Kristina Krklec | University of Zagreb Faculty of Agriculture (original) (raw)

Papers by Kristina Krklec

This study presents the comparison of morphometry of karren features developed on two rock surfac... more This study presents the comparison of morphometry of karren features developed on two rock surfaces located side by side having different exposure times. Cosmogenic 36 Cl analyses were used to determine the age of a rock surface exposed after a rockslide that occurred ~2400 years ago, whereas the rock surface not affected by the slide was exposed to weathering for a longer time period. Clint and grikes, trittkarren, rillenkarren, solution pits, and kamenitzas were measured. Comparatively less density of grikes on the surface affected by the slide made it having a fresh appearance. Most of the grikes were inherited from previous weathering stage and exposure time since the rockslide event has not been sufficient to homogenize these features between both rock surfaces. Tritkarren and rillenkarren were preferentially found on the rockslide surface indicating that their genesis is likely to occur at decadal to centennial timescale. Solution pits and kamenitzas were found on both surfaces and some of their size parameters were indistinguishable between the populations of both rock surfaces. Area and depth parameters of both forms were clearly correlated and we define a morphometric index: A/D ratio as the slope between these two parameters within each population. After an initial stage, preferential weathering occurs along the vertical axis in solution pits and laterally in kamenitzas. Thus, we suggest that the A/D ratio is related to the evolution/relative age of the karren features. Thus, under rock surfaces affected by the same weathering conditions, lower A/D ratios of solution pits and higher A/D ratios of kamenitzas indicate longer time exposed to weathering. Thus, although solution pits and kamenitzas are likely to be developed in decadal to centennial timescales, their morphology changes through time at millennial timescale and it can be tracked by morphometric analysis.

Geochimica et cosmochimica acta, 2014

The 5-day reconstruction of air mass history for the days with precipitation at Eagle Cave (centr... more The 5-day reconstruction of air mass history for the days with precipitation at Eagle Cave (central Spain), together with the determination of moisture uptake locations along back trajectories, is used to identify the moisture sources of precipitation for this site from 2009 to 2011. During this 3-year period, around 30% of precipitation at Eagle Cave originated from the moisture recycled within the Iberian Peninsula (IP), with the Proximal Atlantic being also a main source region of moisture, whereas the Mediterranean Sea and the Distal Atlantic have large variability during the studied period and other source regions are minor precipitation contributors. The comparison of monthly oxygen isotope composition of precipitation at Eagle Cave with the monthly percentage of precipitation originated in source regions shows a significant negative correlation for the IP region. Thus, the moisture recycling process in the IP region explains 12% of the variability of the monthly oxygen isotope composition of precipitation (p-value < 0.1). However, when temperature, amount of precipitation and all source regions are considered, 74% of the variability of the monthly oxygen isotope composition of precipitation is explained (p-value < 0.05). Therefore, although for Eagle Cave amount of precipitation and temperature are main contributors of the precipitation oxygen
isotope variability (r2 = 0.54; p-value < 0.001), the moisture uptake distribution among source regions is a substantial control and should be considered when interpreting oxygen isotope speleothem records from this cave. This research highlights the importance of moisture sources in controlling the oxygen isotope composition of precipitation in mid-latitudes, and the need of quantification of this effect in order to improve the interpretation of oxygen isotope paleo-records that depend on isotope composition of precipitation.

Palaeogeography, Palaeoclimatology, Palaeoecology, 2015

Glacial sediment is an important paleoclimatological and paleoenvironmental archive. In the Medit... more 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 tillswere selected fromlateralmoraines 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.

This research focuses on the mechanisms that transfer the variations in surface atmospheric temp... more This research focuses on the mechanisms that transfer the variations in surface atmospheric temperature into caves to evaluate whether they record the warming trend of recent decades. As a study case, we use the data from a hall in Postojna Cave (Slovenia), which was monitored from 2009 to 2013. The low-frequency thermal variability of this cave chamber is dominated by the conduction of heat from the surface through the bedrock. We implemented a thermal conduction model that reproduces low-frequency thermal gradients similar to those measured in the cave. At the 37 m depth of this chamber, the model confirms that the bedrock is already recording the local expression of global warming with a delay of 20–25 years, and predicts a cave warming during the coming decades with a mean rate of 0.015 ± 0.004 C year-1. However, because of the transfer of surface atmosphere thermal variability depends on the duration of the oscillations, the thermal anomalies with periods 7–15 years in duration have delay times\10 years at the studied hall. The interannual variability of the surface atmospheric temperature is recorded in this cave hall, although due to the different delay and amplitude attenuation that depends on the duration of the anomalies, the cave temperature signal differs significantly from that at the surface. As the depth of the cave is a major factor in thermal conduction, this is a principal control on whether or not a cave has already recorded the onset of global warming.

Acta Carsologica / Karsoslovni Zbornik, 2013

This paper focuses on the evolution and patterns of microscale weathering forms and dissolution r... more This paper focuses on the evolution and patterns of microscale weathering forms and dissolution rates of "standard" (Lipica) limestone tablets. Analysis of carbonate weathering using com bination of methods (quantitative analysis by the weight loss of "standard" tablets, and qualitative analysis of the weathered surfaces by stained acetate peels and SEM imaging) showed that dissolution takes place not only at the surface of limestone tablets, but also along voids and cavities in limestone tablets which makes total weathering surface larger than the area of the tablet surface. Dissolution is more pronounced on the mi critic calcite surfaces (due to different dissolution kinetics of carbonate minerals), resulting in lowering of the surface (cal cite matrix) which causes gradual unburial and removal of authigenic dolomite grains.

Acta geographica Slovenica, 2011

Agricultural landscapes that resulted from many centuries of traditional agricultural cultivation... more Agricultural landscapes that resulted from many centuries of traditional agricultural cultivation are an important part of the cultural heritage in the European Mediterranean areas. Since a systematic study in the Republic of Croatia aimed at inventarisation and protection of cultural landscapes has not been carried out yet, the main purpose of this paper was to, based on a case study that took place on the island of Krk, show the method of agricultural landscape evaluation and possibilities for future development and protection of outstanding agricultural landscapes. The evaluation of all 12 identified agricultural landscape types was conducted and six of them were singled out as outstanding cultural landscapes. Possible
structural changes of those landscapes were considered and a proposal for a strategy of the preservation of the valuable landscape heritage on the island of Krk has been formulated. It was concluded that for field landscapes, the preservation is possible through agricultural production modernization. Those outstanding agricultural landscapes that are not profitable, but have a great cultural and historical value, should be maintained through regular procedures for cultural monuments with 100% subsidy.

Annales, Series historia et sociologia, 2013

This paper deals with analysis of the dry stonewall network structural features and their relatio... more This paper deals with analysis of the dry stonewall network structural features and their relationship with the natural landscape. Thus, specific approach was applied – elements of dry stonewall network are analyzed within previously determined spatial units (geocomplex types) that are defined by their internal vertical structure. Based on this set of relations, it is possible to reconstruct the spatial distribution and characteristics of the areas under impact of anthropopression which directly affected the degree of fragmentation and diversity. Landscape metrics (indicators of the composition and configuration of the landscape) was applied in analysis of dry stonewalls structure. Several basic research objectives were set: a) to determine the characteristics of size of dry stonewall network and to select landscape indicators that are most appropriate to define its structure, b) to determine the basic features of the dimension of landscape elements (geocomplex types) within which p...

Geodetski List, 2013

This research is based on application of landscape metrics in GIS environment for determination o... more This research is based on application of landscape metrics in GIS environment for determination of the basic features of horizontal landscape structure of the southern part of Vis island. Landscape elements (or geocomplex types) are determined based on their abiotic (lithological and geomorphological features) and biotic elements (natural vegetation cover). Anthropogenic impact during historical-geographic development (agriculturally cultivated land and urbanized areas) are also considered. By means of GIS tools, the three layers of abiotic and biotic parameters were overlayed (lithology, slope inclinations and types of vegetation cover) and 2556 basic units (geocomplexes) were obtained. Generalization of this basic units by criterion of similarity enabled extraction of 132 types of geocomplexes. This types represent generalised homogenous spatial units which were basis for all further analyses. In the next phase, landscape metrics has been applied in order to determine basic charac...

Veli Rat, 2013

U ovom radu provedena je detaljna analiza geomorfoloških odnosno geomorfometrijskih značajki kao ... more U ovom radu provedena je detaljna analiza geomorfoloških odnosno geomorfometrijskih značajki kao njihovog reprezentanta i njihovog međuodnosa s elementima tradicionalnog kulturnog krajobraza suhozida šireg područja Velog Rata. Ta dva aspekta tijekom historijsko-geografskog razvoja bila su nerazdvojivo i uzročno-posljedično povezana, što se odrazilo na današnji izgled krajobraza ovog područja. Problematika je analizirana na razini istraživanog područja u cjelini te na nižim razinama naselja Veli Rat, Verunić i dijela naselja Soline, radi usporedbe i preciznije interpretacije dobivenih rezultata.

Zbornik radova 45. hrvatskog i 5. međunarodnog simpozija agronoma., 2010

Cilj ovog rada je vrjednovati zemljište za izgradnju golf terena u Barbarigi. U tu svrhu primjenj... more Cilj ovog rada je vrjednovati zemljište za izgradnju golf terena u Barbarigi. U tu svrhu primjenjene su metode bonitiranja zemljišta prema Pravilniku o sadržaju …(NN 106/98) i kriteriji pogodnosti zemljišta za podizanje golf igrališta (Palmer i Jarvis,1979). Terenska i laboratorijska istraživanja provedena su prema normativima za izradu detaljnih namjenskih karata. Na području istraživanja izdvojeno je 11 kartiranih jedinica koje predstavljaju različite zemljišne kombinacije crvenice različitih dubina, smeđeg tla na vapnencu, te kamenjara. Najpogodnije zone za izgradnju golf terena čine srednje duboke i duboke crvenice, blagih krških padina i niske stjenovitosti, te antropogenizirane crvenice krških poljica. Ostala tla su ograničena dubinom, stjenovitošću i kamenitošću.

Proceedings . 47th Croatian and 7th International Symposium on Agriculture . Opatija . Croatia (116–120), 2012

The aim of this study was to determinate the effect of soil slope (12% and 22%) on chemical soil ... more The aim of this study was to determinate the effect of soil slope (12% and 22%) on chemical soil properties of different parts of the slope (marl soils of vineyards in the Plešivica wine-growing region). In the surface and the subsurface soil layer on the upper third of the slope, the pH value is higher than on the lower third, with significant differences only on the steeper slope. The amount of total carbonate significantly increases from the lower part of the slope to the upper part, in both layers and in both locations, while the amount of physiologically active lime increases only on the steeper slope. On both locations, there is no statistically significant difference between physiologically active phosphorus and potassium supplies on different parts of the slope.

Geoadria, 2011

U radu autori analiziraju geološke, geomorfološke, pedološke, klimatske, hidrološke i fitocenološ... more U radu autori analiziraju geološke, geomorfološke, pedološke, klimatske, hidrološke i fitocenološke značajke otoka Korčule. Otok izgrađuju vapnenci i dolomiti kredne starosti, mjestimice prekriveni terra rossom i kvartarnim pijescima. Morfološki, reljef otoka Korčule obilježava izmjena uzvisina i polja, te vrlo razvedena obala. Na otoku Korčuli nalazi se velik broj pedosustavnih jedinica (kalkokambisol, crvenica, koluvij, ocrveničena crnica, te rigolana tla polja i terasa). Otok obilježava Csa tip klime (mediteranska klima s blagim zimama te suhim i vrućim ljetima). Na otoku ne postoje površinski vodeni tokovi, a samo je jedan stalni izvor pitke vode malog kapaciteta. U vegetacijskom, odnosno bioklimatskom pogledu otok Korčula pripada mediteranskoj vegetacijskoj regiji. Na otoku se razlikuju dvije vegetacijske zone: stenomediteranska i eumediteranska. U otočnim uvjetima prirodni resursi su ograničeni, stoga njihova eksploatacija treba biti u skladu s „održivim razvojem“. U tom smislu predložene su smjernice budućeg razvoja otoka Korčule.

Naše More, 2012

Due to the geographical position of the island of Vis, its climate features are under the strong ... more Due to the geographical position of the island of Vis, its climate features are under the strong impact of the sea. The data analysed for the period between 1981. and 2009. show positive rising trend of mean annual air temperature and mean annual precipitation, and they are inversely proportional to mean annual humidity. Changes in the values of air temperature and humidity (in the period analysed) are mainly in accordance with the data for the Mediterranean region (except from its eastern part). The changes of the values of mean annual precipitation are not in accordance with the data for the Mediterranean region where the amount of precipitation is mainly decreasing. In the period analysed, there is a great variability of air temperature and precipitation values which is more pronounced in summer precipitation, which emphasizes the negative impact of summer aridity in the years when the deviation from the average is negative.

Nase More

The basic assumption of this paper is that the relationship between geological basics, geomorphol... more The basic assumption of this paper is that the relationship between geological basics, geomorphological and pedological characteristics, with structural features of the natural and cultural landscape can serve as a criterion to determine landscape typology with respect to sensitivity to natural processes and anthropogenic influences. Karst natural and cultural landscape of Vis Island, continuously developed under the influence of traditional agriculture, transformed Vis Island into landscape of unique identity and relevance in the wider context of the Adriatic and the Mediterranean. Its characteristics are significant typological variations, authenticity and interdependence of natural and cultivated landscape structure, which makes significant difference respective to appearances of natural and human environment on other Adriatic islands. In this paper character and scope of the impact of natural and social features of the landscape were assessed and sensitivity of areas to existing...

Nase More, 2012

Na temelju općih morfoloških i morfostrukturnih osobina moguće je determinirati nekoliko osnovnih... more Na temelju općih morfoloških i morfostrukturnih osobina moguće je determinirati nekoliko osnovnih dijelova otoka Visa: sjeverni, središnji i južni hrbat, te sjevernu i južnu udolinu, koji su izduženi u smjeru Z (ZJZ) – I (ISI). Morfološki najizraženiji su južna udolina (veća i gospodarski značajnija), koju velikim dijelom izgrađuju krška polja, te hrbat koji dominira središnjim dijelom otoka. Karbonatna osnova otoka Visa preoblikovana je tektonikom, a porast morske razine od oko 120 m nakon posljednjeg ledenog doba dao je otoku današnje konture. Ispucale karbonatne stijene izložene djelovanju klimatskih, bioloških i antropogenih procesa bile su temelj za oblikovanje krškog reljefa. Egzogeni destrukcijski (krški, fluvio-krški, derazijski i abrazijski) i akumulacijski procesi oblikovali su konačan izgled otoka kakav ima i danas. Materijal ispiran s padina ili erodiran djelovanjem paleo tekućica, akumuliran je u morfološkim depresijama u unutrašnjosti otoka, dok je uz obalnu liniju isp...

Nase More, 2013

The object of this study are hillslopes of the Vis island. The slopes can be defined as relief su... more The object of this study are hillslopes of the Vis island. The slopes can be defined as relief surfaces determined by geographical position, slope inclination (related with horizontal surface) and slope aspect. Recent slope shapes can be defined as result of series of natural and anthropogenic factors during relief genesis and evolution. It is possible to correlate slope characteristics with geological structure and other natural geographic features (climate, soils, vegetation etc.) using geomorphometrical analysis. The main aims of this study are: a) analysis of morphometrical relief indicators (hypsometry, slope inclination and slope aspect), b) analysis of relationships between morphometrical indicators, and c) analysis of relatioships between morphometrical parameters, structural and lithological features, in order to gain more detailed understanding of exogeomorphological and morphostructural features of the investigated area. The final intention is to assess extent and intensi...

International Scientific Symposium "Man and Karst", Book of Abstracts., 2011

The morphology of surrounding hillslopes of karst poljes of Vis Island reflects past and present ... more The morphology of surrounding hillslopes of karst poljes of Vis Island reflects past and present tectonic, climatic and biologic processes that drive soil production, mobilization, and transport. Rock mass and soil transport results in modelling of hillslopes and positioning of inflexion points.
Today, Vis Island is characterized by the lack of water, so intense formation of hillslopes occurred during more humid period in the geologic past, when the rainfall amount was greater than the potential evapotranspiration.
To get more detailed insight into morphogenesis of the hillslopes, a number of profiles of the surrounding slopes of the poljes were analysed. The shape analysis was based on the digital elevation model. Convex slopes indicate younger uplifts and are dominated by destructive processes, while concave slopes are genetically older and are dominated by accumulation processes. In this area, younger uplifts occurred in Neogene-Quaternary Neotectonic tangential phase characterised by stress of N-S direction. This stress regime leads to a transformation of hillslope landscape, refolding of the existing structures and the formation of new ones. Reactivation of the existing discontinuity during neotectonic phase is a consequence of the fact that each new tectonic cycle, with the new regime of the main stress direction, uses existing discontinuities (that take a part of directed pressure).
If the hillslope profiles and tectonics are compared, it can be seen that the hillslope shapes and existing faults and fracture systems are in correlation and in an almost "ideal position" for the reactivation in neotectonic cycle.
Analysis of hillslope shapes and correlation with tectonics can be used to explain evolution stages, related processes and relative age differences between hillslopes, related karst poljes, and, consequently, the relief features of southern part of Vis Island. Also, it can be used to predict future stages of evolution, which is of great importance for numerous practical purposes.