On 2D and 3D parameter derivatio n for r ainfall- r unoff models

Geoinformation technology, particularly GIS and digital terrain models, is commonly used at present in order to derive parameters of basins and flow paths. These parameters are subsequently used to create spatially based rainfall-runoff models. In line with the development of geoinformation technologies such models can be derived both in 2D and 3D formats. The question remains whether the 3D format is suitable for all parameters. In order to solve the question two basic parameters that will be affected by the derivation method were selected. One of them, the Subbasin Area parameter, is essential for the calculation of the precipitation volume for a given subbasin area and subsequently for the calculation of the runoff volume. This parameter is directly dependent on the chosen derivation method since the difference in areas derived in 2D and 3D formats depends on the area gradient. The other parameter, River Length, is important for the modelling of water motion within a stream as it influences the shape of hydrograph a nd the size of culmination discharge. Similarly to the first parameter, it is dependent on the area gradient and thus on the used derivation method. A semi-distributed model of the Lubina River basin in the HEC-HMS environment was chosen to represent spatially based rainfall-runoff models. The model was createdon the basis of ZABAGED hypsometry data.Suitability of the use of parameters derived in the 3D formatfor rainfall-runoff modelling is discussed in the concluding partof the paper

Možnosti propojení GIS a environmentálních modelů pro potřeby krizového řízení a ochrany přírody

Import 22/11/2010Prezenční541 - Institut geologického inženýrstvíNeuveden

Regionální systém varování před povodněmi

Natural disasters have occurred for a very long time, virtually on all continents, and it is obvious that in the areas where human’s social, economic and cultural activities are concentrated, their impacts are more severe. The Laboratory for Modelling and Simulations of Hazardous Situations, operating at the VSB-Technical University of Ostrava, works on a long-term basis on a project called FLOods REcognition On the Net (FLOREON) aimed at development (to meet the needs of the Moravian-Silesian Region) a system for modelling, simulating, monitoring and if appropriate even predicting crisis situations caused by both adverse natural, and possibly human effect. The paper describes principles which the FLOREON system is built on, a conception of the entire system and the first results achieved. In conclusion its further development is outlined, and focused on an extension of the system by next hazardous phenomena such as the modelling of dangerous substance leakage, monitoring of traffic situations and others. So a system occurs denoted as FLOREON+. The plus sign in the name means the system will deal not only with floods, but also with other phenomena in the territory.Přírodní extrémy se objevují od nepaměti, prakticky na všech kontinentech, a pokud zasáhnou oblasti, kde se koncentrují ekonomické, sociální nebo kulturní aktivity lidí, mohou být jejich dopady velice vážné. Laboratoř pro modelování a simulaci krizových situací na Vysoké škole báňské – Technické univerzitě Ostrava pracuje na dlouhodobém projektu nazvaném FLOREON (FLOods REcognition On the Net) a zaměřeném na vývoj systému pro monitorování, modelování, simulaci a pokud to bude možné, tak i predikci krizových situací, způsobených jak nepříznivými přírodními, případně i lidskými vlivy. Článek popisuje principy, na nichž je systém FLOREON budován, koncepci celého systému a první dosažené výsledky. V závěru je nastíněn jeho další rozvoj, zaměřený na rozšíření o další krizové jevy, jako je modelování úniků nebezpečných látek, monitorování dopravní situace a další. Rozšířený systém je označován jako FLOREON+. Znaménko plus v názvu vyjadřuje, že systém již nebude pracovat jen s povodněmi, ale i s dalšími jevy v území

Využití GIS a hydrologických modelů v managementu povodí

919

Modelování vlivu lesa na srážkoodtokové vztahy a vodní erozi s pomocí GIS

22523

Modelování transportu sedimentů v povodí pomocí dynamického erozního modelu ArcSWAT 2005 na příkladu povodí Ostravice

Soil is one of the most important natural sources on earth. The same way as all parts of the environment, and the global ecosystem generally, it suffers from several kinds of human activities in the landscape. One of the most serious environmental problems of our present days is accelerated soil erosion and related processes. In the past, the most of soil erosion studies and researches took place in the field, on experimental plots or in laboratories. The problem of these studies is the fact that they take quite a long time and are expensive. Nowadays, in the age of computers and information technologies, the soil erosion and sediment transport studies can be managed by new effective tools – numerical models. There are lots of numerical models being able to solve several tasks in the field of soil erosion and sediments. One of the most complex numerical models is the SWAT model (Soil and Water Assessment Tool). This physically based semi-distributed model can be used to analyze the complex watershed management and soil erosion, and sediment transport is only a fraction of the tools offered by the model. The main goal of this contribution is to introduce the basic abilities of the model as a tool of soil erosion analyses and sediment transport in watersheds.Eroze půdy, zejména ve své akcelerované podobě, patří mezi nejzávaţnější problémy spojené s aktivitou člověka v krajině a v souvislosti s tempem růstu světové civilizace a nerovnoměrným rozmístěním zdrojů na Zemi je tato hrozba čím dál naléhavější. Člověk se o půdu, jakoţto základní zdoj, zajímal jiţ od samotného vzniku zemědělské společnosti, tedy i poznání v oblasti eroze půdy si prošlo dlouhým obdobím bádání. V dnešní době tak v návaznosti na prudký rozvoj jiných oborů, zejména IT, disponujeme pestrou paletou numerických modelů řešících erozi půdy. Jedním takovým je i právě model SWAT (Soil and Water Assesment Tool). Jedná se o fyzikálně podloţený semidistribuovaný kontinuální dynamický model poskytující řadu nástrojů pro řešení poměrně obsáhlé problematiky managementu povodí, zejména pak s ohledem na vodní sloţku, erozi půdy a rostlinnou produkci. Nápní tohoto příspěvku je pak testování nabídky modelu v oblasti eroze půdy a transportu sedimentů a na ně vázaných látek v povodí. Model byl testován na schematizovaném povodí Ostravice

Modeling of the land cover impact on the rainfall-runoff relations in the Olse catchment

The impacts of land use and land cover on the transformation of the rainfall-runoff episodes were studied and analyzed with the utilization of HYDROG and HEC-HMS rainfall-runoff models in the Olse basin. Two episodes were selected – common regional rainfall with low antecedent watershed saturation and convective flash rainfall with higher watershed saturation. Watershed response was studied and modeled on separate levels of the forestation – actual forestation state, 50 % of forest land cover and 100 % of forest land cover. Results which were achieved with the utilization of the various methods of the hydrologic transformation in the watershed scale (Horton, SCS-CN) confirm the influence of forest land cover on the rainfall-runoff relations Further research with the support of another methods and the continuous models such as GSSHA and MIKE SHE will allow the comparison of achieved results and possible generalization of them

Proposal for risk analysis of the selected floodplain Torysa River Basin

Príspevok sa venuje návrhu analýzy rizík pre vybrané záplavové územie z hľadiska systematického prístupu dostupných kvantitatívnych a kvalitatívnych metód vo vzťahu k analýze rizík. Na vybranom predmetnom území sú posudzované limitujúce faktory, ktoré vykazujú priamy vplyv na vznik povodňovej aktivity záujmového prostredia v zastavenej časti mesta Prešov, povodia rieky Torysa. Nakoľko riziko ako také zväčša nie je izolovanou funkciou, konvenčne ide o kombináciu ďalších rizík preto, ich vzájomný vplyv môže predstavovať pre posudzované územie z hľadiska jeho náchylnosti na vznik povodňovej udalosti bezprostrednú hrozbu. Povodne v poslednej dobe reflektujú najväčšie priame nebezpečenstvo v oblasti prírodných katastrof a sú príčinou závažných krízových situácií. Vzhľadom k množstvu rizík je potrebné exaktne určiť priority z pohľadu dopadu (vplyv na životné prostredie) a mieru pravdepodobnosti ich výskytu. V protipovodňovom procese je isté, že absolútnu ochranu pred vznikom povodní nie je možné dosiahnuť. Integráciou postupnosti jednotlivých krokov procesu priebehu analýzy rizík v značnej miere prispejeme k vytvoreniu územnej bezpečnosti súvisiacej s celkovou protipovodňovou ochranou prírody a krajiny.The article discusses the risk analysis draft of selected flood zone in terms of systematic approach to available quantitative and qualitative methods. The limiting factors of assessed area considered, have direct influence for formation of flood activity of a given environment, for example, a part of the river Torysa. Because the risk generally is not an isolated function, conventionally it is a combination of other risks. Mutual influence of risks can represent threat to assessed territory in terms of susceptibility to formation of fl ood events. Floods in recent years reflect the direct risk of natural disasters and cause major emergencies. Due to the large amount of risks, it is necessary to precisely determine the priorities in terms of impact (environmental impact) and the probability rate of occurrence. It is certain that the absolute protection against floods cannot be achieved. Integration of process steps of risk analysis will largely contribute to the establishment of territorial security associated with the overall flood protection of nature and landscape

Analysis of the impact of land cover spatial structure change on the erosion processes in the catchment

Soil erosion is one of the main environmental problems of this time. Erosion in its recent accelerated form is the reflection of the human activities in the landscape. Soil erosion is a complicated process. Its behaviour and final rate are results of an interaction of whole group of factors. One of these factors is the character of land cover whose main role in the erosion process consists in its protective function. Intensive land use do not dispense with the land cover change and the change of its spatial distribution thus the main content of this contribution is the study of the influence of the land cover change on the erosion processes in the catchment. To quantify that the dynamic erosion SWAT model was used together with the GIS tools. As a study area the Stonavka river catchment was chosen and the erosion processes were analysed using the three CORINE Land Cover layers (specifically CORINE Land Cover of the years 1990, 2000 and 2006) as a model input. The outputs of the analyses in the form of average annual specific sediment loss from the catchment were relativized to the reference years 1990 and following 2000 and were cartographically visualized in the form of cartograms.Web of Science15427626

Effects of LIDAR DEM resolution in hydrodynamic modelling: model sensitivity for cross-sections

With the development of science and technology the entire Earth, together with all of its phenomena, is gradually becoming an object of computer digitisation. For several years, this process has also affected water components, which are essential for the development of humans and economies on Earth. Therefore, monitoring of its resources and movement across the Earth's surface is the main object of investigation of several research institutions. In recent years, hydraulic modelling has experienced significant development that meets water and computer connection conditions. This study consequently dealt with hydraulic modelling and uncertainties in the data that may affect the resulting flood zone. We analysed the effect of cross-sections generated and the subsequent inundation areas in Digital Elevation Models of different resolutions. The basic DEM was constructed from data obtained by the LIDAR method. Hydraulic results were obtained using a one-dimensional (1-D) model, HEC-RAS, and its extension, HEC-GeoRAS. The Olše and Stonávka river junction, located in the northeast region of the Czech Republic, was selected for investigation. The resolutions selected for the study to generate cross-sections and the subsequent inundation areas were 1 m, 5 m and 10 m. The resulting cross-sections were confronted with the actual surveyed cross-sections.Web of Science6127