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Eco-geographical variation in the diet of the Barn Owl (Tyto alba) in mountainous areas of France

Abstract

Because of the worldwide distribution of the Barn Owl (Tyto alba) and the easily way to find its pellets, it is often used to diet studies. To investigate the eco-geographical impact of mountainous areas on its diet, we conducted studies in the Jura, Alpes, Central and Pyrénées mountains and we also did pellet analysis from 8 sites in the Jura mountains. Analysis of the tooth and skull content of pellets allowed us to draw up two types of change in the diet of Tyto alba in correlation with mountain elevation. The first one concerns the Jura, Alpes and Central mountains, where the diversity of the diet declines with the increase in elevation. The second one concerns the Pyrénées mountains, where there is no change in the diversity of the diet, perhaps because of the higher diversity of small mammals caused by mediterranean influence. Thus, it seems that elevation cau ses a decrease in diet diversity of Tyto alba in continental mountains (Jura, Alpes and Central mountains) probably because of more homogeneous landscapes dedicated to grass production. However, in Mediterranean mountains (Pyrénées), a more diversified small mammal guild provides a constant level of diet diversity.

Open access
Optimizing the Shape of a Compression-Ignition Engine Combustion Chamber by Using Simulation Tests

Abstract

Modern solutions used in compression-ignition internal combustion engines are quite similar to each other. The use of high-pressure, direct fuel injection results in high combustion rates with controlled exhaust emissions. One of the combustion system quality criteria is to obtain adequately high thermodynamic indicators of the combustion process, which are obtained through, among others, the right combustion chamber geometry. Its shape influences the fuel atomization process, turbulence of fuel dose, evaporation and the combustion process. Optimizing the combustion chamber shape is one of the decisive factors proving the correct execution of the combustion process. This article presents the methodology of choosing the combustion chamber shape (changes of three selected combustion chamber dimensions) by using the optimization methods. Generating multidimensional data while maintaining the correlation structure was performed by using the Latin hypercube method. Chamber optimization was carried out by using the Nelder-Mead method. The combustion chamber shape was optimized for three engine load values (determined by the average indicated pressure) at selected engine operating conditions. The presented method of engine combustion chamber optimization can be used in low and high speed diesel propulsion engines (especially in maritime transport applications).

Open access
Impact of land use and geological conditions on selected physical soil properties in relation to the earthworm abundance and biomass along an altitudinal gradient in Slovakia

Abstract

The aim of the study was to analyse the impact of land use and altitudinal gradient including geological conditions on selected soil physical properties with subsequent effect on earthworms as important soil organisms. The research was conducted at three study sites (Očová – OC, Tajov – TA, Liptovská Teplička – LT) situated in the different climatic and natural conditions of Slovakia each with 3 plots differing in land use (arable land - AL, permanent grasslands – PG, forest land – FL). During 2014 over two periods, we measured soil penetration resistance (PR) with total depth of the measurement (DP) and soil moisture (SM). Earthworms were hand sorted counted and weighed. We found out high variability of measured parameters conditioned by time, space (altitudinal gradient) and land use. PR values of all measurements ranged from 0.19 to 5.00 MPa, DP values from 0.02 to 0.80 m and soil moisture from 2 to 50%. Paired samples test confirmed differences between different land use types mainly between AL and FL plots. There were confirmed significant differences between three ecological gradients in all observed properties with one exception. Correlations among observed variables under different altitudinal gradients and land use types were found. The earthworm density and biomass was significantly higher in permanent grasslands compared to forest and arable land. In arable land, the earthworm density and biomass negatively correlated with the penetration resistance and positively with the depth of the total measurements. In permanent grasslands earthworm biomass positively correlated with soil moisture.

Open access
Modelling of Technological Solutions to 4th Generation DH Systems

Abstract

Flue gas evaporation and condensing processes are investigated in a direct contact heat exchanger - condensing unit, which is installed after a furnace. By using equations describing processes of heat and mass transfer, as well as correlation coherences for determining wet gas parameters, a model is formed to create a no-filling, direct contact heat exchanger. Results of heating equipment modelling and experimental research on the gas condensing unit show, that the capacity of the heat exchanger increases, when return temperature of the district heating network decreases. In order to explain these alterations in capacity, the character of the changes in water vapour partial pressure, in the propelling force of mass transfer, in gas and water temperatures and in the determining parameters of heat transfer are used in this article. The positive impact on the direct contact heat exchanger by the decreased district heating (DH) network return temperature shows that introduction of the 4th generation DH system increases the energy efficiency of the heat exchanger. In order to make an assessment, the methodology suggested in the paper can be used in each particular situation.

Open access
Study of Hygrothermal Processes in External Walls with Internal Insulation

Abstract

Being an important contributor to the final energy consumption, historic buildings built before 1945 have high specific heating energy consumption compared to current energy standards and norms. However, they often cannot be insulated from the outside due to their heritage and culture value. Internal insulation is an alternative. However internal insulation faces challenges related to hygrothermal behaviour leading to mold growth, freezing, deterioration and other risks. The goal of this research is to link hygrothermal simulation results with experimental results for internally insulated historic brick masonry to assess correlation between simulated and measured data as well as the most influential parameters. The study is carried out by both a mathematical simulation tool and laboratory tests of historic masonry with internal insulation with four insulation materials (mineral wool, EPS, wood fiber and granulated aerogel) in a cold climate (average 4000 heating degree days). We found disparity between measured and simulated hygrothermal performance of studied constructions due to differences in material parameters and initial conditions of materials. The latter plays a more important role than material parameters. Under a steady state of conditions, the condensate tolerating system varies between 72.7 % and 80.5 % relative humidity, but in condensate limiting systems relative humidity variates between 73.3 % and 82.3 %. The temperature between the masonry wall and all insulation materials has stabilized on average at +10 °C. Mold corresponding to Mold index 3 was discovered on wood fiber mat.

Open access
Crystalline protein profiling and cry gene detection in Bacillus thuringiensis strains isolated during epizootics in Cydia pomonella L.

Abstract

The composition of Bacillus thuringiensis crystalline inclusions was characterized in 18 strains: 12 isolates were obtained from the intestinal tract of Cydia pomonella larvae during epizootics, 2 isolates were cultured from Leucoma salicis larvae taken from their natural populations, and 4 reference strains. The number and molecular mass of B. thuringiensis crystalline proteins (Cry and Cyt) was estimated by the sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). The crystals contained 1-8 proteins with molecular masses of 36-155 kDa. The toxin profiles differed both quantatively and qualitatively. The B. thuringiensis MPU B9 isolate had the highest number and diversity of Cry toxins. The analysis of crystal composition by SDS-PAGE was insufficient to detect groups and subgroups of Cry proteins. We identified 20 groups and 3 subgroups of Cry and Cyt crystalline toxins. Only one epizootic strain harboured cry25. In single reference strains, the cry1H, cry10 and cry25 genes were found. We did not find any correlation between the occurrence of cry genes and electrophoretic protein profiles of crystalline toxins.

Open access
Nest-site selection and population trend of Collared Pratincoles (Glareola pratincola) breeding in agricultural habitats of the Nagykunság region (Hungary)

Abstract

The Collared Pratincole (Glareola pratincola), which was once a typical breeding species of the sodic grasslands of the Great Plain, has become threatened with extinction from Hungary. It disappeared from the traditional grassland breeding sites before the 2000 and is currently breeding only in three sites in agricultural environments in Hungary. The objectives of our research were to find links between the use of shallow wetlands and the breeding behaviour of the species and to identify the characteristics of its breeding on ploughed fields. Data were collected between 2008 and 2016 as part of preparations for the conservation of the largest population which is found in the Nagykunság. We found a positive correlation between colony size and the area of the nearby wetland. We calculated the proportion of habitat-types used for nesting, and found that cultivated fields and fallow lands were the most important. Additionally, we also found that colony sizes were substantially smaller during the research period than those found earlier in the traditional grassland habitats. Finally, we found a positive trend in the size of the population during the research period.

Open access
Denoting the intensity of soil biochemical transition according to stand species composition

Abstract

The aim of this study was to denote biochemical soil activity in pure Scots pine, Norway spruce, silver fir, European larch, European beech and oak stands as well as in mixed fir-pine, beech-pine and fir-beech forests growing on a fertile fresh mixed deciduous site. The field work was carried out in the following Forest Districts: Nowe Ramuki (Mazursko-Podlaska forest region), Płońsk, Jabłonna, Brzeziny Siedlce, Grójec (Mazowiecko-Podlaska forest region) and Skarżysko, Ostrowiec and Marcule (Małopolska forest region). In 2015–2017, sample plots were assigned and chemical as well as soil enzyme activity measurements were made in each forest stand. Samples were taken from the organic (O) and humus (A) layers and for both the acidity (in 1M KCl), content of nitrogen, carbon, sum of exchangeable alkaline cations and hydrolytic acidity were determined. The investigation of soil enzymes included the measurements of urease, asparginase, acid phosphatase and dehydrogenase activity. Coniferous trees, especially fir, spruce or larch, and mixed fir-beech and pine-beech stands were observed to have a very positive influence on the biochemical soil properties. The highest activity of dehydrogenase was observed in soils of spruce and mixed fir-beech stands, whereas it was lower in soils of beech and pine stands, and the lowest in oak stands. Oak stands were furthermore characterized by the lowest soil acidity, lowest concentration of alkaline cations, the lowest nitrogen and carbon content as well as the smallest C/N ratio. In overall, soil enzyme activity showed a significant correlation with chemical soil parameters.

Open access
Soil types specified in the bonitation classification and their analogues in the sixth edition of the Polish Soil Classification

Abstract

The aim of the paper was to present the correlation between soil types specified in the sixth edition of the Polish Soil Classification (SGP6 2019) and Polish bonitation classification. The comparisons included two categories of agricultural land: arable soils and soils of permanent grasslands. In Poland bonitation maps are one of the oldest documentations regarding soil cover. They were elaborated in an uniform manner and based on the field examination of soil profiles. Soil information reflected specific rules adopted in the soil quality classification, including identification of soil types based on genetic criteria and recognition of appropriate sequence of specific horizons in the soil profile. Publication of the sixth edition of the Polish Soil Classification enabled the attempt to adjust soil units (soil types) specified in both systems. Despite the distinction of new soil units in the Soil Classification of Poland (SGP6 2019), the usage of bonitation maps and classification protocols should not pose major difficulties in reinterpretation of soil types. This indicates on the possibility to introduce, similarly to year 2012, the terminology adapted to the requirements of modern soil science knowledge without causing significant changes in the soil-valuation table.

Open access
The Energy Efficiency Gap in Turkish Maritime Transportation

Abstract

The Turkish Merchant Shipping Industry has recently witnessed an increasing awareness of the importance to minimize environmental pollution and fuel oil consumption. Together with certain non-governmental organizations and media concerns about environmental protection, the International Maritime Organization (IMO) has been strict on controlling undesirable effects on the environment and, consequently, forcing shipping companies to minimize their emissions. Besides, today’s highly advanced technology companies over the world have developed various innovative systems that can be utilized to minimize carbon emission, thus giving assurance to relevant investors that their investments are most likely to turn out well with a considerable financial gain in the short or long term. Despite all such favorable developments, in a general look, shipping companies seem reluctant in making use of technologies providing efficiency in energy consumption. This reluctance has eventually brought about the term “Energy Efficiency Gap”. This research conducts a questionnaire, created by Acciaro et al. [1], among the shipping companies in Turkey. 20 respondent companies, who represent 26 percent of the Turkish owned merchant marine fleet of over 1000 gross tonnage in terms of deadweight cargo capacity, participated in the research. The Pearson correlation analysis was used, and interpretations were made according to the obtained statistical values. The aim of the research was to identify reasons and points restraining the use of new technologies regarding energy efficiency, as well as to develop proposals for the innovators in this field about how to overcome this handicap concerning technical and managerial aspects of gaining energy efficiency.

Open access