Scientific registration n o : 2587 Symposium n o : 25 Presentation: poster. OLEK Jolanta, FILIPEK Tadeusz

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1 Scientific registration n o : 587 Symposium n o : 5 Presentation: poster Content and uptake of cadmium and lead by spring under conditions of sewage application Contenu et consommation de cadmium et plomb par l orge de printemps après applications de boues d épandages OLEK Jolanta, FILIPEK Tadeusz Department of Agricultural Chemistry, University of Agriculture, Akademicka 5, - 95 Lublin, Poland INTRODUCTION The development of city agglomerations, as well as industrial activity cause the constant increase of the amount of produced sewage. The technologies used in sewage treatment plants do not allow the total elimination of biogenic, toxic substances, and heavy metals from the sewage []. In this aspect, the investigation of possibilities of purifying the sewage in the soil environment in plant watering and fertilising systems, could be a profitable solution and an alternative to expensive methods used in sewage treatment plants. Agricultural application of municipal, municipal-industrial and some industrial sewage as an important source of water and nutrients for crops production can also contribute to soil pollution with trace elements. Heavy metals that are permanently sorbed by organic, mineral and organic-mineral colloids in soil accumulative layers are especially dangerous for a soil environment. Soil pollution with these elements is of a great importance because it is a potential source of metals for plants and on thus it can be the reason of their accumulation in animal and human organisms due to particular trophic chain stages. The pot experiment, in which the influence of purified municipal sewage of Lublin on the accumulation of cadmium and lead in spring, is part of the research project including wide topics of municipal sewage treatment in an integrated system of crops cultivation. Previously published results on cadmium content in orchard grass, as well as on lead content in orchard grass, maize, and white mustard concerned only the accumulation of metals in the vegetative mass of the plant [4,5]. The analysis of the amount and uptake of cadmium and lead in grain and straw of and the accumulation of these metals in particular plant parts aims at estimating the possibilities of using purified municipal sewage waters for watering cereal plants cultivated on both, mineral and s.

2 METHODS Model pot experiment was carried out on mineral podzolic soil formed from light loamy sand and an organic peat one. The soil material was taken from the accumulative layer and it was placed in pots of 5dm 3 capacity. Pots contained 6kg of 7.7% humidity and 4.5kg of 53.6% humidity each. Organic soil consisted of 33% organic matter,.6% total N, 668.5mg. kg - easily hydrolysing N. It was of a neutral reaction, very high level of available phosphorus and very low contents of potassium and magnesium. Mineral soil contained.6% total N, 84mg. kg - easily hydrolysing N, medium level of available phosphorus, low - potassium and very low - magnesium. Studies were conducted during -year period of experiments. In 995 the tested plant was orchard grass cut three times during its vegetation and in spring 996 the spring was sown. It was then harvested at the stage of full maturity. After was sprouted, singled and left tested plants per pot, it was fertilised with purified municipal sewage. The scheme of the experiment consisted of the following s: A - control without fertilisation; B - sewage water in quantity of cm 3 /pot a day C - sewage water in quantity of cm 3 /pot a day D - mineral fertilisation (N, P, K, Mg) in quantity like in B E - mineral fertilisation (N, P, K, Mg) in quantity like in C F - mineral fertilisation (N, P, K, Mg) in optimum dose G - sewage water in dose of B + mineral fertilisation to F level H - sewage water in dose of C + mineral fertilisation to F level In every pot there was maintained the humidity at the level of 6% maximum water capacity supplementing with distilled water to the stable mass. Purified sewage for irrigation came from municipal sewage plant «Hajdów» in Lublin. The concentrations of heavy metals in dm 3 sewage were following: Pb <.5mg, Cd <.mg, Cu <.5mg, Zn <.mg. Levels of basic elements amounted in turn: mineral N - 3mg, soluble P-PO 4-4mg, total K - 3mg, total Mg - mg. Along with lower sewage dose ( B) during single vegetation period there were introduced (in g/pot):.36 - N,.48 - P,.36 - K and. - Mg. Along with higher sewage dose ( C) amounts of introduced components were two times higher. The mineral fertilisation used in a form of soluble salts: NH 4 NO 3, KH PO 4, KCl, MgSO. 4 7H O. Global dose of components (in g/pot) applied during one vegetation period for B amounted: N -.4, P -.5, K -.4, Mg -.4. Dried plants were mineralised in 5 C with NH 4 NO 3 addition. Ash obtained was dissolved in HCl of spectral purity with redistilled water solution (:). Cadmium and lead concentrations were estimated by atomic absorption spectrometry method (AAS) using Perkin Elmer B apparatus. On a ground of cadmium and lead level in plants as well as its dry matter yield the uptake of the element was calculated. Statistical estimation of crops was carried out after plant's harvest. The effect of experimental factors on yield was estimated using variance analysis with Tukey s intersections.

3 RESULTS Average value of cadmium and lead amount in spring from particular soils and s is shown in Figs.- and 5-6. Higher concentration of cadmium was stated in plants cultivated in (grain.57 mg/kg, straw.9 mg/kg). In the values were: grain.9 mg/kg, straw.4 mg/kg). In grains of cultivated on the in s (E, F, G, H), in which only the mineral fertilisation or fertilisation with sewage supported by mineral fertilisation were used, the content of cadmium was several times higher then in similar s on the. Grain of cultivated on the had much higher average content of cadmium then straw, while on the its higher content was stated in the straw. The results are supported by the literature data. Cadmium is intensively accumulated in root tissues, it is easily transported in the plant and it is supplied to all parts of the plant []. As opposed to other metals it also easily enters to generative parts of the plant [, 3, 6]. Lead reached almost 3 times as much of a concentration in straw, despite of the soil kind. Also other authors [3], while investigating the concentration of Pb in cereals, stated that twice as much of that element was in the straw, comparing to grain. There was stated that the content of Pb in spring cultivated on the soil highly polluted by Zn-Pb flue dust smelter was 3 times higher in grain then in the straw [6]. The used experimental factors caused high differentiation of lead concentration in particular treatment s. Higher average amount of lead, opposite to cadmium, was in the plants cultivated on (grain.6 mg/kg, straw.76 mg/kg), comparing to (grain.5 mg/kg, straw.69 mg/kg). Lead is a metal, which transportation to the upper part of a plant is difficult because of the mechanisms of immobilisation in the form of metal-protein complexes and precipitation of insoluble salts in roots. Plant cultivation on light strongly acidified soils, however, positively influences the lead uptake and transporting to upper parts of plants []. The influence of purified municipal sewage, as well as mineral fertilisation on the content of cadmium in straw was small. Also an insignificant increase in the content of cadmium occurred in s G and H, as compared to the control, in which the sewage was used in single and double doses supplemented with mineral fertilisation. Purified municipal sewage did not significantly influence the content of cadmium in grain. Considerable increase of that element in grain appeared in s on, in which only mineral fertilisation (E, F) or both fertilisation methods had been used (G, H). The s with fertilised with mineral fertilisers (D, E, F, G) showed the cadmium content decreased by half as compared to the control. Purified municipal sewage did not affect the increase of lead concentration in grain, while in straw only in one (F) a clear influence of mineral fertilisation on lead content was observed in both, the mineral and the. The cadmium and lead uptake as the function of plant biomass (Table ) and the concentration of the element in the plant are shown in Figs.3-4 and 7-8. Purified municipal sewage did not influence the increased uptake of cadmium and lead by spring. Plant biomass mainly decided upon the uptake of those metals. The highest amounts of the taken-up cadmium were found in grain in s E, F, G, and H on the. Both, high concentration of that metal in grain and the high yield of grain influenced the uptake value. 3

4 In straw, the greatest amounts of cadmium uptake were found in s, in which sewage supplemented by mineral fertilisation were used (G, H). The plants from those s contained high concentrations of the metal in straw and had the highest biomass. Barley straw had several times higher accumulation of lead than grain, which had been caused mainly by higher concentration of lead in straw than in grain. Table. Effect of purified municipal sewage on yield of spring [g d. m./pot] Grain Straw Object* Mineral soil Organic soil Mineral soil Organic soil A B C D E F G H LSD(p=,) X**.54.5 Y**.5.43 XY.39.5 * - symbols like in experiment scheme enclosed; ** - X soil type; Y CONCLUSIONS. High content of cadmium stated in grains, especially in (grain.57 mg/kg, straw.9 mg/kg) proves the very easy transportation of this metal to the generative parts of plants.. Much smaller content of lead in grain that in straw concurs the activity of the mechanism of immobilisation of this metal in the vegetative parts of plants. 3. Cadmium accumulation in straw mostly depended on the biomass not the content of Cd, the amount of which was steady, despite of the fertilisation method and the kind of soil. 4. No influence of purified municipal sewage on the increase of the concentration and the uptake of the investigated metals by spring was stated. REFERENCES. Bary³a R., Harkot W., 997: The content of cadmium in some grass species irrigated with purified municipal sewage. Zesz. Probl. Post. Nauk Roln. 448a, p

5 . Kabata-Pendias A., Pendias H., 993: Trace elements in biological environment. Wydawnictwa Geologiczne, Warszawa, 979, p Kucharzewski A., DŒbowski M., 996: Estimation of pollution with heavy metals and sulphur of crops in Lower Silesia. - Zesz. Probl. Post. Nauk Roln. 434, p Olek J., 997: Accumulation of cadmium in test plant as an effect of applying purified sewage of Lublin. - Zesz. Probl. Post. Nauk Roln. 448a, p Olek J., 997: Lead accumulation in tested plants under conditions of purified municipal sewage in Lublin. - Proc. of the Intern. Symp. at The University of Miscolc, -7 Aug. 997, p Piotrowska M., Kabata-Pendias A., 997: Levels of Cd, Zn and Pb in selected food plants grown in soils contaminated with Zn - Pb smelter dust. - Proc. of the Intern. Conf. at The University of Mining and Metallurgy, Kraków, - Nov.997, p Key words : cadmium, lead, plant, sewage Mots clés : cadmium, plomb, plantes, boues mg/kg Fig.. Effect of purified municipal sewage on the content of cadmium in the grain of spring (mg Cd/kg).,,8,6 Fig.. Effect of purified municipal sewage on the content of cadmium in the straw of spring (mg Cd/kg)., mg/kg,8,6,4,4,, µg/ pot Fig. 3. Effect of purified municipal sewage on the uptake of cadmium by the grain of spring (µg Cd/pot). µg/pot Fig. 4. Effect of purified municipal sewage on the uptake of cadmium by the straw of spring (µg Cd/pot). 5

6 mg/ kg Fig. 5. Effect of purified municipal sewage on the content of lead in the grain of spring (mg Pb/kg). 3,5 3,5,5,5 A B C D E F G H mean Fig. 6. Effect of purified municipal sewage on the content of lead in the straw of spring (mg Pb/kg). 3,5 3 mg/ kg,5,5,5 µg/pot Fig. 7. Effect of purified municipal sewage on the uptake of cadmium by the grain of spring (µ g Pb/pot) Fig. 8. Effect of purified municipal sewage on the uptake of cadmium by the straw of spring (µ g Pb/pot). 9 µg/pot