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The effect of soil reaction on nickel and zinc availability to red clover has been determined through an analysis of 223 samples of soil and red clover collected in all communes of Cracow province. The content of total nickel in topsoil ranges from 2.8 to 50.0 mg/kg with a geometric mean concentration 15.2 mg/kg. The values for zinc are respectively 48.8-600 mg and 87.5 mg/kg. The amounts of metals assayed in the investigated clover samples are much smaller and they range for nickel from 0.4 to 16.3 mg/kg, on an average 2.3 mg/kg and for zinc 21.6-174 mg/kg, on an average 47.7 mg/kg d.m. The absorption of the investigated metals by clover depended not only on their content in soil but also on different soil properties, mainly its reaction. Relation between nickel content in clover and in soil has been expressed as a simple correlation coefficient - r=0.33 and r=0.20 for zinc. The relation has been more explicitly described by multiple regression equations which determine the metal content in clover based on its concentration in soil and soil pH or soil hydrolytic acidity.
The accumulation of heavy metals (Cd, Cu, Ni, Pb and Zn) by 19 plant species cultivated in the soil with natural content of those metals and contaminated with them was compared under pot experiment conditions. The elements were jointly applied into the soil as water soluble salts in a single dose (Me-1) and triple dose (Me-3). Cummulative capacity (on an everage) of all five studied heavy metals in the compared plants, irrespective of the metals contents in soil, raises in the following order: maize < oats < wheat < oil radish < ryegrass
Aura
|
2003
|
nr 04
4-5
Celebrating its 50th anniversary, the Academy is only the form of agricultural studies. The on-going studies in Poland at the Agricultural School of the Jagiellonian Universtity date back 1890. In 1923 the School became the Department of Agriculture. In 1919, the Forestry Department was formed as an independent part the University and in 1953 both Departments merged to become the Higher School of Agriculture, which, in 1972, was elevated to the rank of an Academy. It now comprises seven departmen agriculture and economy, forestry, animal husbandry and biology environmental engineering and geodesy, horticulture, agriculture technology and energy, and food technology. Environmental protection is the last year's addition.
Toxic effect of heavy metals (Cd, Cu, Ni, Pb and Zn) jointly applied into the soil as a single dose (Me-1) and triple dose (Me-3) on 19 cultivated plant species were compared under pot experiment conditions. A measure of toxic activity of the metals was a decrease in the plant yield as compared to the control object — without their addition to soil. Perennial ryegrass, wheat, oats, maize and hemp proved totally resistant to the applied metals. Buckwheat, sunflower, rape, oil radish, lettuce and beans were little sensitive, whereas phacelia, radish and onion were medium sensitive. In case of serradella, clover as well as spinach, parsley and red beets even a small dose of the metals applied to soil visibly inhibited their growth. Limiting of the above ground plant parts growth as a result of the heavy metals application occured simultaneously with a depression in the yield of their roots.
In June 1994 samples of soils and meadow plants were collected at 21 spots situated along the left bank of the Vistula within the Cracow province boundaries (Fig. 1). Two soil samples and one sample of meadow plants were picked between the embankment and the river-bed, as well as outside the flood bank al each spot. In all samples the contents of Cd, Cu, Ni, Pb and Zn were determined and also the basic physico-chemical properties of the soils. Turf soils in the Vistula valley within the Cracow province are highly diversified as to their basic properties and heavy metal contents (Tab. 1, Fig. 1 and 2). The highest accumulation of heavy metals and diversification in their contents are observed in the top layers of soils in the valley bottom zone adjoining the river-bed, separated by the flood bank. Total heavy metals contents range from 0.42 to 84.04 mg Cd, 87-2120 mg Zn, 7.5-181.4 mg Cu, 16.4-217.7 mg Pb and 15.4-60.7 mg Ni/kg d.m. Except for nickel, the level of examined heavy metals concentration in a majority of soil samples from this zone is described as serious or dangerous contamination (Tab. 3). Average content of investigated metals in the soils outside the embankment approximate to the contents most commonly noted in I tic arable lands in Cracov province. The contents of cadmium, zinc and copper in the soils within the embankment in the lower regions of the Vistula below Cracow are on an average ca 2 times higher that in the upper region. An analogous raise in lead concentration is almost 1.7 times higher. Only nickel contents in the soils of these two regions are almost identical. Nearly all samples of meadow plants from the zone between the flood bank and river-bed and many picked outside the embankment contained excessive amounts of cadmium from the point of view of their fodder usability (Tab. 4).
The aim of the paper was to investigate if and to what extent mining and treating of zinc-lead ores (Bukowno Olkusz, Trzebinia) and emissions from other factories localized within Katowice province (Jaworzno, Dąbrowa Górnicza) influenced the level of heavy metals contents in soils and meadow plants of north-western regions of Krakow province. Samples of soil and meadow sward were collected in 1592 at twenty points located along die north-western boundary of Krakow province (Fig. 1). One sample of meadow sward and three samples of soil, from 0-10, 10-20 and 10-50 cm layers were collected at each point. Total contents of Cd, Cu, Ni, Pb and Zn were determined in each sample. Apart Front heavy metals, also basic soil properties were assayed in the soil samples. A majority of examined soils have shown increased contents of Cd, Pb and Zn, but only in single cases the pollution may be considered dangerous (Tab. I and 3). On the other hand, concentrations of Cu and Ni, with few exceptions, fall within the range of „natural" contents. The following top values have been accepted for soils with natural contents: Cd - 1, Cu - 20. Ni - 20, Pb - 30 and Zn - 100 mg/kg. In respect of their vertical distribution in the soil profile, the examined metals fall into two groups: one included Cu and Ni, which do not show differentiation within the soil profile; the second is composed of Cd, Pb and Zn whose contents decrease markedly along with depth (Fig. 2 and 3). Such distribution of those three metals shows an influence of factors of anthropogenic origin which are not connected with subsoil The assayed contents of heavy metals in meadow sward, except for cadmium, is within the norm assumed for fodder plants (Tab. 4). Cadmium contents in sward exceed the lop permissible limit - 0.5 mg/kg d.m. - in 65% of samples.
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