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Abstract

Results of investigations on the patterns of distribution and dispersal of alien species of trees and shrubs in the territory of a steppe protected area, Yelanetskyi Step Nature Reserve (Mykolaiv Region, southern Ukraine), are presented. We registered within this protected area 10 alien woody species. For the most widespread ones (Ulmus pumila L., Gleditsia triacanthos L., Elaeagnus angustifolia L., Robinia pseudoacacia L.), we carried out ecological analyses. In order to establish the scope of impact of ecological factors upon these species, their specificity, and interdependence between ecological factors, the phytoindication method was applied (Didukh, 2012). The results of our analysis conducted on 12 main ecological factors (as outlined by Didukh, 2011), such as soil water regime (Hd), variability of damping (Fh), soil aeration (Ae), soil acidity (Rc), nitrogen content (Nt), salt regime (Sl), carbonate content in soil (Ca), thermoregime (Tm), climate humidity (Om), continentality (Kn), cryoregime (Cr), and light intensity (Lc), show that dispersal of model alien species does not have ecological limitation. However, E.angustifolia and R.pseudoacacia have the strongest capacity to penetrate the steppe communities, especially disturbed ones. Further dispersal of these alien species in the studied area and adjacent territories is hampered only by the integrity of the structure of steppe communities.

Abstract

This research concerns the complex problem of morphological transformations of villages in the intra-urban area (i.e. settlements incorporated into acity), as well as the suburban area, using the example of the metropolitan area of Łódź, Poland. The main aim of the research was to analyse the diversity of selected rural settlements and their spatial changes after World War II.. The study was based on preserved historical maps and today’s plans. An analysis of morphological changes of selected villages was conducted using graph theory methods. It was noticed that the graph development index should depend on the relative number of edges in relation to the number of nodes and the number of graph cycles, which express the degree of complexity of a settlement unit. Three main groups of villages, characterised by different scales of morphological transformations, were distinguished as a result of the study. Settlement units with orthomorphic transformations, where all spatial modifications were mainly additive and the initial layouts have been preserved almost completely, represent the first group of villages. The second group is composed of units with semi-metamorphic transformations, where the spatial reorganization was significant, but not total. The third group includes villages with metamorphic changes, where the initial layouts have been totallytransformed.

Abstract

Floating wind power platforms are in constant motion due to waves when deployed at sea. This motion directly affects the stability and safety of the platform. Therefore, it is very important to study the laws governing the platform’s dynamic response. In this paper, the dynamic characteristics of an offshore floating wind power platform were analysed under nine different sets of operating conditions using a numerical calculation method. Following this, a scaled 1:50 platform model was tested in a tank. Model tests were carried out with different wave conditions, and dynamic response data for the platform were measured and analysed. The hydrodynamic variation rules of floating wind power generation platform in waves were obtained. Some effective measures for maintain the stability and safety of wind power platforms are put forward that can provide a reference for dynamic stability research and the design of floating wind power platforms in the future.

Abstract

Oil palms are an important crop for Malaysia as the main crop cultivated from agricultural lands for economic purposes. The livelihood of small growers is, in fact, very dependent on that industry. The present study employs the application of remote sensing of higher resolution to assess the biophysical characteristics of oil palms stands for a plantation in Lenggeng, Negeri Sembilan, Malay Peninsula. Band combination with the use of natural, red, blue bands and red-edge spectrum was employed to obtain early information on the oil palm stands at the site. We subsequently employed fish eye camera to collect information on leaf area index at the field. The study also measured the height and diameter at breast height of all plots established in the site. Finally, correlation was performed to establish the relationships between height-to-leaf area index relations. Diameter at breast height measuring points was scattered at the upper part of the line that formed negative relationships (R2 = -0.0313). Height was positively associated with leaf area index, a bit weaker (R2 = 0.2323). Interpolation found plots at varying elevation level. Maximum height of the trees was recorded at the highest elevation in the site, presumably due to the higher solar radiation that enhances photosynthesis. Our study demonstrates the usefulness of the finding for implementation elsewhere in assessing the biophysical characteristics of oil palm trees. The study leads to further understanding of oil palms, specifically the biophysical characteristics associated with plant productivity assessment.

Abstract

The spatio-temporal monitoring and understanding of the pattern of land-use and land-cover (LULC) change in the Himalayas are essential for sustainable development, especially from environmental planning and management perspective. The increasing anthropogenic activities and climate change in the Siwalik and Lesser Himalayas have substantially experienced rapid change in the natural landscape; however, detailed investigation and documentation of such observed changes are limited. This study aims to assess the LULC changes along the Kalsi-Chakrata road corridor located in the Lesser Himalayan region of Uttarakhand state of India using remote sensing and geographic information system (GIS) for the periods 2000-2010 and 2010-2019. The LULC maps were generated from multi-temporal satellite images of the Landsat -7 Enhanced Thematic Mapper Plus (ETM+) series for 2000 and 2010, and the Linear Imaging Self-Scanning System IV (LISS IV) images from Resourcesat-1 for 2019. The extent of spatial landscape changes occurred in different LULC classes was performed through the cross-tabulation change matrix in the GIS module up to the individual village level. The results indicate that the forest cover of the area was intensively converted to open areas, sparse vegetation, and different land-use categories. These included agricultural land, built-up areas, and decreased from 47.27 % in 2000 to 36.66 % in 2019. During the same period, the open areas and agricultural areas were increased by 15.86 % and 4.49 %, respectively. Moreover, the built-up areas (both urban and rural settlements) were progressively increased from 0.33% in 2000 to 0.56 % in 2019. The conversion of forests and sparsely vegetative areas to agricultural land and rural settlements is closely associated with the increasing anthropogenic activities due to population growth, tourism, movement of heavy vehicles for mining and other economic activities. The changes in land-cover to land use classes are more prominent in Samalta Dadauli, Nithala, Bhugtari, and Udapalta villages located between Kalsi and Sahiya town. The reported maximum transition of forest areas into the open area, agricultural land, and sparse vegetation indicates the possible scarcity of water, which could link with the incidence of climatic or seasonal variation in the Lesser Himalayan terrain to the hydro-geomorphic and anthropogenic processes. The trend in LULC change at the village level gave the insight to help to prioritize future mitigation planning and sustainable development that are exceedingly convenient for the planners, policymakers, and local authorities for comprehensive forest management, biodiversity strategies, and necessary conservation

Abstract

In this work a search operation support system is presented, which is an additional autopilot function block. Its task is to lead a vessel included in the search by the SAR services to the datum position on the basis of the data entered by the operator into the system and then automatically to search the indicated area according to the newly defined search pattern. The set goal can be achieved thanks to the autopilot that guides the ship along a given trajectory consisting of straight lines and arcs. High control accuracy is provided by the IMC control system using a relatively simple non-linear ship model. The simulation tests of the tanker model confirmed that the indicated search area can be precisely checked in a shorter time than when using the expanding square search pattern.

Abstract

The paper presents the results of an experiment conducted on two cargo ships – a 5300 TEU container with a steam heating system and a 7500 dwt general cargo ship with a thermal oil system. On both ships research has been carried out using specially designed measuring equipment. After gathering data about flow velocity and temperatures (steam/ cooling water/ thermal oil/ seawater/ outside air), calculations have been done, resulting in histograms. For both types of histograms (heat demand and service time), the probability density function was fitted, using the K-S statistical test. The last step was comparison of the probability distribution mean to seawater and the outside air temperatures by linear regression and the coefficient of determination. The dependencies between the mentioned temperatures and heat demand were noted.

Abstract

This study deals with the analysis of changes in the secondary landscape structure of the territory of the Jeseniky Mountains (Czech Republic) monitored in the years 1946, 1953, 1962, 2000, and 2016. The study analysed georeferencing aerial geodetic images in the QGIS 2.18 program. On the basis of the land use classification key that was created, historical changes were identified in the following categories of land use; forest, arable land, orchards, water surfaces, wild life refuges and scattered greenery, river networks, permanent grass stands, meadows and pastures, gardens and built-up areas, courtyards and hard surfaces. The surface areas of land use categories were utilized for the calculation of change indicators regarding the structure of the landscape (landscape similarity index, coefficient of ecological stability, and change index). The maps for land use created for individual historical periods functioned as the starting point for a comprehensive assessment of the landscape by means of a SWOT analysis, which created the basis for a proposal for permanently sustainable utilization of the landscape in the area that was monitored. The study results indicate that the analysis of the historical development of the secondary landscape structure may be utilized as a decision support tool when planning sustainable landscape management.

Abstract

The increase of seakeeping performance is of particular importance for car and passenger ferries, service ships in the gas and oil extraction industry and offshore wind power farm industry, as well as for special purpose ships (including military applications). In the water areas of the Baltic Sea, North Sea, and Mediterranean Sea, which are characterised by a short and steep wave, the hull shape has a substantial impact on the operational capacity and propulsion efficiency of the ship, as well as on comfort and safety of navigation. The article analyses selected aspects of seakeeping for four variants of a selected case study vessel, indicating practical limitations of the strip method. The analysed aspects included hull heaving and pitching, added resistance, Motion Thickness Indicator (MSI), and Subjective Magnitude (SM). Experimental tests were also performed in the towing tank. Their comparison with the numerical results has indicated high inaccuracy of the strip method. What is more, the simplified representation of hull shape used in the strip method makes it impossible to analyse the effect of hull shape changes on the predicted seakeeping characteristics. Especially for the case of head wave, neglecting highly non-linear phenomena, such as slamming or head wave breaking, in strip method-based computer simulations will significantly decrease the reliability of the obtained results. When using the strip method, the seakeeping analysis should be complemented with model tests in a towing tank, or by another more complex numerical analysis, such as CFD for instance.

Abstract

The article deals with the contamination of soil in the vicinity of the D1 motorway caused by the application of chemical de-icing agents in winter. In the selected area, during a period of one year (from October 2017 to October 2018), soil samples were regularly collected once a month at five different distances from the road. Chloride concentrations in aqueous extracts of the soil were monitored and the degree of toxicity was established for the selected living organisms. The resulting chloride load was evaluated with respect to the precipitation activity and the amount of de-icing salt applied in the area. The highest concentrations of chlorides were found at a distance of 2 m from the road. At the distance of 20 m from the road, the concentration of chlorides in the soil was approaching the chloride concentration found in the referential background set for the selected locality. The concentrations of chlorides at the first three measured distances from the road corresponded to the quantity of de-icing salt applied and the precipitation activity recorded during the relevant months. The maximum concentrations were reached in April 2018. Ecotoxicological testing of aqueous extracts of soil did not confirm any significant toxicity to the selected living organisms. From the tested organisms, the white mustard was identified to be the most sensitive to this type of toxicity; the increased toxicity was observed only for aqueous extracts of soil samples collected at distances dI (0 m) and dII (1 m), thus, it could have been related to the increased concentration of chlorides during the relevant period.