Geomorphological features of the river Šuijca valley

Rijeka Šujica je krška ponornica u zapadnoj Hercegovini koja protječe kroz krško polje (Duvanjsko polje) i dolinsko proširenje rijeke Šujice (Šujičko polje), te tako čini kompozitnu dolinu. Dolina rijeke Šujice bogata je krškim oblicima. Krški reljef ovog područja oblikovan je egzogenim fluvijalnim procesima i procesima okršavanja karbonatnih stijena koje grade ovo područje. Cilj ovog rada bio je istražiti geomorfološke oblike koji se javljaju duž doline rijeke Šujice. Opisani su i utvrđeni egzogeni procesi koji su doveli do oblikovanja pojedinih dijelova toka rijeke Šujice. Korištenjem postojeće literature i karata prikupljeni su potrebni podatci o prijašnjim istraživanjima i stanju terena. Terenskim radom i fotodokumentacijom utvrdilo se trenutno stanje, te geomorfološke značajke koje su bitne za istraživano područje. Utvrđeno je da su geomorfološki cjeline i oblici doline rijeke Šujice nastali pod utjecajem geoloških i hidroloških čimbenika koji su karakteristični za krška područja. Rijeka Šujica je tipična krška ponornica i njen tok ovisi o oborinama i podzemnim vodama. Cijela dolina rijeke Šujice bogata je krškim oblicima. Izvori Veliki Stržanj i Mali Stržanj su preljevni izvori koji tijekom ljetnih mjeseci presuše. Rijeka Šujica zbog nagiba podloge dolinskih proširenja meandrira, a spajanjem meandara rijeka dobiva novi tok, dok u zimskim mjesecima doline rijeke Šujice zbog velike količine oborina plave. Kanjon rijeke Šujice većinom ima strme strane, a na nekim mjestima čak i približno okomite na dno rijeke. Rijeka meandrira i Duvanjskim poljem te prolazeći kroz blagi kanjon ponire u ponoru Kovači gdje ide u podzemlje te se ponovno pojavljuje na izvoru Ričine.River Šujica is a karst abyss in western Herzegovina that flows through Krško Polje (Duvanjsko Polje) and the valley extension of the Šujica river (Šujicka Polje), making a composite valley. The Šujica river valley is rich in karst formations. The karst relief of this area is shaped by exogenous fluvial processes and karstification of carbonate rocks that build this area. The aim of this work was to investigate the geomorphological forms that occur along the Šujica river valley. The exogenous processes that led to the shaping of certain parts of the Šujica river course are described and determined. By using the existing literature and maps, the necessary data on previous research and the state of the terrain were collected. Field work and photo documentation were done in order to determine the current state and geomorphological features that are important for the researched area. Results show that the geomorphological features of the Šujica river valley were created under the influence of geological and hydrological factors that are characteristic of karst areas. The river Šujica is a typical karst sinkhole river and its flow depends on precipitation and groundwater. The entire valley of the river Šujica is rich in karst forms. The springs Veliki Stržanj and Mali Stržanj are overflow springs that dry up during the summer months. The river Šujica meanders due to the slope of the base of the valley, and by joining the meanders the river acquires a new flow, while in the winter months the valley of the river Šujica is being flooded due to the large amount of precipitation. The canyon of the river Šujica mostly has steep sides, and in some places even approximately perpendicular to the bottom of the river. The river also meanders through the Duvanjsko polje and, passing through a gentle canyon, plunges into the Kovača abyss, where it goes underground and reappears at the source of Ričina