Fulltext search in archive

Significant quantities of Cd have been added to soils globally due to various anthropogenic activities, posing a serious threat to safe food production and human health. Rhizosphere, as an important interface of soil and plant, plays a significant role in the agro-environmental system. This article presents a review of relationship between root excretion and microorganisms and plant resistance to Cd toxicity and possible mechanisms. Root exudates markedly altered in species and quantity under Cd stress. Root exudates can affect Cd absorption by plants through changing the physical and chemical characteristics of rhizospheres. The influence of root exudates on Cd bioavailability and toxicity may include modifying the rhizosphere pH and Eh, chelating/complexing and depositing with Cd ions, and altering the community construction, the numbers and activities of rhizospheric microbes. In this paper, the methods to reduce the transfer of Cd in soil-plant system by adjusting rhizosphere environment are discussed, and some aspects are also proposed that should be emphasized in the future research work.

In order to study the characteristics of element values in the cell of plants and soils and their relationships that would help to evaluate the biogeochemical effect of soil on the element contents in the cells of plants in the same environment of Southwestern China, the soil samples were collected for analysis and the weight and atom percentage of elements (WT% and AT%) in the leaves of two different species of Flos Lonicerae were analyzed by the electron probe (EDX-9100). The results of soil analysis show that the nutrient element contents in the soil are determined by the liable content of elements, which were arranged as: Ca > Mg > Cu > Mn > K > Na > P > B > SiO₂ > Zn > Fe, even though the total element values in soil of different horizons were arranged as: SiO₂ > Fe > Ca > Mg > K > Na > Mn > P > Zn > B > Cu. It indicates that karst environment is composed of soluble calcium-rich rock and soil scarcity. Moreover, the migratory velocity and availability of elements are also determined by their coefficient variability. According to statistical results, Ca, Mn and P in the soil have high coefficient variability, reflecting its background of karst soil. Based on the electron probe, it is shown that the content of Ca is higher while Mg is the lowest in the cell of two different species of Flos Lonicerae (r = -0.156, P < 0.05) and the content of P in the cell is inferior to Ca (r = 0.868, P < 0.01). By studying the relationship of soil and the plants, it can be seen that these results are probably caused by the characteristics of local biogeochemistry. Ca is mainly absorbed by plant with the help of transpiration and accumulated in the cell, and thus becomes a predominant element in the cell. The accumulation of Ca in cell of plant will affect the absorbency and the content of other elements in the cell of Flos Lonicerae, resulting in the different contents of other elements in the Flos Lonicerae through synergistic and antagonistic action, followed by the affected quality and officinal value of the Flos Lonicerae.

The present study was aimed at determining the origin, course and distribution of the celiac artery in eight adult red falcons, using a latex injection and dissection method. The celiac artery was ascertained to originate from the aorta at the level of the last 2-3 costae. The celiac artery was determined to split into two main branches, namely, left branch of the celiac artery and right branch of the celiac artery, in between the proventriculus and gizzard, and in the proximity of the lien. Prior to the indicated bifurcation, the celiac artery was observed to give off an esophageal artery and superior proventricular artery. In seven of the red falcons examined, splenic arteries, varying from two to four in number, were determined to spring from the celiac artery. Both the left and right hepatic arteries were ascertained to stem from the left branch of the celiac artery. The terminal branch of the left branch of the celiac artery, namely, the left gastric artery, was determined to have a fan-like distribution to the left surface of the gaster. The artery of the gall bladder was demonstrated to emanate from the left branch of the celiac artery in all of the red falcons examined, excluding one. The right branch of the celiac artery was determined to ramify into its terminal branches, namely, the right inferior gastric artery, ileocecal artery, pancreaticoduodenal artery, duodenojejunal artery and gastroduodenal artery, in the proximity of the pylorus which constitutes the gastro-duodenal passage.

Conservation of crops is based on ex situ collection into gene banks. Additionally, crop's wild relatives can be conserved in situ, and landraces and obsolete cultivars also can be conserved using the on-farm method. The definition and methodology of on-farm conservation is discussed. On-farm conservation has been set up in the Czech Republic as model examples in several institutions dealing with nature protection, education, cultural conservation, as well as by some private farmers. Problems, plus positive and negative experiences are presented. On-farm conservation in open-air-museums in the natur (skansens) as well as in the national parks, seem to be suitable ways forward for the Czech Republic.

: Nutrient digestibility and parameters of nutritive value for ruminants of two winter wheat (Triticum aestivum L.) cultivars were evaluated by means of an in vivo balance trial performed by the regression method on two groups of heifers with an increasing proportion of grain in DM (from 6 to 46%). Sulamit and Rapsodia, chosen on the basis of the in vitro test from a set of 25 cultivars (grown in 2002-2004) reached significant differences in DM fermentability in vitro (by 43.7-78.6 ml/g DM, P < 0.05). In vivo digestibility of crude protein, nitrogen-free extract, organic matter, parameters of N retention, energy concentrations (metabolisable energy, net energy for lactation and for fattening) and parameters in the PDI system (especially PDIE) increased along with the grain proportion in the diet. At the comparable proportion of grain in the ration the positive differences were significantly higher (P < 0.05) for Sulamit than Rapsodia.

In Europe, Rumex obtusifolius L. is the most problematic grassland weed species, especially under the conditions of organic farming. The aims of this study were (1) to investigate the effectiveness of repeated mechanical weeding of R. obtusifolius from the permanent sward, cut two or three times per year, by digging the plants out from 5 cm below the soil surface, and (2) to test the effect of nutrient availability on the effectiveness of mechanical weeding. In 2007, the manipulative experiment was established on permanent grassland infested by R. obtusifolius using the following fertilizer treatments: control, P, N, NP and NPK. Plants of R. obtusifolius were removed eight times during three vegetation seasons. No significant decrease in the density of R. obtusifolius was recorded after three vegetation seasons and density was not significantly affected by fertilizer treatment. The cover of R. obtusifolius decreased slightly, but significantly, over the study period from 7.5% to 4.5%. The cover of R. obtusifolius was only marginally affected by fertilizer treatment. Mechanical weeding by digging the plants out from 5 cm below the ground is not a sufficient method of control for R. obtusifolius in infested fertile grasslands, even when applied eight times during three vegetation seasons.

Each society wishes to create favourable living conditions for its members. Life quality criteria are formulated in different ways by various societies or individuals, depending on the given geographical and socio-economic conditions, living standards; national, ethnical, and religious traditions; history, policy; age, sex, educational level, position in the social hierarchy; etc. Sustainable development is a global objective that includes efficient multifunctional agriculture: using environment-friendly, energy- and material-saving technologies and paying special attention to quality; and a socially acceptable rural development, simultaneously. The given land resources have to be used and managed in harmony with the production and protection.

The paper gives information about both the genesis, and a survey of, the descriptors used for the documentation of plant genetic resources held in ex situ crop collections. The first international documentation standards were developed by the FAO in the 1950s. In 1974, a specific body for plant genetic resources, the IBPGR (International Board for Plant Genetic Resources), was established within the FAO. Since the 1970s, the descriptor lists for main crop collections have been developed, including passport descriptor sets. For the most part, the passport descriptors were common to all crops, with only slight differences. In 1997, the first attempt to create a standard set of descriptors resulted in 24 passport descriptors developed by FAO and IPGRI (International Plant Genetic Resources Institute) working in cooperation. In 2001, the official Multi-Crop Passport Descriptor list (MCPD) was published, including a revised standard set of 28 descriptors. The European ex situ crop catalogue (EURISCO) enlarged the standard set of passport descriptors by adding 6 additional fields in 2002; and another 2 new descriptors were added in November of 2008. A global level of data compatibility is preferred; therefore projects aimed at world-wide utilization and standardization of systems, such as GRINGlobal, and Accession-Level Information System (ALIS), are supported.

Organic anthropogenic compounds such as polycyclic aromatic hydrocarbons, polychlorinated biphenyls, nitroaromatics, dioxins, various pesticides and natural compounds can enter the aquatic environment. These lipophilic compounds are readily taken up into the tissues of aquatic organisms where biotransformation via Phase I and Phase II metabolism can in part, determine the fate and toxicity of the xenobiotics. In this study on gilthead seabream (Sparus aurata), liver microsomal ethoxyresorufin O-deethylase (EROD), methoxyresorufin O-demethylase (MROD), penthyloxyresorufin O-depenthylase (PROD), benzyloxyresorufin O-debenzylase (BROD), aniline 4-hydroxylase (A4H), N-nitrosodimethylamine N-demethylase (NDMA-DE), aminopyrine N-demethylase (APND), caffeine N-demethylase (CN3D) and erythromycin N-demethylase (ERND) were determined. A4H, ERND, NDMA-ND, EROD and PROD activities increased in gilthead seabream (Sparus aurata) liver microsomes of different ages, while CN3D and APND activities decreased. MROD activities were barely detectable in mature fish whereas BROD activities were not detectable at all ages studied. Results were also recorded at the protein level by Western blotting using anti-CYP1A, CYP2E and CYP3A antibodies. In conclusion, elevated levels of gilthead seabream liver microsomal CYP450 enzyme activities might reveal possible exposure to various exogenous compounds, which might affect the desired responses to drugs, hormones and dietary supplements used during breeding.

Coarse woody debris (CWD) is an important structural and functional component in forests in Northern Iran. In this study we determine the temporal patterns of CWD in Kheyroud Forests by examining the CWD volume in different decay classes and size classes along a chronosequence of secondary forest succession. The volume of CWD followed the general "U-shaped" temporal trend: the highest in the late successional forest (51.25 m³.ha^-1), lowest in the middle successional forest (25.95 m³.ha^-1) and intermediate in the early successional forest (37.05 m³.ha^-1). The late successional forest had a larger amount of logs, snags and stumps than the other two forests. In contrast, the snag volume did not differ between the late and middle successional forest. CWD in decay classes III and V was greater in the late successional forest than that in the other two forests, while CWD in decay classes II and I did not differ among the three successional forests. CWD in class II and I was significantly higher in the early successional forest than that in the middle successional forest. In the early and middle successional forests, CWD in early decay class was dominated by Carpinus betulus L. followed by Fagus orientalis Lipsky. In the late successional forest, CWD in early decay class was dominated by Fagus orientalis while CWD in the late decay class was dominated by Carpinus betulus. While forest succession had a large influence on the amount of CWD in different decay classes, it had no effect on CWD distribution among the different size classes. Our results suggest that both anthropogenic and natural disturbances have had a long-term effect on the distribution of CWD among three forests.

An evaluation of the effects of soil structural heterogeneity on maize (Zea mays L.) root system architecture was carried out on plants grown in boxes containing fine soil and clods. The clods were prepared at two levels of moisture (0.17 and 0.20 g/g) and bulk density (ranges 1.45-1.61 g/ml and 1.63-1.79 g/ml). Soil moisture directly affected the probability of clod penetration by maize roots. Primary roots inside the clods manifested morphological deformations in the form of bends. We observed a significant increase of bends per root length at lower soil moisture (P = 0.02). Root diameter and branching density increased, and lateral root length decreased considerably inside the clods. However, once emerging out of the clods and into free soil, values of all three characteristics remained low. While changes in root diameter were caused mainly by clod moisture (P < 0.05), length of lateral roots was related to bulk density (P < 0.01). Branching density was modified exclusively by an interactive effect of both factors (P < 0.05).

Four on-farm plantations (KRNAP Vrchlabí, the Orchard of Reconciliation in Neratov, Podyjí National Park, and Šumava National Park) were successfully established in a traditional form, with large orchard trees on seedling rootstocks. Certain accessions (cultivars) for on-farm conservation in the given locality were selected, according to the incidence and presentation of genotypes in these particular areas. This information was obtained by localization of fruit trees in situ and the determination of certain cultivars. Nursery stock production for onfarm plantations is described. Because of the longevity of the plantation, seedling rootstocks were used for the production of planting materials for the on-farm plantations. Techniques of on-farm plantation establishment and orchard management are stated within the paper. Four established on-farm plantations have ensured the long-term preservation of landraces in their original areas.

Astragalus excapus L. and Astragalus austriacus Jacq. are regarded as critically endangered species in Slovakia. They are threatened by environmental impact, natural succession, as well as by human activities. Monitoring them is an important tool in determining their status and in making management decisions for their protection. In this contribution, a summary of the basic terrain endeavours, current status, locality and species description, habitat preferences, possible threats, current protection, and management activities are presented.

The growth, survival, damage and provenance × environment interactions of 30 provenances of Norway spruce (Picea abies L.) from Poland, Slovakia and the Czech Republic, were analyzed at the age of 26 years. Significant effects of altitude and site quality but no geographic trends were dectected in the series of 5 provenance plots. Correlation of growth and survival appeared to be insignificant at individual plots and their series. The highest differentiation among provenances was revealed on the plots at the minimum and maximum altitudes (350 and 950 m). Several Slovak (Western-Carpathian) provenances proved to grow significantly better than the average at nearly all plots, and also exhibited insignificant provenance × site interaction. Indigenous provenances from the southern part of the Western Carpathians showed higher adaptability to sites in lower altitudes with longer vegetation but seasonal water deficiency.

Infestation density of four the most common spruce bark beetle species was estimated on 15 study sites (10 trees per site) in the Kysuce model region in 2006. Five half-metre long sections of the stem were selected and dissected at the base of the stem; midway between the base of the stem and the base of the crown; just below the base of the crown; in the middle of the crown; and in the upper part of the crown. The infestation density of bark beetles, expressed as the number of mating chambers per dm², was determined. Ordinary kriging was then used to produce smooth maps and visualize spatial distribution of study species. Maps with isolines indicating high infestation were produced for study species (I. Typographus over 0.38; (I. amitinus over 0.15; (I. duplicatus over 0.11; and P. chalcographus over 0.415 nuptial chambers per dm²). Ips typographus L. remained dominant species on majority of sites having high intensity of infestation. Lower altitudes in the south-eastern part of the region were often infested by I. duplicatus Sahlberg and also by I. typographu and Pityogenes chalcographus L. Higher elevations in the north-eastern part of territory in the vicinity of border with Poland were heavily infested by I. amitinus Eichhoff (often with I. typographus). P. chalcographus was abundant on majority of territory - mainly in southern half of area. However locally, it was found in extremely high abundance. The results suggest the need for control measures set up jointly against the most abundant bark beetle species in study region.

This paper presents a proposal of four variants of quantifiers for the numerical expression of qualitative attributes of forest ecosystems, for example site, naturalness, biodiversity, ecological stability, threat of injurious agents, status of forest biotopes of European significance in the NATURA 2000 network and so on. Quantifiers enable to completely characterise the whole set of these qualitative attributes of the ecosystem by one number which directly indicates the relative approximation of the ecosystem (in %) to the required most favourable status. They have more advantages: different numerical operations can be done with them, it is possible to aggregate evaluated units of the ecosystem to larger entities, to determine average value, variability and confidence limits of the final evaluation and to compare resulting statuses mutually or very objectively on the principle of biometric monitoring in a longer time. The construction of quantifiers is opened and it arbitrarily enables to choose input parameters at need (numerical quantifications of ecosystem quality statuses and weights of their criteria and indicators) and to search for optimal solutions. The reaction of quantifiers to different input situations is analysed on model examples and suggestions for their introduction into practice are presented. Special PC software was elaborated for the automated calculation of quantifiers.

The objective of this paper was to obtain information about the effect of interactions and different agronomical measures on autumn saved herbage of different sites in Central Europe (Czech Republic, Germany, Hungary, Poland). Within the different sites, the effect of the factors pre-utilisation (accumulation since June, July or August) and winter harvest date (November, December or January) on dry matter (DM) yield and digestibility of organic matter (DOM) was investigated over three consecutive years. All results were examined by analysis of variance and least-significance differences (LSD) were calculated (with P < 0.05). For all years, date of winter harvest was the most important source of variance. The highest yields were attained in November (varied from 2.3 to 0.8 t/ha), the lowest in January (from 1.5 to < 0.2 t/ha). The highest DOM concentration (from 70.4 to 52.4% of dry matter) was reached in November, and it decreased until January (from 59.6 to 35.2% of dry matter). Predominantly caused by the prevailing climatic conditions, the DM yields of the sites varied considerably during winter, showing a significance for the interaction winter harvest date × site as well as for the factor site. The utilisation of autumn saved herbage, pre-utilised in July, might be the best opportunity providing an adequate quantity and DOM for suckler cows until the end of the year, but the prevailing climatic conditions at different sites inCentral Europe finally decide on the practicability of winter grazing.

The primary objective of this paper is to study the interspecific variation of ¹⁵N natural abundance in two dominant conifer tree species, Scot pine (Pinus sylvestris L.) and Norway spruce (Picea abies L. Karst) in a N-limited mixed boreal coniferous forest in southern Finland. Both a mature tree stand (a natural forest stand) and a stand of seedlings in a clear-cut area were considered. We analyzed %N and δ15N natural abundance in needles, branches, litter and soil of the both above-mentioned stands. Pine needles had higher N concentrations than spruce needles, both in mature forest (pine = 1.09%, SE ± 0.02 and spruce = 0.79%, SE ± 0.02) and in the clear-cut area (pine = 1.01%, SE ± 0.07 and spruce = 0.74%, SE ± 0.04). Furthermore, pine needles were significantly more depleted in δ15N natural abundance than the spruce needles, both in the mature forest (pine = -5.6‰, SE ± 0.1‰ and spruce = -4.0‰, SE ± 0.2‰) and in the clear-cut sites (pine = -2.8‰, SE ± 0.2‰ and spruce = -2.1‰, SE ± 0.3‰). The more pronounced depletion of ¹⁵N in the pine foliage might be connected to its different fungal associates in the roots compared to spruce roots. We assume that the mycorrhizal N-uptake is very prominent at the N-limited site. After clear-cutting, needles of the seedlings and the uppermost part of soil organic layer were found to be more 15N-enriched than at the natural forest site. This was attributed to an increased level of nitrification in the clear-cut site soil.

The present paper deals with data obtained from fifteen years old Norway spruce (Picea abies [L.] Karst.) progeny test established at three sites in the Sázava River region. Parameter under the evaluation was a tree height in 15 years following the establishment of the trial. Genetic parameters were estimated using the REML (Restricted Maximum Likelihood) procedure followed by the BLUP (Best Linear Unbiased Prediction). Genetic parameters estimates were used to predict genetic gain in three alternative selection strategies. The value of gain depends on target value of gene diversity. 10-15% gain is due to selecting breeding population composed of 50 individuals. Based on these quantitative findings, current and future research orientation is discussed.

The genetic variation in 20 provenances of European larch, growing under site conditions of the Beskid Sądecki mountain range (experimental area in Krynica), was investigated during a long-term study carried out within the 1967 Polish Provenance Experiment on Larch. Data consisted of diameter measurements taken outside bark on standing trees of the analyzed provenances. Results showed that there was no distinct variation in the tested larch populations in respect of stem form. Some differences between compared provenances in respect of stem taper and form factor were the result of differences in tree height and diameter.

Web technology is a major element of the Internet. The various and inexpensive possibilities to use this technology allow for the minimisation of differences between rural and urban areas. This article focuses on the use of www technology for creating web sites. It outlines theoretical starting points for planning web sites, as well as practical methods, which are utilised for setting up the web presentation of a farm.

As long as the land market in Slovakia is not completely developed and land market prices introduced, the officially assigned land prices are practically in use. At the present time, land prices should express the supply prices, which cover the income effect of the land site under the socially necessary costs. In this situation, for the temporary period, centrally assigned fixed land prices could represent the effective supply and demand prices in case they correspond to the mentioned conditions. At present, the official prices are used for fiscal purposes and the land property rights.

A study of labour productivity was conducted in fully mechanised harvesting technologies. The study revealed that the productivity of harvesters was particularly affected by the average tree volume of the felled trees, and the productivity of forwarders was affected mainly by two factors - haulage distance and machine payload. Dependences of other factors such as natural and site conditions, technical parameters and skills of operators could not be demonstrated. Regression equations of dependences were created for all these three significant criteria and costs per cubic meter of processed timber were calculated for them according to the cost function. A regression function was then developed for the forwarder that takes into account both significant criteria influencing the forwarder productivity.

The objective of this study was to assess the impact of vegetation on the hydraulic conductivity of sandy soil at the locality Mláky II at Sekule (southwest Slovakia). The measurements were taken on the surface of a meadow (Meadow site), a 30-year old Scots pine (Pinus sylvestris) forest (Forest site) and a glade (Glade site). In the glade, the measurements were also taken in the depth of 50 cm (Pure sand) to reduce the influence of vegetation on the soil properties. It was found that the unsaturated hydraulic conductivity k_r(-2 cm) as reduced due to the soil water repellency increased in the same order: Forest soil < Glade soil ≈ Meadow soil < Pure sand, similarly as decreased the water drop penetration time t_p: Forest soil > Glade soil ≈ Meadow soil > Pure sand, which could refer to an inverse proportionality between the capillary suction and hydrophobic coating of the soil particles. The saturated hydraulic conductivity K_s increased in the following order: Meadow soil < Glade soil ≈ Forest soil < Pure sand; more than two-times higher K_s at both the Forest and Glade sites than that at the Meadow site could be the result of both the patchy growth of vegetation with some areas of bare soil at the Glade site and the macropores (dead roots) in more homogeneous humic top-layer at the Forest site. The share B_r of flux through the pores with radii r longer than approximately 0.5 mm decreased in the order: Forest soil » Meadow soil > Glade soil » Pure sand, revealing the prevalence of preferential flow through macropores (dead roots) in the Forest site and a negligible share of macropores in the Pure sand.

The article summarizes findings drawn form the research carried on within the European project "Best e-European Practices" with a focus on digital SMEs only. Case studies are used to describe good practices. Cases studies are coded structurally using a set of indicators for each success factor and thus provide for learning of the potential users. Synthesis and generalization has been done on factors explaining motivations for introducing e-practices, the results firms seek to achieve and the benefits from the adoption of digital technologies.

Fish fauna and macrozoobenthos were surveyed at 51 and 32 sampling sites, respectively, in mountain and submountain streams of the Vlara stream drainage area in the Bílé Karpaty Mountains. The aim of the study was to bring wide knowledge of their aquatic communities with their indicative value of the ecological quality of particular sites. Fish were sampled by electrofishing and macrozoobenthos was collected by kick-sampling using a bottom net (mesh size 500 μm) at the majority of the respective sites. In total, 15 fish species were registered in all profiles. At four headwater sites no fish were recorded at all. Brown trout (Salmo trutta m. fario) and stone loach (Barbatula barbatula) were the most frequent species at the sites under study (73% and 67%, respectively). A similar frequency (41%) was documented for chub (Leuciscus cephalus), gudgeon (Gobio gobio) and minnow (Phoxinus phoxinus). The species richness increased downstream in the mainstream of the Vlára stream with the maximum of 10 species found at the lowest study site. Qualitative data on fish assemblages did not fully correspond with the environmental stress. On the other hand, macrozoobenthos indicated a minor decrease in water quality downstream of small villages and farms. Larvae of dipterans (Chironomidae and Simuliidae in particular) and mayflies (Ephemeroptera) dominated among the temporary water macroinvertebrates while numerous populations of Gammarus fossarum (Amphipoda) and in some cases also of Asellus aquaticus (Isopoda) were recorded as permanent inhabitants of clean and polluted stretches, respectively.

The 4-nitrophenyl phosphate method for acid phosphomonoesterase (EC 3.1.3.2; acid orthophosphoric monoester phosphohydrolase) determination was slightly modified to increase the sensitivity and the stability of the 4-nitrophenol coloured complex in samples rich in humic substances and easily soluble organic compounds. Based on an approach used for mycorrhizal roots, the new analytical protocol was tested on samples taken from a single forest site with a large variation in soil types. Distinctive properties of forest soils and the accuracy/repeatability of the optimised technique were considered in the selection of the most appropriate analytical steps. Finally, the acid phosphomonoesterase activity was expressed in μg of 4-nitrophenol/g fresh soil recalculated dry matter/h released after hydrolysis of 4-nitrophenyl phosphate in sodium tetraborate/succinic acid buffer at pH 4.8. The modified method proposed was statistically compared with other procedures and the results obtained were found to give merit to these slight modifications. The rationale behind the slight modifications and their comparative significance was reported. Due to high soil complexity, it is suggested that a single laboratory measurement of chemical and biochemical properties is of limited application with forest soil and can be only one component of a broadly focused ecological analysis.

Specific chemosignals (pheromones) have an important role in the antipredator behaviour in amphibians and other vertebrates. However, relatively little is known about the occurrence of chemical alarm cues just in amphibians. The site of chemosignals perception is vomeronasal system. The presence of the vomeronasal system in aquatic amphibians indicates that it did not arise as an adaptation to terrestrial life. Predators may inhibit mate search of some species, and male newts probably take greater risks during the breeding season. Field tests demonstrated different responses to male newt extract - probably trade-off that incorporates risk and resource sensitivity. Response to chemical alarm signals has been documented for tadpoles of frog and for several species of salamander. The response of tadpoles to predator includes morphological modifications and influence of coloration, growth and development retardation. Tadpoles of Rana aurora release a chemical that provides conspecifics with an early warning of predator presence. Bufo boreas tadpoles living in the presence of conspecific alarm cues and chemosignals of specific predators reduce the time of metamorphosis in order to reduce the time in the presence of its predators. Presence of conspecific alarm substances in water and predators' waste products have an important role in the chemical detection of predators by tadpoles of Rana temporaria and Bufo bufo. Tadpoles of Rana utricularia significantly decreased the growth and increased the mortality of Hyla cinerea tadpoles on the basis of behavioral and chemical interference. Rana utricularia tadpoles apparently use both chemical interference and aggressive behavior in securing a competitive advantage over H. cinerea tadpoles. The response of tadpoles of Rana aurora to tadpoles of Taricha granulosa appear be similar to their response to tadpole extract in eliciting alarm, while insect-fed newts would have less of an effect since predators consuming other species may be less of a threat. In some cases (e.g. in Bufo bufo and B. calamita) chemosignals released in response to threat by predators (direct attack or detection of the predator scents) exert their effects across species.

Fertilization represents a measure, used as exceptional treatment managing forest stands and ecosystems as a whole. It is used since the beginning of the 20^th century worldwide, starting in the Central Europe. The beginnings were on empirical basis, later on, the scientific background was developed profoundly. Several forms and methods, as well as aims are topical at present: - Since the beginning, restoration of degraded sites and amelioration of primarily extreme soils was the aim. In the poorest regions, e.g. in the NE Germany, different means were used to increase site productivity and stability. Also in the Czech countries, amelioration played important role restoring degraded and devastated localities. - To increase site productivity, commercial fertilization was used worldwide, as well as it was applied in all continents with intense forestry practices. It became a part of the "silviculture" sensu stricto in the commercial, industrial forestry. - Supporting the growth and prosperity of forest plantations, on sites of different characters, was a broadly intended target of fertilizers application. - Since the air pollution calamity, fertilization is one of the main counter-treatments for improvement of the situation, lowering and preventing the soil acidification and nutritional degradation. Both direct as well as indirect methods are used. At the direct fertilization, nutrients in the fertilizers increase and improve the nutrient cycles over the degraded or natural level. This causes an increase in the forest ecosystem production as the main aim of such a treatment. In the indirect way, the amelioration material accelerates the bio-cycles by improving biological activities of the soil - liming is the best example of these activities. Nutrients are mobilized by enhanced activity of the soil biota, increasing organic matter mineralization and decay. This also represents the main ecological risk of these activities: the enormous and non-natural organic matter decay. Different types of fertilizer can be used: liquid, firm, powdered, pelletized, based on natural substances such as carbonates or silicate nutrient-rich (basic) rocks. In all cases, the uses of all these treatments have to be based on the detailed ecological analysis of the locality, of the site and of the forest stand. Only in this case, fertilizer effects can be optimized and the risks minimized.

In addition to the results published in the first communication (Opitz von Boberfeld et al., 2006) this paper presents crude protein, energy (ME) and ergosterol concentrations of autumn saved herbage at different sites in Central Germany, Poland, Hungary and the Czech Republic. Within these sites, the influence of the factors pre-utilisation and winter harvest date was tested over three consecutive years. Related to the different climatic conditions of the sites, crude protein concentrations of the growths pre-utilised in July varied from 149 g/kg in November to 134 g/kg of dry matter (DM) in January. The influence of climatic conditions was different on each location and varied depending on the year. Generally, the consistent effect of the factor "site" related to altitude could not be observed. While the energy concentrations decreased with advancing winter and partly reached the values below 6 MJ ME/kg of DM in January, the ergosterol concentrations increased. The results demonstrate that under Central European conditions autumn saved herbage, pre-utilised in July, could provide adequate quantity and quality for suckler cows until December. Afterwards, the utilisation of preserved forages becomes essential.