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Earth and environmental sciences cover all planetary and Earth science aspects, including solid Earth processes, development of Earth, environmental issues, ecology, marine and freshwater systems, as well as the human interaction with these systems.
Earth and Environmental Sciences
Abstract
The fuzzy clustering technique is one of the ways of organizing data that presents special patterns using algorithms and based on the similarity level of data. In this study, in order to cluster the resulting data from the Babakoohi Anticline joints, located north of Shiraz, K-means and genetic algorithms are applied. The K-means algorithm is one of the clustering algorithms easily implemented and of fast performance; however, sometimes this algorithm is located in the local optimal trap and cannot respond with an optimal answer, due to the sensitivity of this algorithm to the centers of the primary cluster. In addition, it has some basic disadvantages, such as its inappropriateness for complicated forms and also the dependency of the final result upon the primary cluster. Therefore, in order to perform the study more accurately and to obtain more reliable results, the genetic algorithm is used for categorizing the data of joints of the studied area. Applying this algorithm for leaving the local optimal points is an effective way. The results of clustering of the aforementioned data using the two above techniques represent two clusters in the Babakoohi Anticline. Furthermore, for validity and surveying of the results of the suggested techniques, various mathematical and statistical techniques, including ICC, Vw, VMPC, and VPMBF, are applied, which supports the similarity of the obtained results and the data clustering process in two algorithms.
Abstract
In June 2017 a new sauropod trackway locality was discovered in the central part of the Adriatic–Dinaric Carbonate Platform (ADCP), on the island of Hvar (Croatia). The track site is situated on the northern shore of the western edge (Pelegrin) of the island in the upper Turonian – lower Coniacian limestone series. The track site contains altogether 13 footprints arranged in four possible trackways. The largest footprints have a diameter up to 80 cm. In some places the limestone surface is strongly karstified and the tracks are partly eroded, which has certainly modified the original shape and size of the footprints. Microfossil assemblage from the track-bearing beds suggest an early Coniacian age for the tracks. The new trackways on Hvar Island further strengthen the earlier hypothesis that sauropods were present in the western Tethyan archipelago during the late Cenomanian–late Campanian period. In addition, the new tracks, together with those from the Žukova Cove of Hvar, represent two, possibly slightly different stratigraphic horizons close to the Turonian–Coniacian boundary, and suggest that the occurrence of sauropods on the ADCP and possibly also on other parts of the Apulian microplate was not accidental, but rather periodical and more frequent than previously thought.
Abstract
With the introduction of the Water Framework Directive, the relative importance of smaller waterways increased. This statement is particularly true for Hungary, where water-quality monitoring of most smaller rivers only began 12 years ago. Due to their large number, and the lack of historical data concerning their state, systematic monitoring is a challenge.
In the current study, 101 creeks are characterized on the one hand by 13 physico-chemical quality parameters (pH, electric conductivity, chloride ion concentration, dissolved oxygen, oxygen saturation, biochemical oxygen demand, chemical oxygen demand, total organic carbon, ammonium nitrogen, total inorganic nitrogen, total nitrogen, orthophosphate and total phosphorus), on the other hand by their watershed's relief, land use, and point sources' pollution indicators. Euclidean distance between water bodies (henceforth WBs) is calculated according to normalized physico-chemical monitoring values. They are grouped into clusters using the hierarchical clustering method. Watershed characteristics are used to explain the clustering via linear discriminant analysis.
The investigation revealed that the main driver of cluster group creation is related to human impact: diffuse agricultural and point-source pollution. The first of the three clusters involved water bodies with low or no human impact; the second cluster contained those with medium-level anthropogenic disturbance, while waters with high pollution values formed the third cluster. Mean distance between heavily polluted waters was 1.5 times higher than that between those showing no or low disturbance, meaning that pristine waters are more similar to one another than polluted ones. The current number of samples per river is twice as high in cluster 1 as in cluster 3, revealing that there is room for optimization of the monitoring system. This contribution uses Hungary as a case study.
Összefoglalás
A klímaváltozásnak köszönhetően a következő évtizedekben a talajok defláció veszélyezettségének mértéke emelkedni fog hazánkban (CSORBA et al. 2012). A kutatásunk során arra kerestünk választ, hogy a talajtani alaptulajdonságok miként befolyásolják a kritikus indítósebességet és jelenleg mennyire defláció veszélyeztetettek a Dél-Alföld talajai.
Mintaterületként a Szeged környéki talajokat választottuk. A vizsgálataink során megállapítottuk, hogy az összes vizsgált talajparaméter közül az agronómiai szerkezet, azon belül is a rögfrakció az, ami leginkább befolyásolja a kritikus indítósebességet. Ez felhívja a figyelmet az ember szerepére, aki megfelelő agrotechnikával képes lenne a széleróziós kockázat csökkentésére (BODOLAY 1966; SHAHABINEJAD et al. 2019). A szélcsatornás kritikus indítósebesség vizsgálatok eredményeit összevetettük az időjárási adatokkal, és ezek eredményeit kivetítettük Csongrád megye területére. Kutatásunk során meghatároztuk a széleróziós események jellemző éves előfordulását (homok: 16,8 esemény; homokos vályog és vályog 1,6 esemény; agyagos vályog: 0,4 esemény), ezen események átlagos hosszát (homok: 3,0 óra; homokos vályog és vályog 1,4 óra; agyagos vályog: 1,0 óra) és a deflációnak kitett területetek aránya Csongrád-megyében (homok: 8,4%; homokos vályog és vályog 29,1%; agyagos vályog: 20,0%).
Kutatásunkkal képet kaptunk arról, hogy a defláció mekkora területet érint és mennyire jelentős talajvédelmi probléma Csongrád megyében. Korábbi kutatásaink bizonyítják, hogy egy párperces széleróziós esemény is súlyos veszteséget okozhat a talajok tápanyagtartalmából (FARSANG et al. 2011; FARSANG 2016), mely csupán csak egy aspektusa a szélerózió negatív hatásainak.
Summary
Adaptation is the most important strategy to reduce the effect of climate change and soil erosion. During this process adequate, rational land use is necessary to ensure climate resilience. Therefore, the main objective in this study was to evaluate the susceptibility of different land use intensities (arable land and grassland) to soil erosion. The rainfall simulation method is a good tool to measure and estimate soil erosion in situ. The comparative measurements were carried out in the field with a Shower Power-02 simulator on 6 m2 plots in Gerézdpuszta, where the slope angles were ~8% and the simulated rainfall events had high intensities (~70-96 mm h−1). The runoff and soil loss were significantly higher from arable land. The runoff-infiltration ratio and runoff coefficient showed lower infiltration capacity in the case of arable land. On average, the suspended sediment loads were tenfold higher under intensive land use. In the case of grassland a moderate increase in infiltration was observed due to higher rainfall intensity, as also reported in the literature. The rainfall simulation method provides good data for soil loss estimations.
Összefoglalva
A hazai talajosztályozás diagnosztikus szemléletű megújítását minden erőmmel és képességemmel támogatom, ám a Vitaanyagban ismertetett módon történő leváltását jó szívvel nem tudom javasolni. Javaslom ugyanakkor az egyes részletkérdések (akár munkacsoportokban történő) megvitatását, a terepi és laboratóriumi módszertan fejlesztését, a módszerek konvertálhatóságának megteremtését, illetve a Vitaanyag módszertanának – mint 1. verziójú javaslatnak – a meglévő módszertannal párhuzamosan történő tesztelését szelvényfeltárások és a talajtérképezési munka során.
