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The paper deals with research on the biomass production of fruiting bodies of macromycetes in a submountain beech stand in dependence on selected climatic variables. The study was carried out at the Ecological Experimental Site (EES) Kremnické vrchy (Central Slovakia) in 2003 and 2004. The biomass production of sporocarps on the EES plots in the two study years was different (5.81 kg/ha of fresh biomass of sporocarps in 2003 and 39.95 kg/ha in 2004) due to better ecological and climatic conditions and higher abundance of sporocarps in 2004. It is necessary to mention that these values reflect the overall status of mycocoenoses on the plot. Unfavourable microclimate conditions and poor species composition of beech monocultures can be considered to be the main factors adversely influencing mycocoenoses in forest stands of the kind.

Results obtained during 14 years of the experiment are presented. Extreme site conditions are determined by: 8^th vegetation altitudinal zone, podzolic soil and hard climate - average annual temperature 4°C, average annual precipitation around 1,200 mm. Effects of surface experimental liming were studied on immission clear-cuts in long time period, study area is located on the Velká Deštná locality on the main Orlické hory Mts. range. Research plots were established and the basic survey was done in spring of 1988, studies of liming effects were performed in the period 1987-2002. On particular plots, 0, 1,308, 2,826, 3,924 and 8,478 kg/ha of fine limestone (grain size under 1 mm) was distributed by hands on the soil surface, as an application of 3 and 9 t/ha of "fine" and "coarse" material (together 5 variants including the control one). Results are available for the forestry practice, research has to continue in the future - potential of negative liming impacts is topical here, consisting in humus mineralization and nutrients losses. Maximum effects on the soil reaction were observed in 8-10 years after limestone application at the soil surface (F - horizon) and in the period 10-15 years lower (H, A - horizons). Base saturation dynamics shows the time delay 2-4 years following pH values. For the site protection, efficient forest stands are vitally important of pioneer as well as climax species.

Net N mineralization rate (NMR), net N consumption rate (NCR), microbial biomass carbon (MBC) and nitrogen (MBN), potentially mineralizable N (PMN) and mineral N (N-NH⁺₄ and N-NO^-₃) were measured in paddy soil at five growth stages of rice to determine the effect of long-term fertilization in subtropical China. The studied long-term treatments included CK (no fertilization), N, NP, NPK and NPK + OM (NPK plus organic manure). The NPK + OM treatment gave the highest values of the measured variables among all treatments. There was no significant difference in other treatments except for mineral N and PMN at early growth stages. All these variables were generally highest at transplanting stage as two thirds of fertilization was applied as basal fertilizers and the rice uptake was low. Then they decreased or leveled off with the rice growth stages except for MN in all treatments. Stepwise regression revealed that NMR was significantly correlated with MBC and N-NH⁺₄ (R² = 0.954, P < 0.01) at all rice growth stages. So, mineral plus manure fertilizer application and more mineral fertilizer as topdressing were recommended in subtropical paddy soil.

The paper analyses the development of agrarian foreign trade of the EC/EU states in the period 1961-2006. The aim of the analysis is to evaluate the influence of the EC/EU member base enlargement on the development of the value and territorial structure of the Community agrarian trade. Additionally, the paper analyses the impacts of the accession of the particular countries on their own and the total agrarian trade of the Community with the aim to clarify the development trends which preceded the accession to the EC/EU and which subsequently appear after the accession of the given state to the Community. Development trends recorded in the case of all joined countries in the period 1973-2006 are compared and in the final part of the paper, the impacts of the enlargement of the EC/EU on the development of internal (intra) and external (extra) trade are summarised.

In this work preliminary studies on application of immunochromatographic method to detection of pesticides in food samples, in particular fruit juices, are presented. The aim was to develop immunochromatographic technique on a porous membrane for rapid detection of the pesticides thiabendazole and methiocarb in fruit juices. For detection colloidal carbon conjugated with secondary antibody was used. The tests were evaluated visually. Our results show that in the fruit juices samples examined the detection limit for thiabendazole covered the MRL (maximum residue limit) for food of plant origin established by the legislative and for methiocarb the method has to be further optimised in order to decrease the detection limit below the MRL.

: The study evaluates production parameters (height, diameter at breast height, volume) of Douglas fir (Pseudotsuga menziesii [Mirb.] Franco) at mesotrophic sites of the Křtiny Training Forest Enterprise in mature stands. In total, 29 mixed stands were assessed with the registered proportion of Douglas fir at an age of 85 to 136 years. Comparing the 10 largest Douglas firs with the 10 largest spruces or larches higher, and as a rule markedly higher, production potential of introduced Douglas fir was found in all assessed stands. There were also groups of trees where the volume of Douglas fir was twice to 3 times higher than the volume of spruce or larch (see Tabs. 5 to 10). For example, in stand 177B11, the mean volume of 9.12 m³ was recorded in the 10 largest Douglas fir trees but the volume of spruce reached only 3.17 m³ and the volume of larch was 3.70 m³. Differences in mensurational parameters of Douglas fir found on the one hand and of Norway spruce (Picea abies [L.] Karst.) or European larch (Larix decidua Mill.) on the other hand compared by ANOVA tests were statistically highly significant. Annual ring analyses have shown that at present the volume increment of particular Douglas fir trees ranges from 0.12 to 0.16 m³ per year in mature stands (i.e. about 1.5 m³ every 10 years).

Soils were sampled from the plots with four variants of fertilisation: Nil - without fertilisation, NPK - mineral fertilisation, FYM - farmyard manure, FYM + NPK - farmyard manure with mineral fertilisation, and two variants of crop rotation: field IV - classical 9-year crop rotation, field B - 2-year rotation of alternative growing. Determination of urease, CFU of Azotobacter spp. and potential nitrogenase activity was conducted during the period 1999-2004. The urease activity was positively affected by manure fertilisation (FYM) and by the combination of FYM + NPK. The statistically significantly highest counts of Azotobacter spp. and the highest nitrogenase activity were determined on field B in variants FYM and FYM + NPK. The results show that there was a higher amount of accessible nitrogen present on field IV than on field B. This might explain the lower counts of Azotobacter spp. and therefore the lower nitrogenase activity. According to our results, activity of urease, CFU of Azotobacter spp. and potential nitrogenase activity are very closely connected with N inputs.

The objective of this study was to evaluate the influence of organic (cattle manure) and inorganic fertilizers [composite NPK (15:15:15)] and natural zeolites on soil properties, vegetative growth and yield of apple plants grown on vertisol under Cacak conditions (Western Serbia). The results showed that the combined fertilization induced a decrease in acidity, an increase in humus content, a partial increase in total nitrogen (NTOT), and, primarily, a rise in available phosphorus (P) and potassium (K) levels. A highly significant (P < 0.01) interactive effect of the apple cultivars and nutrients on one-year-old shoot length and trunk cross-sectional area (TCSA) and a significant effect (P < 0.05) on yield per tree and yield per hectare were determined.

Lucerne (Medicago sativa L. var. Palava), harvested at four successive dates over a 30-day period, was evaluated for chemical composition (dry matter, organic matter, crude protein, ether extract, crude fibre, nitrogen-free extract, neutral detergent fibre, acid detergent fibre, acid detergent lignin), amino acid contents and intestinal digestibility in dairy cows. Dry matter (r = 0.78), organic matter (r = 0.95), crude fibre (r = 0.91), neutral detergent fibre (r = 0.94), acid detergent fibre (r = 0.79) and acid detergent lignin (r = 0.48) presented positive linear correlation coefficients (r) with growth stage, whereas crude protein (r = -0.96), ether extract (r = -0.86) and nitrogen-free extract (r = -0.70) showed negative relationships. Total essential amino acid content decreased (r = -0.94) from 84.1 to 55.3 g/kg of dry matter with maturity, with r-values higher than -0.90 obtained between growth stage and contents of lysine, methionine, threonine and valine. With the exception of tyrosine (r = -0.68), r-values between growth stage and individual non-essential amino acids were all higher than -0.90. Total amino acid (r = -0.98) and nitrogen (r = -0.99) contents presented comparable tendencies with successive sampling times. Whereas no definite trends were detected for the amino acid composition of rumen incubated (16 hours) lucerne samples, the intestinal digestibility of total essential (r = -0.78), total non-essential (r = -0.58) and total (r = -0.69) amino acids as well as nitrogen (r = -0.99) decreased with growth. However, due to a small sample size (n = 4), most linear relationships between constituents and growth stage were insignificant. It can be concluded that, although limited in the sample size, this report presents information on the decrease in amino acid contents and intestinal amino acid digestibility as growth proceeds in lucerne (var. Palava) produced in the Czech Republic, which could be utilized in the feeding of ruminants.

Sustainable land management requires that water and matter (nutrients and base cations) are efficiently recycled within ecosystems so that irreversible losses of matter from topsoils are minimised. Matter losses are connected to water flow. The division of water into evapotranspiration that is loss-free, and seepage to groundwater or surface water flow that both carry material losses, is decisive in determining total losses of dissolved matter in a given catchment. Investigations of areal matter losses confirmed the instrumental role of vegetation cover. Areal matter losses measured in agricultural catchments in Germany were on average between 1-1.5 tons of dissolved matter per ha per year, i.e. some 50 to 100 times higher than those from unmanaged land in a virgin forest. Such high losses continuously reduce soil fertility and can hardly be compensated by fertilisation. Some suggestions on how to achieve sustainable management of agricultural land and maintain high soil fertility are presented - the priority is to close water and matter cycles through the incorporation of more natural vegetation cover into our landscapes and to restore the energy-dissipative properties of ecosystems.

: Clostridium difficile is considered an important uncontrolled cause of neonatal diarrhea. Also, the presence of bacteria in the feces of the animal could represent a zoonosic risk for the contamination of meat products. Therefore, it is necessary to have procedures available for the early detection of C. difficile in animals. The current study describes a new semi-automated procedure for the recovery of C. difficile DNA from pig feces and subsequent amplification by polymerase chain reaction (PCR) of three different sequences: the triose phosphate isomerase gene tpi, specific for this bacterial species, and the tcdA and tcdB genes, which code for the A and B toxins of C. difficile, respectively. Twenty-two fecal samples microbiologically positive for C. difficile were used. The tpi and tcdA genes were amplified in all of them. The internal fragment of tcdB was detected from 21 of these extracts; the negative sample gave a positive result when a different primer pair was used. None of the 10 DNA extracts obtained from culture-negative samples gave a positive result. The method presented in this article eliminates the interference caused by the possible presence of PCR inhibitors. To the authors' knowledge, this is the first description of a PCR procedure for detection of C. difficile DNA from domestic animal feces.

The study deals with the monitoring of dissolved organic carbon (DOC) concentrations in seepage water sampled from differently managed forest plots in the Drahanská vrchovina Upland. Simultaneously, the input of DOC in precipitation and throughfall is evaluated. Preliminary results show higher mobility level of carbon substances in forest soil in a pure spruce stand compared to mixed stand or a pure beech stand. DOC can be one of suitable characteristics to evaluate the conversion effectiveness of spruce monocultures.

Plant root and shoot dry weight, leaf relative water content (LRWC) and chlorophyll content were reduced by 30%, 21%, 15%, 34%, respectively, at 40mM NaCl as compared to non-salt stress conditions. However, membrane permeability (MP) of plant increased (85.0%) with increasing salinity. Foliar nutrient application (FNA) alleviated deleterious effects of salinity stress on growth and this effect was statistically significant. The highest alleviation effect of FNA at 40mM salinity stress was observed in the case of 10mM foliar KNO₃ and Ca(NO₃)₂ application, resulting in increase in plant root dry weight (50%), shoot dry weight (50%), LRWC (8.2%) and MP decrease (27.4%) at 40mM NaCl. Phosphorus, Fe and Zn contents in shoots and roots of plants also increased with FNA treatments, but they were still much lower than those of non-salt stress treatment. Sulphur, P, Fe and Zn contents of shoots reached similar values as in non-salt stress treatment when KNO₃ was applied, whereas Fe, Mn, Zn, and Cu contents of roots reached the values of non-salt stress treatment when Ca(NO₃)₂ was applied.

The basis of the biogas production in agriculture is the processing of waste agricultural products (particularly excrements of farm animals but also phytomass). Different but rather similar is the biogas production from biologically degradable municipal waste (BDMW) and biologically degradable industrial waste (BDIW) coming mainly from food industry. The processing of these wastes in agricultural biogas stations could significantly improve their economy. It is necessary to note that all these biogas stations differ from the wastewater cleaning plants where municipal sludge water from public sewers is processed. The municipal sludge water processing to biogas by anaerobic fermentation is a classical technology introduced all over the world. At present, about 100 wastewater cleaning plants operate in the Czech Republic using regular sludge processing into biogas. Electricity produced is utilised mainly for the needs of own operation of waste water treatment plant (WWTP), partly it is sold into public power net. The heat energy is used for heating in the process and its surplus is utilised for operational and administrative facilities. Usually, the heat and electricity quantities produced do not cover the wastewater cleaning plant operation. Agricultural biogas stations and biogas stations for BDMW processing provide considerably higher gas yields because they work with higher dry matter contents in substratum, i.e. 8-12% (compared with waste water treatment plants - 2-6%), and are able to produce high gas surpluses for following applications. Frequently discussed issue are the processing of slaughter waste and grass (or public green areas at biogas stations).

Fog and rime water samples were collected at the meteorological observatory Milešovka in February and June 2006. In the samples, the soluble and insoluble pollutant concentrations were evaluated separately and the differences between the fog and rime water samples were studied. The comparison of the fog and rime water samples indicates that the mean soluble component concentrations in the air appear to be higher during the rime events than during the fog events at Milešovka. We recorded a larger mean particle size of the insoluble compounds in the fog water samples than in those of rime water. Some elements contained in the insoluble particles like Ca, Cl, C, Cu, Ag, were present largely in fog whole others, like Fe, Al, Si, Ti, prevailed in rime. In addition to the overall evaluation, the backward air trajectories were determined for each fog/rime event and the concentrations are presented as depending on the direction of the air particle transfer.

The investigation of foliage biomass development including LAI and the growth of spruce and beech stands in the juvenile stage (age 1 to 21 years) represents a special complementary study to long-term research of water balance components on the experimental forest hydrology area Deštné Mountainside. The experiment is located in the Orlické hory Mts. at the altitude of 900 m on a clear-felled area. In 1982 the spruce plantation was established at 1.5 ´ 1.5 m spacing (4,600 plants/ha) and the beech plantation at 1.0 ´ 1.0 m (10,000 plants/ha). According to tending programs applicable to forest stands in the Czech Republic, two improvement fellings were carried out (1995 and 2001) in spruce and none in beech. In 2002, some 1,550 spruce trees/ha (mean height 10.1 m) and 7,440 beech trees/ha (mean height 4.8 m) were recorded. At the end of the first vegetation season in 1982, the dry matter (DM) of foliage in spruce and beech amounted to 35 and 70 kg/ha, respectively. Five years later (1987), these values increased to 770 and 360 kg/ha in spruce and beech, respectively. At a stand age of 21 years, foliage DM was determined to be 11,940 kg/ha for spruce and 3,050 kg/ha for beech. At the same time, the leaf-area index (LAI) was calculated to be 5.55 and 5.94 in spruce and beech, respectively. The method of foliage biomass quantification, based on the determination of foliage DM of mean sample trees and stand density, enabled to acquire complementary data usable in long-term research of the water regime of spruce and beech and simultaneously to provide information on the potential of biomass production and LAI value of both main commercial species in mountain forests of the Czech Republic.

The mycological conditions on study plots established in forests growing on former agricultural farm lands were studied. In young spruce stand (8-10 years) reduced and unstable spectrum of macromycetes was found. After approximately 50 years of forest growth the situation became stable and spectrum of macromycetes together with development of mycorrhizal status were similar to a situation found in stands on forest soils. Slightly increased occurrence of saproparasitic species of fungi (e.g. Heterobasidion annosum at others) was observed in older growths.

The effects of different concentrations of copper (0-800 μmol) on growth, protein contents, peroxidase (POD), catalase (CAT), superoxide dismutase (SOD), and phenylalanine ammonia-lyase (PAL) in Jatropha curcas L. seedlings were assessed by means of pot experiments. Results suggested that increased copper concentrations lead to decreased shoot elongation and seedling biomass. Protein content in the leaves and roots reached their highest levels at the copper concentrations of 400 μmol, while the highest protein content in the stem was observed at 800 μmol copper. POD activity in leaves and stems was unaffected at low copper concentrations, but showed a considerable variation at high copper concentrations. In roots, the highest POD activity was observed at 200 μmol copper. Under copper stress, SOD activity in leaves increased concomitantly with increasing copper up to 400 μmol, and SOD activity in stems and roots showed a slight increase. Catalase activity significantly elevated in leaves and roots but showed no significant changes in stems of the seedlings exposed to copper. A gradual increase of PAL activity in leaves and roots at the copper concentration of 400 and 200 μmol was observed, while PAL activity remained unchanged in stems.

The CULTAN (Controlled Uptake Long Term Ammonium Nutrition) system is based on one-time injection of the whole dose of nitrogen required for the vegetation period. The effect of this method on yield and grain quality of winter wheat was observed in a 2-year small-plot trial at 4 different experimental sites in the Czech Republic. The experiment comprised two treatments with the total amount of nitrogen applied during fertilization of 150 kg N/ha. At the CULTAN treatment the whole dose was applied all at once using the GFI 3A injection machine (Maschinen und Antriebstechnik GmbH Güstrow), whereas at the control treatment, the dose was divided into three applications. The average grain yield of winter wheat in 2007 was 9.56 t/ha (control) and 8.78 t/ha (CULTAN); in 2008 it was 9.91 t/ha (control) and 9.63 t/ha (CULTAN). The differences in 2008 were not statistically significant. The contents of nitrogen and gluten were significantly lower at CULTAN treatment in both years. The values of falling number, Zeleny test and bulk density were generally similar at both treatments.

The perception of exogenous chemical substances, olfactory navigation and the use of the olfactory sense by birds to search for food are reviewed. Many results suggest that the olfactory sense is one of the important components of the navigation system in birds. The olfactory mechanisms used by homing pigeons to navigate homeward from distant sites have been well studied. The scent of potential food, carcasses, is a positive attracting percept for Vultures. Procellariiform seabirds (petrels, albatrosses and shearwaters) are able to localize food sources by using their olfactory sense. Procellariforms are sensitive to scented compounds associated with their primary prey: krill-related odors (pyrazines and trimethylamine), odors associated with phytoplankton (dimethyl sulfide - DMS) and ammonia. Anting is a specific type of behavior of over 200 bird species. Birds probably use anting to control ectoparasites, inhibit the growth of fungi or bacteria, to soothe skin irritated during the molting period, and to remove toxic formic acid from ants prior to their consumption. Insectivorous birds react to insect malodorous substances, produced by insect groups as a chemical defense against predators.

Vitamin C (later noted VITC) and polyphenols (later noted PP) were regarded as main nutritional markers in the transformation process of stewed apples after an in situ measurement campaign at two leading French industrials on that matter. Experiments on pilots with the CTCPA of Avignon made it possible to create a small experimental data base whose treatment is the core of this article. The objective of this work is to check if the experimental data collected at the CTCPA facility can be represented by a single model of 2 separate first order reactions, with or without Arrhenius, under varying processing temperatures.

In an experiment with 45 neonatal male Holstein calves, effects of yeast cultures Yea-Sacc^® 1026 (SC) containing Saccharomyces cerevisiae (strain 1026) and Vitex (KF) containing Kluyveromyces fragilis (strain Jürgensen) on rumen fermentation characteristics were determined. From day 4 to day 56 of age, the calves were allocated to one of the three dietary treatments (Control, SC, and KF) of 15 animals each, placed in individual pens, and fed 4 l of whole milk twice daily and a basal concentrate mixture ad libitum as calf starter feeds. The control treatment was not supplemented with yeast culture. The yeast culture supplements Yea-Sacc^® 1026 and Vitex were top-dressed at 10 g/calf daily on the basal concentrate mixture of treatments SC and KF, respectively. At the end of the experiment (day 56), all calves were slaughtered and the rumen fluid was analysed. The administration of yeast cultures Yea-Sacc^®026 and Vitex to calves did not affect final body weight (BW), BW gain, dry matter intake, feed conversion ratio, ruminal pH, lactic acid concentration and the molar proportion of propionic acid, but it decreased (P < 0.05) the total volatile fatty acid concentration and the molar proportion of butyric acid, and increased (P < 0.05) the molar proportion of acetic acid and the acetate to propionate ratio. In addition, the microbial cellulolytic activity was higher in calves that received both yeast cultures compared to the control treatment. The results of this study suggest that the ruminal fermentation was more stable in calves receiving yeast culture supplements.

The study is a follow-up of the production potential of Douglas fir in mesotrophic sites of the Křtiny Training Forest Enterprise (TFE) (Journal of Forest Science, No. 7, 2008). Production parameters (height, dbh, volume) of Douglas fir are also evaluated, but in acid sites of the Hůrky Training Forest District, Secondary Forestry School in Písek in mature stands. In total, 17 mixed stands with the proportion of Douglas fir aged 88 to 121 years were assessed. Comparing 10 Douglas fir trees with 10 Norway spruce, Scots pine or European larch trees of the largest volume, higher and generally markedly higher production potential of the introduced Douglas fir was always found in all assessed stands. Groups where the volume of Douglas fir trees was two to three times higher than the volume of spruce, pine or larch were not an exception. For example, in stand 22B10, the mean volume of the 10 largest Douglas fir trees was 6.30 m³ but the volume of spruce trees was only 1.93 m³ and the volume of larch trees 2.25 m³. Differences between the mensurational parameters of Douglas fir and spruce (or larch) assessed by the ANOVA test were statistically highly significant. At present (based on annual ring analyses), the volume increment of particular Douglas fir trees ranges at level of 0.06 to 0.10 m³/year (i.e. about 0.6 m³ to 1.0 m³ per 10 years) in mature stands.

Chlorophyll a fluorescence measurements were carried out on two barley (Hordeum vulgare L.) cultivars Arabi Abiad and Arabi Aswad at 8 and 14 days after emergence to identify their early tolerance mechanism for heavy metals (25 and 50μM of cadmium and lead). Transient fluorescence curves (OJIP curves) and energy flux models showed different specific reactions of photosystem II (PSII) of each cultivar to each type of stress. After 7 days of lead stress application plants of cv. A. Aswad showed weaker I and P peaks on the OJIP curve than control plants, and the appearance of a new K step; parameters of phenomenological energy fluxes for cv. A. Abiad were similar to those for control plants and only some silent reaction centers appeared. Generally, parameters of energy fluxes within PSII were directly shifted shortly (24 h) after the application of both heavy metals, especially in the case of plants grown under cadmium treatment. This suggests that these parameters could be good indicators for monitoring of these two pollutants in the environment at early stages of plant development.

Pot experiments were conducted to determine the best time for application of (ethylenediaminetetraacetic acid) EDTA and sheep manure extract (SME) in phytoremediation of a contaminated soil by Helianthus annuus. The plant was grown in a mine calcareous soil treated with increasing concentrations of EDTA or SME in 30 and 10 days before sowing (T1 and T2) and 10 and 30 days after sowing (T3 and T4). The best time for EDTA application was T4. The EDTA application before seed germination significantly reduced sunflower seedling emergence and dry weight. Soil available Pb and lead concentrations in plant organs increased with EDTA concentration but the actual amount of phytoextracted Pb decreased at high EDTA concentrations significantly, due to severe growth depression. SME application after sowing can increase plant dry weight and Pb concentration in the soil solution, enhancing the accumulated metal concentrations in shoots and roots. However the results showed that the most efficient treatments for Pb phytoextraction by sunflower are applications of 0.5 and 2 g EDTA/kg soil at T3 and T4, respectively.

Soil micromorphology was applied to specify flow domains in different soils and to select a suitable numerical model for simulation of water flow and herbicide transport. Pore structure detected on soil micromorphological images represented in all cases domains of prevailing water flow and solute transport. Depending on pore configuration and boundary conditions either water immobilization or preferential flow was observed and simulated. The benefits and limitations of the soil micromorphology imaging are discussed and compared with the more often used X-ray computer tomography, magnetic resonance imaging and dye tracer imaging.

The possibility of peat replacement with crushed water absorbent rockwool in growing substrates in the amount of 35% vol. was verified in the experiment with perennials in containers. Three types of substrates, i.e. peat, and two mixtures of peat with alternative components - green waste compost (25% vol.) or composted spruce bark (40% vol.) were compared. A sand box in the range of -0.5 to -10 kPa was used to determine retention curves and other physical properties of the components and substrates. The addition of rockwool to the peat substrate increased content of air and easy available water, the plant growth was not affected. Plants grown in substrates with alternative organic components were smaller in comparison to peat substrate. The growth of perennials significantly decreased, mainly in substrates with bark, but the plants had good market value. The addition of rockwool to these substrates had no significant effect on the growth. Crushed rockwool in the amount of 35% vol. can replace peat in peat substrates and in mixtures with alternative components.

Soil samples (from Czech and German long-term field experiments) were used to estimate different soil phosphorus (P) fractions. More than 200 topsoil (0-30 cm) samples from different fertilizing treatments were taken. These were analyzed for P in soil solution (P_CaCl2) [0.01M CaCl₂ extract], exchangeable sorbed P (P_ex) [anion exchange (AE) membranes] and bioavailable P [Doppel-Lactat and Mehlich 3 (P_DL and P_M3)]. Other fractions analyzed were total inorganic (P_in), total (P_M-tot) and organic (P_org) P [fractionation after Marks], P sorbed on Fe and Al (P_FeAl) [fractionation after Schwertmann] and residual P (P_ar) [aqua regia extract]. Comparison of medians appeared to be better for evaluating extraction abilities. Phosphorus fractions were in the following order: (P_ar = 100%); P_CaCl2 (0.2%) < P_ex (9%) < P_DL (10%) < P_M3 (16%) < P_in (24%) < P_org (37%) < P_FeAl (55%) < P_M-tot (59%). Low amounts of P_in, P_org and P_M-tot did not verify the applicability of the Marks' fractionation for the set of studied soils. Close correlations at P ≤ 0.001 were found for all methods for estimating the fractions of bioavailable phosphates (P_CaCl2, P_ex, P_DL and P_M3). Statistically significant relations were observed between P_in with P_ar, P_M-tot and P_FeAl.