The Bokanjačko blato karst polje (field) is a typical depression along the eastern Adriatic coast that is filled with lake sediments. This large-scale structure is also an hydrologically important ...region as wells in southern part of the karst polje comprise the water supply for surrounding towns and villages. The evolution of this polje, however, remains poorly understood. A 7.8 m long sediment core from the south-eastern part of the karst polje is utilized in this study to enable a multiproxy approach to the reconstruction of depositional processes that have occurred over the last 10.3 ka cal BP. The sedimentological, mineralogical and geochemical characteristics, as well as palynological analyses of this core indicate that the whole sediment sequence consists of lake sediments alongside a variable amount of carbonates and silicates. The lake existed for approximately 10,300 years before it was drained for agricultural purposes in the 1960s. Depositional changes are also evident throughout the core; between 10.3 and 4.2 ka cal BP, a higher values of magnetic susceptibility (MS) and concentrations of lithogenic elements indicate increased erosion and input of material from the catchment and therefore wetter climatic condition. Deposition of siliciclastic detrital material gradually decreased from 4.2 ka cal BP onwards, replaced by carbonate sedimentation alongside minimal input of the former. The carbonate-based sandy silt sedimentation remains until hydromelioration of the depression. The results of this study show that the lake level gradually increased between 4.2 and 2.9 ka cal BP, evidenced by a higher carbonate content and a lower proportion of detrital material, reaching a maximum between 2.9 and 1.6 ka cal BP. Data also show that at 1.6 ka cal BP, the lake level was likely lowered due to higher nutrient content, including sulfur (S) and phosphorus (P), as well as organic compound levels, prior to human intervention and hydromelioration for agriculture. High concentrations of the nutrient elements, lead (Pb), copper (Cu), and zinc (Zn) in the upper 40 cm of this sequence are indicative of the influence of agricultural activities across the karst polje as well as anthropogenic atmospheric pollution. Geochemical and sedimentological proxies illustrate centennial-scale variability in carbonate deposition and erosional runoff processes comparable with the natural climatic and anthropogenic factors that are known to influence the evolution of Holocene karst poljes across the central Mediterranean.
This study presents a newly discovered site of Lychnothamnus barbatus, one of the rarest charophytes worldwide of a disjunctive, Euro-Australasian-American distribution. The species is the only ...representative of the genus Lychnothamnus on a global scale, hence its threat poses a risk of extinction to the entire lineage. In June 2019, Lychnothamnus barbatus was discovered in Lake Malo Blato, a north-western bay of Lake Shkodra/Skadar, to be a new element to the flora of Montenegro. Lychnothamnus barbatus was recorded at a depth of 3 m, in nutrient-poor but calcium-rich water and on a muddy substrate in the zone of submerged vegetation composed of charophytes and angiosperms. The collected thalli of L. barbatus were young and sterile, green, slightly calcified, and up to 15 cm high. Except for gametangia, all features which are diagnostic for this rare charophyte were well developed. Based on the synthesis of the current state of knowledge, the new site of L. barbatus is presented in the context of the species’ ecological requirements and climatic plasticity, current distribution, and history in the Balkans.
•A new site of a worldwide rare charophyte was discovered in the Balkans.•Lychnothamnus barbatus is a new species to the flora of Montenegro.•The species occurs in nutrient-poor but calcium-rich water and on a 3 m deep muddy substrate.•The history of Lychnothamnus in the Balkans dates back to the Miocene.
•Selected extreme rainfall events in the last 25years in Slovenia were investigated.•Rainfall characteristics triggering flash floods and landslides are different.•Copulas yield useful ...intensity–duration–frequency relationship (IDF).•Rainfall inter-event time selection has significant influences on IDFs.•Different rainfall thresholds should apply in different parts of Slovenia.
Floods, landslides and debris flows are natural events that occur all over the world and are often induced by extreme rainfall conditions. Several extreme events occurred in Slovenia (Europe) in the last 25years that caused 18 casualties and approximately 500million Euros of economic loss. The intensity–duration–frequency (IDF) relationship was constructed using the Frank copula function for several rainfall stations using high-resolution rainfall data with an average subsample length of 34years. The empirical rainfall threshold curves were also evaluated for selected extreme events. Post-event analyses showed that rainfall characteristics triggering flash floods and landslides are different. The sensitivity analysis results indicate that the inter-event time definition (IETD) and subsample definition methodology can have a significant influence on the position of rainfall events in the intensity–duration space, the constructed IDF curves and on the relationship between the empirical rainfall threshold curves and the IDF curves constructed using the copula approach. Furthermore, a combination of several empirical rainfall thresholds with an appropriate high-density rainfall measurement network can be used as part of the early warning system of the initiation of landslides and debris flows. However, different rainfall threshold curves should be used for lowland and mountainous areas in Slovenia.
V članku so predstavljena bronastodobna najdišča in tista na prehodu v starejšo železno dobo s prostora Zgornje Dravinjske in Savinjske doline ter Kozjanskega. V Zgornji Dravinjski dolini sta ...imeli v bronasti in starejši železni dobi dominantni vlogi naselbini Brinjeva gora in Ljubična nad Zbelovsko goro. Večji poudarek je namenjen Zgornji Dravinjski dolini in poznobronastodobni naselbini na Blatu pri Slovenskih Konjicah. To je bil kratkotrajen zaselek z manjšimi stavbami, s prevladujočim živinorejsko–poljedelskim gospodarstvom in z večjo ter od naselbine Blato odmaknjeno vodno jamo, ki jo interpretiramo kot kraj nepovratnega odlaganja predvsem keramičnih posod iz horizonta mlajše kulture žarnih grobišč. V jami so bili tudi večji prodniki, živalske kosti, drobci oglja in lesa, na dnu jame pa je ležalo potopljeno razmeroma dobro ohranjeno hrastovo deblo.
Spatial planning is a vital process for a rapid and successful development of projects related to wetland management, and thereby projects related to tourism. Tourist activities could provide a boost ...to the development of general understanding of wetlands and raise public awareness of the functions and the ecosystem services wetlands provide. The tourism economy could be a source of income and could provide employment opportunities in rural areas. However, tourists also have an impact on wetlands. Protected areas accessible to tourists require a comprehensive management. In order to ensure a harmonious relationship between tourism activities and environmental protection, when developing an urban design within a protected area, it is crucial to have a sensitive approach. The paper suggests an approach to the development of the Urban Design "Karaotok", within the Hutovo Blato Nature Park.
Geoekološko vrednovanje reljefa Parka prirode Hutovo blato s aspekta njegove turističke i rekreacijske valorizacije provedeno je na temelju prethodne geomorfološke analize. U radu je promatran ...turizam i rekreacija kao sociološki elementi razvoja parka prirode Hutovo blato. Za postupak geoekološkog vrednovanja izdvojeni su reljefni oblici određenog stupnja atraktivnosti (vrhovi, padine, korita i dolinska dna, vododerine, područje oko Deranskog jezera, područje oko Svitavskog jezera i Svitavsko jezero), koji su vrednovani za sljedeće oblike rekreacije: šetnja, brdski biciklizam, rekreacijski biciklizam, promatranje ptica i krajolika te kajaking i kanuing. Stupanj pogodnosti reljefa za navedene vidove rekreacije određen je na temelju fizičke pogodnosti, estetske vrijednosti i dostupnosti. U postupku vrednovanja primijenjena je metoda relativnog vrednovanja reljefa. Provedeno vrednovanje ukazalo je na vrijedne i potencijalno vrijedne dijelove reljefa, ali i na one ograničavajuće elemente krajolika, zbog kojih pojedini dijelovi nisu do sada dovoljno turistički valorizirani. To se posebno odnosi na istočni i jugoistočni dio Parka s izraženim problemom fizičke pogodnosti i (ne)dostupnosti (udaljenost te nepostojanje ili neuređenost pješačkih staza, otežane plovnosti, nepristupačnosti obale obrasle vegetacijom). Predložene su moguće aktivnosti za povećanje geoekološke vrijednosti prostora (uređivanje infrastrukture za rekreacijski biciklizam, te obnova starih i uređenje novih edukativnih staza za šetnju i edukaciju na prostoru koji ima potencijal postati zanimljiv i atraktivan dio Parka prirode Hutovo blato).
•Hg, Pb, Cd and As were determined in common carp and European catfish from Buško Blato lake.•In most cases heavy metal concentration is higher in catfish compared to carp.•In muscles of carp and ...catfish multiple correlations between different heavy metals are found.•Positive correlation of heavy metals with age and body mass exists in tissues of carp and catfish.•Older and bigger carp and catfish are not recommended for human nutrition.
The purpose of this study was to quantify the bioaccumulation of Pb, Hg, Cd, and As in tissues of carp (Cyprinus carpio) and catfish (Silurus glanis) from Buško Blato in Bosnia and Herzegovina. Arsenic concentrations were below the Maximal Admissible Concentration (MAC) for Croatia and other countries. Mercury concentrations were below 1mgkg−1, but in most muscle samples of both species and all catfish liver samples, the values were higher than 0.5mgkg−1 (higher than the MAC for many countries including Croatia). Lead concentrations were higher than 1mgkg−1 (the MAC for Croatia) in most muscle samples; all kidney and most catfish liver samples also exceeded 1mgkg−1. Cadmium concentrations in all tissues, other than the gonads, were higher than 0.1mgkg−1 (MAC for Croatia), with the highest concentrations found in the kidneys. The only gender difference was found in carp, where a 68.4% higher concentration of As was found in the fry compared to the milt (P<0.05). Concentrations of all of the elements were higher in catfish compared to carp for most tissues. Significant correlations were found between all of the elements in the muscles and the liver of carp. In catfish, the muscles were the only tissue in which multiple correlations were found. Linear positive correlations with age and body mass were demonstrated for the concentrations of all heavy metals for all tissues except the gonads in both fish species. We concluded that significant heavy metal accumulation in carp and a catfish tissues correlates with age and body mass; bioaccumulation is species- and tissue-specific and is different for each element.
U radu se obrađuju toponimi Općine Blato na otoku Korčuli. Imena su prikupljena terenskim istraživanjem i naglašena prema izgovoru ispitanika. Korpus je prezentiran uz semantičku i etimološku analizu ...koja je ukazala i na tragove romanstva u različitim jezičnim slojevima. Radu je priložen popis apelativa iz lokalnoga govora koji su motivirali toponime.
Temeljem podataka matičnih knjiga za Blato i Pupnat, u članku se analizira institut kumstva u ruralnom dijelu otoka Korčule u drugoj polovici 19. stoljeća, koji je bio važan mehanizam za stvaranje ...društvenih mreža. Fokus ovog istraživanja je na analizi broja i spolne strukture krsnih kumova, intervalu rođenja i krštenja djeteta, podudarnosti imena i prezimena djece i njihovih kumova, te višekratnih kumstava. Kod vjenčanih kumova također su se razmatrali broj i spolna struktura kumova, podudarnost prezimena i višekratna kumstva.
Treatment of the sludge from water-purification plants is becoming more and more urgent due to the inability to increase its storage area. To avoid CO2 emissions, the use of non-Portland cement ...binders is recommended. The application of geopolymerization of waste sludge (WS) from water-purification plants is a novel solution. Curing conditions including high temperature, pressure or microwaves enhance the formation of geopolymer bonds. This paper presents the results of a research on the treatment of the WS of the Thu Duc water-purification plant (Vietnam) with the geopolymerization method. Solid phases were prepared by mixing the WS and fly ash (FA). The FA proportions of the solid phases were (10, 40, 70) w/%. The alkali-activated solution (AAS) was a mixture of a 40 w/% NaOH 6M solution and 60 w/% water glass (WG: Na2O.nSiO2 with n = 1.75 and volumetric density r = 1.40 kg/L). The geopolymer materials were mixtures containing an 80 w/% solid phase and a 20 w/% liquid phase of the AAS. Geopolymer samples were formed in a cylindrical steel mold with a diameter of 10 mm at a high pressure. The samples were cured in a 112 W microwave oven for 30 s or in a dryer at 110 °C for 24 h. The compressive strength and volumetric density of both sample groups were determined and compared to each other. The formation of geopolymer bonds was investigated using XRD, FTIR and SEM.
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