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Zabieg krótkoterminowej biomanipulacji ekologicznej zastosowany w trzech śródleśnych płytkich jeziorach

Czerniawski R., Sługocki Ł, Domagała J., Pilecka-Rapacz M.

Rocznik Ochrona Środowiska

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2015

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Tom 17, cz. 2

1207--1223

EN

A crucial factor affecting the rate of eutrophication is the characteristics of the catchment area of lakes. The most visible result of excessive eutrophication is rapidly deteriorating transparency of waters in the summer which is caused by rapid development of planktonic algae. Another symptom of this process is gradual overgrowth of water reservoirs and watercourses by macrophytes. Hence, in order to improve the quality of water in these lakes the renovation treatment is applied. Lakes restoration can be made in many ways: physical, chemical and biological. The chemical and physical methods of lakes restoration are invasive and controversial. However, one of the relatively not invasive methods of lakes restoration is ecological biomanipulation. The goal of biomanipulation is to reduce the concentration of harmful phytoplankton, by the stocking of predatory fish triggers a trophic cascade with decreases in the biomass of smaller-bodied fish, e.g. cyprinids, increases in the biomass of herbivorous zooplankton, and decreases in the biomass of harmful phytoplankton. In some cases plankton-eating fish have been removed directly by lake managers. In addition, the removal of bottom-feeding fish from shallow lakes leads to increases in rooted vegetation and increased water clarity as the rooted plants stabilize the sediments. This transition involves a trophic cascade, as herbivorous zooplankton increase in biomass and consume phytoplankton, but also involves the direct effects of rooted vegetation on sediment stability and nutrient cycling. The most frequent cause of fast eutrophication is the runoff of untreated sewage directly into the waters of lakes and rivers or the excessive runoff of biogenic compounds from agricultural catchment areas. Forest lakes because of far distance from agglomeration and agricultural areas are in lesser extent exposed on the human pressure. Generally, one unfavorable variable affected these lakes is angling pressure. Thus, due to the lack of pollution and the relative stabilization of the mid-forest lakes they are a good place to conduct the ecological biomanipulation. The aim of the present study was to determine the short-term biomanipulation effectiveness in three shallow forest lakes. Biomanipulation was performed by stocking in 2012 to these lakes a summer fry of pike (200 ind. ha-1) and zander (150 ind. ha-1). Before the biomanipulation (in 2011) a control study of physic-chemical parameters, ichthyofauna and zooplankton composition were made. After the biomanipulation (in 2014) the same control study were conducted. Before and after the biomanipulation period significant changes in values of physic-chemical variables were not observed. Similarly, a slight changes in ichthyofauna composition between these two period occurred. The roach and bream were the biomass dominants. Only the zooplankton composition obtained pronounced changes, but statistically not significant. The most visible differences in zooplankton abundance concerned cladocerans – group that the most affect the phytoplankton decreasing. After the biomanipulation abundance of cladocerans increased from 31% to 67%. According to the results, it can be concluded that the biomanipulation time in study lakes was too short to make significant changes. To get a better effect of biomanipulation a successive stocking with summer or autumn fry of pike and zander should be conducted, even in 1000 ind. ha-1. Finally, we can assume that in the forest, shallow, highly eutrophic lakes a biomanipulation with predatory fish may be sufficient for their effective restoration.

2

Methods Applied in Cyanobacterial Bloom Control in Shallow Lakes and Reservoirs

Pęczuła W.

Ecological Chemistry and Engineering. A

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2012

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Vol. 19, nr 7

795-806

EN

The eutrophication of freshwaters – including shallow lakes – has become a global problem in the 21st century. Cyanobacterial blooms belong to the most frequent effects of this phenomenon. Although the problem, as well as methods for control it, are known since the beginning of the last century, in the last 25 years we can observe an increasing number of publications concerning methods of bloom control. The paper gives a review of different methods (chemical, physical and biological) applied in cyanobacterial bloom control in shallow lake ecosystems, taking into account not only the effectiveness of the methods but also their impact on other water biocenoses.

PL

Jednym z globalnych problemów XXI w. jest eutrofizacja wód śródlądowych, w tym płytkich jezior, której częstym efektem są zakwity cyjanobakterii planktonowych. Problem zakwitów sinic znany jest co najmniej od początku poprzedniego stulecia, podobnie jak i sposoby walki z tym negatywnym zjawiskiem, jednak to w ciągu ostatnich 25 lat, wraz z rozwojem ekologii płytkich jezior, daje się zauważyć wzrost liczby publikacji na temat nowych metod kontroli zakwitów. W artykule przedstawiono przegląd różnorodnych (chemicznych, fizycznych i biologicznych), aktualnie stosowanych metod ograniczania nadmiernego rozwoju cyjanobakterii w płytkich zbiornikach wodnych uwzględniając zarówno ich skuteczność, jak i wpływ na inne biocenozy wodne.

3

Reduction of emissions using biomanipulations of activated sludge: Selected full-scale examples

Rönner-Holm S., Holm N.

Environment Protection Engineering

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2009

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Vol. 35, nr 3

41-51

EN

Innovative wastewater treatment processes and bioenergy production techniques were developed by means of artificial selection/biomanipulation processes. In this paper, we present some examples of advanced biomanipulation of full-scale wastewater treatment plants and biogas plant. To achieve different goals, e.g. reduction of sludge volume index, augmentation of sludge concentration in the reactor or/and improvement of nutrient elimination, five different innovative process engineering concepts have been developed, tested and applied.

4

Daphnia: model herbivore, predator and prey

Lampert Winfried

Polish Journal of Ecology

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2006

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Vol. 54, nr 4

607-620

EN

In the past 30 years, Daphnia has become a model organism in aquatic ecology. I review the changing concepts and paradigms in plankton ecology as reflected in the work on Daphnia. The availability of radiotracers favoured a new physiological approach that resulted in better energetic models and more reliable estimates of filtering rates. This led to deeper insights into the role of herbivore grazing on phytoplankton and microbial communities, and nutrient recycling. It provided a conceptual basis for general hypotheses on predictable seasonal successions (e.g. the PEG model). On the other hand, increasing knowledge about selective predation on zooplankton triggered population dynamic models and gave explanations for changing community structures. The Size-Efficiency-Hypothesis generated a framework for studies on trade-offs between competitive ability and susceptibility to predation. Daphnia was now in the centre of interaction-based concepts, being predator and prey at the same time. It was the backbone of practical applications of the theory in food-web manipulations. When ultimate factors came into the focus, Daphnia played an important role in explaining striking phenomena like diel vertical migration and cyclomorphosis. Its central position in food-webs, the unique propagation mode, easy cultivation and accessibility by molecular genetic methods made it a favourite object for studies in evolutionary ecology, concerning local adaptation, evolution of defences and life histories, induced phenotypic change, and genetic diversity. The large advantage of Daphnia over other biological model organisms is that its importance in pelagic freshwater systems is undoubtedly known. Hence there is a direct way of applying the results to ecological systems.

5

Eutrophication problems and their potential solutions in the artificial shallow lake Altmuhlsee (Germany)

Schrenk-Bergt Ch., Kraule D., Prawitt O., Lewandowski J., Steinberg Ch.

Studia Quaternaria

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2004

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Vol. 21

73-86

EN

Lake Altmühlsee in Middle Franconia, Germany, was constructed as part of a water transportation system and flooded in 1986 by River Altmühl. Supply of nutrient rich water resulted in a hypertrophic state characterized by low Secchi depth (<0.5 m in summer). Massive blooms of phytoplankton in summer were mainly caused by cyanobacteria (Aphanizomenon flos-aquae, Anabaena flos-aquae, Microcystis aeruginosa) and by chlorophytes (Oocystis ssp., Monoraphidium ssp., Planktosphaeria gelatinosa), respectively. Fish assemblage was characterized by the dominancie of planktivorous bream. Hence, zooplankton community mostly consisted of small-bodied cladocerans due to predation pressure by fish. Investigations of the phosphorus (P) cycle of Lake Altmühlsee revealed high P-turnover rates in the water body and at the immediate sediment-water interface, an outstanding importance of external P-load, and a minor importance of the internal P-load. The lake supports recreational and social functions which, however, are restricted due to the low water quality. Improvement of water quality is necessary to increase attractiveness. Our study presents some proposals for an effective and economically justifiable water quality management, especially, biomanipulation in accordance to the holder of the fishing rights and local establishment of macrophytes.

6

Experimental approach for studying interrelationships between macroarthropods, soil biota, decomposion rate of litter and organic matter accumulation in soil

Kajak A.

Polish Journal of Ecology

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2000

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Vol. 48, nr 4

263-269

EN

The paper presents experimental design applied to analyse the role of macroarthropods patrolling soil surface on decomposition rate of grass litter (Dactylis glomerata). In the experiment density of micro- and mesofauna and microbial abundance in mesocosms accessible (open - O) and not accessible (closed - C) for large arthropods was compared. Mass loss of litter, mineralization rate of carbon and nitrogen, humus acid storage in sandy substratum underlying litter was estimated also. Results are presented in several papers. Effect of exclosures on the intensity of surface patrolling by macroarthropods and on their density in mesocosms in also presented.