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Abstract

The choice of suitable biodiversity assessment methods for practical purposes in city planning and decision-making is still a challenging problem. Despite the availability of a wide variety of methods for almost all dimensions of diversity (mainly species and habitat diversity, including spatial aspects), few of them have entered the practical ‘daily’ work. In the example of in-depth examinations in German and Czech cities (e.g., Dresden and Liberec), it was found that the most frequently applied analyses are those of protected species and habitats in urban nature conservation in general, and particularly in city development planning to derive avoidance, protection and compensation measures. Preference analyses (questionnaires, structured interviews) are becoming increasingly popular. Economic calculations of habitat values and the valuation of ecosystem services are still in their infancy. We will present methods that are presently being applied or could be included in a practical methodological toolkit to analyse and valuate biodiversity in urban nature conservation, city planning and decision-making.

Abstract

This study is focused on the evaluation of the values of the diversity indices of semi-natural dry calcareous grasslands of the Festuco-Brometea class in the area of Devínska Kobyla National Nature Reserve 50 years after abandonment of traditional management (grazing and mowing). The values of the species richness, the Shannon–Wiener index of diversity, the Simpson index, and Pielou’s measure of species evenness in the communities in the old and recent data, and the values of the environmental variables based on the Ellenberg indicator values of species were analyzed. For most of these analyses, we used Kruskal–Wallis in R 3.5.1. Compared to the past, we have recorded a significant lower values of the species richness, biodiversity, and species evenness in some communities. In some communities, no significant changes were recorded. Only in one community—Poo badensis-Festucetum pallentis, the higher values of Shannon–Wiener index was recorded compared to the past. The analysis of the Ellenberg indicator values revealed a statistically significant higher Ellenberg indicator values for moisture and nutrients and lower values for light in more recent period compared to the old period. The recorded results could be caused by the changes in the management after the year 1965, after abandonment of grazing and the gradual overgrowing by woody species took place in the area. The frequency of occurrence of some woody species (e.g., Populus alba, P. nigra, and Robinia pseudoacacia) in some communities increased compared to the past.

Abstract

In terms of spatial planning and environment protection procedures in Croatia, geomorphological features as a component of geodiversity are mostly considered marginally. They are considered locally in the scope of certain operations such as urban development, mining, or activities that are being assessed in the environment impact assessment procedures or spatial and strategical planning. Regarding the protection and the planning processes connected with it, geomorphological features should be considered in the right scale and with all of its values and services that are being provided to the environment on a landscape scale. In this paper, geodiversity and its role in landscape evolution will be connected and explained with the example of subgeomorphological region Ogulinsko-plašćanska Zavala, in the mountainous Dinaric karst part of Croatia. As it has been a region with long human and nature interaction, and a region with preserved natural and seminatural landscapes, it is a suitable area for such an analysis. In order to properly assess the geomorphological features as one of the determinants of landscape, the basis for environment impact assessment procedures and spatial planning procedures, geoecological analysis of geodiversity and landscape services occurrence and spatial distribution is carried out.

Abstract

The soil aggregation and structure, water stability of aggregates, and peculiarities of microstructure formation of the ravine forest soils in Dnipropetrovsk region on the example of the northern variant of the ravine forest “Kapitanivskiy” have been identified. The soil properties of southern and northern ravine exposures have been compared. The soil structure, aggregate composition, water stability of aggregates as well as soil-forming processes of the ravine ecosystem have been analyzed. Micro-morphological studies have shown a high degree of aggregation of the upper (0–60 cm) horizons of the soil profile. The structure-forming process is of a zoogenic origin. Aggregates of coprolite nature contain well-disintegrated plant remains. Dark gray, almost black color along the entire area of the micromorphological slide is due to a large amount of organic compounds, which indicates active processes of humification. Fine-dispersed humus consists of a large number of evenly spaced humus clusters. The type of humus is mull. The skeleton consists of minerals of various sizes, dominated by quartz and feldspars. Plasma is humus-clay, homogeneous throughout the entire slide, anisotropic with speckled glowing. Microstructure is mainly aggregated and, in some places, spongy, depending on a microzone of the soil slide. Elemental microstructure is of plasma-silty type. The area of the visible surface of the pores in the upper horizons of the soil profile is fairly large (40%). Pores are round and elongated, of regular shape, here and there with remains of small invertebrates. The deeper the soil slide is, the smaller the area of visible pores along with aggregation becomes. Correlating with micromorphological characteristics, water resistance of structural aggregates reaches very high (90.01% ± 3.07) values in the upper horizons of the soil slide, decreasing at depths. The coefficient of pedality is rather high (7.83 ± 0.81) in the upper horizons, decreasing at depths.

Abstract

Soil organic carbon (SOC) in agricultural land forms part of the global terrestrial carbon cycle and it affects atmospheric carbon dioxide balance. SOC is sensitive to local agricultural management practices that sum up into regional SOC storage dynamics. Understanding regional carbon emission and sequestration trends is, therefore, important in formulating and implementing climate change adaptation and mitigation policies. In this study, the estimation of SOC stock and regional storage dynamics in the Ondavská Vrchovina region (North-Eastern Slovakia) cropland and grassland topsoil between 1970 and 2013 was performed with the RothC model and gridded spatial data on weather, initial SOC stock and historical land cover and land use changes. Initial SOC stock in the 0.3-m topsoil layer was estimated at 38.4 t ha−1 in 1970. The 2013 simulated value was 49.2 t ha−1, and the 1993–2013 simulated SOC stock values were within the measured data range. The total SOC storage in the study area, cropland and grassland areas, was 4.21 Mt in 1970 and 5.16 Mt in 2013, and this 0.95 Mt net SOC gain was attributed to inter-conversions of cropland and grassland areas between 1970 and 2013, which caused different organic carbon inputs to the soil during the simulation period with a strong effect on SOC stock temporal dynamics.

Abstract

Cultural ecosystem services (CES) are mainly intangible benefits, obtained by aesthetical and other experiences, recreation, learning and spiritual enrichment, or by the ability to distinguish values. In other words, what makes a service ‘cultural’ is its ‘non-economical’ character. CES are ecosystem services with direct impact on the quality of life in urban systems, and they are directly appreciated by inhabitants and visitors of these urban systems (Plieningeret al., 2013; Zulian et al., 2018). In order to satisfy the needs and expectations of the wider urban community, a ‘broader portfolio of areas’ is needed, which can meet the expectations of different users, from children to older adults. The new methodological approach tested on three model areas in the city of Nitra in the housing estate Chrenová was used to establish the level of benefits provided by existing vegetation areas in urban environment in terms of recreation as a CES. Following data were collected: the quality of vegetation, spatial design, management of vegetation elements, selected environmental aspects, available amenities and architectural elements needed for recreation. In our article, we present the assessment of vegetation in relation to the provision of recreation as a CES. Our results show that the assessed areas can be classified in the category of average to low provision of benefits related to recreation. Vegetation on area P1 is in good condition, mainly the quality of trees and shrubs was assessed as very good (4). Other areas (P2 and P3) assessed provide only low levels of benefits derived from recreation as one of the CES. This was caused by some vegetation deficiencies (mainly related to horticultural and compositional aspects). Methodological approach can be used for different vegetation areas in urban environment and after suitable modifications (e.g. adding other components for assessment) also for different cultural ecosystems services. The results can be used in landscape planning documents or in other types of documents dealing with the quality of vegetation in urban environment.

Abstract

The countries of the European Union have joined, inter alia, soil protection in the Common Agricultural Policy (hereinafter referred to as CAP). Accelerated soil erosion is a problem resulting from inappropriate land management, which affects both the presence of organic matter and the soil structure. The tool for elimination of negative impacts on soil can be its sustainable use. This requires the use of an accurate system to improve its condition. The first step should be problem identification and localisation. The research is aimed at the identification of water erosion risk areas by using selected methodological procedures. The research area was located at the intensively used hilly land of the Southwestern Slovakia. The digitisation of the manual interpretation of erosion risk areas with the use of aerial photos, erosion modelling, chemical analysis of soil organic matter (SOM) and analysis of soil structure were used. Verification was implemented via the field research with the use of the soil probes. Methods affirmed significant presence of the water erosion in the area. Efficient identification of erosional processes is possible via combination of presented methods by taking into consideration geological, geomorphological, pedological and geographical conditions and the use of the area over a longer period of time. The results of using methods that ensure accurate and effective localisation of erosion surfaces can be used for sustainable land use and its conservation.

Abstract

To solve the nonlinear control problems of the unknown time-varying environmental disturbances and parametric uncertainties for ship course-keeping control, this paper presents an adaptive self-regulation PID (APID) scheme which can ensure the boundedness of all signals in the ship course-keeping control system by using the Lyapunov direct method. Compared with the traditional PID control scheme, the APID control scheme not only is independent of the model parameters and the unknown input, but also can regulate the gain of PID adaptively and resist time-varying disturbances well. Simulation results illustrate the effectiveness and the robustness of the proposed control scheme.

Abstract

The Stirling engine is a device in which thermal energy is transformed into mechanical energy without any contact between the heat carrier and the working gas enclosed in the engine. The mentioned feature makes this type of engine very attractive for the use of the recovery energy taken from other heat devices. One of the potential applications of Stirling engines is the use of thermal energy generated in the ship’s engine room for producing electricity. The work presents the concept of the Stirling engine type alpha powered by the recovery energy. The model of Stirling engine developed in this work allows a quantitative assessment of the impact of the design features of the engine, primarily the heat exchange surfaces and the volume of control spaces, on the achieved efficiency and power of the engine. Using an iterative procedure, Stirling engine simulation tests were carried out taking into account the variable structural features of the system. The influence of the size of the heater and the cooler, as well as the effectiveness of the regenerator and the temperature of the heat source on the efficiency and power produced by the Stirling engine have been presented.

Abstract

Implant treatment is a proven method in dentistry for partial and complete missing teeth reconstruction. In some clinical situations it is advisable to limit the number of implants, which can be obtained by making a bridge connecting the patient’s own tooth with the implant. So far, the possibility of using safe and permanent connections of natural teeth with implants has been examined to a small extent due to the dangers resulting from the different mobility of dental implants and teeth.

An attempt was made to use vibro-acoustic techniques to evaluate various combinations of teeth and implants. Pilot studies were carried out on cadavers-pig mandibles with implants. There were recorded sounds in the immediate vicinity of the mandible formed in response to impulse excitations carried out with a point hit against a tooth or implant before and after their joining with a bridge. The comparison of spectra allows to see features indicating a high probability of being able to distinguish between the examined configurations.

The results of the research should contribute to a better understanding of the mutual relations between the dental implant and the tooth, which are included in bridge. In the perspective, it will enable to assess the level of safety and to identify clinical situations that allow to obtain dental bridges based on teeth and implants.