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In this study, the effects were investigated of salinity, foliar and soil applications of humic substances on the growth and mineral nutrients uptake of Corn (Hagein, Fardy10), and the comparison was carried out of the soil and foliar applications of humic acid treatments at different NaCl levels. Soil organic contents are one of the most important parts that they directly affect the soil fertility and textures with their complex and heterogenous structures although they occupy a minor percentage of the soil weight. Humic acids are an important soil component that can improve nutrient availability and impact on other important chemical, biological, and physical properties of soils. The effects of foliar and soil applications of humic substances on the plant growth and some nutrient elements uptake of Corn (Hagein, Fardy10) grown at various salt concentrations were examined. Sodium chloride was added to the soil to obtain 20 and 60mM saline conditions. Solid humus was applied to the soil one month before planting and liquid humic acids were sprayed on the leaves twice on 20^th and 40^th day after seedling emergence. The application doses of solid humus were 0, 2 and 4 g/kg and those of liquid humic acids were 0, 0.1 and 0.2%. Salinity negatively affected the growth of corn; it also decreased the dry weight and the uptake of nutrient elements except for Na and Mn. Soil application of humus increased the N uptake of corn while foliar application of humic acids increased the uptake of P, K, Mg,Na,Cu and Zn. Although the effect of interaction between salt and soil humus application was found statistically significant, the interaction effect between salt and foliar humic acids treatment was not found significant. Under salt stress, the first doses of both soil and foliar application of humic substances increased the uptake of nutrients.

The origin of the differences in the water regime components of 0-0.6 m soil profile was identified in extensively managed permanent grasslands (PG, variants: once cut - 1C, twice cut - 2C, nocut - NC, mulched June - MVI, mulched July - MVII) using the method of the soil water balance (drainage lysimeters). The differences in the water regime of the experimental variants manifested themselves depending on adequate soil water storage in the period when the amounts of transpiring biomass in individual variants differed markedly: (i) at the beginning of the vegetation period, when the surface litter in the NC and 1C variants reduced the actual evapotranspiration (ETA), (ii) at the time of mowing and mulching (M), when these treatments (mainly M) increased the soil water supply by ca 10-20 mm per month and decreased the ETA values by 1-2.5 mm per day for about 2-4 weeks as compared to non-mown variants on the given date, and (iii) as a result of the presence of different agrobotanical groups with distinct transpiration intensity (leguminous plants with a higher transpiration intensity in the 2C variant compared to grasses). The post-M reduction in evaporation was compensated by a higher total transpiration resulting from an increase in the aboveground phytomass. The lowest water consumption with the highest supply to the groundwater resources was recorded in the NC and 1C variants. The 2C variant containing leguminous plants with high water requirements had the highest consumption of water for evaporation and the lowest amount of water runoff from the soil profile. The identification of the water regime differences in individual variants helped determine the appropriate PG management with the aim to increase the underground water levels in the protection zones of water resources. The 1C variant of management is recommended mainly in the source areas of groundwater with lower productivity soils. In the accumulation areas of water resources (floodplain areas) with a deep soil profile and highly productive grassland, the 2C variant is required; mulching, which would largely support the yielding capacity of grassland, should be avoided. Mulching may occasionally be used as a relatively suitable method for the sites with a low yielding capacity in the source area.

A 12-day incubation experiment with the addition of glucose to soils contaminated with persistent organic pollutants (POPs) was carried out in order to estimate the potential microbial activities and the potential of the soil microbial biomass C to degrade 1,1,1-trichloro-2,2-bis(p-chlorophenyl) ethane (DDT), polychlorinated biphenyls (PCB) and polycyclic aromatic hydrocarbons (PAHs). The microbial activities were affected in different ways depending on the type of pollutant. The soil organic matter also played an important role. The microbial activities were affected particularly by high concentrations of PAHs in the soils. Soil microorganisms in the PAHs contaminated soil used the added glucose to a lesser extent than in the non-contaminated soil, which in the contaminated soil resulted in a higher microbial biomass content during the first day of incubation. DDT, DDD and DDE, and PCB affected the soil microbial activities differently and, in comparison with control soils, decreased the microbial biomass C during the incubation. The increased microbial activities led to a significant decrease of PAH up to 44.6% in the soil long-term contaminated with PAHs, and up to 14% in the control soil after 12 days of incubation. No decrease of PAHs concentrations was observed in the soil which was previously amended with sewage sludges containing PAHs and had more organic matter from the sewage sludges. DDT and its derivates DDD and DDE decreased by about 10%, whereas the PCB contents were not affected at all by microbial activities. Studies on the microbial degradation of POPs could be useful for the development of methods focused on the remediation of the contaminated sites. An increase of soil microbial activities caused by addition of organic substrates can contribute to the degradation of pollutants in some soils. However, in situ biodegradation may be limited because of a complex set of environmental conditions, particularly of the soil organic matter. The degradability and availability of POPs for the soil microorganisms has to be estimated individually for each contaminated site.

In order to archive the millennium goals of which water for all by the year 2015 is a major component; all efforts must be made to efficiently utilise the available water resources in various parts of the world and more importantly in Africa which has been described as the worst hit. In Nigeria, water scarcity in terms of quality and quantity is a major problem. In order to assess the potential of the River Osun at Apoje sub-basin located in the southwestern part of Nigeria, the streamflow and gauge height data of 18 years (1982-1999) were collected from Ogun-Osun River Basin and Rural Development Authourity, Abeokuta, Nigeria. A rating curve was drawn for the station by plotting the gauge heights against their annual maximum discharges. The annual cumulative inflows for each year were determined and plotted against water years to evaluate their spatial distributions. Mass curve was drawn for each year and their potential reservoir capacities were determined. The results show that, at the return periods of 10, 25, and 50 years, the upper flood limits of 430, 451, and 458 m³/s, respectively, were obtained at 95% confidence intervals and the level of significance of 0.025. The coefficient of determination r² of 0.9984 shows a good fit of the rating curve. The annual cumulative inflow in the sub-basin varies from 60 to 306 billion m³ of water in 18 years. The average annual cumulative inflow was 125 billion m³ of water while the interannual variability was 42%. The intraanual variability was between 56 and 83%. The maximum potential reservoir capacity of 22 billion m³ of water can be built in the area to cater adequately for diverse uses in the sub-basin.

Soil water repellency has important consequences for ecological and hydrological properties of soils and usually retards infiltration capacity and induces preferential flow. This phenomenon has been known to occur on a wide range of sites under a variety of climatic conditions. The objective of this study was to investigate and characterize soil water repellency on forest sites with identical substrate and climatic conditions, differing in tree age and species. In the Vester Torup Klitplantage, an area comprising a conifer dominated forest plantation stocking on sandy deposits in a coastal setting near the Jammer Bay in north-western Jutland/Denmark, four different forest plots were investigated for water repellency effects four times in 2005. To measure soil water repellency, the water drop penetration time test and the critical surface tension test were carried out. Both tests revealed a seasonal variability in water repellency, exhibiting the highest water repellency for the upper 10 cm of the soil during the summer months, whereas the variability between the different plots seems to be less significant. There was no coherence between humus forms, thickness of litter layer and water repellency.

: In November 2004, forest stands in the Tatra National Park (TANAP) were affected by windthrow and in July 2005, the wildfire broke out on a part of the affected area. The objective of this study is to evaluate the impact of the windthrow and fire disturbances on soil microbial activity. Basal and potential soil respiration, N-mineralisation, catalase activity, soil microbial biomass, and cellulase activity were measured in soil samples taken from the A-horizon (depth of 0-10 cm) along 100 m transects established on 4 plots (reference site, burnt, non-extracted, and extracted sites) in October 2006. Some soil microbial characteristics exhibited a high spatial variability, especially microbial biomass and N-mineralisation. Significant differences in soil microbial characteristics (especially basal soil respiration and catalase activity) between plots were found. Generally, the highest microbial activity was revealed on the plot affected by fire. Soil microbial activity was similar on the extracted and non-extracted sites.

Aluminium (Al) mobilisation in the forest soils is a serious problem due to the soil acidification. The rate and magnitude of leaching of Al and other elements and compounds from soils can be examined by means of percolation experiments. Aluminium elutriation was studied under laboratory conditions using undisturbed samples of forest topsoil from the Paličník area in the Jizera Mountains (Czech Republic), which originated under two different vegetation covers: European beech (Fagus sylvatica L.) and Norway spruce (Picea abies (L.) Karst). Ponding infiltration was performed using three subsequently applied solutions. KCl solution was used to simulate the soil solution. Solutions with sulphates and nitrates addition (of two different pH values) were used to simulate acid rainfall. Passing liquid phase was analysed with respect to Al content and aluminium speciation. Differences were found in Al content and transport between different soils under spruce and beech covers. The soil sample under the spruce forest (SF sample) had a higher initial Al content than the soil sample under the beech forest (BF sample). As a result, the aluminium leaching from the spruce soil sample and the final content of water-extractable Al in the soil (Al content after the leaching experiment) were higher compared to the beech soil sample. This suggests that Al mobility and potential toxicity in the beech forest are grater than those in the spruce monoculture when studied in the acidification endangered areas.

Soil quality is a measure of the ability of soil to carry out particular ecological and plant productive functions. It reflects the combination of chemical, physical, and biological properties. Some of the soil properties are relatively more important than the others and unchangeable. Others can be significantly changed by human activity. Nowadays, three groups of soil functions are usually defined: soil utility function (productive function, infrastructure area, source of materials); functions of soil in the environment (non-productive functions such as: water infiltration and water retention, transport of matter, buffering and sanitary functions); soil cultural function (history of nature and humans). The cultural function is, from our point of view, different from the others. The complex assessment of the soil quality is the topic of this paper and includes both the productive and environmental functions. The productive function (productive potential) of Czech soils has been long studied and is ± known. It is expressed by means of a one-hundred-point scale in the Czech Land Evaluation System. Its point values depend on different soil and local characteristics together with the natural conditions and their influence on the plant production. A similar principle was used for the assessment of the non-productive soil functions. The importance of the individual soil characteristics is defined. The values of the environmental soil function potentials are determined from the common soil characteristics and are compared with the values of the soil productive potential. Total soil quality can be then expressed as the average or as the sum of the points for all individual functions. Some selected function can be preferred by increasing its value coefficient for a specific land use area (for example, an area for obtaining underground water). Three texturally different forms of Chernozem (middle textured, clayic, arenic) which correspond to the Main Soil Units of the Czech Land Evaluation System are given as an example of the assessment. The evaluation of the total soil quality would then involve not only the agricultural and locality determined financial values but also an assessment of all environmental functions of the soil.

The settlements situated on broad flat floodplains of rivers are threatened by floods during increased water flows in the rivers. The floodplain of the Dyje river situated in the area between the Nové Mlýny water reservoir and Břeclav has been protected from former annual floods since the 70s of the last century due to the water-management measures. The realised measures including the construction of the new floodway protect the town of Břeclav as well. A long-term research into the soil water regime of the floodplain forest is underway in the region. The results obtained document its historical evolution and current status. Only in the early April of 2006 (i.e. after 34 years), an unexpected "flash flood" occurred again due to a specific climatic situation. The combination of the high snow cover in higher parts of the basin and a rapid warming up caused an intensive runoff. The so-called dry polder (floodplain forests, meadows and fields) above Břeclav protected the town and its infrastructure from potential catastrophic consequences.

This paper is focused on soil organic matter quality assessment in acid forest soils. Soil samples were collected in the Jizera Mountains region. Vegetation cover of sampling sites was formed by spruce or beech monocultures. Humus quality was assessed by the ratio of absorbances of pyrophosphate soil extract at the wavelengths of 400 and 600 nm (A400/A600). Humus fractionation was performed on selected soil samples. DRIFT spectra of individual fractions were measured. Higher pH and lower C and N contents were found in beech forest than in spruce forest. A400/A600 well correlates with C and N contents (r = 0.510*** and 0.615***, respectively). C and N content increases as to humus quality decreases. DRIFT spectra of fulvic acids turned out to be unsuitable for describing differences in humus quality. DRIFT spectra of humic acids and humin were hence more suitable. The difference between spruce and beech forest was found in 1514.cm-1 (C=C bounds of benzene rings) and 1550 cm-1 (N-H bounds in monosubstituted amides) bands intensities. Humic acids and humin coming from the O horizons of beech forest are relatively enriched by nitrogen functional groups. Values of humic acids aromaticity index did not differ between beech and spruce forests. DRIFT spectroscopy was shown as a possible method for detailed humus quality studying.

Sediment is a natural component of riverine environments and its presence in river systems is essential. However, in many ways and many places river systems and the landscape have been strongly affected by human activities which have destroyed naturally balanced sediment supply and sediment transport within catchments. As a consequence a number of severe environmental problems and failures have been identified, in particular the link between sediments and chemicals is crucial and has become a subject of major scientific interest. Sediment load and sediment concentration are therefore highly important variables that may play a key role in environment quality assessment and help to evaluate the extent of potential adverse impacts. This paper introduces a methodology to predict sediment loads and suspended sediment concentrations (SSC) in large European river basins. The methodology was developed within an MSc research study that was conducted in order to improve sediment modelling in the GREAT-ER point source pollution river modelling package. Currently GREAT-ER uses suspended sediment concentration of 15 mg/l for all rivers in Europe which is an obvious oversimplification. The basic principle of the methodology to predict sediment concentration is to estimate annual sediment load at the point of interest and the amount of water that transports it. The amount of transported material is then redistributed in that corresponding water volume (using the flow characteristic) which determines sediment concentrations. Across the continent, 44 river basins belonging to major European rivers were investigated. Suspended sediment concentration data were collected from various European basins in order to obtain observed sediment yields. These were then compared against the traditional empiric sediment yield estimators. Three good approaches for sediment yield prediction were introduced based on the comparison. The three approaches were applied to predict annual sediment yields which were consequently translated into suspended sediment concentrations. SSC were predicted at 47 locations widely distributed around Europe. The verification of the methodology was carried out using data from the Czech Republic. Observed SSC were compared against the predicted ones which validated the methodology for SSC prediction.

Environmental pollution of heavy metals from automobiles has attained much attention in the recent past. The present research was conducted to study heavy metal contamination in roadside soils of northern England. Roadside soil samples were collected from 35 sites in some counties of northern England and analysed for four heavy metals (cadmium, copper, lead, zinc). Their concentrations and distributions in different road verge zones (border, verge, slope, ditch) were determined. Lead concentration was the highest in the soil and ranged from 25.0 to 1198.0 μg/g (mean, 232.7 μg/g). Zinc concentration ranged from 56.7 to 480.0 μg/g (mean, 174.6 μg/g) and copper concentration ranged from 15.5 to 240.0 μg/g (mean, 87.3 μg/g). Cadmium concentration was the lowest in the soil and varied from 0.3 to 3.8 μg/g (mean, 1.4 μg/g). Though the levels of heavy metals in roadside soils were higher as compared to their natural background levels in British soils, their concentrations in general, however, were below the 'critical trigger concentrations' for the contaminated soils. All the four heavy metals exhibited a significant decrease in the roadside soils with the increasing distance from the road. The border zone had the highest mean concentration of the four metals whereas the ditch zone exhibited the lowest mean concentration.

Soil infiltration capacity is one of the key factors in the soil protection against unfavourable effects of water erosion. The purpose of its measuring was to compare and evaluate the changes of the soil physical properties and of water infiltration into soil caused by different intensity of soil cultivation at two individual sites. The ploughing (PL), shallow tillage (ST), and direct drilling (NT) effects on the soil physical properties, water infiltration into soil, and soil surface coverage with the crop residua under the soil condition loamy Haplic Luvisol, with long-term growing of maize (Zea mays L.) - Agroservis, 1^st Agricultural, a.s., Višňové - and clay soil of Calcic Chernozem (Cooperative farm Klapý), were compared. Soil bulk density values in the variant with ploughing showed in the depth up to 0.20 m considerably lower values as compared with the variants shallow tillage and direct drilling. Nevertheless, in the subsoil layer the bulk density of soil in the variant with ploughing increased in comparison with other variants. The results were also confirmed by the cone index values. At the plots in Višňové the infiltration was evaluated utilising the double ring infiltrometer, and by means of the coloured water infiltration. The results revealed significant differences in the water infiltration rate at various stages of the soil loosening. The highest average values were recorded for ploughing (1.00 dm³/min). The lowest values were found for the shallow soil tillage (0.18 dm³/min). The variant with direct drilling showed values of 0.53 dm³/min. The coloured water infiltration evaluation showed a different character of water flow in soil. The variant with ploughing showed water saturation in the top layer, the variants with reduced tillage were characterised by vertical macropores and crack effects with the water drain into deeper layers. Ploughing proved its advantage for the short-term rainfall retention. Similar results were also brought in the evaluation on the plot with clay soil (Klapý). The loosening effect was evident during coloured water infiltration in the period of snow thawing. The loosed soil layer showed a significantly higher soil water holding capacity as compared with variants with reduced soil tillage. The result showed major differences in the water infiltration rate into soil and different characters of water infiltration into soil at different soil tillage.

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.

Two different models (WBS FLAB, WaSiM-ETH) were used in the project HochNatur (flood prevention and nature conservation in the Weißeritz catchment in the Eastern Ore Mts. - Erzgebirge) to determine risk areas with quick runoff processes and to simulate the discharge. It was done in different scales, in the mesoscale Weißeritz catchment as well as two selected subcatchments with different natural and urban conditions, the Weißbach subcatchment with a well-structured landscape, the Höckenbach subcatchment with a greater part of arable land. On the basis of selected scenarios, the effect of land use changes on the runoff generation processes of an area and on the hydrograph is described. Land use changes are able to reduce the portion of quick runoff components, the water erosion and the discharge. The effect occurs especially in smaller catchments and with short heavy rains (events with a frequency of occurrence of 5-50 years). Depending on the present situation the changes have to include areas of more than 25% of the catchments area to cause a significant effect. It became apparent that nature conservation and flood prevention agree well in their requirements with the land use. A rich structured landscape proved to be extraordinarily positive for both, flood prevention and nature conservation.

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.

This paper is focused on the Jizera Mountains as a region strongly influenced by man in the past. The structure of the natural forest was changed. Species monocultures with similar tree ages were planted. High acidificants concentrations in atmosphere led to the decline of these monoculture forests in the top parts of the mountains and the high acidificants deposition damaged the soils in the whole region. The goals of this study are to describe the distribution of the soil properties in altitude transects, where temperature, precipitation, and vegetation gradients are recorded, and to compare the soil properties in spruce and beech forests. The soil samples were collected from soil pits in a surviving nature-close beech forest, in a production spruce forest, and also in the top dead forest area with a grass cover. Soil samples from sufficiently deep diagnostic horizons were taken for the study of chemical properties. The basic soil characteristics were determined by the commonly used methods (pH, effective cation exchange capacity - eCEC, and the contents of cations in the sorption complex, A₄₀₀/A₆₀₀ as humus quality parameter, the contents of available Ca, Mg, K and P, pseudototal content of Ca and Mg, and two differently extracted Fe and Al forms contents). The soils of the Jizera Mts. are strongly acid with a low eCEC which is the result of the natural and anthropogenic acidification processes. Soil chemical properties of the most affected top mountainous parts are in some aspects more favourable than lower parts (binding of potentially toxic Al in organic matter, slightly higher pH), but in other aspects they are still endangered by the acidification symptoms (higher leaching of base cations, especially Mg). The soils of nature-close beech forests represent more favourable soil properties than those of planted spruce forests. Generally, it can be concluded that the natural systems have higher resilience, and that natural mechanisms are able to mitigate slightly the soil degradation.

Soil and water salinization are affecting an increasing number of countries in the world, especially in arid and semi-arid regions, and cause sensible reductions of agricultural land extension and of crop yields. Consociation with halophytic plants is a promising but not yet widely investigated strategy of salt stress reduction in crops. In this experiment, tomato plants were cultivated in saline conditions, alone and in consociation with three different halophytic species (Portulaca oleracea L.; Salsola soda L.; Atriplex hortensis L.). The salinity was brought either by the soil or by the irrigation water. Consociation with P. oleracea gave the best results in terms of increase of tomato growth and yields, while S. soda caused excessive nutritional competition against tomato due to its fast growth, undoing the positive effects of saline ions uptake. A. hortensis gave intermediate results. Salinity of water resulted in causing more severe stress on the plants, and consequently highlighted more the benefical effect of salt uptake performed by the halophytes on the main crop; salinity of soil on the contrary appeared to be less decisive, probably due to the leaching effect of the irrigation water.

The paper presents two approaches to the analysis of the impacts of landuse changes on hydrological regime in mountain catchments of northern Slovakia. An intersite comparison of measured data along the Jalovecký creek was used to test whether different landuse can be identified by means of water balance data and characteristics of runoff events. Although the comparison provided extended knowledge of the catchment, the only characteristic which might indicate possible impact of different landuse is the ratio of peakflow to flow at the beginning of the event. Simulations by means of spatially distributed hydrological model showed that different (extreme) scenarios resulted in relatively subtle impacts compared to uncertainties connected with hydrological modelling.

The role of the water movement and retention during extreme runoff formation was demonstrated in the Modrý Důl catchment (Krkonoše Mts., Czech Republic). A cyclone, which moved from Hungary to Poland, caused an extreme rainfall (120 mm) and subsequent extreme runoff in August, 2002. The precipitation, discharge, air and soil temperatures, tensiometric pressure, and soil moisture were recorded. The maximum retention capacity of the catchment was evaluated (70 mm). Depending on the actual retention capacity and the precipitation amount, two situations were recorded: (1) the precipitation amount lower than the actual retention capacity where the precipitation was fully absorbed in the catchment and the discharge in to the stream was not influenced by rain, (2) the precipitation amount higher than the actual retention capacity where the precipitation caused a saturation excess of the soil profile, generating extreme outflow into the stream. Neither the soil cover in the catchment or fluvial deposits along the Modrý potok stream were able to retain the extreme rain and inhibit the catastrophic flood.

Soils of reclaimed dumpsites after coal mining are considered as typical anthropogenic soils. These soils are at the beginning of their development and have certain specific characteristics. The aim of this study was to describe a soil survey performed on anthropogenic soils of a reclaimed dumpsite, to analyse spatial variability of selected properties using geostatistical methods, and to evaluate the development of reclaimed dumpsite soils. It has been shown that geostatistical methods are suitable for a description of anthropogenic soil properties and their variability. However, characterization of soil properties on the border between areas with different types of reclamation can be difficult due to sharp discontinual transitions caused by human activity. Properties of these soils vary profoundly greatly dependent on the properties of the soil substrate and the type of reclamation. The average content of organic carbon in the topsoil (0-20 cm) was 1.92% on the area covered with a layer of natural topsoil and 0.92% on the area covered by a layer of loess. An initial A horizon can develop even in 10 years under favourable conditions.

In the territory of the Czech Republic there are more than 50% of agricultural soils exposed to water erosion; it is a very urgent problem both at present and for the future. It must be solved now when there is still something to be protected. It is rather complicated to describe the soil properties in terms of soil susceptibility to water erosion because it is a complex relation in which many factors participate. For the complex evaluation of all main factors participating in erosion origination it is possible to apply the Universal Soil Loss Equation (USLE). It consists of six factors interacting with each other and participating in the origination of soil erosion. One of these factors is the soil erodibility factor (K-factor), the revision of which for soil conditions of the CR is the subject of this study. In total ca. 5000 soil pits from the whole territory of the country were processed and evaluated in detail. The main results of this study are K-factor values (means and variances) for the soil types, subtypes and varieties (represented in the database) according to the Taxonomic Classification System of Soils of the Czech Republic.

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

To determine specific characteristics necessary for the computation of the C factor in RUSLE for timevariable crops, measurements were carried out in fields with selected agricultural crops grown by conventional practices. Sloping plots on an experimental area in Třebsin locality and farm fields were used to measure surface runoff and soil loss by erosion in conditions of natural and simulated rainfall. Basic characteristics to compute the C factor were determined in the particular growth phases of selected crops - sunflower, flax, poppy and rape. Effective root mass, canopy cover and fall height of rain drops were measured.

In case that the climatic or farming conditions have changed in a region, it is possible to anticipate that the core parameters of drainage constructions will not be adequate for the current needs. Some of these constructions might be over-dimensioned, which would be inconsistent with current terms of nature and water resources protection. On the other hand, the valuable contribution the regulation of the water regime of originally waterlogged lands and swamps indisputably brought along and thus enabled the agricultural use of drained lands would be depreciated to a certain extent. In this paper, some scenarios of probable climatic changes in the Czech Republic's territory and the anticipated effect of these changes on the components of the hydrologic water discharge from drained agricultural and forest catchments are studied. The function of drainage systems on selected experimental lands is examined. However, not only probable changes in precipitation, temperature and water runoff should be taken into account, but also changes in the way of farming, i.e. changes in the agricultural conditions and data that played a decisive role in the calculation of the basic parameters of these construction projects, for instance, the spacing of parallel drains or trenches or the depth of their laying. In the Czech Republic about 1.1 million ha of total agricultural land was drained by the end of the twentieth century. In some localities of Eastern and Southern Bohemia up to 80% of agricultural land was drained. To what extent the above-mentioned climatic changes and the changes in the way of farming influence the drainage system and whether adjustments of these systems are required are the questions we tried to answer at least partly in this contribution. The effect of climatic changes on the hydrologic balance and/or on the runoff from the catchments significantly varies up to ± 150% provided that we compare average runoff. The influence of changes in the way of farming on the hydrologic balance manifests itself in a more concrete, but negative way, and that demands a concrete reaction on the part of the water management control. It is therefore vital to take such measures of regulation of the water regime of soil for the existing drainage systems that will ensure both the drainage phase and the phase of runoff retardation. Single-function and obsolete drainage systems should be converted into systems with controlled drainage and irrigation functions - the double-function control systems.

Anthropogenic soils are formed by human activities. The contents of potentially risk elements are one of the most important criteria of the exploitability of such soils for the agricultural production. The aim of this paper is to assess the contents of the selected potentially risk elements in 16 areas of the Sokolov region, including 5 reclaimed areas and 11 natural soils. 116 sampling locations were analysed in total. Another aim is to analyse the relationships between the elements, using multivariate statistical methods. The contents of the risk elements studied were in most cases under the limit values. In some cases, as with Pb, they were very low compared to the limit values. In the principal component analysis, four components explaining 74% of total variability were selected. The first component (30.2% of variability) showed strong correlations with Mn, V, Ni, and Cu contents. The second component (15.8% of variability) correlated with As and Be. The third component (14.3%) correlated with Pb and Cd. The fourth component (13.7%) correlated with Zn and Cr. The mean scores of each area were projected into the component plots, which enables the assessment of the relative importance of each group of elements in each particular area. The reclaimed and the natural soils are clearly distinguished. It can be concluded that the contents of the risk elements studied do not currently present any important problem in the reclaimed areas. Nevertheless, the situation should be further monitored.