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Results 1501 to 1530 of 1934:

Effect of triacylglycerols of medium-chain fatty acids on growth rate and mortality of rabbits weaned at 25 and 35 days of age

E. Skrivanova, V. Skrivanova, Z. Volek, M. Marounek

Vet Med - Czech, 2009, 54(1):19-24 | DOI: 10.17221/3079-VETMED

Three hundred Hyplus rabbits reared on a commercial farm were weaned at the age of 25 days and 300 rabbits were weaned at the age of 35 days. Early-weaned and conventionally weaned rabbits were assigned to three groups and fed diets supplemented with protected palm fat (PPF), coconut oil (CO) and an oil containing triacylglycerols (TAG) of caprylic and capric acid (Akomed R) at 10 g/kg. The principal fatty acids in these supplements were palmitic, lauric and caprylic acid, respectively. Diets were fed until slaughter at 77 days of age. Mortality of early-weaned rabbits fed the diet supplemented with oil containing TAG of caprylic and capric acid (23%) was significantly lower than that of rabbits fed PPF (45%), and non-significantly lower than mortality of rabbits fed CO (37%). Corresponding mortality rates in rabbits weaned at 35 days of age were 6, 14 and 16%. In all groups, the highest mortality occurred in the 2nd and the 3rd week after weaning. The final body weights of surviving early-weaned rabbits were not significantly different. In conventionally weaned rabbits, however, final body weight was significantly lower in rabbits fed PPF. It can be concluded that under practical field conditions early weaning represents a risk for animal health and leads to a high mortality of young rabbits. The negative effect of early weaning can be alleviated by commercially available TAG of caprylic and capric acid.

Forest watershed runoff changes determined using the unit hydrograph method

V. Černohous, P. Kovář

J. For. Sci., 2009, 55(2):89-95 | DOI: 10.17221/94/2008-JFS

Unit hydrograph is a basic method to show changes in runoff in the watershed. The investigation of runoff changes was carried out in the U Dvou louček watershed situated at the summit part of the Orlické hory Mts., East Bohemia. The waveform ordinates of recession limbs of unit hydrographs obtained using a common approach had to be approximated by the least-squares method. Final hydrographs reflected both drainage treatment and forest stand growth influencing the runoff from the watershed. Both factors increase culmination in synergy and reduce runoff on the recession limb of the hydrograph. We confirmed increased maximum runoff taking up 25-30% of the total runoff time when waterlogged sites were drained. The culmination increased by 0.2-0.8 mm/hour indicates the runoff increased by 2-8 m3/ha/hr.

Microbial biomass dynamics after addition of EDTA into heavy metal contaminated soils

G. Mühlbachová

Plant Soil Environ., 2009, 55(12):544-550 | DOI: 10.17221/124/2009-PSE

An incubation experiment with addition of EDTA and alfalfa into soils contaminated with heavy metal over 200 years was carried out in order to evaluate the EDTA effects on microbial properties. Alfalfa was added to soils together with EDTA to examine its abilities to improve microbial activities affected by EDTA. The obtained results showed that the addition of EDTA led to a significant decrease of microbial biomass C during the first 24 days of incubation. At the end of the experiment the microbial biomass C significantly increased quite close to the original level. The EDTA amendment caused, probably due to the toxic effects, a significant increase in respiratory activities and of the metabolic quotient qCO2. An addition of alfalfa significantly improved the microbial biomass C contents in arable soils treated together with EDTA. Both, respiratory activities and qCO2 significantly increased after the soil treatment with EDTA together with alfalfa. EDTA alone decreased the microbial biomass, alfalfa alone as organic substrate was mineralised and utilised by soil microorganisms for their metabolism.

Sensitivity of Assessors to Ferrous Salts

Z. Panovská, A. Váchová, J. Řeřichová

Czech J. Food Sci., 2009, 27(10):S333-S336 | DOI: 10.17221/1082-CJFS

Taste is the chemical sensation whose function is not very well known. Recently it was shown that the range of taste is more extensive than the five basic taste sweet, salty, bitter, sour and umami. A metallic taste has been suggested as another basic taste, but its mode of perception is not well understood and has not been really accepted in the taste literature. Ferrous sulphate solutions were presented to the assessors so their sensitivity and best estimate thresholds (BET) were measured. The best estimated threshold range was 0.00049-0.00669 g/l for demineralised water, 0.00079-0.00669 g/l for distilled water and 0.00108-0.00669 g/l for tap water.

The visfatin (NAMPT; PBEF1) gene polymorphisms and associations with meat performance traits in three pig breeds kept in the Czech Republic

J. Zrůstová, A. Knoll, T. Urban, S. Čepica

Czech J. Anim. Sci., 2009, 54(10):443-447 | DOI: 10.17221/1673-CJAS

Visfatin encoded by the NAMPT gene (nicotinamide phosphoribosyltransferase, formerly also known as PBEF - pre-B cell colony-enhancing factor) is suggested to play a role in lipid metabolism and pathophysiology of diabetes mellitus type 2. A new microsatellite SCZ004 was detected within intron 9 of the NAMPT gene. In Czech Large White (n = 95) frequencies of alleles 282, 286, 287, 299, and 304 were 0.02, 0.39, 0.07, 0.04, and 0.48, respectively. Allele 286 was predominant also in Landrace (n = 11) and Black Pied Prestice (n = 11) breeds. Association analysis was carried out between previously reported SNP AM999341:g.669T>C in intron 9 of the NAMPT gene and backfat thickness, average daily gain and lean meat content in Czech Large White (n = 215), Black Pied Prestice (n = 96) and Landrace (n = 105). The CC genotype was associated with higher backfat thickness (

How do lepidopteran seasonal guilds differ on some oaks (Quercus spp.) - A case study

M. Turčáni, J. Patočka, M. Kulfan

J. For. Sci., 2009, 55(12):578-590 | DOI: 10.17221/53/2009-JFS

The differences between oak lepidopteran communities were studied in Slovakia in 1993 and 1994. Sampling was undertaken between April and October on 3 oak species (Quercus robur, Q. petraea, Q. rubra). Biological traits of larvae were examined in order to explain differences in seasonal guilds among oaks. Communities varied in structure and abundance. Species richness in four seasonal guilds (flush, late spring, summer and autumn feeders) had a similar pattern on each of the studied oak species. The guild of flush feeders had the richest species assemblage, followed by the late spring feeder guild and both guilds were significantly richer than the summer feeder guild and autumn feeder guild.

Influence of Cadophora finlandica and other microbial treatments on cadmium and zinc uptake in willows grown on polluted soil

M.N. Dos Santos Utmazian, P. Schweiger, P. Sommer, M. Gorfer, J. Strauss, Wenzel W.W.

Plant Soil Environ., 2007, 53(4):158-166 | DOI: 10.17221/2310-PSE

We conducted a pot experiment to evaluate the Cd and Zn accumulation in leaves and roots of Salix smithiana (BOKU-03DE-001) and S. caprea (BOKU-01AT-004) clones grown on a metal-contaminated soil as affected by native microbes extracted from the same experimental soil, and the fungus Cadophora finlandica. Plant biomass production of S. smithiana was decreased in all the treatments compared to the sterilized control. In contrast, S. caprea grew best on the non-sterilized soil. Similar effects were observed for plant Zn and Cd contents. Microbial treatments affected metal accumulation differently in the two Salix species. The effects of the microbial treatments on biomass and metal content of leaves were not related to the degree of mycorrhization. A comparison with literature data suggests that the plant response to microbial inoculation in terms of metal accumulation may depend on the plant-internal metal concentration. Our findings also illustrate a difficulty of successful rhizosphere management using metal-tolerant microbial isolates to further enhance the phytoextraction process.

Impacts of root sulfate deprivation on growth and elements concentration of globe amaranth (Gomphrena globosa L.) under hydroponic condition

M.Y. Wang, L.H. Wu, J. Zhang

Plant Soil Environ., 2009, 55(11):484-493 | DOI: 10.17221/70/2009-PSE

Sulfur (S) regarded as the fourth key element is mainly taken by the plant roots. However, some plants can also absorb atmospheric sulfides, which may be of great importance for ameliorating the environment and for farming as a green organic S fertilizer used to balance insufficient soil S content for intensive cultivation in China; H2S and mainly SO2 are emitted to air as a result of the rapid industrialized and economic development. Globe amaranth (Gomphrena globosa L.) might be one of the plants that can use atmospheric sulfides for its growth. Therefore the effects of sulfate deprivation from root on its growth, S status and other elements concentration under hydroponic culture were explored firstly. Based on measurements of plant growth, biomass, nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), S, iron (Fe), manganese (Mn), copper (Cu), zinc (Zn), boron (B), and molybdenum (Mo) concentration, the results showed that S concentration in flower, shoot and root of plant without root sulfate supplied was increased with plant growth and development, symptoms of S deficiency disappeared and other elements concentration in plant tended to be nearly the same as the root sulfate-supplied plants. The interesting results might imply that globe amaranth may be able to live on the atmospheric sulfides as sulfur source.

Species composition in low mountain beech (Fagus sylvatica L.) stands in the Bieszczady National Park under the global warming

D. Sugiero, R. Jaszczak, G. Rączka, P. Strzeliński, A. Węgiel, A. Wierzbicka

J. For. Sci., 2009, 55(5):244-250 | DOI: 10.17221/15/2009-JFS

The author analyzes the changes in the tree species composition of Dentario glandulosae-Fagetum Klika 1927 em. Mat. 1964 in the mountain stands of Bieszczady National Park in 1993-2003. The analysis takes into account the changes over a ten-year period in the number and volume structure of each tree species in each stand layer: young natural regeneration, undergrowth, and mature stand. Additionally, after comparing the results with the natural Carpathian forests' structure, the adaptation level of the present tree species composition to the current climate and soil conditions, as well as probable directions of future changes have been assessed. A ten-year period is too short to find significant changes in stand species structure but it is possible to see some trends: beech share in stands is increasing and fir is decreasing.

Allelopathic properties of knotweed rhizome extracts

N. Vrchotová, B. Šerá

Plant Soil Environ., 2008, 54(7):301-303 | DOI: 10.17221/420-PSE

Our objective was to determine which rhizome extract from Japanese knotweed, Giant knotweed or Bohemian knotweed has the most significant inhibition effect on the germinated seeds. The seeds of white mustard were incubated with the extracts for two days under laboratory conditions. We monitored differences in number of germinated seeds, length of radicles, hypocotyls and root/shoot ratio between the control and experimental seeds. Inhibitory effect of extracts from dried knotweed rhizomes was confirmed, but without differences among tested plants. A higher allelopathic effect was revealed in the case of extract from aboveground parts.

Phytoextraction of cadmium, copper, zinc and mercury by selected plants

L. Kacálková, P. Tlustoš, J. Száková

Plant Soil Environ., 2009, 55(7):295-304 | DOI: 10.17221/100/2009-PSE

During the years 2006 and 2007 the phytoextraction ability of maize (Zea mays), willow-tree (Salix smithiana) and poplar (Populus nigra × P. maximowiczii) to accumulate cadmium, copper, mercury and zinc was investigated. Small scale field experiment was carried out on soil contaminated with chemicals from the waste incineration plant in Hradec Kralové (Czech Republic). Screening of this allotment showed very different contamination of all observed risk elements on places where the material intended to be burnt without safety of leakage into soil. Grown plants showed the different accumulation of observed elements in plant tissues as well as the influence of total content of the risk elements in soil. The highest Cd (1.5-1.73 mg/kg) and Zn (242-268 mg/kg) concentrations were found in willow-tree biomass mainly in the leaves. Cu and Hg were mostly accumulated by maize roots (14.6-15.8 mg Cu/kg and 1.3-7.4 mg Hg/kg) and lower amount was found out in willow-tree leaves again. In reference to total production of each plant the maximum Cd and Zn uptake by aboveground biomass was found in poplars (201 mg Cd/m2 and 38 200 mg Zn/m2) and maize, which showed high Zn uptake. The biggest amount of copper (2563 mg Cu/m2) was accumulated by aboveground maize biomass on the collection point with the highest Cu concentration in soil and by poplar (2394 mg Cu/m2) on the other collection point. The highest Hg uptake differs in reference to total Hg content in soil; willow-tree has the highest uptake on the place with lower Hg content in soil (44.6 mg Hg/m2) and maize has the highest uptake on the place with higher Hg content in soil (92 mg Hg/m2).

Evaluation of monitoring on Modrava catchments

Jiří PAVLÁSEK, Jana ŘEDINOVÁ, Petra SKALSKÁ

Soil & Water Res., 2009, 4(10):S66-S74 | DOI: 10.17221/475-SWR

In this paper is presented the comparison of the selected hydrometeorological data from two experimental micro-scale catchments Modrava 1 (0.1 km2) and Modrava 2 (0.17 km2) in upper parts of Bohemian Forest. These catchments differ mainly in the vegetation cover - a dead forest with very young trees (Modrava 1) and primary forest clearings with 10 to 15-year old young forest (Modrava 2). For comparison were used the data monitored close to the catchments outlets during the hydrological year 2007. Average hourly rainfall and runoff data were analysed. During the winter season, snow water equivalents were measured and the maximum value was added to the rainfall amount measured during the vegetation season for the estimation of total year precipitation on each catchment. The data of the air temperature and water conductivity measured in hourly time intervals were also compared. For the estimation of differences between the monitored data sets the cumulative values of the characteristics observed during whole year were computed. It follows from the comparison of the time series that the time rainfall distribution was similar during the year on both catchments with a higher total year precipitation and hour intensities on the catchment Modrava 2. The time distribution and total runoff depth were similar on both catchments. On Modrava 1 a faster recession of hydrographs could be seen which might relate to a lower retention capacity. The value of the water conductivity on the catchment Modrava 1 depended more on the changes of the runoff depth. The maximal values occurred during the peak discharges or in time of hydrographs rising. This fact can be the result of a lower stability of the soil profile in the catchment with dead forest cover.

Combined iridencleisis and posterior sclerectomy in surgical treatment of glaucoma secondary to uveitis in a dog: a case report

M. Lew, S. Lew

Vet Med - Czech, 2009, 54(3):142-148 | DOI: 10.17221/3052-VETMED

In early diagnosed and causally treated cases of secondary glaucoma, it is possible to save the sight in a glaucomatous eye and to preserve the sight in a healthy eye. The most common causes of secondary glaucoma include anterior uveitis, in which diverse pathological processes can lead to an increase in IOP. In cases of treating glaucoma secondary to uveitis with annular posterior synechiae in connection with peripheral anterior synechiae, iridencleisis is the method of choice. This article presents the results of the eight-month treatment of such a case with iridencleisis combined with posterior sclerectomy. This method makes it possible to increase the area of aqueous humour outflow to the subconjunctival space. The treatment resulted in the reduction of IOP in the left eye from the preoperative value of 72 mmHg to 15 mmHg, which was maintained at a constant level during the eight-month period following the surgery. Sight assessment in the operated eye, carried out on the basis of PLR, menace and dazzle response, brought a moderately positive result.

Up-regulation of sucrose-P synthase in rice under elevated carbon dioxide and temperature conditions

K.B. Sujatha, D.C. Uprety, D. Nageswara Rao, P. Raghuveer Rao, N. Dwivedi

Plant Soil Environ., 2008, 54(4):155-162 | DOI: 10.17221/388-PSE

Basmati rice (Oryza sativa L.) cultivars viz. PRH-10 (pusa rice hybrid-10) and PS-2 (Pusa Sugandh-2) were grown under two different day/night temperatures (31/24°C, 35/28°C) at ambient (370 μmol/mol) and elevated (550 μmol/mol) carbon dioxide (CO2) concentration, respectively, to characterize how an increase in CO2 and temperature affects rice photosynthesis and carbohydrate metabolism. At elevated CO2, the photosynthetic rates increased under both the temperature regimes, compared with plants grown at ambient CO2. The photosynthetic rate, sucrose-P synthase (SPS) activity and accumulation of soluble sugars and starch were higher in PRH-10 (pusa rice hybrid-10), compared to PS-2 (Pusa Sugandh-2). Elevated temperature decreased the photosynthetic rates both under ambient and elevated CO2 conditions. The SPS (sucrose-P synthase) activity and the accumulation of soluble sugars and starch were enhanced at elevated CO2 under both temperature regimes compared with plants grown at ambient CO2. The up-regulation of SPS (sucrose-P synthase) under elevated CO2 and temperature would be beneficial for growth and productivity of rice plants for the future climatic conditions.

Contents of Heavy Metals in Different Saccharides Fractions of Potato Tubers

J. Musilová, T. Tóth, J. Árvay

Czech J. Food Sci., 2009, 27(10):S382-S385 | DOI: 10.17221/1067-CJFS

In this work the Cd, Cu and Zn accumulation in potatoes, their influence on starch, water-soluble (WSS) and water-insoluble saccharide (WIS) contents and content of heavy metals in various saccharide fractions of potatoes were determined. The fraction of WSS was isolated by Somogyi method, the WIS fraction was obtained from delipided portion of potatoes. Enhanced pseudototal Cd contents in relationship to limit value 0.7 mg/kg of soil were determined in 13 soil samples (0.72-1.06 mg/kg). Contents of Zn and Cu were lower than their limit values in all observed soil samples. Observed heavy metals have not influence on their accumulation in potatoes, the Cd content in potatoes (0.0015-0.0042 mg/kg f.m.), Cu (0.0590-0.1780 mg/kg f.m.) and Zn contents (0.1887-0.3517 mg/kg f.m.) were also lower than their limit values. The proportion of observed heavy metals in selected saccharide fractions: Cd (mg/kg): 0.017-0.140 (starch), 0.0133-0.2293 (WIS), 0.8711-109.7713 (WSS); Cu (mg/kg): 0.067-1.433 (starch), 0.2844-6.9877 (WIS), 18.0134-1070.5216 (WSS); Zn (mg/kg): 6.667-66.300 (starch), 0.7869-23.3673 (WIS), 101.4842-4020.790 (WSS)

How does legacy of agriculture play role in formation of afforested soil properties?

D. Kacálek, J. Novák, D. Dušek, J. Bartoš, V. Černohous

J. For. Sci., 2009, 55(1):9-14 | DOI: 10.17221/74/2008-JFS

Soil properties of forest ecosystems depend on synergy of both parent material and organisms living in the soil, i.e. tree species communities including related plant and animal species. However these soils were not left intact being converted into agricultural land; addition of both nutrients and organic matter and cultivation using tillage led to increased fertility of topsoil. Even long-term afforested soils show differences which are considered as legacy of past agriculture. The change remains detectable for decades; though the altered properties are obvious especially couple of years after planting (approximately 10 years). We found increased concentrations of nutrients (P, K, Ca, and Mg) and subsequent increased base saturation (V %) in former tilled soil only. Moreover, there were no differences between topsoil and subsoil properties (69% and 72%, respectively). In addition to significantly lower saturation (both 0-10 cm and 11-30 cm layers) detected in the long-term-forest and 50-year-afforested (both covered with Norway spruce stands) soils in comparison with adjacent 10-year-old afforestations, there was found significantly lower base saturation in topsoil horizons compared to underlying ones.

Corn yield response to partial rootzone drying and deficit irrigation strategies applied with drip system

A. Yazar, F. Gökçel, M.S. Sezen

Plant Soil Environ., 2009, 55(11):494-503 | DOI: 10.17221/96/2009-PSE

This paper evaluates the effect of partial root zone drying (PRD) and deficit irrigation (DI) strategies on yield and water use efficiency of the drip-irrigated corn on clay soils under the Mediterranean climatic conditions in Southern Turkey. Four deficit (PRD-100; PRD-75; PRD-50; and DI-50) and one full irrigation (FI) strategies based on cumulative evaporation (E pan) from class A pan at 7-day interval were studied. Full (FI) and deficit irrigation (DI-50) treatments received 100 and 50% of Epan, respectively. PRD-100, PRD-75 and PRD-50 received 100, 75 and 50% Epan value, respectively. The highest water use was observed in FI as 677 mm, the lowest was found in PRD-50 as 375 mm. PRD-100 and DI-50 resulted in similar water use (438 and 445 mm). The maximum grain yield was obtained from the FI as 10.40 t/ha, while DI-50 and PRD-100 resulted in similar grain yields of 7.72 and 7.74 t/ha, respectively. There was a significant difference among the treatments with respect to grain yields (P < 0.01). The highest water use efficiency (WUE) was found in PRD-100 as 1.77 kg/m3, and the lowest one was found in FI as 1.54 kg/m3.

Inheritance of some pomological traits in Minaret × Betinka apricot progeny

B. Krška, J. Pramuková, M. Vachůn

Hort. Sci. (Prague), 2009, 36(3):85-91 | DOI: 10.17221/32/2008-HORTSCI

In the years 2005, 2006, and 2007 the described pomological characteristics were evaluated and both heritability and correlation coefficients of the determined characteristics of parents and progeny were estimated for the Minaret × Betinka apricot hybrid population. Estimated heritability of fruit weight, over colour and flesh consistency was approximately 0.9. Heritability of flesh colour, fruit attractiveness and fruit flavour ranged from 0.6 to 0.9. The correlations show a strong dependence of the following characteristics of parent varieties and progeny: over colour and fruit attractiveness. Medium strong dependence was determined in the following characteristics: fruit colour and fruit flavour. Weak dependence was found in the case of fruit size.

Growth of wild cherry (Prunus avium L.) in a mixture with other species in a demonstration forest

R. Stojecová, I. Kupka

J. For. Sci., 2009, 55(6):264-269 | DOI: 10.17221/71/2008-JFS

Wild cherry is one of the noble hardwood species that increase the biodiversity of our forests and at the same time it could increase the income for forest owners. The preconditions for achieving these goals are the high quality of stem and appropriate silvicultural management. This means that wild cherry should occupy the main crown layer in the stand. The height/frequency diagram depicts two groups of wild cherry trees in the stand belonging to dominant/codominant and suppressed tree classes. Height periodic increment (measured between the years 2001 and 2007) is significantly (p < 0.01) different in these two groups confirming that there is no transition chance for the trees from the suppressed group to become a part of the main crown layer and play the role of future crop tree. The same is true of the diameter/frequency diagram which also has a two-peak shape remaining also at the end of the surveyed period. Our result suggests that silvicultural care should be focused only on trees belonging to future crop trees.

Interannual dynamics of available potassium in a long-term fertilization experiment

M. Madaras, J. Lipavský

Plant Soil Environ., 2009, 55(8):334-343 | DOI: 10.17221/34/2009-PSE

Dynamics of the plant-available potassium (K) has been studied in polyfactorial long-term fertilization experiments since 1980. The fertilization scheme includes 10 combinations of K muriate and farmyard manure application rates (annually 0-230 kg K/ha). At medium treatment (annually 153 kg K/ha), the K balance within an 8-year crop rotation reflected crop specific K application rates with positive annual balances in years of growing silage maize and sugar beet (high K input), and negative in two years of growing alfalfa. Available K clearly corresponded to the dynamics of the K balance, with statistically significant fluctuations from 88 to 149 mg K/kg within one crop rotation cycle. Periodic fluctuations of available K induced by crop rotation were observed also in non-fertilized treatments. The variability of available K contents was influenced primarily by crop plants and experimental unexplained factors; interannual weather fluctuations and field differences were of low significance. In the paper, the importance of interannual K dynamics for the construction of correct long-term time trends is shown and discussed.

Rutting and soil displacement caused by 450C Timber Jack wheeled skidder (Asalem forest northern Iran)

R. Naghdi, I. Bagheri, M. Lotfalian, B. Setodeh

J. For. Sci., 2009, 55(4):177-183 | DOI: 10.17221/102/2008-JFS

The use of skidding machinery in logging operations causes destructive effects especially on soil but has many advantages such as extracting long and heavy logs, optimum use of useful logging time and absence of defect in wood production quality and thus an increase in the added value of wood. In this research compartment 40 of the second district of Nav-Asalem in northern Iran at an altitude of 1,050-1,450 m above sea level was chosen in order to assess the amount of displaced soil volume and depth of ruts due to the traffic of Timber Jack 450C rubber wheeled skidder along the skid trail. Therefore, the correlations between two independent variables, longitudinal slope and soil texture, with two dependent variables, displaced soil volume and average depth of rut, along the skid trail were examined after 20 passes of skidder machinery. The results of this research showed a significant difference between the longitudinal slope increase of skid trail and the amount of soil volume displaced (P < 0.001). However, there was no significant correlation between the mean rut depth and different classification of longitudinal slope along the skid trail. The highest measured rut depth was 22 cm and occurred in the slope class of more than 25%. There was no significant correlation between the amount of displaced soil volume and rut depth with changes in soil texture along the skid trail.

Quantity and distribution of fine root biomass in the intermediate stage of beech virgin forest Badínsky prales

P. Jaloviar, L. Bakošová, S. Kucbel, J. Vencurik

J. For. Sci., 2009, 55(11):502-510 | DOI: 10.17221/31/2009-JFS

The fine root biomass represents 3,372 kg/ha in the intermediate stage of the beech virgin forest with different admixture of goat willow, where the vast majority of this biomass is located in the uppermost mineral soil layer 0-10 cm. The variability of the fine root biomass calculated from 35 sample points represents approximately 90% of the mean value and reaches the highest value within the humus layer. The total fine root length investigated in 10 cm thick soil layers decreases with increasing soil depth. A significant linear relationship between the fine root length (calculated per 1 cm thick soil layer and 1 m2 of stand area) and the soil depth was confirmed, although the correlation is rather weak. The number of root tips decreases with increasing soil depth faster than the root length. As the number of tips per 1 cm of root length remains in the finest diameter class without significant changes, the reason is above all a decreased proportion of the finest root class (diameter up to 0.5 mm) from the total fine root length within the particular soil layer.

The current demand for the insurability of liability for damage to the natural environment

E. Vávrová

Agric. Econ. - Czech, 2009, 55(1):33-39 | DOI: 10.17221/2505-AGRICECON

Since 2004, the basic document which has governed liability for damage to the natural environment in the European Union is the Environmental Liability Directive No. 2004/35/EC, as amended by the subsequent regulation No. 2006/21/EC. The main purpose of the legislation was to ensure that the entity responsible for the damage pays all costs for rectifying its consequences. If it concerns damage to natural environment, the operator must undertake measures for rehabilitation, replacement and regeneration of the damaged natural resources. The primary replacement, which returns the damaged natural resources to their original state, may be differentiated from complementary replacement as compensation in the case in which the primary replacement has not provided an adequate reparation, and finally compensatory replacement - compensation for the temporary loss of natural conditions. This paper aims at an analysis of the possible means for eliminating risks due to the liability for environmental damage caused by the actions of an operator whose activities potentially threaten natural environment and may cause the biodiversity damage. Risks are assessed with regard to the risk insurability criteria for potential damage to the natural environment. The importance of risk management is stressed in the sophisticated form known as the Enterprise Risk Management. Risk management is becoming increasingly important as a part of the Solvency II concept, currently in preparation, whose first and second pillars accentuate risk management in financial institutions and the consistent quantification of the obvious, hidden and potential risks.

Ecological requirements of some ant species of the genus Formica (Hymenoptera, Formicidae) in spruce forests

A. Véle, J. Holuša, J. Frouz

J. For. Sci., 2009, 55(1):32-40 | DOI: 10.17221/56/2008-JFS

Five types of stand stages (clearings-samplings, plantations, thinnings, thickets, and mature forests) of spruce forests were examined at the foothills of the Jizerské hory Mts. in summer 2005 and 2006. The presence of ants was surveyed by catching them into pitfall traps and observing on baits. Higher numbers of Formica fusca ants were found in clearings-samplings and in plantations. Their activity was higher at the soil and air temperature of 20-30°C. The peak of activity was observed in July. Most specimens were trapped at lighter habitats and in the sites with more than 50% herbaceous and gramineous vegetation cover. F. pratensis was trapped in plantations and thickets. It was active at the soil temperatures 12-21°C and air temperatures 16-25°C. It occurred both in dark and light areas. F. sanguinea most commonly occurred in thinnings. This species was the most active at the soil temperature 20-30°C. Its activity depending on air temperature grew almost linearly. It occurred both in dark and in light stand stages with at least 60% vegetation cover. F. truncorum was observed only in thinnings. The activity of F. truncorum was the highest at the air and soil temperatures 15-25°C. The peak of activity was recorded in July. It was observed only in stands with the quantity of incident radiation 1,030 lx and with 20-80% of undergrowth cover.

Mobilisation of arsenic in soils and in rice (Oryza sativa L.) plants affected by organic matter and zinc application in irrigation water contaminated with arsenic

D.K. Das, P. Sur, K. Das

Plant Soil Environ., 2008, 54(1):30-37 | DOI: 10.17221/2778-PSE

The experiments were conducted to study the effects of arsenic-contaminated irrigation water, zinc and organic matter on the mobilization of arsenic in an Aeric Endoaquept in relation to rice (cv. IET 4786). The results show that the amount of extractable arsenic increased with the progress of submergence decreased with zinc application. The magnitude of such decrease varied with the Zn amount, being greater (0.70 to 1.08 mg/kg) in the treatment where zinc was applied at the rate of 20 mg/kg. With regards to organic matter application, the arsenic content in soil markedly decreased, especially with farmyard manure application. The results of the greenhouse experiment with exposure of graded doses of arsenic to rice suggest that the upper toxic limit of arsenic in soil was 10 mg/kg for rice. The results of the field experiment show that the grain yield of continuous flooding (4.84 t/ha) and intermittent flooding up to 40 days after transplanting followed by continuous flooding (4.83 t/ha) with the application of ZnSO4 at the rate of 25 kg/ha did not vary significantly. The lowest grain yield (3.65 t/ha) was recorded in the treatment where the intermittent flooding was maintained throughout the growth period without the application of zinc. The amount of arsenic was, however, much lower in the treatment where intermittent flooding was maintained throughout the growing period combined with zinc sulphate application.

Effect of zinc foliar application on grain yield of maize and its yielding compone

J. Potarzycki, W. Grzebisz

Plant Soil Environ., 2009, 55(12):519-527 | DOI: 10.17221/95/2009-PSE

Actual yields of maize harvested by farmers are at level much below attainable yield potential of currently cultivated varieties. Among many growth factors zinc was recognized as one of main limiting factors of maize crop growth and yielding. This hypothesis has been verified within a three-year field study, where zinc fertilizer was applied to maize plants at the 5th leaf stage. Maize crop responded significantly to zinc foliar application in two of three years of study. The optimal rate of zinc foliar spray for achieving significant grain yield response was in the range from 1.0 to 1.5 kg Zn/ha. Grain yield increase was circa 18% (mean of three years) as compared to the treatment fertilized only with NPK. Plants fertilized with 1.0 kg Zn/ha significantly increased both total N uptake and grain yield. Yield forming effect of zinc fertilizer revealed via improvement of yield structure elements. The number of kernels per plant showed the highest response (+17.8% as compared to the NPK plot) and simultaneously the highest dependence on N uptake (R2 = 0.79). For this particular zinc treatment, however, the length of cob can also be applied as a component of yield structure significantly shaping the final grain yield.

Evaluating the shelterwood harvesting system after 25 years in a beech Fagus orientalis Lipsky) forest in Iran

M. R. Pourmajidian, N. E. Malakshah, A. Fallah, A. Parsakhoo

J. For. Sci., 2009, 55(6):270-278 | DOI: 10.17221/77/2008-JFS

Beech (Fagus orientalis Lipsky) is the most industrial commercial tree species among more than 80 broadleaved trees and shrubs in Hyrcanian forests. In this study some of the silvicultural properties of beech were studied under a shelterwood cutting system in a regeneration unit of 25 years old stand in Sangdeh forests of Iran. Tree height, diameter, canopy cover, variety of species, frequency at different stages of growth (seedling, sapling, thicket and pole) and tree density at juvenile phase were recorded in 431 circular 1,000 m2 sample plots before and after shelterwood cutting. Results indicated that tree density in the diameter at breast height (dbh) class of < 20 cm increased during shelterwood cutting. Canopy cover of regeneration unit was 78.5% in 1957, while in 2000 and after the shelterwood cutting it reached 59%. Growing stages of regeneration were 14% sapling, 21% thicket, 24% small pole and 41% pole. The shelterwood method has not been very successful in our study area due to a number of technical and potential problems.

The effects of fosetyl-Al application on morphology and viability of Lycopersicon esculentum Mill. pollen

I. Öztürk Çali

Plant Soil Environ., 2008, 54(8):336-340 | DOI: 10.17221/414-PSE

In the present study, the effects of fungicide Aliette WG 800 [80% fosetyl-Al (aluminium tris-o-ethyl phosphonate)], widely used against Phytophtora infestans on tomatoes grown in greenhouse in Turkey, were studied on the morphology and viability of tomato (Lycopersicon esculentum Mill.) pollens. The fungicide was applied to tomatoes grown in greenhouse at recommended dosage (200 g/100 l water) and at double the recommended dosage (400 g/100 l water). The fungicide caused changes in the morphological structures of tomato pollens. Some pollen morphological structures that are not observed in the control group were encountered in the pollens in equatorial view and in polar view at 200 g/100 l treated groups. On the other hand, pollen viability level decreased as the dosage increased. Especially, non-viable pollen types such as wrinkled pollen or pollen with abnormal shape were encountered in the fungicide groups. It was expected that the pollen fertility as well as yield would decrease in future.

Cadmium balance in soils under different fertilization managements including sewage sludge application

K. Čásová, J. Černý, J. Száková, J. Balík, P. Tlustoš

Plant Soil Environ., 2009, 55(8):353-361 | DOI: 10.17221/142/2009-PSE

Simple balance of Cd input by different treatments and removal by agricultural crops was investigated in an ongoing precise long-term field experiment with application of sewage sludge (SS), farmyard manure (FYM), and mineral fertilizers (NPK). Potatoes, wheat and barley were grown in a rotation at 4 experimental sites of the Czech Republic with the aim to assess the risk of Cd accumulation in soil and plants under different soil and climate conditions. The results showed significant differences in Cd content of the input materials used, and in Cd inputs to soils under different fertilization managements. Three applications of sewage sludge during 1996-2005 resulted in total addition of 110 g Cd/ha into soil, which was by one order of magnitude higher than Cd addition in FYM or NPK treatments. From the total amount of sludge-borne Cd, only small portion was removed by harvests of crops (approximately 3.5%). Soil conditions significantly affected Cd input-removal balance. The highest Cd removals were obtained on soils with the lowest pH. The highest Cd removal was achieved by potato tubers followed by wheat and barley plants. The results showed that the risk of Cd accumulation in soils is high, especially with repeated sludge applications.

Development of species composition in long term simulations with an individual-tree growth simulator

M. Huber, H. Sterba

J. For. Sci., 2009, 55(5):194-200 | DOI: 10.17221/14/2009-JFS

The spruce-fir-beech dominated forest stands in Litschau in the Austrian part of the Bohemian Massif were converted by former forest management practices into pure Norway spruce stands and are now discussed to be reconverted into the potential natural vegetation type. The targeted potential natural vegetation type is usually defined by experts in vegetation sciences. Because meanwhile individual-tree growth simulators are a well acknowledged tool for predicting future forest stand development, in this study we investigate if PROGNAUS can also be used to predict the redevelopment of managed forest ecosystems into natural forest ecosystems regarding species composition. The development of 23 stands in Litschau has been simulated over 1,000 years under the "no-management" option. Generally, the simulated species distribution agrees quite well with the expectations of the potential natural vegetation type. However, the predicted amounts of silver fir and maple species are lower than expected, which probably is due to browsing and management effects represented in the parameterization data for PROGNAUS.

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