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Results 5371 to 5400 of 5824:

The overview of methodology aspects in product economics in Slovak agriculture

J. Varoščák

Agric. Econ. - Czech, 2004, 50(11):524-528 | DOI: 10.17221/5243-AGRICECON

The accession to the European Union has brought a number of issues that the new member states have to deal with, namely to use the rules and procedures applicable in the EU. These include the transition from the enterprise towards the product-oriented economy in the agricultural production enterprises. The article describes the aspects of methodology regarding this issue within the framework of the Slovak agriculture. The article emphasizes that the product economics allows to define three levels of profit, namely: market, product and enterprise profit. This issue will be illustrated on the example of a Slovak agricultural enterprise, in terms of its planned calculated generation of profit.

Winter frost resistance of Hayward and Matua kiwifruit cultivars

M. Burak, H. Samanci, M. Büyükyilmaz

Hort. Sci. (Prague), 2004, 31(1):27-30 | DOI: 10.17221/3788-HORTSCI

This study was carried out in Atatürk Central Horticultural Research Institute at Yalova in 1996 and 1997 in order to determine the frost resistance ability of fruit buds of Hayward and Matua cultivars by artificial freezing tests during winter months. Twig samples for artificial freezing tests were taken one week after defoliation, and at three-week intervals throughout the winter. The buds were exposed to temperatures of -10°C, -13°C and -15°C for 2, 4 and 6 hours. Then they were planted in a greenhouse for survival tests. It was found that -13°C and -15°C were very harmful temperatures for both cultivars even for the duration of 2 hours at -150C. On the other hand, both cultivars could resist to -10°C for the duration of 6 hours. In general, Hayward is more sensitive to frost than Matua. Both cultivars showed higher resistance in February. As a result, Hayward and Matua cultivars could be grown safely in areas with as low temperatures as -10°C in winter months.

Application of logistics in woodworking industry

J. Štůsek

J. For. Sci., 2004, 50(3):142-148 | DOI: 10.17221/4609-JFS

The paper is focused on logistics. The importance of the logistic chain management is emphasized as it becomes a crucial competitive success factor. The total corporate costs and customer service quality are dependent on the structure and communication within this chain. Using a concrete example, several results of the establishment of the logistic approach in the woodworking industry are mentioned in the paper. It has to be emphasized that the application of the logistic principles in the industry has its own specificities arising mainly from the biological character of processes providing and manufacturing the basis resource. A solution of the supply - purchase chain is provided on the basis of an example of the company Dřevovýroba.

Slovak agriculture and the integration into the EU

G. Blaas

Agric. Econ. - Czech, 2004, 50(3):100-104 | DOI: 10.17221/5174-AGRICECON

The paper is briefly outlining the expected changes in the economic and financial pre-conditions for Slovak farming during the period after the country's accession to the EU. The starting point of authors reasoning is the current piece of knowledge, saying that the economic performance of individual farms is widely differentiated and the ability of individual farms to meet the future challenges and to use the opportunities is very unevenly distributed among them. Also the competitiveness if a particular agricultural commodity varies. Despite of expectations concerning the price development after accession, not all commodities will be competitive on the single market. The economic situation of farms will considerably benefit from direct payments. Nevertheless, the fact that the Slovak government opted for the Single Area payment Scheme will have some adverse effects on possible gains from payments in productive regions and in farms with high output performance. In order to mitigate these redistribution effects the author is proposing to implement a different scheme of allocation of national top-up is to direct payments. In the final part of his paper the author gives a comprehensive review on payments aimed to promote rural development and payments from the Guidance section of the EAGGF targeted at enhancement of farm re-structuring.

Forestry students and workers and their attitudes towards the environment

M. Pernica

J. For. Sci., 2004, 50(1):47-54 | DOI: 10.17221/4600-JFS

In any activity, thus at work as well, there is an influence of the environment on a human being. This environment, to which every worker has his own individual relationship, becomes a part and background of the worker's life. The realization of these interactions and relationships markedly affects achieved working results. The ecologically harmless technologies will not be used in forestry considerately towards the environment if forestry workers do not change their negative attitudes to their environment. In this project we tried to map out environmental knowledge of forestry workers.

Larch crown diseases in Trentino and South Tyrol

G. Maresi, P. Capretti, P. Ambrosi, S. Minerbi

J. For. Sci., 2004, 50(7):313-318 | DOI: 10.17221/4628-JFS

Various attacks of pathogenic fungi on the larch crown were observed in Trentino/South Tyrol, Italy, over the past few years. In 1999, severe defoliation was caused by Mycosphaerella laricina, a rarely investigated pathogen, whose action was enhanced by high temperatures and humidity in August. In July 2000, larch woods showed crown yellowing due to Meria laricis. Lower temperatures and heavy precipitation were probably the predisposing factors in this case. Hypodermella laricis was observed in 2002 as a localised attack, while Lachnellula wilkommii is commonly recorded. The impact of these diseases and the environmental factors involved in their occurrence are discussed in this paper.

Technology and economy of energy crops

Z. Abrham, M. Kovářová, T. Kuncová

Res. Agr. Eng., 2004, 50(4):123-129 | DOI: 10.17221/4938-RAE

The cost modelling for growing and harvest of selected energy crops and further costs for recommended forms of energy crops processing to biofuels was conducted. Importance and effect of subsidies on resulted costs for biofuels production was assessed. The result are then total costs per unit of fuel weight which range from 469 to 1,806 CZK/t for biofuels processed to form of chopped material or pressed bales and from 881 to 2,466 CZK/t for briquettes and pellets. The result costs per energy unit in biofuel have ranged from 59 to 121 CZK/GJ. On basis of economical data is evaluated the biofuels competitive power in comparison with main competitive fuels on market. The energy crops specific costs without subsidies are higher thus their position on market will be complicated, lower specific costs can be expected only when residual biomass would be utilised (grain straw). The competitive power of the energy crops will be much better as the subsidies are utilised in 2004 and total specific costs for chopped material are from 82 to 142% of brown coal price, 95-137% for briquettes in comparison with the brown coal briquettes. The energy utilisation if winter wheat and sorghum is economically unsuitable.

How to approach the development of enterprise information system

I. Vrana

Agric. Econ. - Czech, 2004, 50(1):41-46 | DOI: 10.17221/5165-AGRICECON

Nowadays, many enterprises face the problem of implementing their enterprise information system in order to keep pace with their competition. It holds generally for all types of enterprises, as e.g. manufacturing, agricultural, trading, financial, transportation, educational, etc. This paper deals with the basic rules for building an information system of the enterprise, particularly of medium or large ones. The attention is focussed at the problems each enterprise must address before starting an IS project. These are mainly the enterprise information policy planning, project feasibility and forms of its management.

20th Biennial Conference of the European Society for Rural Sociology

E. Kučerová

Agric. Econ. - Czech, 2004, 50(4):185-188 | DOI: 10.17221/5187-AGRICECON

The influence of state subsidies on the development of organic agriculture in the Czech Republic and in the EU

J. Jánský, I. Živělová, P. Novák

Agric. Econ. - Czech, 2004, 50(9):394-399 | DOI: 10.17221/5224-AGRICECON

The paper presents selected results of the research project NAZV QF 3278 focused on objectification of supply and demand development for organic products. The evaluation of state subsidies' influence on the development of organic agriculture in the Czech Republic and in selected countries of the EU is also included.

Efficacy of biofungicides Supresivit and Polyversum against Phytophthora root pathogens on European chestnut (Castanea sativa Mill.)

G. Juhásová, S. Bernadovičová

Hort. Sci. (Prague), 2004, 31(3):109-114 | DOI: 10.17221/3802-HORTSCI

The effect of two commercially produced biopreparations on the originators of chestnut ink disease in Slovakia - soil fungi Phytophthora cambivora and Phytophthora cinnamomi was tested in laboratory conditions. Investigations of interrelations between Trichoderma harzianum (Pythium oligandrum) and isolates of Phytophthora sp. obtained from infected tissues of Castanea sativa Mill. proved more important inhibitive effects for Pythium oligandrum (biopreparation Polyversum); efficiency 25.3% (Ph. cambivora) and 26.2% (Ph. cinnamomi). Biopreparation Supresivit (Trichoderma harzianum) reached the efficiency 9.1% for Ph. cambivora isolates and 9.2% for Ph. cinnamomi isolates. Significant effect of the used bioformulas for inhibition of mycelial growth of both Phytophthora sp. and significant difference in the efficacy of two different bioformulas were confirmed statistically.

A new concept in sustainable forest management - the need for forest ecosystem and landscape research

J. Kulhavý

J. For. Sci., 2004, 50(11):520-525 | DOI: 10.17221/4650-JFS

The greatest advance in ecosystem research was made in the last century. The development and acceptance of forest ecology by foresters occurred because it provided a means for recognizing, understanding, classifying and mapping the natural variation of forests. Forest ecology involved studies at the individual, population, community, and ecosystem levels but such studies always needed to involve the ecosystem concept. Today, the new concept of "ecosystem and landscape forestry" integrating ecological and socio-economic research has been developed on the basis of EU COST Action E-25 European Network for a Long-term Forest Ecosystem and Landscape Research Programme. An analysis has been carried out of the present situation in forest research in the Czech Republic. The need for forest ecosystem and landscape research is obvious.

Barley response to the soil reserve of sulphur and ammonium sulphate in short-term experiments under controlled conditions of cultivation

J. Matula

Plant Soil Environ., 2004, 50(6):235-242 | DOI: 10.17221/4027-PSE

The objective of the paper was to determine an appropriate concentration of available sulphur in soil for the initial growth of plants. Based on previous researches two methods of soil extraction were used to acquire information on the soil reserve: water extraction (H2O 1:5, w/v) and extraction in 0.5M ammonium acetate with addition of NH4F (KVK-UF soil test). Spring barley was used as a test crop to determine the soil reserve of sulphur and its response to sulphur addition to the soil. A collection of 48 samples of topsoil from agriculturally important localities in the CR was made up for this purpose and the parameters of the nutrient status of the soil were remarkably different. A set of soils was used to establish short-time vegetation experiments in a plant growth chamber according to the scheme: A) control - without sulphur application and B) response variant with application of 30 mg S/kg of soil in the form of (NH)4SO4; nitrogen in variant A was adjusted by application of NH4Cl. Index of nutrient efficiency (IE = Y/N where Y = yield and N = nutrient concentration in the plant) and boundary lines of the point field were used to evaluate the efficiency of barley nutrition with sulphur. The efficient soil reserve of sulphur for the soil test H2O (1:5) when the ICP analytical technique was used was indicated in the range of 8-11 mg S/kg; 6-10 mg S/kg for sulphate detection on a SKALAR analyser. The efficient utilisation of sulphur by barley plants for the KVK-UF soil test was in the range of 7-12 mg S/kg. The conversion of the KVK-UF S-test to the index of soil reserve of sulphur by adding up a variable portion of the CEC value to the value of sulphur determined by the soil test (0.0167CEC + 9.1667) improved the closeness of the relationship between soil and plant.

Economic strength of Slovakia's regions

S. Buchta

Agric. Econ. - Czech, 2004, 50(4):139-144 | DOI: 10.17221/5181-AGRICECON

The article deals with the identification and categorisation of economic power of Slovak regions on the base of collecting of unemployment support payment from the employers, employees, and natural persons entrepreneurs into the employment fund. The analysis shows that during the last years, the number of rich regions has decreased and there rises the number of counties which have to be supported by the division of means from the rich counties. The article consequently categorises the development of economically strong and weak counties of Slovakia in the years 1999-2002 and marks the causes of regional polarisation of Slovakia, lying in its economic and structural difficulties. Alongside increasing the regional polarisation in the rate of unemployment, there continues to rise the re-distribution of funds for labour-market policy from the economically stronger regions to the economically weaker regions, which are reliant on socio-spatial solidarity. The course of economic transformation up to date has had significantly different regional impacts and creates unequal chances for people as well as businesses in the afflicted areas.

The comparison of natural and value indicators of cereals in the Slovak Republic in accession period to European Union

D. Šimo, N. Kulková

Agric. Econ. - Czech, 2004, 50(8):336-341 | DOI: 10.17221/5212-AGRICECON

Cereals have a significant position in land farming in Slovakia. Important commodities are wheat, barley and maize. In the years 1999-2000, a research showed that Slovakia's natural production was lagging behind the developed countries of the EU. Extraordinary low yields were recorded in the economic year 2000/2001 due to drought during the vegetation period. In this paper, there are analyzed the production prices, costs, cereals efficiency and profitability costs. We have also calculated the break-even point in yields, in costs and in production prices of cereals. In addition, we have done some suggestions and recommendations on how to analyze the results.

Importance of objective and formal adequacy for the indicators of enterprise financial health

F. Střeleček, R. Zdeněk

Agric. Econ. - Czech, 2004, 50(12):543-551 | DOI: 10.17221/5246-AGRICECON

The evaluation of financial health of an enterprise becomes very important in Czech businesses. Among other factors, it is so because it is viewed as a precondition for being eligible for some of the EU structural funds. Models of enterprise financial health were created mainly on the basis of objective evaluation of indicators and discrimination analysis for prosperous and bankrupting enterprises. Little attention was paid to the influence of particular indicators on the total value of enterprise financial health. Using the principles of objective and formal adequacy of the indicators, as well as their standardisation, and the methods of multicriterial evaluation together with the determination of particular indicators independence can improve the creation of financial health indicators and facilitate a higher rate of its objectiveness.

To the distribution of PPV-M strain in selected orchards of apricots and peaches in the Czech Republic

J. Polák

Hort. Sci. (Prague), 2004, 31(2):44-46 | DOI: 10.17221/3791-HORTSCI

The presence and distribution of PPV-M strain of Plum pox virus were investigated in selected orchards of apricots and peaches in the Czech Republic. PPV-M was found to be distributed in apricot and peach orchards planted with nursery material imported from abroad. The presence of PPV-M was not proved in orchards planted with trees from local nurseries. The absence of PPV-M in a majority of spontaneous PPV hosts was proved previously. PPV-M strain appears to have been introduced recently.

The ground beetles (Coleoptera: Carabidae) of forest altitudinal zones of the eastern part of the Krušné hory Mts.

E. Kula, L. Purchart

J. For. Sci., 2004, 50(10):456-463 | DOI: 10.17221/4641-JFS

By means of Sörensen's index and Renkonen's number, the differences in species composition and abundance of the ground beetles (Carabidae) were specified in 5 forest altitudinal zones (3rd, 5th-8th) and also the faunal similarity in the linking-up forest altitudinal zones. The entry of some species (Carabus coriaceus, Carabus violaceus, Pterostichus niger and Pterostichus oblongopunctatus) into higher altitudes was much more marked than is mentioned in hitherto published information. The objective of the present study was to explore the potential use of the ground beetles as an ancillary component of the geobiocoenological typological system.

Methodical approach to evaluation of financial health of agricultural enterprises in relation to the Sector Operational Program

E. Rosochatecká, H. Řezbová

Agric. Econ. - Czech, 2004, 50(3):110-115 | DOI: 10.17221/5176-AGRICECON

The contribution deals with the analysis of methodological approaches to the general evaluation of enterprise results. It is concerned mainly about the methodology of evaluation of financial health of enterprises in the frame of the program SAPARD and further about the possible outline of methodology in the frame of the Sector Operational Plan for agriculture and the Payment Agency. This contribution was prepared in frame of solution of the Institutional Research Intention MSM 411100013.

Firm condition of chosen agricultural enterprises in mountain and sub-mountain areas in South Bohemia

I. Faltová Leitmanová, V. Krutina

Agric. Econ. - Czech, 2004, 50(6):266-270 | DOI: 10.17221/5201-AGRICECON

The economic evaluation of agricultural enterprises in mountain and sub-mountain areas in South Bohemia results from a financial analysis. Financial ratios enable to identify and measure the state and development of individual economic aspects of these enterprises and their synthesis through solvency model makes financial health possible to be elicited.

Economic performance of the Slovak food industry

S. Belešová

Agric. Econ. - Czech, 2004, 50(11):495-501 | DOI: 10.17221/5239-AGRICECON

The requirements for compliance with the manufacturing and quality standards and the related investments in the hygienic and structural upgrading of establishments before Slovakia's accession to the European Union meant that the Slovak food processors had to intensify their effort, revise their objectives (where necessary) and increase the volume of investments, particularly during 2003. Many entrepreneurs, particularly in the animal production, decided to go out of business, mainly because the continued operation of obsolete slaughterhouses would require considerable investment effort; at the end of the day, some meat producers closed their slaughter operations and focused on specialised meat processing. Compared with the year before, the profit of food processors declined by 23%. This was due to the faster decline in revenues than expenses, increased cost of revenues, and the reduced output. Although profitable companies still prevailed, the percentage of loss-making companies increased in comparison with the previous year. The starch industry, sugar industry and the confectionery (including coffee substitutes) industry were some of the sectors where all operators were profitable.

Notes to distribution and seasonal activity of spruce diprionids (Hymenoptera: Diprionidae) in the eastern part of the Czech Republic

J. Holuša, L. Roller

J. For. Sci., 2004, 50(12):579-585 | DOI: 10.17221/4660-JFS

A study of diprionids associated with spruce was done at 31 sites of the eastern part of the Czech Republic in 1988-2003. In total 45 specimens belonging to Gilpinia abieticola (6 specimens), G. hercyniae (3) and G. polytoma (36) were collected using Malaise traps, emergency traps, bark-beetle pheromone baited traps or sweeping. The spruce diprionids were recorded in 30% of the studied sites only. G. polytoma was the most abundant and it is probably bivoltine with adult activity from April to August. The results of emergence trap-monitoring in Paskovský les indicate that this species is in latency.

Performance and gene effects for wheat yield under inoculation of arbuscular mycorrhiza fungi and Azotobacter chroococcum

R. Singh, R.K. Behl, K.P. Singh, P. Jain, N. Narula

Plant Soil Environ., 2004, 50(9):409-415 | DOI: 10.17221/4052-PSE

The present investigation was conducted to know the impact of bio-inoculants in low input field conditions on the magnitude and direction of gene effects and mean performance of some morphological and productivity traits in three wheat cultivars WH 147 (medium mineral input), WH 533 (drought tolerant), Raj 3077 (drought tolerant) and six generations namely P1, P2, F1, F2, BC1 and BC2 of three crosses i.e. WH 147 × WH 533, WH 533 × Raj 3077 and WH 147 × Raj 3077. The experiment was conducted in randomised block design with three replications and three treatments i.e. control (C, without inoculation), inoculation with arbuscular mycorrhiza fungi (AMF, Glomus fasciculatum), and AMF + Azotobacter chroococcum (Azc). Mineral fertilizer (80 kg N/ha + 40 kg P/ha + 18 kg ZnSO4/ha) was applied in all the three treatments. The application of bio-inoculants, AMF and AMF + Azc had a positive effect on plant height, peduncle length, grain yield, biological yield and harvest index in various populations of all the crosses. However, in some of the generations the impact of bio-inoculants was insignificant. The joint scaling test revealed that additive-dominance gene effects were mainly operative in governing expression of peduncle length, tillers per plant, plant height, grains/spike, grain yield and all traits except days to flowering and harvest index in crosses WH 147 × WH 533 and WH 533 × Raj 3077. The application of bioinoculants influenced gene effects for days to flowering, days to maturity, flag leaf area, spike length, grains/spike, 1000 grain weight and harvest index where complex genetic interactions were changed to simple additive-dominance gene effects in the cross WH 147 × Raj 3077. Likewise, additive-dominance gene effects were altered and digenic interactions exhibited for days to maturity, flag leaf area in WH 147 × WH 533 and days to flowering, plant height, flag leaf area in WH 533 × Raj 3077. Flag leaf area and plant height were governed by additive gene effects while for days to maturity and 1000-grain weight both additive and dominance gene effect were important. Duplicate epistasis was important in all the three crosses for days to flowering and harvest index and in the cross WH 147 × Raj 3077 for grain weight grains per spike and flag leaf area.

Influence of heat treatment on mechanical properties of steel

R. Chotěborský, M. Brožek

Res. Agr. Eng., 2004, 50(4):152-155 | DOI: 10.17221/4942-RAE

This article concerns an influence of heat treatment on strength and toughness of steel. The partial results of tests on steel 12 042 are presented.

Exploring successes and failures of the CEEC in the context of the EU accession. The milk and beef sectors in the Czech Republic and Poland

M. Bavorova, H. Hockmann, A. Pieniadz

Agric. Econ. - Czech, 2004, 50(5):189-198 | DOI: 10.17221/5188-AGRICECON

The paper reviews experiences from the accession process of Poland and the Czech Republic, two countries with different accession conditions regarding the agri-food sector. The paper has two main aims. First is to discuss the scope of action in the EU and in the acceding countries from a game theoretical view. The second aim is to identify the reasons for successfully providing beneficial accession criteria. Investigating two selected agricultural sectors does this: milk and beef production. Our overall argument is that the actions, which nations and interest groups have undertaken with regard to the EU accession and future policy direction are, at least partially, a function of different external restrictions and internal national patterns; i.e., the relevance and structure of agriculture and the bargaining power of interest groups.

Czech wine-production industry and recent movement forces

P. Žufan

Agric. Econ. - Czech, 2004, 50(9):400-404 | DOI: 10.17221/5225-AGRICECON

The paper focuses on identification of the current key movement forces in wine-production industry in the Czech Republic, and its goal is to analyse these key influences, and to identify the most important ones (long term industry growth-rate, technological changes, regulation influences and changes of government policy, and changes of societal priorities and life style). Based on the identified key factors influencing future development and changes in this industry, recommendations for firms are formulated.

Effects of pruning on heartwood formation in Scots pine trees

B. Bergström, R. Gref, A. Ericsson

J. For. Sci., 2004, 50(1):11-16 | DOI: 10.17221/4595-JFS

The object of this study was to investigate the effect of pruning on heartwood formation in mature Scots pine (Pinus sylvestris L.) trees. Fifty trees were treated by three different intensive pruning regimes: 42, 60 and 70 percentage of defoliation. After five growing seasons numbers of growth rings were counted and the width and the area of sapwood and heartwood were calculated. The results did not show any proportional increase or decrease in the heartwood area or in the number of growth rings in heartwood associated with the pruning. A statistically significant negative effect of pruning was found on the width of the five most recently formed sapwood growth rings. This decreased growth rate did not influence the ratio of sapwood and heartwood. However, it cannot be excluded that the proportion of heartwood may increase during a longer period. It is concluded that pruning is not a practicable silvicultural method for regulating heartwood formation in mature Scots pine trees.

Changes in cold hardiness of silver fir and larch bare-rooted seedlings during autumn and spring

M. Sarvaš

J. For. Sci., 2004, 50(5):237-242 | DOI: 10.17221/4620-JFS

The objective of this study was to obtain information about changes in cold hardiness of larch and silver fir seedlings during autumn and spring by help of measurements of electrolyte leakage from shoots (SEL) and root system (REL). The values of electrolyte leakage from the untreated (control) root system of silver fir decreased during autumn (from 28% on September 25 to 24% on November 27). Minimum values were reached on March 26. A decrease in electrolyte leakage was found for silver fir shoots (SEL) (the maximum was detected on October 2 - 12% and minimum on November 27 - 7%). Contrary to REL, SEL increased in March. The rate of electrolyte leakage from treated (after artificial frost) roots and shoots decreased during autumn (REL and SEL minimum on November 27). The change in the rate of electrolyte leakage from untreated larch roots was similar to that from silver fir roots during autumn. The values continually decreased from 26% (on September 25) to 12% (on November 27). The course of electrolyte leakage from the treated root system was similar for both species. The differences between electrolyte leakage from larch shoots (treated und untreated ones) were statistically significant, but without any clear tendency during autumn.

Sustainable management of mountain forests in the Czech Republic

S. Vacek, V. Balcar

J. For. Sci., 2004, 50(11):526-532 | DOI: 10.17221/4651-JFS

Forest management in the Czech Republic (CR) was not shaped in the environment of natural forests but in the territory that was influenced by unregulated felling and animal grazing for a long time. Hence the fear for sustainable and balanced benefits from forests endangered by long-term uncontrolled exploitation was legitimate. Almost after three centuries of application of the sustainability principle, forests are considered not only as a source of renewable wood raw material but also as a tool of the environment formation. Mountain forests are an important landscape component of this country. They are an object of specific importance from the aspect of natural environment conservation, stabilization of natural processes and general landscape homeostasis. In addition, they fulfil a number of production and non-production functions. Cardinal elements of sustainable forest management in the CR conditions are as follows: management of the forest as an ecosystem, i.e. transition from exclusive care of forest tree species and their stands to care of the whole forest ecosystems; restructuring (conversion, reconstruction) of damaged and declining forests; optimum (species, genetic, spatial, age) structure of forest ecosystems differentiated according to site conditions and management targets; differentiated transition from general management to group or individual methods; utilization and support of spontaneous processes such as natural regeneration, competition and other principles of self-regulation. The above cardinal elements of sustainable forest management are applicable to forests of the CR in general, but their importance considerably increases in mountain forests where many species survive on the margin of subsistence. Moreover, mountain forests of CR have been heavily destroyed by anthropogenic factors, especially air-pollution ecological stresses, during the last three or four decades.

Adsorption of copper, cadmium and silver from aqueous solutions onto natural carbonaceous materials

P. Hanzlík, J. Jehlička, Z. Weishauptová, O. Šebek

Plant Soil Environ., 2004, 50(6):257-264 | DOI: 10.17221/4030-PSE

Twelve carbonaceous materials were investigated for adsorption of Cd, Cu and Ag from water solutions. Before the adsorption experiments the chemical and structural characterization of all materials were made. The batch adsorption experiment was used. The kinetic of the adsorption process was very fast for the first five hours but very slow for approximately the next 65 hours. Nevertheless the maximum amount of metal removed was achieved during the first stage of about five hours. Biological materials (milled wood, bark, cork) exhibited a very low affinity for adsorption of metals. The best results were obtained for materials in an intermediate degree of carbonisation with a high content of oxygen rich functional groups. Although the highly carbonised materials exhibited low ability to adsorb copper or cadmium, their capacity to bind silver was very high.

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