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Results 1651 to 1680 of 1934:

The influence of tillage on selected biological parameters

O. Mikanová, M. Javůrek, M. Vach, A. Markupová

Plant Soil Environ., 2006, 52(6):271-274 | DOI: 10.17221/3440-PSE

The influence of tillage (conventional and non-tillage) on selected soil microbial properties was studied. The experiment focused on tillage that was launched in Prague-Ruzyne in 1997. The experiment included the following variants: conventional tillage, protective tillage (without post harvest residues), protective tillage (with residue biomass - mulch), protective tillage (covered by pea crop residues for winter wheat, with fore crop). In the field experiment there were tested: enzymatic activities (activity of urease, dehydrogenase, arylsulfatase and invertase) and microbial biomass. The microbial biomass and soil microbial processes were affected by tillage. Our results show the positive influence of protection tillage on selected biological parameters, especially in variants where soil was supplied with organic matter.

Possibilities of using rooted cuttings of European beech (Fagus sylvatica L.) for stabilisation of forest ecosystems

A. Jurásek

J. For. Sci., 2007, 53(11):498-504 | DOI: 10.17221/2021-JFS

Vegetative propagation of forest tree species is of great importance not only for breeding programmes but also for the conservation of valuable populations of tree species. Important is also a possibility of improving the genetic quality of established stands. Beech is a tree species that can substantially increase the stability of forest ecosystems. Minimal information is available about the ontogenesis of rooted cuttings of beech in forest stands for the time being. In our experiments that were gradually established since 1993 we acquired the first significant results of the evaluation of health status, phenological phenomena and growth of these plants. Our findings indicate that it is possible to use rooted cuttings as an element stabilising man-made forest stands including the transferred genetic quality. The evaluation of the 2nd generation rooted cuttings of beech also provided positive results.

Yield and yield components responses of old and new soybean cultivars to source-sink manipulation under light enrichment

X. Liu, Herbert S.J., A.M. Hashemi, G.V. Litchfield, Q. Zhang, A.R. Barzegar

Plant Soil Environ., 2006, 52(4):150-158 | DOI: 10.17221/3359-PSE

Limited information is available regarding the source-sink alterations on soybean yield under whole plant light enriched conditions. The differential responses of yield components for two old and two new cultivars were investigated. The yield sensitivity of the old cultivars to the changes in source strength and light enriched conditions was much greater than that of the two new cultivars. The yield of the new cultivars was more likely sink-limited, and source-limited for the old cultivars. The increased yield by light enrichment was in part due to an increased branch contribution. Pod number per plant was more responsive than seed number per pod. The reduction in pod number by source-sink manipulation was more severe in the old cultivars. Light enrichment increased pod number in the two old cultivars but not in the two new cultivars. Seed size was responsive to changes in the source-sink ratio and changes in the environment. Both pod number or seed size may be increased or decreased if environmental conditions for seed filling are altered.

Phytoremediation based on canola (Brassica napus L.) and Indian mustard (Brassica juncea L.) planted on spiked soil by aliquot amount of Cd, Cu, Pb, and Zn

M. Turan, A. Esringü

Plant Soil Environ., 2007, 53(1):7-15 | DOI: 10.17221/3188-PSE

The use of plants to remove heavy metals from soil (phytoremediation) is expanding due to its cost-effectiveness as compared to conventional methods and it has revealed a great potential. Since contaminants such as Pb or Cd have a limited bioavailability in the soil, methods to facilitate their transport to the shoots and roots of plants are required for successful phytoremediation. The objective of this study was to investigate the effects of addition of different rates (0, 3, 6 and 12 mmol/kg) of ethylene diaminetetraacetate (EDTA) on heavy metal availability in soils contaminated with 50 mg/kg Cd (CdCl2), 50 mg/kg Cu (CuSO4), 50 mg/kg Pb [Pb(NO3)2] and 50 mg/kg Zn (ZnSO4), and on the capacity of canola (Brassica napus L.) and Indian mustard (Brassica junceaL.) plants to uptake Cu, Cd, Pb and Zn in a growth chamber. Results indicated that EDTA application increased heavy metal availability and uptake by plants. Significant differences were obtained in both species and plant parts. As for plant species tested, canola was more effective in the uptake of Cu, Cd, Pb and Zn. Root heavy metal uptake of both species was higher than shoot heavy metal uptake.

Chromosome walking with BAC clones as a method of genome mapping

Z. Kubát

Plant Soil Environ., 2007, 53(10):447-450 | DOI: 10.17221/2198-PSE

Current sequencing projects are often based on random sequencing of genomic libraries followed by contig assembly by means of bioinformatics tools. This approach is convenient for whole genome sequencing projects. Chromosome walking described here is suitable for mapping and sequencing of short genomic regions in species where whole genome sequencing is not possible or for cloning gene from its closest known marker. This method is based on searching for overlapping BAC clones specific for the genomic region of interest.

The use of performance test parameters for selection of gilts before their placement into breeding

N. Kernerová, J. Václavovský, V. Matoušek, Z. Hanyková

Czech J. Anim. Sci., 2006, 51(6):253-261 | DOI: 10.17221/3937-CJAS

The objectives of the paper were to evaluate carcass value in reared gilts on the basis of carcass analysis during the station test of purebred progeny of pigs and ultrasonically with Sonomark-100 or Piglog-105 instruments in the framework of valid methodology for performance testing, and to verify a pos-sibility of prediction of backfat thickness and/or average daily weight gain since birth and lean meat content of gilts as the elements of objectification for the evaluation of their body condition. In total 54 gilts of two breeds were evaluated: the dam breed Czech Large White and the sire breed Czech Large White - sire line. Four-parameter Richards function was used for growth evaluation. The regression function y = 63.870 - 0.447 bt1 - 0.510 bt2 + 0.128 MLLT was applied in ultrasonic instruments for the calculation of lean meat content. We calculated linear regression functions for the conversion of performance testing parameters (gain from birth, average backfat thickness and lean meat content) from live weight on the day of measurement per live weight declared during selections in gilts.

Biological activity of anthropogenic soils after spoil-bank forest reclamation

J. Remeš, R. Šíša

J. For. Sci., 2007, 53(7):299-307 | DOI: 10.17221/2075-JFS

The paper presents the results of relatively long-term research focused on spoil bank revitalization pro-cesses in the North Bohemian Brown Coal Basin after the first three years of observations. The biological activity of soil (namely catalase and phosphatase activity), indicators of basal and potential soil respiration, ammonification and growth, development and nutrition status of forest plantations were selected as indicators of this revitalization process. These parameters were determined in five localities of different age of reclamation where different technological approaches and tree species compositions were used. The results confirm the distinct time dependence of revitalization processes. From the aspect of biological activity older reclamations are close to natural forest soil. The enrichment of top soil layer with organic matter before the plantation (by ploughing in cellulose fibres and peat addition) increased some parameters of soil biological activity. The positive amelioration effect of black alder (Alnus glutinosa) was also confirmed.

Spring malt barley response to elemental sulphur - the prognostic value of N and S concentrations in malt barley leaves

W. Grzebisz, K. Przygocka-Cyna

Plant Soil Environ., 2007, 53(9):388-394 | DOI: 10.17221/2295-PSE

The basic concept of malt barley production is to reach a dilution effect of nitrogen accumulated by grains at maturity. A three-year study was undertaken to establish time courses of nitrogen (N) and sulphur (S) in leaves as the prerequisite tool for total grain yield prognosis. Sulphur application at the lowest rate of 25 kg/ha significantly increased yields of grain in 2001 and 2003. The time course of N and S concentrations in leaves over the growing season showed declining trends for N and variable for S. At mid tillering (BBA-25) both N and S, but at BBA-31 only N concentrations significantly responded to S rates, and in turn affected patterns of N concentration in barley organs up to maturity. Sulphur concentrations and N:S ratios were useful tools to make reliable prognosis of total grain yield of barley at BBA-31 as indicated by the obtained regression equations. The threshold values for N and S in leaves in order to achieve the maximum total grain yield are 0.4% for S and 8.0 for the N:S ratio as presented by the graphical procedure.

The results of manipulated experiments with inoculation of Ips typographus (L., 1758) to spruce trees under various levels of water stress

M. Turčáni, O. Nakládal

J. For. Sci., 2007, 53(20):25-30 | DOI: 10.17221/2159-JFS

Manipulated experiments with males of Ips typographus (L., 1758) were conducted in spruce stands in north-western Slovakia. Some of trees were stressed by a lack of water caused by preparation of roofs under canopy. Inoculation experiments with bark beetles were conducted on such trees. According to results, the differences in attack rates between differently positioned trees on slope were not statistically significant (P = 0.389 for bottom and middle and P = 0.924 for bottom and top, and P = 0.530 for middle and top trees, t-test). Also the differences in attacks rate and the speed of entry holes preparation between more stressed and less-stressed trees were not statistically significant (P = 0.321, t-test). Thus the results of inoculation confirmed that low level of water stress does not lead necessarily to higher attack rate and (neither) faster speed of entry holes preparation. The obtained results are discussed.

The competitive strength factors of the company

H. Chládková

Agric. Econ. - Czech, 2007, 53(7):312-317 | DOI: 10.17221/1154-AGRICECON

PATRIA Kobylí, Inc. is one of the traditional wine-growers and producers of quality wines based in southern Moravia. Farming on 152 hectares, PATRIA Kobylí supplies the market with more than 1 million litres of wine per year. It offers an assortment of 14 whites and 6 blue wines. The company focuses on wines designed for gastronomes and distributed to selected specialized wine-merchants. But since 2003, the sales of the company's wines have been declining. The sales in the individual months of 2006 were the lowest for the last 6 years. But the aim of the company will not be to increase the sales volume but the wine quality and services and sales techniques and so to maintain its position in the market. The company started to analyze its strengths and weaknesses and extended its portfolio of Saint Martin wine and special wines and sparkling wines.

Role of cytokinins in growth correlations between roots and stems in pea (Pisum sativum L.) seedlings

H. Fišerová, J. Šebánek, J. Hradilík, P. Doležel, H. Vítková

Plant Soil Environ., 2006, 52(4):159-163 | DOI: 10.17221/3360-PSE

Pea seeds were swollen in solutions with different concentrations of cytokinin benzyladenine (BA). As compared with controls, a low concentration of BA (0.05 mg/l) did not affect the growth of stems and roots of twelve-day-old seedlings but concentrations of 0.20-4.00 mg/l showed an inhibiting effect; this inhibition was proportional to the concentration of BA. In controls the ratio between the lengths of stems and roots was equal to 1.14, while in seedlings influenced by BA in concentration of 0.20 mg/l its value was significantly lowered to 0.91. Also in six-day-old pea seedlings cultivated under in vitro conditions, BA concentrations of 0.70 and 3.30 mg/l inhibited the growth of roots and epicotyls and significantly increased the production of ethylene (by 150 and 330%, respectively). Three hours after the amputation of the root of five-day-old pea seedlings the level of cytokinin trans-zeatin increased in the apical part of the stem. Within the interval of 48 hours after the amputation of the root the concentration of this plant hormone gradually decreased again. The initial increase in the zeatin level in the stem indicates that the absence of the root induces a reduction of growth-inhibiting effects of roots, which negatively influences the zeatin level in the stem apex at the beginning of germination.

Runoff processes and land use changes in the upper reaches of the Krupá river catchment during the last 70 yearsOriginal Paper

Renata Pavelková Chmelová, Bořivoj Šarapatka, Miroslav Dumbrovský, Přemysl Pavka

Soil & Water Res., 2007, 2(3):77-84 | DOI: 10.17221/2103-SWR

In this paper, the authors summarise the land use changes in the upper reaches of the Krupá river catchment, which is a left tributary of the Morava River. During last 70 years, the catchment was exposed to many important historical events that have been inscribed in the physique of the landscape in a very interesting way. The land use changes, which occurred during the last eight decades in the subcatchment of the Krupá river basin, have been analysed using historical maps, cadastral maps, and both historical and recent aerial photographs of the area. The next step is to estimate, through the CN method and DesQ hydrological model, how the runoff processes in the Krupá River catchment could be influenced by the land use changes.

INDEX OF VOLUME 34 - HORTICULTURAL SCIENCE

editors

Hort. Sci. (Prague), 2007, 34(4):167-169 | DOI: 10.17221/1893-HORTSCI

Derivation of target stocking for forests of Norway spruce vegetation zone in Slovakia

M. Moravčík

J. For. Sci., 2007, 53(8):352-358 | DOI: 10.17221/2183-JFS

The present paper deals with derivation of target stocking in forests of Norway spruce vegetation zone. Target stocking in forests with prevailing ecological and social functions is the stocking when the forest fulfils demanded functions in the best way. For forests in the Norway spruce vegetation zone target stocking was derived by original procedures as an optimum stocking in harmonization of demands on the fulfilment of ecological functions (especially erosion control, hydrological and water protection ones), securing static stability and preconditions for the formation and growth of natural regeneration. We investigated the relations between stocking and indicators of static stability (slenderness coefficient and ratio of crown length to tree height), natural regeneration phases, ground and non-wood vegetation coverage and natural regeneration coverage. The most favourable status of these indicators was found out in stocking 0.7 and in the upper forest limit 0.6.

New Rhizobium leguminosarum bv. trifolii isolates: Evaluation of competitiveness for clover nodule occupancy

T. Šimon, J. Salava

Plant Soil Environ., 2006, 52(10):441-448 | DOI: 10.17221/3464-PSE

An interrelationship between introduced and indigenous rhizobia focused on their competitiveness in nodulation was evaluated in a soil pot experiment. Clover seeds were inoculated by six different gradual concentrations of inoculum of two effective Rhizobium leguminosarum bv. trifolii isolates (inoculation strains 1/2 and 14/2). At the beginning of flowering, clover plants were removed from the pots, and nodules from each pot representing different degrees of inoculum level were taken for reisolate cultivation. The PCR technique was used for the identification of rhizobial reisolates, random amplified polymorphic DNA product patterns were acquired and analysed. Nodule occupation by inoculation strains or indigenous Rhizobium leguminosarum bv. trifolii strains was assessed by comparing the number of nodules formed by inoculation or indigenous strains and inoculation strains competitiveness was calculated. Nodule occupancy by the inoculation strain 1/2 increased sharply with the increase in inoculum dose, whereas in inoculation strain 14/2 more nodules were formed gradually starting from low inoculum level. Competitiveness of inoculation strain 1/2 was calculated as low and was documented by an absence of nodule occupancy in four inoculation levels. On the other hand, competitiveness of the inoculation strain 14/2 was considerably higher, and even in low inoculum dose this strain was more competitive than native rhizobia. Although both the inoculation strains 1/2 and 14/2 were found highly efficient in nitrogen fixation, only the strain 14/2 was able to manifest this characteristic due to the higher competitiveness when applied in lower doses.

Effect of phosphoric fertilizers as a source of sulphur on malt barley total and technological grain yields

J. Potarzycki, W. Grzebisz

Plant Soil Environ., 2007, 53(9):395-402 | DOI: 10.17221/2289-PSE

Malt barley production requires a technology increasing nitrogen use efficiency, because of a high sensitivity of barley total grain yield and quality parameters to external growth factors. In the conducted study an effect of two P fertilizers on the background of N application on total and technological grain yields were studied. The highest total grain yield was harvested on plots fertilized with 60 kg N/ha, irrespective of the P fertilizer type. However, the technological grain yield showed a high year-to-year variability; the highest was recorded in 2001 on the plot fertilized with 60 kg N/ha and the P-PAPR fertilizer. The N and S concentrations and N:S ratios in immature grains at harvest were used to evaluate both yield types. Nitrogen concentration in the final total yield allowed making yields prognosis with the highest probability. The maximum yields of technological malt barley were attainable provided that total S concentration in immature grains at harvest was above 0.23% and the N:S ratio was narrower than 8.0.

Spatio-temporal patterns of the Norway spruce decline in the Beskid Śląski and Żywiecki (Western Carpathians) in southern Poland

W. Grodzki

J. For. Sci., 2007, 53(20):38-44 | DOI: 10.17221/2155-JFS

A dramatic forest decline due to the bark beetle outbreak, which occurs in the Norway spruce stands in the Western Beskidy (southern Poland) since 2003, was started after severe physiological drought during winter time. An analysis describing some spatio-temporal characteristics of this process, with special regard to the patterns of bark beetle occurrence related to root fungal diseases, is presented. In 2003 the bark beetle occurrence level assessed as high and catastrophic was recorded on 40% of the area, while in 2006 - on 59%. The range of Armillaria root disease and bark beetle outbreak increased towards higher altitudes, including the zone above 1,000 m a.s.l. The wind damage in 2004 and 2007, and high temperatures in the summer 2006, further stimulated the increase in bark beetle populations level. Some conclusions on possible development of the outbreak and recommendations concerning related needs in forest protection, are given.

Effect of bacterium Pseudomonas fluorescens and low fungicide dose seed treatments on parasite fungus Aphanomyces cochlioides and sugar beet yield and quality

S. Kristek, A. Kristek, V. Guberac, A. Stanisavljević

Plant Soil Environ., 2006, 52(7):314-320 | DOI: 10.17221/3447-PSE

Effect of sugar beet seed inoculation with a bacterium Pseudomonas fluorescens and treatment by fungicides Thiram 42-S and Dithane S-60 with and without seed inoculation aiming to control Aphanomyces cochlioides - root decay agent was studied. The trial lasted for three years on two soil types (Mollic Gleysols and Eutric Cambisols). The following parameters of sugar beet yield and quality were investigated: root yield, sugar content, sugar in molasses, sugar yield as well as percentage of the infected and decayed plants as a consequence of parasite fungus infestation. The highest average sugar beet root yield was obtained in the variant of the seed treated with fungicide Thiram 42-S and inoculated with bacterium P. fluorescens (85.15 t/ha). However, there were no statistically significant differences (P < 0.05) between the above-mentioned variant and the one with seed inoculated only with bacterium P. fluorescens (84.63 t/ha). The highest mean sugar content of 16.39% was also accomplished during the three-year investigation in the variant of the inoculated seed treated by fungicide Thiram 42-S. All other variants accomplished statistically very significantly lower values of this parameter. The same variant was characterized by the highest mean sugar yield value (12.79 t/ha) on both soil types. Namely, an average sugar yield of the variants inoculated with bacteria was 11.22 t/ha and by 44.22% higher compared to an average yield of non-inoculated variants. The highest percent of the infected and decayed plants (average value on both soil types in the three year investigation) was reported in the control variant (28.92% infected and 25.00% decayed plants) whereas the lowest one was detected in the variant of the seed inoculated with bacterium P. fluorescens in combination with low dose of fungicide Thiram 42-S (4.70% infected plants and 2.88% decayed plants). An average percent of the infected plants inoculated with bacterium P. fluorescens was 9.13% whereas the aforesaid value of the plants infected with parasitic fungus A. cochlioides in non-inoculated variants was by 146.00% higher being 22.42%.

The role of Fe- and Mn-oxides during EDTA-enhanced phytoextraction of heavy metals

M. Komárek, P. Tlustoš, J. Száková, V. Chrastný, J. Balík

Plant Soil Environ., 2007, 53(5):216-224 | DOI: 10.17221/2203-PSE

In several cases ethylenediaminetetraacetic acid (EDTA) proved to be an efficient mobilising amendment during chemically enhanced phytoextraction of heavy metals. The presence of Fe-(hydr)oxides and their dissolution after the addition of EDTA can limit the phytoextraction of the targeted heavy metals due to the high stability of the formed Fe(III)EDTA complexes. This study has focused on the influence of Fe- and Mn-oxides and hydroxides dissolution on heavy metal uptake by Zea mays in a two-year EDTA-enhanced phytoextraction process. Incubation experiments and speciation modelling proved the increased concentrations of Mn and Fe through the dissolution of Mn-and Fe-(hydr)oxides. Furthermore, increased Fe and Mn accumulation was observed in maize plants after the second year of the phytoextraction process. Therefore, the presence of Mn- and especially Fe-(hydr)oxides proved to be a limiting factor during EDTA-enhanced phytoextraction of heavy metals from contaminated soils.

Operational zones, countryside, network society

S. Hubík

Agric. Econ. - Czech, 2007, 53(11):491-494 | DOI: 10.17221/977-AGRICECON

An important issue in the theory of social constructivism is the issue of spatial arrangement. Space is grasped as the primary/secondary zone of operation. The secondary zone of operation is determined by the use of technical means. Technically conditioned social networks currently give a new dimension to both zones. From this point of view, the new solutions for the network/agglomeration economies arise: networks may substitute for agglomerations.

Direct and secondary effect of liming and organic fertilization on cadmium content in soil and in vegetables

A. Zaniewicz-Bajkowska, R. Rosa, J. Franczuk, E. Kosterna

Plant Soil Environ., 2007, 53(11):473-481 | DOI: 10.17221/2305-PSE

A direct and secondary effect of liming and organic fertilization on the cadmium content in soil and in vegetables was examined. Celeriac (Apium graveolens L. var. rapaceum) was cultivated in the first year after lime application and organic fertilization whereas leek (Allium ampeloprasum ssp. porrum J. Gay) was grown in the next year. Soil was limed with a calcium carbonate fertilizer at the rate of 2.0 t CaO/ha. The following were applied as organic fertilizers: farmyard manure (60 t/ha), rye straw (4 t/ha), rye and winter vetch, both the plants cultivated as winter catch crops for green manure. Liming significantly reduced the available cadmium content in the soil in the first and second year after its application. Also, it significantly reduced the cadmium content in celeriac and leek compared with no-liming cultivation. Organic fertilization, especially farmyard manure and straw, significantly reduced the soil available cadmium content as compared to the untreated control (without organic fertilization). The aforementioned factor significantly reduced the cadmium content in the examined vegetables. Cadmium lowest content in celeriac leaves and leek was recorded after the application of farmyard manure. A combined application of liming and organic fertilization in the form of farmyard manure most beneficially influenced celeriac leaves with respect to their cadmium content.

Feeding ecology of pine shoot beetles (Tomicus spp.) in tree crowns of Scots pine (Pinus sylvestris L.) stands under one-year outbreak

A. Borkowski

J. For. Sci., 2007, 53(10):445-451 | DOI: 10.17221/2084-JFS

Studies were carried out in southern Poland during 2002-2006 in Scots pine stands under the effect of an outbreak of pine shoot beetles. The qualitative aspects of beetle feeding in tree crowns, studied on the basis of fallen shoots collected on experimental plots, are presented in this paper. The beetle numbers affected the age distribution of damaged shoots and the proportion of multiple attacks. The proportions of one-year-old shoots and the numbers of shoots with more than two attacks increased in the marginal part of the stand in the year of intensive feeding of beetles and in the subsequent year. A similar proportion of shoots with two attacks in both stands under investigations in individual study periods, with no relation to beetle numbers, does not permit to use this characteristic for forecasting purposes. The average length of tunnels in shoots attacked once reached 20 mm at maximum. The average length of tunnels (measured from the place of shoot disruption) was greater in shoots with two attacks than in shoots with a single one (P < 0.0001). The difference was not significant (P = 0.3429) only in stand B during the study season 2004-2005. The majority of the tunnels made in apical portions of shoots with two attacks damaged the tissue of apical shoots. The distance between the base of the second tunnel and the shoot apex in shoots with two attacks, and its significant (P < 0.01) linear relationship with the length of beetle tunnels, indicated a high nutritional quality of apical portions of shoots.

Assessment of metal contamination in the upper reaches of the Tichá Orlice River

Z. Svobodová, O. Čelechovská, J. Kolářová, T. Randák, V. Žlábek

Czech J. Anim. Sci., 2004, 49(10):458-464 | DOI: 10.17221/4332-CJAS

The aim of the present study was to assess metal contamination in the same reaches of the river, and thus to help explain unsatisfactory reproduction results in the reproduction of salmonoid fish. The contamination assessment was based on measuring metal concentrations in the brown trout (Salmo trutta morpha fario) and some bottom sediment samples. The samples were collected in June 2000 and 2001 at two collection sites from theTicháOrliceRiver (Červená Voda - 103rd river km; Lichkov - 93rd river km) and its tributary Kralický Brook (100th river km). At each of the sites, 14 brown trouts were collected in each of the periods of monitoring. The AAS method was used to determine the total mercury, arsenic, cadmium, lead, copper, zinc, chromium and nickel contents in the muscle tissue of the fish and in aquatic sediments. The Kralický Brook is an important anthropogenic source of metal contamination (particularly of mercury and copper) for theTicháOrliceRiver. The highest concentrations of mercury in muscles of brown trout were found at the Kralický Brook (0.37 ± 0.08 and 0.40 ± 0.08 mg/kg) and Lichkov (0.41 ± 0.10 and 0.34 ± 0.07 mg/kg) in 2000 and 2001 and the lowest concentration at Červená Voda (0.017 ± 0.02 mg/kg in the same years). Significantly higher concentrations of arsenic (in 2000: 0.30 ± 0.08 mg/kg; in 2001: 0.38 ± 0.07 mg/kg) were found in the muscle tissue of the brown trout collected at Červená Voda than at the downstream site Lichkov (in 2000: 0.18 ± 0.09 mg/kg;in 2001: 0.14 ± 0.07 mg/kg). The authors hypothesize that the difference was due to different conditions (principally water temperature). It seems reasonable to assume that unsatisfactory results in the reproduction of fish from the upper reaches of theTicháOrliceRiver are due not only to organic pollutants but also to mercury compounds that are classified among suspect endocrine disruptors.

Hymenoptera (Aculeata) in birch stands of the air-polluted area of Northern Bohemia

E. Kula, P. Tyrner

J. For. Sci., 2003, 49(4):148-158 | DOI: 10.17221/4690-JFS

The Hymenoptera (Aculeata) fauna was studied in birch stands (Betula pendula Roth) of colder areas of Northern Bohemia using the method of Moericke's yellow traps. Altogether 159 species were trapped; the most important were Andrena lappona, Vespula vulgaris, Halictus sp., Trypoxylon minus and Vespula rufa. Only 12.7% of the species are widely spread in this ecosystem type. In 1990-1994 and in 1995-1999 we compared the abundance of the fauna and discovered that many species of the families Apidae and Sphecidae receded from the birch stands due to changing site conditions (light, weed infestation).

Static stability of forest stands in the seventh altitudinal vegetation zone in Slovakia

B. Konôpka, J. Konôpka

J. For. Sci., 2003, 49(10):474-481 | DOI: 10.17221/4719-JFS

Models evaluating static stability (resistance to breaking or uprooting of trees caused by wind, snow or ice) of forest stands in the seventh altitudinal vegetation zone were determined. The empirical material came from 180 research plots (High Tatra and Low Tatra Mountains) established within the research project Research on methods for mountain forest management based on sustainable Development. Static stability was characterized by the slenderness ratio that was calculated from the mean height and diameter of target trees. Then the particular forest stands were categorized with regard to slenderness ratio, mean diameter and absolute site class using either tables or graphic models. Particularly, four static stability classes were made up: 1 - very good, 2 - good, 3 - sufficient, and 4 - insufficient. Practical application of the models is shown for forest stands grown in the area of Vajsková and Lomnistá valleys.

Impact of skidder and high-lead system logging on forest soils and advanced regeneration

M. Modrý, D. Hubený

J. For. Sci., 2003, 49(6):273-280 | DOI: 10.17221/4701-JFS

The applied skidding technology strongly influences the impact of harvest on the ecosystem and success of natural regeneration. The impact of skidder SLKT 81 and high-lead system Larix 3T on forest soil and natural regeneration was compared under analogical site and stand conditions in a production beech forest in the environs of Brno, Czech Republic. The skidder was found to have greater effects on the soil surface consistency, soil properties and natural regeneration than the high-lead system operations. Although high-lead system operations are more friendly to all parts of forest ecosystem, the skidder may not cause excessive damage when applied under suitable terrain and climatic conditions.

Horizontal and vertical variability of heavy metals in the soil of a polluted area

K. Šichorová, P. Tlustoš, J. Száková, K. Kořínek, J. Balík

Plant Soil Environ., 2004, 50(12):525-534 | DOI: 10.17221/4069-PSE

The Příbram region belongs to the most polluted areas in the Czech Republic. Atmospheric deposition of potentially toxic elements from lead smelter represents the main source of contamination in this region. In this study, the most polluted location intensively used for agriculture situated northeast from the source of contamination was investigated. The individual sampling points were positioned by GPS and representative samples were taken from 0-60 cm split into three20 cmlayers. In the soil samples total Pb and Cd contents, plant available contents of these toxic elements and soil pH were determined. The total Cd content at the investigated site reached up to 13 mg/kg and Pb up to 2500 mg/kgin the top layer. The concentration of both elements decreases with depth and in the 40-60 cm layer the maximum content of only 6 mg Cd/kg and 400 mg Pb/kg was found. The plant available the content of Pb and Cd in the soil is related to the pH value. The correlation coefficient of exponential regression for Cd is -0.799 and for Pb is -0.787. The obtained data was processed by Surfer 7 software resulting in digital maps of horizontal and vertical contamination of this location. This observation confirmed the airborne source of soil contamination. However, some of the individual sampling points suggested local geogenic contamination of the soil where more detailed further research is required.

Pancarpal and pantarsal arthrodesis applications using compression plates in dogs

S. Ozsoy, K. Altunatmaz

Vet Med - Czech, 2004, 49(4):109-114 | DOI: 10.17221/5683-VETMED

Pancarpal arthrodesis was carried out in 6 dogs and pantarsal arthrodesis in 3 dogs, which could not use their extremities due to various reasons. For arthrodesis, 3 and 4 mm thick compression plates were used. The application was done on the dorsal aspect. Fusion was radiographically seen to have formed between post-operative 45-75 days in 10 joints belonging to 9 cases. The plate broke in one case. With the exception of 1 case, functional recovery was achieved in all cases accompanied with varying degrees of lameness. While the material was removed from 1 case in which the plate broke and another in which a chronic wound developed in the operation site, plates were not removed from any of the other cases.

Evaluation of the growth and health of different poplars in the Latorica area in Východoslovenská nížina conditions

Š. Kohán

J. For. Sci., 2003, 49(10):482-489 | DOI: 10.17221/4720-JFS

The paper presents the results of evaluating the growth and health of 20 different poplars from the Aigeiros group in 30-year populetum Leles on uninundated alluvia of the Latorica River in ecological conditions of the lowland Východoslovenská nížina. The populetum is situated on medium-heavy loamy soils in the group of forest site types Ulmeto-Fraxinetum carpineum. The results of evaluation document that out of the investigated poplar clones the poplars I-214, I-476, Blanc du Poitou, Flachslanden and P. nigra (Baka 5) had the best height and diameter growth and maximum volume production. Their health status was also very good. The lowest volume production was determined in P. nigra (009/66 ČR), I-455 and Grandis, and the worst health was found out in Grandis, P. nigra (Pavlovce 1) and P. nigra (Ivachnova 1). These results will facilitate to include the poplars I-476 and Flachslanden in the assortment of regionalized poplars for the lowland area of Východoslovenská nížina.

Early stadiums of floodplain forest succession in a wide river beds upon an example of Bečva

J. Klečka

J. For. Sci., 2004, 50(7):338-352 | DOI: 10.17221/4631-JFS

In the years 1999-2001 early stadiums of succession development of a floodplain forest were monitored in the wide bed of the Bečva River formed during the floods in 1997. Changing site conditions were investigated and the vegetation of pebble beds was repeatedly mapped in detail. In dependence on the site conditions main types of biotopes were described. The vegetation data were evaluated in accordance with the life form and ecological claims of the identified species. The results indicated an increasing differentiation of the originally relatively homogeneous environment owing to fluvial processes and progress of vegetation. Generally hemicryptophytes and hemiheliophytes were thriving above all, the dominance of Phalaris arundinacea was still growing. As for the woody species, especially willows asserted themselves from the beginning, solitarily and weaker in vitality representatives of other genera were present at drier sites. The identified specimen of Myricaria germanica was probably planted artificially. As concerns neophytes, only Reynoutria japonica was spreading significantly but in a very uneven way. Generally, this development of similar communities only little documented in this region corresponds to STG Saliceta fragilis inf.

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