Maluku is one of the provinces in Eastern Indonesia which has a variety of cultures. Various Maluku cultures contain mathematical values that we can use as a learning approach. Maluku culture, such ...as the shape of traditional houses, maritime activities of the Maluku people, and traditional Maluku dances contain mathematical values that we can explore in learning mathematics. This culturally integrated mathematics learning will help students understand concepts because the material studied is related to students' lives. This research used Research and Development method that aims to develop a mathematics learning video based on Maluku culture, namely the Saureke-Reka dance using Powtoon. This research used ADDIE (Analyze, Design, Development, Implementation, and Evaluation) model. The learning videos discusses the learning of Mathematics contained in the "Saureka-Reka" dance. The reason for choosing the object of dance study is because the "Saureka-Reka" dance is a dance that is popular among young people in Maluku, from elementary school to university level. This dance is also often used as an everyday game. This media is made with the integration of culture, mathematics, and of course technology. Data collection techniques in this study was a questionnaire. The data collection instruments used were material expert and media expert validation instruments, and questionnaire sheets. Data were analyzed using descriptive quantitative techniques. This study uses the ADDIE model (Analyze, Design, Develop, Implementation, Evaluation). The results of the study show that the learning videos developed are declared very feasible. It can be seen from the value of the validity test by material experts is 84% and the value of the validity test by media experts is 86%. The practicality test results by users reach a value of 90% which indicates that this media is very practical. Media users responded positively to this media. Some positive responses include that this media is interesting and helps them understand the material. Thus, researchers highly recommend this media for use in mathematics learning. This media is passive or one-way only. The author recommends that future researchers can develop more interactive media.
The aim of the paper is to analyse the changes in erosion intensity in Jablanica region between 1971 and 2018, using the Gavrilović method. Study area covers the catchment of three left tributaries ...of South Morava river, which have vary unstable river regimes. Natural conditions have a negative impact on intensity of the erosion process with unfavourable geological and pedological structure, precipitation regime, high slope values and significant vertical dissection of the terrain. Changes in erosion process are caused by changes in agricultural production as well as anti-erosion works, that have been carried out during the second half of the 20th century.
The oceanic anoxic event in the Early Toarcian, often referred to as the ‘Torcian Oceanic Anoxic Event’, led to widespread deposition of organic-rich black shales and geochemical anomalies in ...elemental distribution and multiple isotope systems in the Early Jurassic ocean. Best characterized by its hallmark carbon isotope anomaly, the event is widely regarded as a prime example of rapid greenhouse warming-related changes in the Mesozoic Earth system. However, despite numerous studies, details of its forcing mechanisms, exact duration and the role of regional effects remain debated. This article presents new data (high-resolution organic carbon isotope, calcareous nannofossil and elemental geochemical analyses) from the black shale-bearing Lower Toarcian section in the Reka Valley, Hungary, with the aim of assessing any regional differences in the sedimentary and geochemical record and their bearing on the underlying oceanographic and climatic processes. Following a short segment with a positive trend at the base of the section, values of the carbon isotope data here are turning to a negative trend with a steep, stepwise drop in two negative shifts, reaching their minimum before a positive trend with oscillations characterizing the top part of the section examined. The shape of the curve and nannoplankton biostratigraphy (recognition of zones NJ5b, NJ6 and NJ7) allow reliable correlation of these data with the global carbon isotope perturbation recorded elsewhere in the Early Toarcian. It is proposed here that it would be fitting to rename the Torcian Oceanic Anoxic Event as the ‘Jenkyns Event’, to honour the seminal contributions of Hugh Jenkyns. The cyclostratigraphic analysis in this study suggests that the duration of the negative isotope excursion at Reka Valley is 200 kyr, 350 kyr or 1 Myr, depending on which astronomical forcing parameter controls the most prominent cyclicity. Spectroscopic analyses suggest that the source of the organic matter, marine algae according to previous studies, did not change considerably during the main negative carbon isotope excursion. The variability observed in major element concentrations and enrichments relative to the average shale in the Reka Valley black shales can be regarded as mixtures of terrigenous aluminosilicates and calcium carbonate as two endmembers. Consequently, the terrigenous compositional endmember of the studied black shales consists of a mixture of an illitic/smectitic and a kaolinitic clay, which supports previous suggestions of increased weathering under extremely humid climate in the hinterland during the Jenkyns Event.
Spomladi 2015 so predstavniki Alumni kluba geografov Univerze v Ljubljani, Komisije za hidrogeografi jo Zveze geografov Slovenije in Občine Miren predstavili »Strokovne zasnove ureditve vodnega in ...obvodnega prostora ob reki Vipavi na območju občine Miren-Kostanjevica«. Dokument, ki je nastal na podlagi dveh delavnic z domačini ter terenskega druženja geografov, išče nove razvojne priložnosti ob vse bolj čisti Vipavi in nove možnosti za čezmejno sodelovanje.
Cultural diversity and biodiversity are strongly intertwined through the ways in which local human communities have understood, categorized, perceived, and used nature and species for centuries. Folk ...nomenclature and uses of wild plants in particular are strongly linked to specific ethno-diversities and have often been considered as cultural markers. In the current study, through thirty-one interviews with elderly villagers, the ethnobotany of five Albanian villages in North Macedonia was recorded, as these villages are inhabited by descendants of Reka Albanians, whose peculiar dialect and customs have been the subject in the past of some linguistic, historical, and ethnographic works. A few folk names and utilizations of commonly used species (such as Rumex, Urtica, Tilia, Crocus, and Hypericum spp.), as well as the traditional customs of collecting tree cambium during the spring and ritually adorning home doors with Cornus mas and Salix spp. branches on St. George’s Day, partially overlap Macedonian/Bulgarian folklore, and, to a minor extent, data previously collected in NE Albania and South Kosovo. Nevertheless, some archaic uses (such as the consumption of Crocus corms) remain very idiosyncratic. While the origin of the Reka Albanians and the exact historical reasons for their peculiar ethnobotany practices cannot be exactly established, the data showed that this cultural group living at the cultural edge between the Albanian and South Balkan Slavic realms has maintained its diversity until the present. Its uniqueness should be valorized and celebrated.
The Vardar Zone is a product of the Triassic-Jurassic opening of the Neotethys, Jurassic obduction, Late Cretaceous/Paleogene consumption of the oceanic crust and continental collision. During the ...last process, the Eastern Vardar Zone was thrust over the Central and eventually both onto the Western Vardar Zone. The present paleomagnetic and structural study provided new results from the first two zones in the Belgrade area. The younger set of data, together with published ones from the third zone, provide firm evidence for about 30° clockwise vertical axial rotation of the Vardar Zone between 23 and 18 Ma, connected to extension driven by the roll-back of the Carpathians lithosphere.
Earlier, the Vardar Zone was affected by intensive compression generating a nappe pile, comprising the Eastern, Central and Western Vardar Zones. This assembly was eventually thrusted over CCW rotating Adriatic elements in the Paleogene. The rotation triggered a system of right lateral strike slip faults between different tectonic slices in the Vardar Zone. This tectonic model offers a plausible explanation for the paleomagnetic directions of post-folding age of the Upper Cretaceous flysch of the Central Vardar Zone. Nevertheless, the possibility of remagnetization of the magnetite bearing flysch during Late Neogene uplift can not be excluded.
•The Western-Central-Eastern Vardar Zones rotated ≈ 30° CW between 23 and 18 Ma•It was connected to extension due to the roll-back of the Carpathian lithosphere•Earlier compression generated thusting and strike slip faults•The pile of thrusted segments of the Zone were emplaced onto CCW rotating Adria•Relevant paleomagnetic results may be interpreted in the light of the above processes
The Cu-Au deposit of Bor (Serbia) represents a continuum of mineralization styles, from porphyry-style ore occurring in quartz-magnetite-chalcopyrite veins and chalcopyrite disseminations to ...high-sulfidation epithermal Cu-Au ores in pyrite-chalcopyrite and anhydrite-sulfide veins. Decisive for the great economic importance of Bor is the presence of exceptionally rich high-sulfidation massive sulfide orebodies, composed of pyrite + covellite + chalcocite/digenite and minor anhydrite and enargite. They form irregular bodies measuring 0.5–10 million tons of ore grading up to 7% Cu, hosted by andesites and surrounded by intense argillic alteration. This study focuses on a small but rich underground orebody mined out recently, where limited drillcore is preserved for quantitative geochemical study. This paper documents the vein relationships within the deep porphyry-style orebody of Borska Reka, the transitional porphyry-epithermal veins, and the overlying and laterally surrounding epithermal massive sulfides of the Bor deposit. Geological observations indicate that the formation of massive sulfide orebodies concludes the ore formation. Mass balance calculations, recast into geologically realistic bulk fluid-rock reactions, confirm textural evidence that near-isovolumetric replacement of andesite host rocks is the dominant formation mechanism of massive sulfide orebodies at Bor, whereby all lithophile elements including Si are dissolved and only Ti stays relatively immobile. While net volume changes for individual mineralization styles within the massive sulfide orebody vary from − 16% volume loss to + 127% volume gain, overall volume change for the whole massive sulfide orebody was probably slightly negative. Brecciation is important only as means of creating channelways for reactive fluid that turns the andesite protolith into massive sulfide, whereas net breccia infill occurred only locally.
Kratovska Reka is a short (17.3 km) left tributary of Kriva Reka, whose watershed (68.5 km2) is located on the northwestern slopes of the Osogovo Mountains (North Macedonia). Due to the favorable ...natural conditions and anthropogenic factors, the Kratovska Reka catchment is under a high risk of natural hazards, especially water erosion and landslide occurrences. For this reason, the paper presents an approach of modelling of potential erosion and areas susceptible to the above-mentioned hydro-meteorological hazards in the Kratovska River catchment. Firstly, this study analyzed the main geographical features that contribute to intensive erosion processes in the area. Then, using the Gavrilović EPM erosion potential method, an average value of 0.56 was obtained for the erosion coefficient Z, indicating areas prone to high erosion risk. Furthermore, by using landslide susceptibility analysis (LSA), terrains susceptible to landslides were identified. The results shows that 1/3 of the catchment is very susceptible to mass movements in wet conditions (landslides). According to the combined multi-hazard model, 3.13% of the total area of the Kratovska River catchment is both at high risk of landslides and under severe erosion. The Kratovska River catchment is significantly endangered by the excessive water erosion processes (39.86%), especially on the steep valley sides, i.e., terrains that are completely exposed, under sparse vegetation, and open to the effects of distribution/concentration of the rainfall amounts throughout the year. Identifying locations with the highest erosion risk serves as the initial step in defining and implementing appropriate mitigation measures across local and regional scales, thus enhancing overall resilience to environmental challenges.
Major palaeoenvironmental and palaeoceanographical changes occurred during the Early Jurassic Toarcian Oceanic Anoxic Event (T-OAE), due to a perturbation of the global carbon cycle and a crisis in ...marine ecosystems. The sequence of environmental change and regional differences during the T-OAE are not yet fully understood and organic-walled phytoplankton and other palynomorphs are well-suited, but under-utilised, in research into this event. Based on quantitative palynological analyses from a black shale-bearing succession at Réka Valley in the Mecsek Mountains of southwest Hungary, five sequential palynomorph assemblages are distinguished. These reveal major shifts in organic-walled phytoplankton communities, driven by palaeoenvironmental changes. In addition, palynofacies analysis helped to document changes in the composition of sedimentary organic matter, and to quantify the terrestrial input. Assemblage 1 is characterised by a moderately diverse phytoplankton community and high levels of terrestrial palynomorphs. Assemblage 2 records a significant peak of the euryhaline dinoflagellate cyst Nannoceratopsis. Assemblage 3 is distinguished by dominance of highly opportunistic prasinophytes and the temporary disappearance of all dinoflagellate cyst taxa. Assemblages 4 and 5 represent distinctive phases of a prolonged recovery phase with low diversity phytoplankton assemblages and intermittently high levels of terrestrially-derived palynomorphs. The successive disappearance of phytoplankton taxa and the gradual takeover by opportunistic euryhaline species at the onset of the T-OAE were related to several phenomena. These include reduced salinity in the surface waters, establishment of a stable pycnocline and deterioration of nutrient recycling, followed by oxygen deficiency throughout much of the water column. The high amount of terrestrially-derived palynodebris indicates intense runoff and freshwater input, driven by the early Toarcian warming and the enhanced hydrological cycle. Comparison with coeval European successions proves that the palaeoenvironmental changes during the T-OAE were not entirely synchronous, and local factors played a crucial role in influencing phytoplankton communities. In the Mecsek Basin, regional freshening of the surface waters and increased terrestrial input due to the proximity of the hinterland had a greater influence on phytoplankton communities compared to the open oceanic setting of the Tethys to the south.
•Detailed quantitative palynological analysis of a Toarcian black shale succession.•Five successive intervals recorded changes in organic-walled phytoplankton assemblages.•Peak of the euryhaline dinoflagellate Nannoceratopsis, followed by a blackout event.•Changes driven by global warming, enhanced runoff and freshening of surface waters.