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Abstract

Snowbed vegetation is one of the most sensitive alpine vegetation type to the climate change, because shortened period of snow cover has essential impact on the snowbed environment. We focus on its changes in the Western Tatras, which is a part of the Western Carpathians (Slovakia). The assessment of changes in snowbed vegetation is based on the method of pair comparison. In 2016–2018, we resampled 21 historical phytocoenological relevés of Festucion picturatae and Salicion herbaceae alliances from 1974 and 1976. Historical data include 45 species, while recent data include 50 species. We observed a decrease in the frequency of species characteristic for snowbeds and, on the other hand, an increase in that for strong competitors, especially grasses and small shrubs from adjacent habitats. According to Ellenberg’s ecological indices, there is some increase in temperature and decrease in light ecological factors in snowbed habitats. In S. herbaceae data, a statistically significant increase in the average species number was observed with new species that penetrated from the adjacent habitats. Changes in species composition between historical and recent data are confirmed by Non-metric multidimensional scaling (nMDS) ordination diagram. Linear mixed-effect models showed big variability in factors that have impact on phytodiversity; nevertheless, temperature is the most significant factor.

Abstract

The essential oil of the aerial parts of Thymus ciliatus (Desf.) belonging to the Lamiaceae family, was obtained by steam distillation and analyzed by GC-FID and GC-MS. 75 components were identified corresponding to 95.57% of the total oil. The major constituents of the oil were: elemol (6.80%), carvacrol (5.86%), γ-muurolene (5.18%), β-sesquiphellandrene (5.09%), bicyclogermacrene (5.04%), β-pinene (4.49%) and curcumene (4.20%), together with other compounds at relatively low levels: 1,8-cineol (3.66%), β-eudesmol (2.92%), β-bisabolene (2.81%), β-silinene (2.75%), camphor (2.64%), germacrone (2.34%), α-zingiberene (2.12%), δ-cadinene (2.08%), caryophyllene oxide (1.90%), spathulenol (1.88%), □-caryophyllene (1.88%), ar-turmerone (1.79%), α-pinene (1.52%), limonene (1.52%), selina-4,11-diene (1.46%), curzerenone (1.41%), germacrone B (1.37%), bornyl acetate (1.31%), β-farnesene (1.28%), borneol (1.23%), myrtenal (1.16%), zingiberenol (1.15%) and sabinene (1.13%). These results differ from those of previous studies reported on this species collected from other regions of Algeria and Morocco.

Abstract

The present work focuses on an ethnobotanical study of medicinal plants in the Belezma National Park (BNP), which is located in Batna city. It was conducted to precise on the medicinal plants in the park and gathers all the information on the therapeutic practice used by the local inhabitants of the study area. Using 300 questionnaire cards, ethnobotanical surveys of BNP were conducted during two campaigns (2017 and 2018). The obtained results allowed us to identify 50 medicinal plants used by the population of the region, which are divided into 27 families and 46genus.

The obtained results show both leaves and stems are mostly used for diseases’ treatment in the form of a decoction with a rate of 42.34%. For the treated diseases, the digestive disorders occupy the first place with a rate of 34.01%, followed by uro-genital diseases with a rate of 17.56%, 11.20% for respiratory diseases, 11.84% for orthopedic diseases and 6.23% for cardiovascular.

The founded results could be a database for research on phytochemistry and pharmacology for the national medicinal flora and the population of the BNP region. Also, they constitute a very valuable source of information.

Abstract

This paper examines the temporal dynamics of terrestrial mollusks of the Nikopol manganese ore basin technosols. The research was carried out at the Research Centre of the Dnipro Agrarian and Economic University in Pokrov (Ukraine). Sampling was carried out in 2012–2014 on four variants of artificial soil: formed on red-brown clays, on loess-like loams, on gray-green clays, and on humus-rich layer. The distribution of the number of individuals in a mollusk population was described by broken stick, Motomura, log-normal, Zipf, and Zipf-Mandelbrot models. It was shown that the series of models that best describe mollusk abundance distribution is specific for a particular species and technosols type and generally is invariant over time.

Abstract

The natural site of El-Mergueb, is one of the specific steppe ecosystem, that occupies an area of 16,481 ha; it is among the particular ecosystems in Algeria and is unique in northern Africa. It is located in the geographical limit of the Tell Atlas and the Saharan Atlas. It is at an altitude of 550 to 800 m, with a typically arid climate. The faunistic and floristic richness, quite specifically, contains species protected and classified in the IUCN: Chlamydotis and Gazella, as well as an autochthonous plant diversity: Stipa, Pistacia and Ziziphus. This study is based on the analysis of the vegetation by characterizing the associated soil type through the monitoring of the Eco-pedological relation during two seasons in three years: 2015−2016−2017. Nine soil profiles with a collection of twenty-one samples for each station of experimentation were collected. The results thus obtained showed that the content of the parameters analyzed is between low and average of the three stations. The average of the floristic analysis of the study area made it possible to define 34 botanical families spread over 69 botanical genus and 275 species. The analysis and the description of a natural space is important to establish a typology which is that is the basis for the development of management plans to conserve this category of protected areas. The FAC (Factorial Analysis of Correspondence) is relative to the individualization and the typology for three sequences, which corresponds to the groups (A), (B) and (C) also for the places in arid climate variants with very cold winters.

Abstract

The objective of the present study was the optimization of the parameters affecting the hydrodistillation of Ruta chalepensis L. essential oil using response surface design type Box-Behnken. After an appropriate choice of three parameters, 15 experiments were performed leading to a mathematical second-degree model relating the response function (yield of essential oil) to parameters and allowing a good control of the extraction process. The realization of the experiments and data analysis was carried out by response surface methodology (RSM). A deduced second-order polynomial expression was used to determine the optimal conditions necessary to obtain a better essential oil yield. These optimized operating conditions were: a granulometry of 2 mm, a condensation-water flow rate of 3.4 mL/min and an extraction time of 204 min. Analysis of variance (ANOVA) indicates that the generated second-order polynomial model was highly significant with R2=0.9589 and P<0.006. The gas chromatography-mass spectrometry analysis of essential oil extracted from the Ruta chalepensis L. aerial parts revealed the presence of 2-undecanone, 2-nonanone and 2-decanone as major components.

Abstract

The crude sweet whey is an effluent and a co-product of cooked and pressed cheeses and casein, released into the environment without prior treatment (case of Cheese Dairy Sidi Saada, Yellel, Relizane, Algeria) affect the quality of freshwater ecosystems (Oued Mina, Relizane, Algeria).Our study focused on the control of the physical and chemical parameters of crude sweet whey and delactosed whey.The results showed that the applied bioprocess modified the physical and chemical parameters of crude sweet whey such as :density,dry matter,refractive index,viscosity,ash,pH and electrical conductivity, acidity,proteins and lactose; for this purpose these findings depended on the operating conditions, and the composition of the whey put in treatment.

Abstract

The sedimentary sequences of the upper Miocene in the Strymon basin in Northern Greece are composed of sedimentary rocks and are separated on an entirely new lithostratigraphic shape. Fossil-fauna has been collected from specific parts of the described geological sections, which mainly include mollusks from Bivalvia and Gastropoda. From laboratory research on the micro-fauna and micro-flora a number of taxonomic units of Foraminifera were determined and representatives of Actinozoa, Bryozoa, Crinoidea, Ostracoda, Otolithus, Diatomeae and Charophyta were found, which give a more-complete biostratigraphical image of the sediments. Based on these investigations with the use of the biofacial analysis, through the study of palaeoecology data of the fossils, three basic types of palaeohabitat and development of organisms were identified and a new palaeogeographic interpretation of the depositional environments in the Miocene basin is given.

Abstract

The growing development of settlements in mountainous areas and their sustainable development constantly requires new approaches to assess the land in terms of occurrence of landslides. The flysch zone, where the monitored area is located, is one of the most landslide prone areas in Slovakia. Landslides respond sensitively to the quality of the individual factors that form the landscape and to the change of natural conditions. Their occurrence is a geo-barrier that reduces or totally prevents the use of natural environment and negatively affects the life of population and territorial development. The reason for the increased hazard of landslides is not only demographic pressure on territories, but also its poor management. Consistent spatial planning addresses not only the spatial layout but also the functional use of the territory. Landslides represent one of the limits of land use. This study is based on the assessment of landsliding as a limit to possible territorial development. The input parameters for the assessment were elements of the current landscape structure (built up structure, forest stands, transitional woodland-shrubs, traditional agricultural land, permanent grasslands and arable land) and occurring landslides (active, potential and stabilized). On most of the determined elements of the landscape, landslides occur on about a quarter of their area. They have a smaller share only in areas of mixed forests, built up areas and have the smallest share on arable land. Potential landslides have the largest proportion on all landscape elements. They occupy the largest areas on coniferous forests (1578.93 ha) and on permanent grasslands (741.33 ha). By evaluating the overall endangerment of the area by landslides according to the degree of threat, we found that the greatest threat of landslides is in the Skalité and Svrčinovec cadastral areas, the smallest threat is in the Čadca cadastral area. In addition to the danger of landsliding in the individual elements of the landscape, we have also set limits for its development. Spatial planning limits have been divided into two categories according to the sectors they affect the most: limiting the development of an area assigned for residential building, or restricting the development of an area designed for agricultural and forestry purposes.