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An overview of the distribution and ecology of the alien cyanobacteria species Raphidiopsis raciborskii, Sphaerospermopsis aphanizomenoides and Chrysosporum bergii in Europe

Šuikaitė Izabelė, Vansevičiūtė Gelminė, Koreivienė Judita

Oceanological and Hydrobiological Studies

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2023

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Vol. 52, No. 3

312--332

EN

Cyanobacteria can form blooms and pose a threat tothe functioning of freshwater ecosystems. Cyanobacterial invasions are expected to increase due to climate change. Alien species cause a decline in biodiversity by displacing native species, lead to extinctions, affect food webs,and produce cyanotoxins which potentially impact theenvironment and human health. Three species, Raphidiopsis raciborskii, Sphaerospermospis aphanizomenoides and Chrysosporum bergii, are considered non-native to European waters. Recently, they have expanded their native habitats and become established in temperate lakes. In this article, we provide a detailed overview of the countries where they are distributed and the occurrence of the blooms in Europe. We discuss the biotic and abiotic environmental factors that influence their establishment, as well as the characteristics of the species that make them so adaptable in non-native habitats. Understanding the interplay of these factors willallow us to better recognise patterns of invasiveness and predict their future threats to ecosystems.

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The valley-fill deposits of the Kłodnica River (Southern Poland) : environmental drivers of facies changes from the Late Vistulian through the Holocene

Wójcicki K. J.

Geochronometria

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2010

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Vol. 35

49-66

EN

Lithological analyses and radiocarbon dating were used to elucidate the patterns and controls of Late Quaternary valley floor development of the Kłodnica River, the Upper Odra Basin. The research results were discussed with data obtained from valleys of rivers draining piedmont basins and highlands of southern Poland. In consequence, five stages of morpho-sedimentary evolution of the Kłodnica valley were distinguished. In the Late Vistulian a large-scale deposition of channel alluvium took place in the conditions of high river discharges. This sedimentary style probably still existed in the Early Pre-Boreal as long as open grass communities survived in the Kłodnica catchment. The next phase, in the Late Pre-Boreal and Boreal, is characterized by a significant increase in accumulation rate of biochemical facies.. The considerable restriction of minerogenic deposition was connected with widespread of forest and gradual limitation of the river discharges. The third stage began at the decline of the Boreal and was defined by decrease of accumulation rate or even biogenic accumulation break. Synchronously, periodic increases of fluvial activity were noticed in the form of cutoffs of meander loops and overbank deposition in oxbows. The beginning of the fourth period took place not earlier than in the Early Sub-Boreal. This stage was distinguished by renewed peat growth/increase in biochemical accumulation rate and periodic increase in alluviation, generally taking place in the conditions of low channel-forming flows. The latest phase (from the Middle Sub- Atlantic till now) is characterized by common initiation of slope deposition and a rapid increase in fluvial sedimentation, especially overbank and tributary fan facies. An increase in minerogenic deposition occurred in response to human impact, which became more significant from the Roman Period and occurred on a large scale from the early Middle Ages. Older settlement phases, including intense settlement from the Hallstatt Period, were not clearly recorded in the Kłodnica valley fill.

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Practical applications of the multi-component marine photosynthesis model (MCM)

Ficek D., Majchrowski R., Ostrowska M., Kaczmarek S., Woźniak B., Dera J.

Oceanologia

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2003

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No. 45 (3)

395-423

EN

This paper describes the applications and accuracy analyses of our multi-component model of marine photosynthesis, given in detail in Woźniak et al. (2003). We now describe an application of the model to determine quantities characterising the photosynthesis of marine algae, especially the quantum yield of photosynthesis and photosynthetic primary production. These calculations have permitted the analysis of the variability of these photosynthesis characteristics in a diversity of seas, at different seasons, and at different depths. Because of its structure, the model can be used as the "marine part" of break a "satellite" algorithm for monitoring primary production in the sea (the set of input data necessary for the calculations can be determined with remote sensing methods). With this in mind, in the present work, we have tested and verified the model using empirical data. The verification yielded satisfactory results: for example, the statistical errors in estimates of primary production in the water column for Case 1 Waters do not exceed 45%. Hence, this model is far more accurate than earlier, less complex models hitherto applied in satellite algorithms.

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Predation and the dynamics of the bank vole, Clethrionomys glareolus

Oksanen T., Oksanen L., Jędrzejewski W., Jędrzejewska B., Korpimäki E., Norrdahl K.

Polish Journal of Ecology

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2000

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Vol. 48, Suppl.

197-217

EN

Theoretical analyses and data suggest that the interaction between bank voles and their predators generates a locally stable equilibrium, regardless to the composition of the predator guild. The suggested primary proximate source for stability is female territoriality. Predation_per se_appears to be destabilizing. Whether or not predation regulates bank voles appears thus to be a semantic issue, depending on the operational definition of the concept of regulation. Confusion has arisen as different operational definitions have been tacitly used by different authors. The predicted intrinsic stability of bank vole-predator systems is most clearly displayed in the southern part of the boreal zone. Currently, even the dynamics of bank voles of taiga landscapes in Finnish ?apland are close to the predicted multiannual stability. In those boreal areas, where grassy and productive Microtus habitats are relatively abundant, sustained, multiannual cycles appear to be generated by the interaction between small mustelids and Microtus spp. When desities of Microtus decline, fidelity to Microtus habitats becomes suboptimal for predators. Consequently, cyclicity seems to be externally imposed on bank voles, due to changing habitat preferences of predators during the course of the mustelid-Microtus cycle. In the temperate zone, masting (seed crops of deciduous trees) increases the reproductive rate of bank voles and ameliorates female territoriality, initiating a transient increase in the numbers of bank voles and their predators. Beforethe system reaches its new equilibrium, the mast is over. Due to the combined effect of high predator numbers and normal reproductive performance, bank vole numbers then decline to the low level typicalfor post-mast years. Depending on the frequency of masting, the post-past low can be followed by a stable phase or immediately by a new mast-triggered outbreak. Although fundamentally different mechanisms appear to account for multiannual density fluctuations in temperate and boreal bank vole populations, both phenomena can be interpreted as consequences of extremal perturbations upon intrinsically stable predator-prey systems.