A 5‐yr cropping system experiment was initiated in 1981 to study transition from a conventional agricultural system using pesticides and fertilizers to a low‐input system. The site was primarily Comly silt loam (fine‐loamy, mixed, mesic, Typic Fragiudalf) with 12% Berks shaly silt loam (loamy‐skeletal, mixed, mesic, Typic Dystrochrept), and a small area of Duffield silt loam (fine‐loamy, mixed, mesic, Ultic Hapludalf), in Berks County, eastern Pennsylvania. Three 5‐yr rotations were compared. A conventional corn (Zea mays L.)‐soybean [Glycine max (L.) Merr.] rotation (designated “conventional”) was compared to two low‐input rotations which utilized oat (Avena sativa L.), red clover (Trifolium pratense L.) and winter wheat (Triticum aestivum L.), in addition to corn and soybean. One low‐input rotation used cattle manure as a nutrient source and produced forage crops in addition to cash crops (designated “low‐input/livestock”), while the other used legume crops as a nutrient source, and produced a cash crop every year (designated “low‐input/cash grain”). Corn grain yields in the low‐input systems were 75% of conventional in 1981 to 1984, but yields were not significantly different in 1985. Weed competition and insufficient N limited low‐input corn yields during the first 4 yr. Soybean yields in the low‐input systems were equal to or greater than conventional all 5 yr. It is concluded that a favorable transition from input‐intensive cropping to low‐input systems is feasible, but only if crop rotations are used which include crops that demand less N and are competitive with weeds, such as small grain, soybean, or legume hay. Corn should be avoided for the first 3 to 4 yr.

Microbial activities important to effects on crop productivity and nutrient cycling can be altered by agricultural management practices. This study was conducted to determine whether soil microbial populations and their N cycling activities differ between conventional and alternative management practices. Physical, chemical, and microbial soil properties were measured at soil depth intervals of 0 to 7.5, 7.5 to 15, and 15 to 30 cm at a site in southeastern Pennsylvania during the second and fifth years after conversion from a conventional, chemically intensive system to alternative systems utilizing legumes and animal manure as N sources. In the second year after conversion, populations of fungi and bacteria, dehydrogenase activity, and soil respiration in the surface soil layer were greatest with alternative systems planted to red clover (Trifolium pratense L.). Differences in soil biological factors between management systems were related primarily to crop characteristics and, to a lesser extent, to soil physical properties. Levels of microbial populations and activities with conventional management were the same as with alternative management systems when similar crops such as corn (Zea mays L.) or soybean [Glycine max (L.) Merrill] were grown. Soil NO3-N contents, at most sampling depths, were markedly increased by application of fertilizer N or recent plow-down of red clover or hairy vetch (Vicia villosa Roth). The growth of red clover in the second year or hairy vetch in the fifth year was accompanied by significantly increased microbial biomass and potentially mineralizable N (PMN) reserves in the top 30-cm soil layer-these changes being most pronounced in the surface 0- to 7.5-cm layer. Nitrogen deficiency symptoms and lower corn grain yields in a legume/cash grain rotation as compared with conventional management in the second year were associated with lower soil NO3, levels and a greater proportion of N present as weed biomass and belowground microbial biomass. In 1985, management systems comparisons were limited to corn as the main crop; soil NO3 levels during the growing season were inversely related to soil microbial biomass and PMN levels where hairy vetch was overseeded and incorporated as green manure by plowing before corn planting. Under the conditions of this study, the use of chemicals had little effect on microbial populations, their activity, or the cycling of nitrogen. Cropping systems-in particular, the growth of red clover or hairy vetch—profoundly influenced soil microbial biomass levels and soil pools of organic and available NO3-N during the growing season. Competitiveness of alternative management systems employing legumes as? sources for grain crops may depend largely on the grower's ability to synchronize supplies of available soil N with periods of maximum uptake by grain crops.

Railway noise in towns and city centres is one of the environmental problems. Dening the noise level is possible in two ways via in situ measurement or via calculation (prediction). For the comparison of objectively measured values of sound pressure levels from railroads two methods used in the Slovak Republic were chosen Schall 03 and the Czech prediction method. Track number 170: ZvolenVrútky in the town Zvolen was selected as the measurement location of noise exposure. Method Schall 03 overestimates the measurement values by approximately 1 dB and the Czech method by 4 dB. Both prediction methods, in spite of the systematic overestimating, describe the real noise situation very well; the calculated Pearson coecient of correlation with Schall 03 method was 0.94 and with the Czech method 0.90.

Traditionally, exotic hardwoods are used for the production of xylophone or concert marimba. Mainly the Honduran rosewood shows the optimal properties (high density, high modulus of elasticity, speed of sound, hardness, low damping) considering the required acoustic quality of the xylophone. The Honduran rosewood is listed in CITES Appendix II, therefore it is necessary to look for possibilities of its replacement by other wood species. However, the density, hardness and strength properties of the European wood species are rated less than Honduran rosewood. Therefore it is clear that there is a need to search for alternative of exotic wood. Our research indicates that the Honduran rosewood can be replaced by European wood species; however it is necessary to modify their properties. As convenient modication of domestic wood species appear: mechanical modication (densication), thermal modication or a combination of these two methods. Thus we can obtain wood with properties similar to the properties of exotic wood. The study presents the comparison of physical and acoustical characteristics of modied wood of Black locust with the characteristics of the Honduran rosewood. Also, the sound quality of xylophone made from Black locust wood before and after modication was investigated.

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This paper proposes a multi-criteria decision-making model, for the selection and evaluation of the most valuable wooden input-resonant wood. Application of a given model can improve the process of input valuation as well as impact and improve particular economic indicators for the resonant wood manufacturer. We have tried to describe and evaluate the supply chain of resonant wood manufacturing and production of musical instruments. Particular value-added and non-value-added activities have been chosen according to the logical sequence of technology. Then, concrete criteria were specified and their significance weightings. Another important part of our paper is the description of resonant wood, specifications, and demands on log and wood species. There are some important physical and mechanical properties which should be taken into account and evaluated during the production of musical instruments. By the application of this model, a particular enterprise can reach an enhanced tool for the continuous evaluation of the product flowing through the supply chain. Visibility of particular operations and their logical sequence, presented by Petri nets, can lead to easier detection of possible defects in these operations and their origin. So, the main purpose of the paper lies in the suggestion of an objective and quantified managerial tool for the decision making.

When the sound wave touches the material (wall), some fraction reflex the wall, other fraction is absorbed and the rest fraction of the sound wave will go through the wall. So, in every enclosed space we can say about sound absorption, transformation of sound energy into some other energy. Sound absorption coefficient α (-) can be mentioned as criteria for the standard of sound absorption by the material. The article deals with the evaluation of sound absorption in the chosen materials which are utilised in wooden buildings, construction parts of partition walls and ceilings, floors and walls cover. There were used the following materials which are applied in the construction of wood buildings: particleboard (DTD), oriented strand board (OSB), beech plywood (PDP_BK), poplar plywood (PDP_TO), tetra pak recycled board (TETRA K), gypsum fibreboard (Fermacell), cement chipboard (CTD), plasterboard (Rigips) and medium-density fibreboard (MDF). The measurement was performed by the transfer function method in accordance with the standard ISO 10534-2. Under the frequency in the range 200 Hz – 2.0 kHz, the highest values of sound absorption coefficient were measured in CTD, PDP_TO, DTD and OSB within the interval from 0.05 to 0.53. Fermacell and Rigips have the highest values of sound absorption coefficient (0.3 – 0.4) within the frequency from 2.5 kHz to 4 kHz. At the same time, Fermacell, Rigips, but also MDF and TETRA K boards reached the lowest sound absorption (0 – 0.21) within the frequency interval 50 Hz – 2.0 kHz. Sound absorption assessed on the base of NRC coefficient was measured as very low (under 0.2) for all assessed materials, except of CTD. The tested board materials according to the standard ISO 11654 can be included among sound reflective material and little sound absorptive material. The highest level of noise reduction coefficient αNRC was measured at cement chipboard CTD (αNRC = 0.3) which can be included among absorptive materials. The results should be transformed into predictions in room and building acoustics, particularly in the design and projection of partition wall constructions in ultra-low energy buildings but also in the entire interior equipment.

The main aim of the paper is to propose formalised decision-making model for the selection of suitable parts of raw wood for the production of musical instruments and to decrease uncertainty in the purchasing process. It deals with the problem which was never solved before. The paper presents the methodology of input evaluation, considering the principles of sustainable development. We present by means of a supplier selection example and criteria evaluation, that an outranking approach may be very well suited as a decision-making tool for initial purchasing decisions. We have identified this step from the scientific point of view and from the questionnaire sent to musical instrument producers. There were used the following methods: questionnaire, decision tree and statistical methods of questionnaire processing. Our proposed decision tool/methodology could help on both sides of supply chain – as on the side of raw wood supply as on the side of raw wood demand. Based on the results of scientific research we can say that all assessed hypotheses were confirmed and, in the following, it was designed decision-making model by the method of decision tree. We have developed a conceptual model of buyer’s decision-making uncertainty can be reduced by the buyer’s perceptions of supplier trust, supplier commitment, and supplier dependence. Based on data collected from a questionnaire, our study confirms the negative effect of buyers’ trust in the supplier on their uncertainty in purchase decisions. It helps to optimise the identification, specification and evaluation of key factors for a wood as an input into the production of musical instruments. From the economic point of view, our proposals could help to increase value added in the production of wooden musical instruments and at the same time it could decrease possible waste from the undesirable raw wood input.