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The distribution of cadmium, lead and zinc in exchangeable, organic, and 2M HNO3-extractable fractions as well as the effect of heavy metal concentrations on soil microflora was investigated. Six sampling transects were chosen in theLitavkaRiveralluvium in 1999-2001. Concentrations of all metals increased with decreasing distance from the source of contamination. The concentrations of Cd and Zn in exchangeable fraction were higher than in organically bound fraction, a reverse trend was found in Pb speciation. All measured parameters of soil microbial activity were affected by heavy metal concentrations. The decrease in CFU was most significant in the case of oligotrophic bacteria and spore-forming bacteria. Significant inhibition of C-biomass occurred in soils highly contaminated by heavy metals. The Cbiomass:Cox ratio decreased with increasing soil pollution. Generally, the values of enzymatic activities were highest in the soil above the source of contamination and they were decreased as approaching the source of contamination. Our results demonstrate that several parameters of microbial activity could be used as good indicators of increasing concentrations of Cd, Pb, and Zn in soil.

Pea (Pisum sativum L.), sunflower (Helianthus annuus L.) and maize (Zea mays L.) plants were cultivated for 10 days in hydroponics at 1mM and 7mM nitrate or ammonium concentrations at regulated pH 6 and ambient CO2 level. Plant growth, content of total N and both ions in plant tissues, uptake of water and both N ions were evaluated, N uptake related to transpiration mass flow and to diffusion supply was calculated. Pea and sunflower preferred nitrate nutrition while maize plants used both N ions. The content of total N as well as of both N ions in plant tissues increased with N level with some exceptions. The uptake of both N ions related to transpiration mass flow was dependent on transpiration rate and N ion concentration. At a 1mM N concentration the uptake of N ions related to transpiration mass flow was low and reached in maize up to 16 times, in sunflower 11 times and in pea 2-3 times lower values in comparison with diffusion supply. At a 7mM N concentration N uptake in pea plants was totally supplied by transpiration mass flow, in sunflower plants the ratio of N supply related to transpiration mass flow amounted to 50% and in maize plants N supply through diffusion prevailed, amounting to 70-80%. These results explicate N starvation at low N supply that can intensify at elevated CO2 causing decreased stomatal diffusion.

In this four-year study, fruits of Golden Delicious cv. randomly sampled from four different orchards on M 9 were kept at 1 or 2^oC in air storage, and in the course of storing individually assessed for weight, skin colour, skin blush, skin waxiness, flesh firmness, vitamin C content, total acid content, pH value, total sugars, dry matter and calcium content. Changes in some of these fruit quality characteristics during storage are presented and compared with their course during storage both in the cellar and ULO. The maximum storage life of the fruits in the air storage was estimated at 150 days on average. From individual fruit data, correlations between all the observed characteristics at different stages of the storage period were calculated. Fruit weight was positively correlated with dry matter, vitamin C, sugar and acid content, but negatively correlated with flesh firmness and calcium content. Fruits with more skin blush were correlated with higher vitamin C. Flesh firmness was mostly correlated with dry matter content, but negatively correlated with calcium content and pH values. Vitamin C content was positively correlated with total acids, but negatively correlated with pH values, sugar:acid ratio and calcium content. Total acids were negatively correlated with pH values and sugar:acid ratio. At the end of the storage period, the total acid content was also correlated with dry matter content. Total sugars were closely correlated with dry matter content and negatively correlated with calcium content. Calcium content was very closely negatively correlated with dry matter content, and also negatively correlated with the sugar:acid ratio.

Differentiation of forest technologies according to ecosystem properties is a necessary step to achieve sustainable forestry. A forest typological system is considered to be the basic unit of ecosystem differentiation in the Czech Republic. Terrain characteristics, potential water erosion and applicable harvest technology were examined for 44 forest sites in a landscape segment of the Jizerské hory Mts. Forest site was found homogeneous in terms of terrain and technological properties. Edaphic category and groups of forest types as higher classification units and management sets as units of alternative classification showed lower homogeneity insufficient for operational planning.

In the area of southern Poland 33 pine stands growing at the altitudes from 350 to 1,200 m above sea level in the Carpathian and Sudeten Mountains were selected as the object of studies. Thirty-three site chronologies of tree-rings, representing each site were constructed. A decrease in the similarity of dendrochronological signal chronologies occurred with the growing distance between the sites. Correlation and convergence analysis and the Principal Components Analysis permitted the differentiation of two chronology groups: the Western (Sudeten) and the Eastern (Carpathian) ones. On the basis of the site chronologies regional chronologies for the Carpathian and Sudeten Mts. were constructed. The investigated pines from the two regions manifested great sensitivity to winter frost and in summer to the deficiency of heat and water. The chronologies were strongly integrated by the pattern of air temperatures, being differentiated by the pluvial conditions.

The analyses of the activity of cambium and the study of the increment of wood during one growing season of pedunculate oak (Quercus robur L.) under conditions of a floodplain forest is provided. The following parameters were studied: the beginning and end of the cambial activity, differentiation of wood fibres (libriform) and vessels and analysis of the total increment of wood during vegetation in dominant (D), co-dominant (CD) and subdominant (SD) trees in relation to ecological factors of the environment. The course of wood formation corresponds to typical growth curves which are modified by factors of the environment (mean daily temperature, precipitation, soil water supply). The rate of growth is limited by factors of the environment and under the lack of some of them it is reduced resulting in the decrease in the total production of cells. Oak is a species sensitively responding to the period of drought which is particularly manifested in wood increment in subdominant trees. Sufficient supplies of water during spring months accelerate the formation of early wood including differentiation of spring vessels as corroborated by the results. The total formation of wood is dependent not only on the characteristics of the respective growing season but particularly on the social position of trees in the stand.

In the paper, there is described using of the optimization models AGRO-3 SR for modeling food production chains in the Slovak Republic (the modified version of the Czech model AGRO-3) and ALOKA for optimal allocation of the domestic agricultural production computed by AGRO-3 SR into 4 different regions of the SR for simulation of consequences of various types of agrarian policies on the effectiveness of the Slovak agriculture to the medium-term horizon 2005. There are formulated and evaluated 4 scenarios for the model AGRO-3 SR and two alternatives A and B for the model ALOKA relating to all scenarios. Results of simulations have shown that the best result was reached in the scenario 4 by the price liberalization in the whole food chains.

Zinc distribution in the main soil fractions and zinc accumulation in potatoes, maize, wheat and barley after different soil treatments (basic sludge rate, triple sludge rate, NPK, NPK + inorganic Zn) were investigated in a field experiment conducted at five localities of the Czech Republic (Červený Újezd, Hněvčeves, Humpolec, Lukavec, Suchdol) with different soil and climatic conditions. Three soil types were investigated in the experiment: clay-loamy Chernozems, loamy Luvisols, clay-loamy Luvisols and two loamy Cambisols. Sequential analyses provided an overview of soil Zn distribution in the following fractions: exchangeable, Fe-Mn oxide, organic and residual ones. The sludge and inorganic Zn addition supported Zn mobility growth and higher Zn retention in Fe-Mn oxides in all tested soils. The influence of the above-mentioned treatments on higher Zn association with soil organic compounds was not explicitly found. Potatoes, wheat and barley accumulated more Zn after its addition into the soils by sludge and inorganic salt. By contrast, Zn content in maize decreased with higher input of Zn into the soil. The highest Zn concentrations were usually observed in plants grown on both Cambisols.

Rapeseed (Brassica napus L.) is an important alternate oilseed crop in eastern Anatolia, Turkey. No information on plant density for rapeseed is available in this region. Therefore a study was initiated to investigate the effects of spacings between rows and spacings within rows on the yield and agronomic characteristics of two genotypes of spring rapeseed (Tower and Lirawell) in Erzurum, eastern Anatolia, during 1994 and 1995. The effects of spacings between or within rows on the yield and yield components of Tower and Lirawell, two cultivars of Brassica napus L., were studied for 2 years inErzurum,Turkey. Rows were spaced at 15, 30 and45 cm. Spacings within rows were 5, 10 and15 cm. The results of this study suggested that seed yield was significantly affected by spacings between rows but not by spacings within rows, and that rape yields were higher at the narrow (15 cm) row spacing compared to the middle (30 cm) and wider (45 cm) spacings.

The paper is based on a special sampling survey of farms that was conducted under EU PHARE ACE research project P97-8158-R "Micro-economic Analysis of Farm Restructuring in Central and Eastern Europe" in 2000 in one of the NUTS 2 regions of the CR - in the South-East region. The region involves two administrative regions - Vysočina and South Moravian NUTS 3 and consists of subregions with different natural and market conditions (of hilly, lowland and suburban type) representing the conditions of agricultural production in the Czech Republic as a whole. The main results of the survey focused on farms of three different categories are presented: farms as legal entities (separately agricultural production cooperatives, joint stock companies and limited liability companies), officially registered individual farms of different size (formally licensed to business activities) and unregistered individual farms including small farming units - households with self-sustaining agricultural production.

The paper concentrates on analytical findings of the RIAE in the sphere of problems associated with the readiness of Czech agriculture for the EU accession. An analysis of the present situation of Czech agriculture is followed by an assessment of potential impacts of the EU conditions on the economic position of the main agricultural commodities. The predictions are conceived by variants, because the future parameters of the CAP are still under negotiations. The conclusions are oriented on the summary assessment of the readiness of Czech agriculture for the EU accession.

This paper introduces partial results of the research project QC 1140 aimed at the efficiency of enterprises operating in the system of organic farming, especially considering the use of grassland linked with cattle management. Economic evaluation of cattle management in the system of organic farming is compared with conventional enterprises. Economic evaluation applies to dairy cattle and beef cattle. Proposals of the measures will be formed with respect to the results of analysys, which should contribute to the support of organic enterprises and to better satisfaction of the increasing demand for organic food.

We evaluated the need for low temperatures (vernalization) and the photoperiodic reaction of three collections of winter oats (1. Pedarn, Maris Quest, Peniarth; 2. Gerald, Solva, Kymon, Pendragon; 3. Pewi, Silwi, Wiskas) in a comparison with spring oats varieties. All three collections of varieties showed little need for low temperatures, mostly as few as 10-20 days, which does not represent an obligatory need; this influence is only quantitative and constitutes no precondition for a passage of plants into the generative stage. Only in the case of the Maris Quest variety, the need for vernalization approached 30 days. As compared with the reaction of winter barley varieties that had and in some cases still have worse overwintering in the Czech Republic, the length of vernalization is equal. In the photoperiodic experiment, the reaction to a short autumn day turned out to be the critical condition for a possibility of autumn sowing and overwintering; in the case of these varieties, a short day inhibits the development until arrival of winter. We evaluated this reaction according to the length of the induction period. This period was only 10-15 days in the case of the spring oats Český žlutý, 30 days in the case of winter oats Maris Quest, 25 days for Pedarn, 20 days for Peniarth and 21 days for Pendra-gon; the induction period was 14-21 days in the case of varieties Gerald, Kymon and Solva. When compared with figures for winter barley, it had the longer photoperiodic induction period. The evaluated varieties of winter oats do not reach such a degree of a reaction to a short day, which manifests itself in their lower frosthardiness than that of winter barley. We verified that in provoking tests for frosthardiness, and also by lower critical values of temperatures for dying out of 50% of plants, the so-called LT 50.

A morphometric study of Amaranthus cruentus, A. retroflexus and their hybrid, A. × turicensis based on 75 plant samples (750 inflorescences), collected throughout the Olomouc-Holice area (Czech Republic), is presented. Using multivariete methods (including cluster analysis and canonical discriminant analysis), the existence of three groupings of plants was proven. The hybrid exhibited intermediate values of the width and length of female tepals, length of awl-shaped bracts, and seed size when compared with parental species. A germination experiment showed that dark seeds of A. × turicensis as well as dark seeds of A. retroflexus germinate scarcely and independently on the day length while light seeds of A. cruentus germinate promptly and markedly better under a short day regime. The chromosome analysis showed that A. retroflexus, A. cruentus, and A. × turicensis have the same chromosome number 34.

Two methods were developed and tested for the measurement of the mowing machine material feed rate (based on the conditioner power input measured by a torque-meter, and/or on the material change in momentum measured by a curved impact plate). The measurements carried out in the year 2001 proved that a very good linear relationship existed between the conditioner power input, output frequency of the apparatus measuring the impact force by means of the impact plate, and the material feed rate through the mowing machine. The calculated R-Squared values were about 0.95. In the year 2002, the impacts of material and condition (parameters) changes on the mowing machine material feed rate measurement accuracy were measured under laboratory conditions. It was evident from the statistical evaluation that changing crop variety, crop maturity, and intensity of conditioning can have a statistically significant influence on the measurement based on the torque-meter. As concerns the impact plate measurement, it was found that it is not possible on the basis of our measurements to determine statistically the influence of the factors tested.

One of the basic demands for milking machines is to maintain a constant vacuum level if air consumption by milking machine is changed. The author designed a device with reducing valve for vacuum level regulation and a simultaneous vacuum pump control enabling electric power to be reduced. The paper deals with a comparison of the operation of standard control valves with the newly designed device used for vacuum regulation from the viewpoint of dynamic properties. When measuring vacuum stability by applying various regulation methods and a subsequent statistical evaluation of the results obtained it was proven that the function of the newly designed regulating device was comparable with the best reducing valves used so far.

The mycoflora was investigated under the conditions of climax spruce stands in the Krkonoše Mountains in relation to wood decomposition. The areas under observation have been affected more or less by air pollution since the eighties. The average mass of deadwood found on the plots is 124 m³ per ha - the mass of fallen trunks is about 32 m3 per ha, mean value from total average. About 128 species of macrofungi were identified that besides others included 43 species of wood-decaying fungi. Also 54 mycorrhizal species were identified. Among the mycorrhizal fungi about 10 species were dominant, such as Laccaria laccata (Scop.: Fr.) Cooke, Lactarius helvus Fr., Lactarius mitissimus Fr., Lactarius rufus (Scop.) Fr., Russula emetica (Schaeff.: Fr.) Pers. and Russula ochroleuca Pers. etc. Concerning the volume of decomposed wood on monitored plots in climax spruce stands, the prevalent wood-decaying fungi are brown rot fungi. The proportion of brown rot fungi in wood decomposition is 60-95% of deadwood mass on the plots of climax spruce stands. A dominant species is Fomitopsis pinicola (Sw.: Fr.) P. Karst. causing the brown rot. Concerning the group of white rot fungi, the most important is Stereum sanguinolentum (Alb. & Schw.: Fr.) Fr., participating by 17% in wood decomposition on plots damaged by deer.

During the years of transition to market economy, a variety of farming types has evolved in Slovakia. Corporate farming is still pursued on about 80 per cent of the total agricultural land area, but a gradual increase of individual farms can be observed. A large portion of the registered individual farms is producing both for the market and for the self-supply of households, but the importance of specialised commercial farms has been growing during the recent years. Their share in the total number of registered individual farms can be estimated as 25 per cent and they specialise as a rule on cash crop products. The average production area is 130 hectares, but income differentiation is wide-ranging within this group of farms. The lowest income strata (which represent about 50 per cent of these farms) receive eight times less income, than the highest one - represented by less than 2 per cent of cases.

The aim of this presentation is to introduce partial results of this research project aimed to the efficiency of businesses working with the organic systems. The proposal of mesures will be formed with the respect of results of analysis to support organic businesses, to increase organic land area corresponding with the progress in the EU and therefore to help to satisfy increasing demand for organic food, last but not least also to prove, that organic agriculture is truly functioning part of multifunctional agriculture.

This paper is focused on: (1) Managerial accounting analysis as a source of information provided for product costs management (mainly from the point of view of exploitation of budgeting and costing in selected companies in agriculture), (2) Possibilities of integration and information processing for product cost management, provided by managerial accounting in the framework of managerial information system of the company.

The effect of droplet spectra on efficiency of contact and systemic herbicides was evaluated. As a model components were used: mixture of clethodim 240 g/l + surfactant (90% raps fluid, 10% polyetoxyl esters); bentazon 600 g/l and bentazon 480 g/l + Wettol LF 150 g/l. The effect of droplet spectra on Elytrigia repens (L.) Desv. was evaluated using systemic herbicide (clethodim 240 g/l + surfactant). No significant differences of the efficiency were observed between different droplet sizes at the treatments of mixture of clethodim + adjuvant between very different droplet size ranging from VMD = 193 µm to VMD = 929 µm. The effect of droplet spectra on Chenopodium album L. and Galium aparine L. was evaluated using contact herbicides (bentazon 600 g/l and bentazon 480 g/l + Wettol LF 150 g/l). Six droplet spectra, ranging from VMD = 183 µm to VMD = 911 µm, were used. The efficiency significantly increased with smaller droplet sizes. The worst results were achieved by droplet spectra of 586 µm and 911 µm for both bentazon 600 g/l and bentazon 480 g/l + Wettol LF 150 g/l. Effect of droplet spectra is more pronounced in contact compounds. Translocation of systemic compounds may be the main mechanism that nullifies the effect of the droplets size and lower leaf coverage.

Root growth inhibition and loss of cell viability in barley root cells were induced by Al during germination of barley caryopses on filter paper moistened with 2mM AlCl3. The inhibition of root growth as well as loss of cell viability started on the third day of germination. This time was also needed for induction of Al-induced changes in the composition of cell wall proteins. The accumulation of three salt-extractable polypeptides with relative molecular mass 14, 27, and 29 kDa started 72 h after the beginning of germination of barley caryopses on Al containing filter paper. However, the inhibition of developmentally regulated deposition of three (18, 23 and 28 kDa) salt-extractable CW polypeptides was observed at the same time. The pattern of detergent-extractable CW proteins was not influenced by Al regardless of the duration of Al treatment.

The yield potential, quality and level of resistance to powdery mildew (Erysiphe pisi DC.) of afila smooth seeded pea (Pisum sativum L.) were tested in the field trials. The cultivars and breeding lines Mozart, Consort-R, AGT-01, Cebeco 1171 and AGT-GH surpassed the control cv. Gotik in the yields of dry seed, in contrast the dry seed yields of Highlight, AGT-KR, Melfort and LU 390-R2 were about 12-27% lower than that of the control. The low seed yield was caused by virus infections (PEMV, BYMV), root diseases (Pythium, Fusarium), and a low level of thousand seeds weight (TSW). Material crossing with donors possessing high yield potential, a higher TSW, and a higher tolerance to root diseases had a positive effect on the dry seed yield. The main objective of the resistant pea breeding programme is afila smooth seeded pea resistant to powdery mildew, with a high tolerance to viruses, root diseases, and lodging, with the stem length of 60 to75 cm, and with high yield potential.

In birch (Betula pendula Roth) stands of the Děčín sandstone uplands (northern Bohemia) 55 species of leafhoppers were captured using photoeclectors, ground traps and shaking down onto sheets (23,855 specimens of larvae and imagoes). The dominant representatives of the grass and herb undergrowth in birch stands are Jassargus allobrogicus, Anoscopus flavostriatus, Neophilaenus lineatus, Hyledelphax elegantula, Diplocolenus bohemani, Streptanus brevipennis, Macustus grisescens, Planaphrodes bifasciata and Cercopis vulnerata. A heavy abundance of the dominant Oncopis flavicollis and the less abundant O. tristis, weakens birch growth due to the leaf-sucking activities of the insects.

The present study documents the effects of green alder [Alnus alnobetula (Ehrh.) C. Koch] on the uppermost forest soil layers in mountain areas, respectively in the summit part of the Jizerské hory Mts. Pedochemical characteristics of holorganic horizons in stands of this species, established in 1992 on a clear-cut caused by air pollution, were compared to the status of soils in stands of bog pine (Pinus rotundata Link.). Extreme site conditions and young age of both stand types resulted in low effects on the humus forms in the first decade. Despite of this, enrichment in total nitrogen content and tendency to acidification due to nitrate leaching were obvious and statistically significant in green alder stands.

A traditional approach to problems of the opening-up of forests has been based primarily on technical and economic aspects. It results particularly from the ground configuration and calculations of minimum costs for logging and transport operations. Optimum density of main forest roads is determined by a minimum value of the summary curve of costs of forest road construction and timber skidding. A new conception from the aspect of integrated forest management taking into account forest functions is based on a standard approach when technical and economic aspects are complemented by the particular functions of the forest. Thus, the technical and economic approach is changed to a technical-economic-environmental conception that will contribute to a reduction in negative effects of the construction of forest road network on the environment.

Decreasing numbers of tourists to the Czech Republic point at a weakening competitive position of Czech destinations during the most recent years. For many communities, tourism may be a short-lived economic dream when understanding of tourists´ perceptions and travel motives is lacking. The two objectives pursued in this study are 1) an identification of the positions of competing destinations and 2) an a-posteriori segmentation with psychographic variables. Market segmentation becomes the crucial factor in the strategic design process of target marketing. Like many other markets, tourism markets do not respond homogeneously to marketing activities. Subdividing visitors into useful groups may provide a basis for competitive advantage. Our study establishes taxonomy of visitors to Southern Moravia. The study tries to overcome well-known insufficiencies of single segmentation approaches by exploiting the advantage of the multivariate nature of combined push factors, pull factors, and other factors of more restrictive nature (i.e. time and money). The segmentation task employs multivariate data analysis techniques such as factor analysis, cluster analysis and multi-dimensional scaling. Recent research on the European Vacation Style Typology is incorporated.

This article is divided into four parts; the first is concerned with the methodology of evaluation of the type of technical development and its objectives. Another part will evaluate the type of technical development in the national economy as a whole in the period 1995-1999. The main indicators are fund efficiency, productivity of labour and the technical specifications of work. The third part of the contribution will deal with an evaluation of these indicators in the selected sector of the economy, namely in the farms which are obliged to make public their income statements in the business bulletin. The last part, considered from the perspective of the type of technical development will be a farm sample, divided according to size into two groups - production and marginal area. This sample will be considered for the years 1997-2000. Finally a total evaluation of the present development of single monitored groups and an inter group comparison will be carried out.