Glacial sediment is an important paleoclimatological and paleoenvironmental archive. In the Mediterranean region most of the Quaternary glaciers were hosted in carbonate mountains. Diagenetical processes in carbonate sediments tend to impact preservation of glacial features and complicate the establishment of accurate chronologies. This paper presents a sedimentological study of a paleoglacier hosted in the carbonate Velebit Mountain, Croatia. Three carbonate tills were studied in order to evaluate their depositional environments and the diagenetical processes that affect them. The tills were selected from lateral moraines of different glacial stages of the paleoglacier and they are interpreted as lodgement and melt-out tills. Diagenetical processes such as cementation, dissolution and increase in organic content were enhanced by the percolation of water through the sediment and the propagation of rootlets. This research demonstrates the importance of understanding the diagenetical processes affecting carbonate tills after their sedimentation. Studies like this are an essential research stage prior to conducting geochronological and paleoclimatological interpretations based on paleoglaciers in carbonate regions.

Rijeka Krka sa svojim pritocima čini sustav kompozitnih dolina u kršu. Kompozitnost dolina posljedica je litoloških i tektonskih odnosa. Dolina Krke poligenetskog je postanka. Za kanjonske dijelove karakteristična je pojava brojnih padinskih reljefnih detalja. Na strmijim padinama izrazito je osipanje i urušavanje. U aluvijalnim nanosima u dolinskim proširenjima nađeni su fragmenti kršja okolnih stijena. U novije doba uočava se regeneracija vegetacije koja pridonosi promjeni intenziteta modeliranja reljefa egzogenim procesima.Ključne riječi: Rijeka Krka, geomorfološka obilježja, padinski procesi, antropogeni i zoogeni utjecajiThe Krka River and its tributaries make the system of composite valleys in the karst. The composite valley system is the result of lithologic and tectonic relations. The Krka valley is of polygenetic origin. In the canyon sections there are many characteristic slope relief details. On steeper slopes crumbling and collapsing is significant. The debris of surrounding rocks is found in alluvial deposits at the valley widening. In recent times, the regeneration of vegetation is noticeable, which contributes to decreasing intensity of relief shaping by exogenic processes.Key words: Krka River, geomorphologic features, slope processes, anthropogenic and zoogenic influences UvodJedan od najvećih problema Južne Hrvatske je nedostatak vode. Prevlast karbonatnih stijena i njihova tektonska razlomljenost pospješuju poniranje atmosferske vode u podzemlje, dok krajobrazom dominira krš. Upravo stoga pojava vode na površini ima veliko značenje. Kao posljedica kompleksnih međuodnosa litološkog sastava, tektonike, hidroloških značajki i egzogenih procesa u morfološkom smislu u poriječju Krke mogu se izdvojiti tri dijela: planinsko područje na sjeveroistočnom dijelu, dolinska

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The Croatian coastal karst abounds in submerged caves that host a variety of environmental conditions depending on the geomorphology, depth and submarine groundwater discharge. One example is the Y-Cave, a shallow, mostly submerged, horizontal cave on Dugi Otok Island, on the eastern Adriatic coast. This study was aimed at examining the temporal and spatial variability of the marine cave environment, including temperature, salinity, light intensity, cave morphology and hydrodynamism, along with the dissolutional effect caused by the mixing of sea and freshwater. The general distribution of organisms in the Y-Cave was positively correlated to the light gradient and reduced water circulation, thus the highest species diversity and abundance were recorded in the front part of the cave. The phylum Porifera was the most dominant group, and the poriferan species diversity in the cave ranks among the ten highest in the Mediterranean. The middle part of the cave, although completely dark, hosts an abundant population of the gastropod Homalopoma sanguineum and clusters of the gregarious brachiopod Novocrania anomala, whose presence could be connected to tidal hydrodynamics. The absence/scarcity of sessile marine organisms and pronounced corrosion marks at shallow depths inside the cave suggest a freshwater impact in the upper layers of the water column. A year long experiment with carbonate tablets revealed three different, independent ongoing processes affected by the position in the cave: bioaccumulation, dissolution and mechanical erosion. The results of long-term temperature readings also revealed water column stratification within the cave, which was not disturbed by either tidal or wave action. The shallow, partly submerged and relatively small Y-Cave is characterised by a suite of complex environmental conditions, which, together with the resulting distribution of organisms, are unique to this cave.

UDC: 911.53:551.44(262) Branka AniËiÊ & Draaeen Perica: Structural Features of Cultural Landscape in the Karst Area (landscape in transition) During a long historical continuity in the karst area a specific landscape type has evolved due to varied climatic, geomorphological, topographic as well as socioeconomic conditions. This is characterized by great typological diversity based on authentic features both of natural and cultural origin. These have occurred as a consequence of balanced economic land-uses from early periods on. The main quality of these landscapes is derived from unique agricultural land-use patterns, which constitute one of the most valuable spatial heritages in the entire Mediterranean. However, the recent evolution, mainly in the socioeconomic sphere, generated far-reaching impacts in the rural areas which largely affect the integrity and traditional harmony the karst countryside in general and the landscape in particular. The basic intention of the paper is to outline these transformations as a serious threat and immense loss of the national cultural heritage and to emphasize the great responsibility of this generation in these processes.