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Abstract

Drainage and peat extraction may have a negative impact on existing hydrological conditions and, consequently, on the conditions of wetland ecosystems. The aim of this study was to assess human impact on the studied Trzcińskie Mokradła Peatland by comparing the concentrations and trace element (Pb, Zn, Cu, Cr and Ni) pools in the study area (extracted vs. non-extracted areas of peatland). The concentration of trace elements in organic soils and their pools were analysed in relation to their depth in the soil profiles, content of organic matter, soil pH values and the degree of decomposition of organic materials (peat, mursh). Fifteen soil profiles (90 samples) were examined. The total soil elements content was determined after digestion in a mixture of HCl+HNO3. The element pools were calculated and expressed in g m−2 of soil in 0–30 cm and 30–50 cm layers. Soils showed acidic or slightly acidic reactions. The high concentrations of Pb and Zn were mainly observed in the upper horizons. The deeper layers enriched with mineral fractions were also enriched in metals like Cr and Ni.

Abstract

The aim of this study is to differentiate old-field plant communities along the abandonment time and/or environmental gradient in the landscape surrounded villages with established Czech settlers in Romanian Banat area conserving traditional agriculture, and to identify site factors which cause plant diversity of particular vegetation types. Study area: Wider territory centered by the village Sfânta Elena, southern Romania ((44°40’ N; 21°43’ E). Methods: We collected 97 phytosociological relevés covered the same number of old-fields in the area and the following habitat parameters were measured: soil pH, available phosphorus, total carbon and nitrogen, Heat Load Index. Software TURBOVEG / JUICE was used to collect and elaborate the data set of relevés. Old-field vegetation was classified into five basic plant communities using TWINSPAN (all the botanical material includes 291 plant species). For each community, we detected diagnostic species according to their fidelity index. The presence of mowing, grazing or burning was registered for recorded stands. Ecological preferences of each community were examined using one-way analysis of variance (ANOVA). Vegetation-environment relationships were analysed using ordination method – Cannonical correspondence analysis (CCA) in CANOCO for Windows (version 4.5) to find the main variability gradients within the dataset. Scatter plot relationships between variables were constructed. Main results and conclusions: Dependence of number of species (alpha diversity) on the abandoned field’s age exhibits an unimodal shape of this relationship with the maximum peak of species diversity in plant stands aged approximately 13 years. The most importnat ecological factors and/or type of management in the relationship to the old-field plant composition show the following significance order: available phosphorus content in the soil (P), total nitrogen content in the soil (N), presence of burning, length of abandonment (old-field age), carbon/nitrogen ratio in the soil (C/N). Other parameters (grazing, mowing, zero management) do not demonstrate effective impact according to our dataset and seem to be equal to the absence of burning.

Abstract

Archaeological research in the area of the chateau park uncovered the relic of the Gothic church of St. Elisabeth, dated to the second half of the 13th century. It is a single-nave building with a rectangular finish (length 25 m, boat width 13 m, presbytery width 10.5 m). The church probably had an older predecessor - a wooden structure on a stone foundation, dating from the mid-13th century. At the same time, the church site was a burial place: a grave of a young woman and a 1.5-year-old child, dated 13th/14th century were found outside the presbytery wall. In the presbytery, there were 3 graves of men dating back to the 14th century. It is very likely that these are the Lords of the Wallenstein family. Archaeological research in graves in the Church of St. Elisabeth unearthed a small collection of animal bone remains. The occurrence of bones of young and mature cattle and domestic fowls, which are abundant in the archaeozoological assemblage, indicates the prevailing meat consumption of these animals. The butchering marks on their bones document removal of meat from the carcasses.

Abstract

The present study deals with the estimation of the evolution tendency of the environmental stage of a protected habitat with predominant forest vegetation, during a short period of time, using techniques specific to remote sensing. Therefore, two important spectral indexes were tested while assessing the health of the forest ecosystems: i.e. the Normalized Difference Vegetation Index (NDVI) and the Structure Insensitive Pigment Index (SIPI). The period of time taken into consideration for the study was, 2013 - 2019, having used medium resolution satellite photos, Landsat 8 OLI, having initially undergone standard pre-processing operations (resize data, radiometric calibration, atmospheric correction). The satellite images modified according to the Top of Atmosphere Reflectance and corrected topographically resulted into getting values for the two before mentioned indexes. The quantity-spatial results obtained, correlated to the monthly values of the precipitations processed in order to obtain the SPI (Standardized Precipitation Index), mostly reveal, in what SIPI and also NDVI are concerned, a slight decrease in the quality of the forest on the analysed area in the sense that the vegetation stress is increased under meteorological factors, expressed differently depending on the morphometric and pedological parameters of the habitat.

Abstract

The use of cartographic sources and methods are the basic tools of historical geography. One of the main research trends in this field is the analysis of the spatial layout and number of old settlement units. The confrontation of maps with historical data allows the drawing of a town’s area at a certain time to be studied. The retrogression (R) and progression (P) methods that are currently used are imperfect and the model created (map) is usually incomplete and its reliability is limited. In the author’s opinion, the joining of retrogression and progression (a new method; combined – K)1 increases the quality of cartographic reconstruction of natural and cultural landscapes. The use of basic mathematical methods from the scope of set operations means the component reliability of the researched cartographic model can be varied because the common part of the retrogression and progression cartographic model represents mutual verification of source data. Quantitative effectiveness assessments of retrogression (R), progression (P) and the combined method (K) can be made for countable elements (e.g. buildings). As part of the conducted study, the effectiveness of separate methods was calculated: R = 76% for retrogression, P = 59% for progression and K = R ∪ P = 85% for the combined method. The mutual verification of the methods (R ∩ P) included 45% of residential buildings. The author describes the proposition of a new method and the course of verification research.

Abstract

Productivity is a significant aspect of construction industry that plays vital role for success and failure of any construction project. This industry generates 11% to 13% of GDP all around the globe and the cost of labour in any building project is 20% to 35% of the cost of Building. On daily basis labour utilizes 30% of time on productive activities rest 70% of the time is ruined in non-productive activities, there are multi factors which are affecting the labour production in construction industry hence this study provides an overview of productivity, Total Factor productivity, method used to measure accurate productivity in construction projects. The objective of this study is find out percentage up to what extent labour production is affected due to weather conditions, however this study is carried out in arid climate region in Month of June 2018, where minimum temperature was recorded 26.0 Celsius degree at 7:30 AM and Maximum was 47.80 Celsius degree at 3:00 PM. A descriptive survey research design approach was adopted using continuous observation method of study. Project work study manual served as the research instrument to collect the data on selected building sites for 30 working days. Data collected were analyzed using descriptive statics. The results show that average monthly production of mason gang was recorded with less production of 28.759%, Carpentry gang with average monthly loss of production 16.74% & steel fixer gang had average monthly loss of production was 12.188. This concludes that prior to signing the contract for construction project. The location, environment, topography of region, capacity of construction operatives must be kept in mind to decide the proper timeline for the successful of project.

Abstract

Palynological study of two Paleogene core sections from the Voronezh and Rostov regions (SW Russia) and one outcrop in Ukraine revealed the presence of a new Late Paleocene–Eocene species, Carpatella rossica sp. nov. The new species is attributed to the genus Carpatella because of the presence of both apical and antapical horns. However, it is suggested that the taxon represents some features transitional between the three genera of the “Aptiana–Ventriosum complex” of Helenes (1986). Based on the observation of a thin smooth inner layer of the wall in some specimens of Carpatella rossica sp. nov., and given some morphological features of other species described after 1988, a new emendation of the genus Carpatella (Grigorovich 1969) Damassa 1988 is proposed here.

Abstract

The authors’ main goal is to highlight the additional research potential of the method of analysing changes in the routes and names of streets introduced by Paweł E. Weszpiński in 2012. The proposed method was based on the old city maps of Warsaw and, according to Weszpiński, described “wandering streets and their names”. Taking the changing routes and names of streets on Lublin city maps from the last century as the research subject, the authors demonstrate that the method can be used to analyse how urban spaces are perceived and how they function in the minds of local residents. The authors propose to modify the method by adding one more important factor – the function of the place or street affected by the “wandering”. They claim that the study of changes in streets’ topography, territorial scope and names should be supplemented each time with an analysis of the administrative, economic or social significance of the place.

Abstract

Autonomous underwater gliders are buoyancy propelled vehicles. Their way of propulsion relies upon changing their buoyancy with internal pumping systems enabling them up and down motions, and their forward gliding motions are generated by hydrodynamic lift forces exerted on a pair of wings attached to a glider hull. In this study lift and drag characteristics of a glider were performed using Computational Fluid Dynamics (CFD) approach and results were compared with the literature. Flow behavior, lift and drag forces distribution at different angles of attack were studied for Reynolds numbers varying around 105 for NACA0012 wing configurations. The variable of the glider was the angle of attack, the velocity was constant. Flow velocity was 0.5 m/s and angle of the body varying from −8° to 8° in steps of 2°. Results from the CFD constituted the basis for the calculation the equations of motions of glider in the vertical plane. Therefore, vehicle motion simulation was achieved through numeric integration of the equations of motion. The equations of motions will be solved in the MatLab software. This work will contribute to dynamic modelling and three-dimensional motion simulation of a torpedo shaped underwater glider.