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41.
The mechanisms for translocation of heavy metals from soil to epigeal mosses were investigated. The first mechanism was demonstrated
for 137Cs and involved the uplifting of the pollutant-containing dust from the soil, followed by the local secondary deposition on
surfaces of epigeal mosses and epiphytic lichens. The second mechanism involved the diffusion of metal cations from the soil
through water wetting the moss into the gametophyte. The mechanism was demonstrated by measuring the electric conductance
of wetted gametophytes with single ends immersed in solutions of Cu and Na salts. In addition, the concentrations of Cu and
Cd were compared in moss samples exposed to the natural soil and to the soil contaminated with the metals. The exposition
to the contaminated soil resulted in the statistically significant increase of metal concentrations in the gametophytes. 相似文献
42.
Mirosaw Krzemieniewski Mariusz Teodorowicz Marcin Debowski & Jarosaw Pesta 《Aquaculture Research》2004,35(6):568-573
The influence of a constant magnetic field with an intensity ranging from 0.4 to 0.6 T (Tesla) was determined on physicochemical parameters of water and on rearing of larvae of the European sheatfish Silurus glanis L. larvae. In the experiment, feeding brood of European sheatfish was reared in two groups. One was kept in tanks supplied with magnetically treated water. The second group was kept in tanks supplied with water without treatment with a magnetic field (control). The fish tanks were supplied with circulating river water. Rearing was conducted for 15 days at an initial stocking density for both groups of 8 fish per litre. The mean fish mass obtained was 0.46 g, and in the control group – 0.78 g (P<0.05). Stocking mortality was 19.1% in the tanks with a constant magnetic field, and 13.5% in the control group. No changes were observed in water phosphate, ammonium, organic compounds or chloride concentrations. 相似文献
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Song Yi-Gang Walas Łukasz Pietras Marcin Sâm Hoàng Văn Yousefzadeh Hamed Ok Tolga Farzaliyev Vahid Worobiec Grzegorz Worobiec Elżbieta Stachowicz-Rybka Renata Boratyński Adam Boratyńska Krystyna Kozlowski Gregor Jasińska Anna K. 《European Journal of Forest Research》2021,140(6):1323-1339
European Journal of Forest Research - Pterocarya fraxinifolia, native to the southern Caucasus and adjacent areas, has been widely introduced in Europe. In this study, we investigate the following:... 相似文献
46.
Tadeusz Adamski Jerzy Chełkowski Zygmunt Kaczmarek Maria Surma Halina Wiśniewska 《Euphytica》1997,93(2):169-172
Auto- and alloplasmic doubled haploid (DH) lines of barley were examined for susceptibility to Fusarium culmorum (W.G.Sm.) Sacc. (isolate KF350) seedling blight. Inoculated kernels were incubated at 20 °C in a chamber saturated to 100% RH a with 12/12 h dark/light cycle. Germination capacity, disease score on a 5-degree scale and root length were evaluated. The data were analysed statistically using three-factor analysis of variance. It was observed that the infection score of roots of DH lines with H. bulbosum cytoplasm was higher than that of their autoplasmic analogues. Length of infected seedling roots expressed as per cent of the control root length ranged from 81 to 56% in autoplasmic DH lines and from 60 to 48% in alloplasmic lines. These differences were statistically significant (at P = 0.01). It was evident, that H. bulbosum cytoplasm increase susceptibility of barley genotypes to Fusarium seedling blight. 相似文献
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Wyrwicz LS von Grotthuss M Pas J Rychlewski L 《Science (New York, N.Y.)》2004,303(5655):168; author reply 168