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1

How artificial aeration improved sewage treatment of an integrated vertical-flow constructed wetland

100%
Tao M., He F., Xu D., Li M., Wu Z.
Polish Journal of Environmental Studies
|
2010
|
tom 19
|
nr 1
183-191
Artificial aeration was added to an integrated vertical-flow constructed wetland (called aerated IVCW hereafter) for improving water purification performance. The results showed that both oxygen levels and aerobic zones were increased in the wetland substrates. The electric potential (Eh) profiling demonstrated that artificial aeration maintained the pattern of sequential oxic-anoxic-oxic redox zones within the aerated IVCW chambers in winter, while only two oxic-anoxic zones were present inside the non-aerated IVCW in the cold seasons. The nitrification/denitrification processes and organic matter decomposition were enhanced by artificial aeration since the removal efficiency of NH₄⁺-N and BOD₅ were significantly improved in all seasons, particularly in winter. It seemed that artificial aeration could compensate for the absence of plant-mediated oxygen supply, though the low temperatures and plant dieback still affected the removal efficiency of COD and TN in the winter. Eight hours of artificial aeration per day was sufficient to eliminate the significant accumulation of NO₃⁻-N previously observed in the effluent from continuously aerated subsurface-flow constructed wetlands. These results suggest that the aerated IVCW could treat domestic sewage more efficiently, especially in winter.
2

Possibilities of a saprotrophic lake recultivation exemplified by Lake Dlugie in Olsztyn

100%
Gawronska H., Lossow K.
Polish Journal of Environmental Studies
|
2003
|
tom 12
|
nr 3
This article presents the subsequent stages of Lake Długie recultivation. The lake has been completely degraded and has reached a saprotrophic state due to the discharge of domestic wastewater from the neighbouring living estate. The lake’s recultivation was initiated by cutting off the domestic wastewater inflow to the lake, and followed by the reduction of storm water inflow and artificial aeration with destratification carried out with modifications since 1987. Special attention was paid to the effects obtained in the reference years (i.e. without aeration) which allows determination of the durability of the recultivation results.
3

Attempts to use wind energy for artificial destratification of Lake Starodworskie

100%
Lossow K., Gawronska H., Jaszczult R.
Polish Journal of Environmental Studies
|
1998
|
tom 07
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nr 4
Attempts at lake restoration by artificial aeration with the use of wind energy were made on the heavily eutrophic Lake Starodworskie. The lake is small - only 7 ha surface area but deep - 23 m. Artificial aeration was performed by destratification method. Compressed air, produced with the help of a wind turbine was subsequently delivered to the deepest site in the lake. As show the study results from 1985-87, the effects of the applied method were limited. Breaks in aeration caused by lack of winds or too low windpower prevented full destruction of thermal and chemical stratification. However, in the hypolimnion some temperature increase was observed, and oxygenation improvement - minor in summer and considerable in the other seasons. Moreover, the content of organic compounds and nutrients (especially phosphorus) decreased.
4

The influence of a long-term artificial aeration on the nitrogen compounds exchange between bottom sediments and water in Lake Dlugie

84%
Brzozowska R., Gawronska H.
Oceanological and Hydrobiological Studies
|
2009
|
tom 38
|
nr 1
113-119
5

Possibilities to reduce internal loading to lake water by artificial aeration

84%
Gawronska H., Brzozowska R., Grochowska J., Lossow K.
Polish Journal of Environmental Studies
|
2003
|
tom 12
|
nr 2
The influence of artificial aeration on chemical composition of bottom sediments and nutrient exchange was investigated in heavily polluted Lake Długie. Analyzed were variations in the content of nitrogen and phosphorus compounds in near-bottom water, interstitial water and bottom sediments. The obtained results have confirmed a positive role of many years’ artificial aeration in reducing the internal loading of nutrients. At the current stage of the survey, it is not possible to determine explicitly whether artificial aeration has had an effect on the chemical composition of bottom sediments.
6

Restoration effectiveness of a degraded lake using multi-year artificial aeration

84%
Grochowska J., Gawronska H.
Polish Journal of Environmental Studies
|
2004
|
tom 13
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nr 6
Lake Długie in Olsztyn, Poland, received untreated sewage for over 20 years from a housing estate which probably caused its complete degradation. The lake was regarded in the 1970s as one of the most polluted in Poland; its chemical composition was similar to that of diluted sewage. After the sewage diversion, the amount of organic compounds and nutrients in the water diminished, although the aquatic environment conditions did not improve considerably. Improvement of the trophic state of the lake might have been expected only after applying a relevant restoration technique. Our paper presents the results from a study of the effectiveness of a multi-year restoration of Lake Długie, using the artificial aeration method with destratification. Analysis of the obtained results supports the conclusion that the more than 10-year artificial circulation has resulted in a radical improvement of the environmental conditions in the lake displayed by: increase of oxygen content in the whole water volume, reduction of its consumption rate during both stagnation periods, shortening of the anoxia period in the near-bottom waters, and increase of the redox potential. The artificial aeration has caused a radical decrease of nutrients and organic compounds content in the water, and eventually improved the trophic state. Concentration of phosphorus compounds in the water was reduced mainly due to halted release of the phosphate phosphorus from the bottom sediments. In the case of nitrogen compounds, halted release from the bottom sediments, intensification of the nitrification processes but mainly due to the denitrification process. Despite the considerable reduction of nitrogen and phosphorus compound concentrations in the lake waters, the applied treatment has not resulted in sufficient reduction of the nutrients as to limit the primary production. The lake had remained a heavily eutrophic reservoir which was confirmed by still high values of BOD5, chlorophyll a and low transparency measured by Secchi disk. In the following years of artificial aeration a drop in the reduction rate of the phosphorus compound concentrations was observed which at the parallel lack of iron and manganese in the water indicates that in the case of Lake Długie the capacity for further improvement of its trophic condition in this way had been practically exhausted. Better effects may be expected only after the application of a supportive method, consisting of phosphorus precipitation and fixing in the bottom sediments.
7

Sanitary and bacteriological survey of an artificially aerated eutrophic Lake Starodworskie, Poland

84%
Niewolak S., Chrzanowska L., Golas I., Pijorek A., Sadurska J.
Polish Journal of Environmental Studies
|
1997
|
tom 06
|
nr 6
This paper presents the results of sanitary and bacteriological analyses of water and bottom sediments of an artificially aerated eutrophic Lake Starodworskie, Mazurian Lakeland, performed in 1986-1988. Analyses of water (in a vertical and horizontal profile) and of bottom sediments (from the 0-5 cm layer) were performed on five stations; samples were collected at monthly intervals: in 1986 when aeration was of low density; in 1987, when it was intensive; and in 1988, under the ice cover. The following indices were determined: TVC 20°C, TVC 37"C, TC, FC and FS. Numbers of micro-organisms belonging to these groups in water and bottom sediments were different in 1986 and 1987 and related to the intensity of aeration, distance from the lake shore, depth, and season, and atmospheric conditions. Bacteriological purity of water and bottom sediments was defined based on the usual water quality criteria, water suitability for recreational use, lake loading with organic matter easily decomposed by bacteria, and its loading with pollutants originating from humans and animals. The results suggest that the majority of water samples were clean or only slightly polluted, and loading of lake sediments with easily decomposed organic matter was relatively low, but they were fairly polluted with animal faeces. Pollution of water and of bottom sediments was higher in the first year of aeration than in the second one.
8

Influence of a multi-year artificial aeration of a lake using destratification method on the sediment-water phosphorus exchange

67%
Brzozowska R., Gawronska H.
Archiwum Ochrony Środowiska
|
2005
|
tom 31
|
nr 3
9

Odzywianie sie dominujacych gatunkow ryb w sztucznie napowietrzanym jeziorze Mutek

59%
Martyniak A.
Acta Academiae Agriculturae ac Technicae Olstenensis. Protectio Aquarum et Piscatoria
|
1993
|
tom 19,Suppl.B
46
10

Wymiana fosforu i azotu miedzy osadami a woda w jeziorze sztucznie napowietrzanym

51%
Gawronska H.
Acta Academiae Agriculturae ac Technicae Olstenensis. Protectio Aquarum et Piscatoria
|
1994
|
tom 19,Suppl.E
50
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