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1

Development of toxin-producing cyanobacteria during the water level manipulation in a shallow heavily modified lake

Solis M., Pawlik-Skowrońska B., Kalinowska R.

Oceanological and Hydrobiological Studies

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2015

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Vol. 44, No. 2

223--235

EN

The development of cyanobacteria and microcystin variation was studied during two years in response to periodical water-level regulation in modified Lake Tomaszne. Before the water entrance from a canal, the biomass of toxigenic cyanobacteria was 0.001-0.33 mg dm-3, the microcystin concentration was below 1 μg dm-3, and three variants of microcystins were detected. After the water entrance from the canal, the biomass of cyanobacteria increased to 1.3-7.1 mg dm-3 with the dominants Aphanizomenon gracile and Dolichospermum planctonicum. After the water discharge from the lake, Planktothrix agardhii reached the highest biomass (2.3-6.6 mg dm-3). During the mass development of toxigenic cyanobacteria, the total microcystin concentrations were mostly higher than 5 μg dm-3 and the number of MC variants increased. Both Pl. agardhii and D. planktonicum accounted for microcystin production. The higher NH4-N concentrations supplied with water from the canal supported the biomass increase of Nostocales, whereas Pl. agardhii mass development was due to the low light intensity and high TP concentrations. Our study revealed that the use of nutrient-rich waters for the water management in the hydromorphologically modified lake supported the persistent development of cyanobacteria species leading to increased amounts of MC and a higher number of their structural variants

2

Właściwości reologiczne klarownych soków: aroniowego i jabłkowego

Sitkiewicz I., Kalinowska R., Kamiński B.

Postępy Techniki Przetwórstwa Spożywczego

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2008

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nr 2

17-21

PL

W pracy wyznaczono parametry reologiczne klarownych soków aroniowego i jabłkowego o stężeniu pomiędzy 10 stopni a 70 stopni Bx w zakresie temperatury od 10 stopni do 60 stopni C. Badane soki były cieczami niutonowskimi a ich lepkość malała ze wzrostem temperatury i wzrastała ze wzrostem stężenia. Energia aktywacji przepływu lepkiego Ea dla soku aroniowego przyjmowała niższe wartości niż dla soku jabłkowego, a jej wartość była funkcją stężenia badanego soku i można było ją opisać równaniem wielomianu trzeciego stopnia lub wykładniczym. Zastosowane, znane z literatury modele matematyczne opisujące równoczesny wpływ temperatury / Stężenia na wartość współczynnika lepkości, nie dały zadowalających wyników zgodności z danymi eksperymentalnymi.

EN

In this work the rheological properties of clarified juices: chokeberry and apple with different soluble solid content (10-70 degree Bx) at range of temperatures 10-60 degreeC were studied. The examined juices behaved as Newtonian fluids and their viscosity decreased with an increase in temperature and increased with an increase in soluble solid content. The chokeberry juice showed slightly lower activation energy Ea than clarified apple juice. The effect of soluble solids on energy activation can be described by an polynomial or an exponential equations. The mathematical models known from the literature describing the combined effect of temperature and soluble solids content on juices viscosity has not given satisfactorily results oj the accuracy with experimental data.

3

Metal resistance of soil algae (Chlorophyta) occurring in post-flotation Zn/Pb and Cu-tailing ponds

Kalinowska R., Pawlik-Skowrońska B.

Polish Journal of Ecology

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2008

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Vol. 56, nr 3

415-430

EN

Algae as pioneer organisms are important in extreme environments. We isolated several green algae (Chlorophyta) from Zn/Pb- and Cu-enriched ground samples of post-flotation tailing ponds, containing 17200-18400 mg Zn kg[^-1], 3017-6566 mg Pb kg[^-1] or 1420 mg Cu kg[^-1]. The algae with different morphologies belonged to following classes: Chlorophyceae and Trebouxiophyceae. Their Zn-, Pb- and Cu- resistance in comparison with soil green algae (Chlorophyceae) isolated from the unpolluted control soil was evaluated under laboratory conditions on the basis of 96h-EC[50] (effective metal concentration which causes 50% inhibition of algal growth after 96 h exposure). Among isolated algae Dictyococcus cf. varians Gerneck em. Starr from the Zn/Pb-tailing pond was highly resistant both to lead (EC[50] 48 [my]M) and zinc (EC[50] 126 [my]M), but sensitive to copper (EC[50] 2 [my]M). Stichococcus minor Nageli and Chlamydomonas boldii Ettl from the Cu-tailing pond were resistant to copper (EC[50] 17.8 [my]M and 10 [my]M, respectively). Simultaneously, S. minor revealed co-resistance to Zn (EC[50] 251 [my]M), while C. boldii to Pb (EC[50] 38.9 [my]M). Geminella terricola J.B. Petersen (Chlorophyceae), isolated from the unpolluted control soil, revealed high sensitivity to the three metals (Zn-EC[50] 44.6 [my]M; Pb-EC[50] 10.2 [my]M and Cu-EC[50] 6.4 [my]M). Simultaneously, G. terricola accumulated intracellularly higher amounts of Zn (7.1 amol [my]m[^-3]) and Cu (5.5 amol [my]m[^-3]) than all the algae from the polluted ground samples (Zn: 1.2-6.4 amol [my]m[^-3] and Cu: 0.4-2.7 amol [my]m[^-3]). It also accumulated high amounts of Pb (6.0 amol [my]m[^-3]), but two-fold lower than D. cf. varians. Using cytochemical staining of metals dark pink Pb-rhodizonate complexes were detected in thick cell walls of the Pb/Zn-resistant D. cf. varians and in thick mucilage layers of the Cu/Pb-resistant C. boldii. However, in the Pb-sensitive S. minor Pb-complexes were detected inside deformed cells. Pink-orange Zn-dithizone complexes were mainly distributed inside the cells of the Zn-resistant D. cf. varians. The results obtained suggest that thick cell walls or envelopes may be partly responsible for the higher Pb-resistance of some studied algae. However, in the case of micro-nutrients like Zn or Cu other resistance mechanisms (biochemical / physiological) may be involved. It seems that algal species or ecotypes living in the grounds of metal post-flotation tailing ponds have been adapted to heavy metals present in their habitats and may be useful for remediation of such degraded environments.