporabijo tudi za napovedovanje poplav. Kadar imamo na voljo merjene podatke o padavinah in pretokih, lahko za izdelavo hidrološkega modela uporabimo eno izmed teorij, ki se uporablja za modeliranje, t.j. teorijo hidrograma enote. V praksi pa se pogosto zgodi, da nimamo na voljo vseh podatkov za izdelavo hidrološkega modela in njegovo umerjanje. V tem primeru lahko na podlagi lastnosti porečij oblikujemo sintetični hidrogram enote, ki ga nato uporabimo v postopku hidrološkega modeliranja. V diplomski nalogi smo izbrali dvajset večjih porečij v Sloveniji z znanimi lastnostmi (npr. raba tal, naklon). Za vsako porečje smo zbrali pet največjih dogodkov v obdobju 2000-2020 in posledično na podlagi merjenih padavin in pretokov za vsako porečje določili povprečen čas zakasnitve. Poleg osnovnih lastnosti izbranih porečij, smo jih nekaj, kot je dolžina vodotoka, dolžina vodotoka od profila, ki je najbližji težišču porečja, do iztočnega profila in padec vodotoka, tudi naknadno določili s programom SAGA-GIS. Na podlagi lastnosti porečij smo za posamezno porečje izračunali čas zakasnitve po obstoječih metodah, kot je Snyderjeva metoda, metoda Denver, metoda Tulsa District idr. Omenjene enačbe so bile razvite za območje Združenih držav Amerike, kjer je odziv porečij na padavine lahko drugačen kot v Sloveniji. Posledično je možno sklepati, da bi enačba, razvita na podlagi lastnosti porečij pri nas, podala boljše rezultate hidroloških modelov z vidika ujemanja merjenih in simuliranih pretokov. S tem namenom smo s programskim orodjem R s preizkušanjem več deset različnih primerov enačb, poskušali razviti novo enačbo. Izbrano enačbo, ki je podala najustreznejše rezultate, smo preverili s hidrološkim modelom HEC-HMS, kjer smo uporabili merjene podatke testnega porečja vodotoka Medije. Rezultati so potrdili našo hipotezo, da je enačba razvita na podlagi lastnosti porečij v Sloveniji, ustreznejša. Environmental engineering often uses hydrologic rainfall-runoff models that simulate surface runoff and can be used for flood prediction. One of the methods to set-up hydrologic models is the unit hydrograph theory, which can be used if adequate data about precipitation and discharges is lacking. In practice, sufficient precipitation and discharge data is often not available. In this case, we can obtain results by creating synthetic unit hydrograph, which is based on the characteristics of drainage basins. For the purposes of this graduation thesis we chose twenty larger Slovenian catchments with known characteristics (e.g., land use, slope) and for each catchment five biggest flood events were selected. Based on the characteristics of the catchments we calculated lag time using existing methods such as Synder’s method, Denver method, Tulsa District method, etc. The mentioned equations were developed at the area of the United States of America where the characteristics of the catchments differ from the characteristics of the ones in Slovenia. Consequently, we can conclude that the equation developed based for the catchments in Slovenia could provide more accurate results. With this in mind, we attempted to develop a new equation by testing seventy different cases using R programming language. The selected equation, which gave the most adequate result was further verified with the HEC-HMS hydrological model where we processed data of the additional catchment (i.e. Medija River catchment). The results confirmed our hypothesis, which stated that the equation developed based on the characteristics of the catchments in Slovenia would yield better modelling results.