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Abstract

Woody biomass feedstock is suitable for direct combustion, gasification, pyrolysis, ethanol or methanol production yielding heat, charcoal, pyrolysis oil, green electricity and bio-propellants. However, there are several issues concerning the environmental, social and economic sustainability of woody biomass production connected to land use, protection of wildlife habitats, conservation and remediation of landscapes. Establishing energy plantations on arable lands or on grasslands is generally considered as working against nature conservation, while setting them up in polluted areas or wastelands could be advantageous for wildlife, because of 1. more permanent cover that provides shelter and biomass for feeding, which is especially important in winter periods; 2. higher architectural complexity of vegetation providing more place for nesting and feeding for wildlife; 3. exploiting the advantages of root filtration, phytoremediation, or using less chemicals; 4. forbs in the undergrowth and young shoots able to provide better quality food for wildlife than the intensive monocultures. The solution is a complex management system, including land use, phytoremediation, waste and wastewater management and ecosystem-based planning incorporated in one dynamic structure.

Abstract

In this work, the calorific value content in the dry matter of the Scots pine (Pinus sylvestris L.) trees was evaluated. This dry matter was obtained only from the above-ground fractions of its biomass. Our experimental material was taken from five Scots pine trees situated in Slovakia. Wood and bark samples were obtained from the discs which were cut off from three locations, namely from the stem, branches of tree crowns and needles. Then, calorific value capacity (J g−1) in the dry matter of each sample was determined. The impact of statistically significant factors on the calorific value capacity was determined by means of analysis of variance. The average values are, according to the fractions, approximately in the range of 20,000–22,200 J g−1. The smallest capacity of the calorific value, approximately 20,000 J g−1, has the dry matter from bark obtained from the middle and crown parts of the stem. Then, the dry matter from stem wood and branches follows with a value of approximately 20,700 J g−1. Then follows dry matter of the coarse bark occurring on the stem butt and twigs that are covered with needles with a value of about 21,900 J g−1; and finally pine needles with the highest values of about 22,200 J g−1. The calorific value variability is relatively low with coefficients of variations of 0.9–2.8%.

Abstract

Ageing of biochars in soil affects their surface properties and can cause changes in water vapor adsorption-desorption processes. Measurements of hygroscopic water contents and corresponding water potentials of non aged and 3-year aged biochars as well as of sandy soils with medium and high quality were carried out during 5 cycles of water vapor adsorption-desorption processes at a room temperature of 23.5 °C. The results showed a significantly lower content of maximum hygroscopic water in the aged biochars than that in the non aged biochar at the end of water vapor adsorption processes at high air humidity. A significantly higher affinity of the high quality soil to water vapor resulted in insignificant differences in the maximum hygroscopic water content and in significant changes in the corresponding water potentials as compared to the same properties of the soil with medium quality. Minimum content of hygroscopic water was significantly lower in the non aged biochar than in the aged biochars at the end of the water desorption processes at ambient laboratory atmosphere. There were insignificant differences in minimum contents of hygroscopic water and in the corresponding water potentials of the aged biochars from soils with medium and high quality.

Abstract

In this paper we investigate the effects of biochar alone and its reapplication and combination with N-fertilizer (1) on the soil pH, and (2) sorption parameters. The soil samples were taken during growing period in 2018 from plots with different biochar (first application in 2014 – A, reapplication in 2018 – B) at application rates: 0 t.ha−1 (B0 control), 10 t.ha−1 (B10) and 20 t.ha−1 (B20) and different nitrogen fertilization: N0 (no nitrogen) and N40 (40 kg.ha−1). Our results showed that the first application of biochar at the rate of 20 t.ha−1 (B20A) without N-fertilizer significantly increased the values of soil pH in H2O, soil pH in KCl, the sum of base cations (SBC) and cation exchange capacity (CEC) compared to control (B0). Similar effects were observed also after reapplication of biochar (B10B). All investigated parameters in fertilized control treatment (B0N40) were worst and the first application, as well as the reapplication of biochar with N, caused significant increase of soil pH in H2O, soil pH in KCl, SBC, CEC, BS and decrease of hydrolytic acidity.

Abstract

Increasing food demand and decreasing water resources have composed a kind of pressure to find new technologies for efficient use of water and fertilizers in agriculture. Drip irrigation can be able to save irrigation water from 30% up to 50% in case it is properly designed, installed and operated compared to surface irrigation, and it can also enable increasing crop yields and crop quality. In order to get the highest benefits using drip irrigation, some soil data (infiltration rate, soil texture and soil structure), crop characteristics (row space, plant density, canopy cover, root system, crop species, crop variety) and water resources properties (water quality, surface or well water) must be considered in drip system design, management and operation. Fertigation is basically an agricultural technique and application together with water and fertilizer to soil and/or plants. It increases both yield and fertilizer use efficiency; therefore, leaching of nutrients is prevented. In order to utilize fertigation successfully, the four main factors must be considered: (i) the consumption rate of water and nutrients throughout the growth season that result in optimal yields, (ii) response in uptake of different crops to nutrient concentration in the soil and soil solutions, (iii) monitoring for total soil water potential, nutrients concentration in soil solution and % elements in plants as a function of time and (iv) root mass and distribution in the soil for given irrigation regimes and soil types.

Abstract

The aim of the paper is to draw attention to consequences of the transfer of competency at the level of the building procedure from state authorities to municipal offices in the Slovak Republic and the Czech Republic. The defined research objective was achieved firstly by conducting controlled interviews with representatives of the building offices in the Nitra Region and, secondly, by analysis of financing of this competency from the obtained data from publicly available sources in both states. Secondly, the paper includes a comparison of the financial management of the transferred competencies at the level of the building procedure between the Nitra Region (Slovakia) and the Pardubice Region (Czech Republic). By conducting controlled interviews in the Nitra Region, we came to the conclusion of the financial under-dimensioning of this competency. By comparing the amount of state subsidies provided for the building procedure in both regions, significant differences were found. Based on our research findings, we recommend reassessing the state subsidies for the transferred competency in the field of building procedure.

Abstract

The aim of this contribution was to outline the decision procedure for selecting potential sites suitable for installing sediment traps in vegetation buffer strips in the Fugnitz catchment, Austria. The selection procedure consisted of GIS data processing where the contributing areas of specific sites were specified according to the selected criteria (i.e. slope above 2°, vegetation strip in between agriculturally used land and river network, contributing area of at least 300 m2). Available landuse maps were updated with formerly not-digitized structures potentially influencing connectivity (e.g. ephemeral streams and road ditches) which were mapped in the field. From 31 pre-defined sites 15 were selected, taking into account as additional selection criteria the slope angle, soil erodibility and size of the contributing area. Two sites were selected for further investigations – i.e. installation of the sediment traps in vegetation filter strips collecting event-based sediment yields from adjacent arable fields. We conclude that GIS analysis has shown to be useful for the first step-delineation of potential sites of interest on the catchment scale. However, field-based surveys have been shown to be inevitable to obtain on-site information on vegetation characteristics and fine-scale topographic and management information.

Abstract

Soil erosion is a very common phenomenon encountered at many sloped earthen geotechnical structures. For instance, the surface soil of an inclined landfill cover system undergoes the erosion due to various adverse atmospheric variants. This is one of the major causes for performance failure in the cover system. However, previous researchers have rarely conducted the study for field assessment of soil erosion in high rainfall tropical regions such as northeast India. The literature advocates the utilization of vegetation for erosion management. This study investigated the impact of vegetation growth on soil erosion of a cover surface layer under both natural and controlled artificial rainfall. The soil erosion was monitored by collecting the soil loss due to rainfall. Vegetation growth was evaluated based on photographic image analyses. The study clearly indicates that the vegetation growth can contribute to reduction of soil erosion from the landfill cover surface.

Abstract

In the light of climate changes and in order to achieve stable crop production, irrigation represents an inevitable measure. Apart from water quantity, water quality represents a matter of concern. The paper elaborates on the presence of iron and manganese, as the main factors of causing the clogging of irrigation systems. The examined well water samples were taken mainly from Serbia. Photometric methods were applied for determining iron and manganese, and sensors for pH and conductivity. The obtained values were later subjected to a classification for irrigation water and the well water samples were classified according to the given thresholds. Precise location and presentation of the obtained results were done using the Geographic information system. The research has shown that from the analysed well water, only in 6 samples iron concentrations were increased up to a level classified as “extreme restrictions,” 4 samples as “warning,” while 31 samples of water were “adequate for irrigation.” Concerning manganese, in only one sample water was classified as “extreme restrictions,” in 14 as “warning” and in 26 as “adequate for irrigation.” pH and conductivity did not coincide with elevated concentrations of iron and manganese, but in the cases of exceeding thresholds, special attention should also be paid to these parameters.

Abstract

There are many methods used for soil water content measurement which we can divide into direct gravimetric methods from using soil samples or indirect methods that are based on the measurement of another soil property which is dependent on soil moisture. The paper presents the findings of volumetric water content measurements with gravimetric and time domain reflectometry (TDR) methods. We focused on four variants in the field experiment in Dolná Malanta (Slovakia): control variant (B0+N0), variant with biochar at dose 20 t.ha−1 without N fertilizer (B20+N0), variant with biochar 20 t.ha−1 and N fertilizer 160 kg.ha−1 (B20+N160) and variant with biochar 20 t.ha−1 and N fertilizer 240 kg.ha−1 (B20+N240). TDR is nowadays a well-established dielectric technique to measure volumetric water content; however, its accuracy is influenced by high concentration of salts in soil. In this paper, we evaluated the effect of added N fertilizer on the measuring accuracy of HydroSense II device that is operating under the TDR principle.