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The reserve root nutrients influence the overwintering, regrowth, yield, and persistence of alfalfa plants. The total amount of the root reserves is considered more important than their concentration. One of the factors which can affect the reserve content can be the soil compaction. The aim of this study is to clarify the effect of the soil compaction on the reserve root nutrients in relation to the stand density and the amount of the root biomass. In this experiment, the stand density ranged from 28 to 112 plants per m². The average soil bulk density in the uncompacted and compacted variants was found to be 1.38 and 1.52 g/cm³, respectively. In spring and autumn periods, the root samples were taken from an area of 0.25 m² (the depth 150 mm) in four replications. The number of plants, the root weight, and the concentrations of starch, saccharose, fructose, and crude protein were assessed in each plot. The total amount of the root reserves was calculated from the determined concentrations and the weights of roots of each sample. A higher soil compaction reduced significantly the stand density, root weight, total amount of all nutrients as well as the starch and crude protein concentrations. The concentration of the soluble non-structural saccharides was identical to or increased over that in the compacted variant. The negative significant effect of a higher soil compaction on the root weight and, consequently, on the total amount of all reserve root nutrients was explained by the changes in the stand density. When the root weight effect was excluded, the compacted variant provided a significantly lower density and crude protein amount and concentration. The significant effect of density on the reserve nutrients was explained by changes in the root weight.

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.

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.

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.