The gully of Potovošća on the island of Krk – The effects of a short-term rainfall event

The rainfall event during the night of 10th–11th September 2007 caused strong erosion in the gully of Potovošća on the Island of Krk. In the main fan, two new gullies and two fans were formed. Those morphological changes have been mapped, measured and explained, across the drainage basin in terms of topography and precipitation intensity. The drainage basin morphology was studied using GIS that allowed comparison of morphological and dynamic relationships within the study area. In order to obtain the relative potential erosion intensity between different points in the basin, as well as to differentiate areas with areal (diffuse) erosion from those with dominant linear erosion, the Stream Power Index (SPI) was calculated. The drainage basin specific properties were further related to the event specific properties, precipitation intensity and hydrologic estimations. The rainfall intensities obtained, allow the calculation of discharge at the gully mouth and the definition of recurrent periods using the rational method. The rainfall-runoff event studied was also influenced by the relatively high Antecedent Precipitation Index (API). This allows explanation of the morphological consequences of the short-term event. Consequently the interrelationship between short-term and long-term events has been discussed. In addition, the physiography of the gully has been recently modified by human interference, which has also influenced the morphological consequences of the aforementioned short-term rainfall event.</p

Marko Zečević. 2017. Uvod u vojnu geologiju. Zagreb, Hrvatsko vojno učilište „Dr. Franjo Tuđman”. 57 str.

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Digital analysis of the slopes of Rab Island

U radu su analizirana morfometrijska obilježja padina otoka Raba. Na temelju formiranoga digitalnog modela reljefa izračunati su rasterski slojevi vrijednosti nagiba, ekspozicije i zakrivljenosti padina, te dolinska mreža koja je grupirana prema metodi Strahela. U GIS okružju provedena je međusobna analiza izračunatih vrijednosti morfometrijskih parametara. Prostorni raspored vrijednosti pojedinih morfometrijskih parametara doveden je u vezu sa strukturnim i morfogenetskim obilježjima otoka Raba. Utvrđene su razlike obilježja padina unutar pojedinih morfogenetskih tipova reljefa, kako na temelju samih morfometrijskih obilježja, tako i analizom dolinske mreže.The paper analyzes morphometric features of the slopes of Rab Island. Based on the digital elevation model, raster layers were calculated for the values of slope angle, aspect and curvature, as well as valley network, which was grouped using the Strahler method. A comparative analysis of the calculated values of morphometric parameters was conducted in the GIS environment. Spatial distribution of the values of each of the morphometric parameters was correlated to the structural and morphogenetic features of Rab Island. Differences between the slopes features within each of the morphogenetic types of the terrain were ascertained by comparing their morphometric features, and by using the valley network analysis

Spatial Distribution and Density of Dolines in the NW Part of Velika Kapela from GIS Based Buffer Analysis

Primjenom metoda GIS-a temeljenih na analizi susjedstva promatran je prostorni raspored i gustoća ponikava u SZ dijelu Velike Kapele. Rezultati dobiveni analizom formiranih prostornih baza podataka ukazuju na prostorni raspored pukotina odnosno rasjeda, ali i intenzitet veze između pružanja i gustoće ponikava, te utvrđenih lineamenata. Usporedbom rasjeda određenih temeljem analize ponikava, sa rasjedima vidljivih na digitalnom modelu reljefa (DEM), te rasjedima uočenim terenskim kartiranjem određene su temeljne tektonske cjeline, odnosno tektonski blokovi unutar istraživanog područja. Veći regionalni i lokalni rasjedi determinirani na digitalnom modelu reljefa odvajaju pojedine tektonske cjeline, dok manji lokalni rasjedi izvedeni na temelju linearno razvijenih ponikava, uglavnom razdvajaju manje tektonske blokove, te ukazuju na deformacije i ispucanost pojedinog bloka.GIS based buffer analysis methods were applied for analysing spatial distribution and density of dolinas in the NW part of Velika Kapela. Results extracted from existing spatial databases indicated spatial distribution of faults, as well as a degree of relationship between direction and density of dolinas with identified lineaments. By comparing faults identified from dolina analysis, with faults identified during on-situ mapping, major tectonic blocks or units within researched area were identified. Bigger regional and local faults identified from digital elevation model are dividing larger tectonic units, while smaller local faults derived from linearly developed dolina are mostly dividing smaller tectonic blocks and can indicate their degree of faultness and deformities

Marko Zečević. 2017. Uvod u vojnu geologiju. Zagreb, Hrvatsko vojno učilište „Dr. Franjo Tuđman”. 57 str.

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Spatial Density of Dolines in the Croatian Territory

Cilj je ovog rada utvrditi prostornu gustoću ponikava na području krša Hrvatske i provesti korelaciju izračunatih vrijednosti gustoće ponikava s pojedinim geomorfološkim i geološkim čimbenicima njihova nastanka i razvoja. Kako bi se to postiglo, potrebno je izračunati prostornu gustoću ponikava temeljem jedinstvenih GIS metoda prikupljanja i analize podataka unutar čitavoga istraživanog područja. Gustoća ponikava unutar jedinične površne izračunata je na temelju kartiranih dna ponikava. Za potrebe određivanja dna ponikava upotrijebljene su digitalne kartografske podloge u mjerilu 1 : 25.000. Na temelju dobivenih podataka izračunata je prostorna gustoća ponikava jednostavnom kernel metodom unutar površine od 1 km2. Provedenom analizom prostornih razlika u intenzitetu gustoće ponikava, uočene su pojedine veze između njihova razvoja i morfometrijskih parametara reljefa, te litoloških i strukturnih obilježja terena.This paper deals with the spatial density of dolines in the Croatian territory covered by karst. The purpose of this paper is to calculate the spatial density of dolines and show a correlation between calculated doline density values and certain geomorphological and geological factors of their origin and development. Therefore, it has been necessary to calculate the spatial density of dolines applying unique GIS methods of data collection and analysis to the entire study area. Doline density per unit area has been calculated based on the mapped doline bottom. 1:25,000 scale digital cartographic models have been used to determine the doline bottom. The given data have been used to calculate the spatial density of dolines applying a simple kernel method to an area of one square kilometre. The analysis of spatial differences in doline density has revealed that certain connections exist between doline development and relief morphometric parameters as well as lithological and structural terrain features

Climate and relief influence on the carbonate surface corrosion intensity int he Velika Kapela mountain group

Istraživanje intenziteta površinske korozije u području gorske skupine Velike Kapele provedeno je metodom ¨standardnih vapnenačkih tableta¨. Kako spomenuta metoda ukazuje na zavisnost korozije i klimatskih elemenata izračunati su vertikalni gradijenti padalina za privjetrinske i zavjetrinske klimatološke stanice, te temperaturni vertikalni gradijenti u istraživanom prostoru. Eksponencijalnom korelacijskom analizom određena je međuzavisnost intenziteta korozije, kako gole vapnenačke površine, tako i subkutane korozije sa nadmorskom visinom, odnosno količinom prosječnih godišnjih padalina i temperaturom zraka.The research of surface corrosion in the area of Velika Kapela mountain group was performed by the method of standard limestone tablets. Since this method points at interdependence between corrosion and climatic elements, the perticipation vertical gradient for the windward and leeward located meteorological stations and temperature vertical gradient in the research area were calculated. Using the exponential correlation analysis, the interdependence between the corrosion intensity (on bare limestone surface and subcutaneous corrosion) and altitude, respectively the annual precipitation and temperatures was determined

Physical-geographic factors of terrain trafficability of military vehicles according to Western World methodologies

U ovom se radu analizira postojeće stanje, ograničenja i mogućnosti istraživanja fizičko-geografskih čimbenika u kontekstu terenske prohodnosti vojnih vozila u svrhu potpore procesa donošenja vojnih odluka prilikom planiranja pokreta vojnih snaga. Rad prikazuje do sada korištene tipove modela, metodologije i načine prikaza rezultata utjecaja fizičko-geografskih čimbenika na pokretljivost vozila. Provedena istraživanja pokazala su da je u dosadašnjim istraživanjima najčešće korišten parametar nagib padina, potom fizičke osobine tla, hrapavost površine vodotoci, tipovi vegetacije i klimatsko-meteorološki uvjeti. Kvaliteta rezultata dosadašnjih istraživanja određena je kvalitetom i točnošću ulaznih podataka te primjenjivanim metodama korištenima u modelima. U novijim istraživanjima geografski informacijski sustav (GIS) autorima omogućuje sjedinjavanje cjelokupne problematike utvrđivanja terenske prohodnosti vozila jer objedinjuje sve mogućnosti na jedinstvenoj platformi.This paper analyses the existing state, limitations, and possibilities for research of physical-geographic factors in the context of terrain trafficability of military vehicles in order to support the military decision-making process regarding planning movements of military forces. This paper shows which models and research methodologies were used to ascertain how physical-geographical factors influence vehicle cross-country mobility. Research has shown that slope has been used most frequently as a parameter, followed by soil properties, surface roughness, watercourses, vegetation types, and climatic-meteorological conditions. The quality of the results achieved so far has been largely determined by the quality and accuracy of the input data and by the various methods used in the models. Recent studies have shown that the Geographic Information System (GIS) unifies the issues determining vehicle terrain trafficability, as it displays all possibilities in a single platform

Primjena geomorfoloških istraživanja u vojnoj analizi terena - indeks zaštitnog potencijala reljefa

Primjena geomorfoloških istraživanja u vojnoj analizi reljefa, temeljena na GIS me¬todama prostorne analize, vezana je u prvom redu za vojno geografsku prosudbu prostora. Pri tom se podrazumijeva vrednovanje reljefa s obzirom na neposredni učinak, kako na premještanje snaga, manevar, preglednost, tako i na mogućnost zaštite i maskiranja. Pro¬vedena analiza vrednovanja zemljišta unutar dijela vojnog poligona «Slunj», uključila je definiranje boniteta kategorija reljefa s obzirom na mogućnost zaštite i prikrivanja u cilju uvrštavanja geomorfološke osnovice u standardnu vojnu proceduru OCOKA (Observation and fields of fires; Cover and concealment; Obstacles and movement; Key terrain; Avenus of approach). Definirani model prostorne analize terena uključio je pet parametara reljefa (vidljivost, konkavne elemente reljefa, ekspoziciju padina, gustoću ponikava i dolina unutar jedinične površine) koji u znatnoj mjeri utječu na mogućnost zaštite i prikrivanja. Morfo¬metrijski podaci uključeni u pojedine bonitetne kategorije određeni su temeljem analize digitalnog modela reljefa primjenom GIS alata i postavljenih morfometrijskih metoda istraživanja reljefa. Na temelju postavljenog modela izračunati su parametri i izrađena je karta potencijalne zaštite i prikrivenosti, unutar pilot područja vojnog poligona «Slunj»

Geomorphological heritage of the significant landscape Risovac - Grabovača

Značajni krajobraz Risovac - Grabovača kraj Perušića u Lici geomorfološki i speleološki je interesantno područje s brojnim estetskim, znanstvenim i obrazovnim vrijednostima. U sklopu projekta temeljnih geomorfoloških i speleoloških istraživanja, bez kojih nije moguće kvalitetno vrednovati georaznolikost i geobaštinu, korištene su morfometrijske i morfogenetske metode te metode speleoloških istraživanja. Cilj istraživanja bio je inventarizirati i analizirati geomorfološke pojave i procese u postupku ocjene stanja te kao polazište za vrednovanje radi kvalitetnog upravljanja i zaštite geobaštine. Temeljem hipsometrijskih odnosa izdvojene su morfografske reljefne cjeline. Definirane su i glavne morfostrukturne cjeline. Na istraživanom području prevladavaju krški i fluviokrški reljef s brojnim površinskim i podzemnim reljefnim oblicima. Brojni su i elementi antropogenog reljefa. Od reljefnih oblika detaljnije su analizirane ponikve i speleološki objekti kao najbrojnije i najinteresantnije pojave velikog geoturističkog potencijala.The Significant landscape Risovac - Grabovača near Perušić in Lika is a geomorphologically and speleologically interesting area with numerous aesthetic, scientific and educational values. As part of the project of basic geomorphological and speleological research, without which it is not possible to qualitatively evaluate geodiversity and geoheritage, morphometric and morphogenetic methods and methods of speleological research were used. The aim of the research was to inventory and analyze geomorphological phenomena and processes within the condition assessment and as a starting point for evaluation for quality management and protection of geoheritage. Based on hypsometric relationships, morphographic relief units were singled out. The main morphostructural units are also defined. Karst and fluviokarst relief with numerous surface and underground relief forms prevails in the investigated area. There are also numerous elements of anthropogenic relief. The dolines and caves as the most numerous and most interesting phenomena of great geotourism potential have been analyzed in more detail