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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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Annual cycle of phytoplankton community through the water kolumn : study applied to the implementation of bivalve offshore aquaculture in the southeastern Bay of Biscay

Muñiz Oihane, Revilla Marta, Rodríguez José Germán, Laza-Martínez Aitor, Fontán Almudena

Oceanologia

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2019

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No. 61 (1)

114--130

EN

This study describes, for the first time, the annual variability of phytoplankton community in different layers of the water column in open waters off the Basque coast (southeastern Bay of Biscay). Phytoplankton composition, abundance and biomass, together with size-fractionated chlorophyll a, nutrients, and optical and hydrographic conditions were measured in an experimental bivalve culture area from May 2014 to June 2015. Water kolumn conditions showed the typical dynamics previously described for temperate areas, characterised by winter homogeneity and summer stratification. Phytoplankton temporal variability was studied at depths of 3,17 and 33 m, and was found to be related to those processes. In particular, temperature and nutrients (mostly nitrate and silicate) were the environmental variables which significantly explained most of the variability of chlorophyll concentration, whereas river flow was the main driver of abundance variability. Total chlorophyll was generally low (0.6 μg L-1 on average). Of the 194 registered taxa, 47.4% belonged to dinoflagellates and 35.1% to diatoms. In addition, diatoms showed the highest biomass values, and haptophytes represented the greatest expericontribution to cell-abundance. This fact, despite the low chlorophyll values indicating low phytoplankton biomass, could favour mussel growth given the high fatty acid content reported for diatoms and haptophytes.

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Cyanobacteria Dynamics in a Mediterranean Reservoir of the North East of Algeria: Vertical and Seasonal Variability

Touati Hassen, Guellati Fatma Zohra, Arif Salah, Bensouilah Mourad

Journal of Ecological Engineering

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2019

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Vol. 20, nr 1

93--107

EN

Harmful cyanobacterial efflorescence is of growing global concern and its prediction and management require a better understanding of the growth control factors and dominance of cyanobacteria. The Zit-Emba reservoir located in the North-East of Algeria, was constructed to provide drinking water, irrigation, and fishing. The vertical and seasonal distribution variation of cyanobacteria community associated with environmental factors was comprehensively investigated from April 2016 to December 2016 at five depths, based on a seasonal sampling. The cyanobacteria communities of this reservoir are composed of seven genera belonging to five orders. The average proportion of Microcystis to total cyanobacteria population was 43%, followed by Woronichinia 21%, Planktothrix 16%, Dolichospermum 13%, Oscillatoria 5%, and the remainder (Merismopedia, Spirulina) 2%. The average cyanobacterial abundance was 2702 cells/mL, ranging from 360 to 65 795 cells/mL and this abundance exceeds the alert level 1 throughout the year. The most recurrent periods of increase took place from spring to summer and autumn. However, the vertical distributions of cyanobacteria displayed a similar profile each season, and abundances tended to decrease with depth. The results of the statistical analysis suggested that the most abundant of cyanobacterial genera were positively related to chlorophyll-a and water temperature and negatively with the concentrations of NO3-N, NH4-N, and NO2-N. This demonstration of toxigenic cyanobacteria in this drinking water production dam involves regular monitoring of the cyanobacterial communities and cyanotoxins in raw water.

4

Epiphytic Lichen Diversity as Indicator of Environmental Quality in an Industrial Area (Central Lithuania)

Sujetovienė G.

Polish Journal of Ecology

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2017

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Vol. 65, nr 1

38--45

EN

The objective of the study was to evaluate the impact of nitrogen fertilizer industry pollution on epiphytic lichen communities. The study plots are located in Scots pine Pinus sylvestris stands at different distances (up to 12 km) to the northeast and southwest of the nitrogen fertilizer producer plant in central Lithuania. The stands were semi-mature and mature and growing on sandy sites of the Vaccinio-myrtillosa site type. Species richness, composition and index of atmospheric purity (IAP) were assessed at each site. Species diversity was calculated by grouping species by their ecological values for eutrophication. Species frequency was calculated according to lichen life strategies (growth forms, photobionts, reproductive strategies). Twenty lichens species were recorded in the surrounding of the pollution source. An increase in species richness and diversity was found with increasing the distance up to 10 km from the plant. Based on IAP values three zones (< 5, 5–10, > 10 km) with different air pollution were distinguished. The increase in species richness was related to the increase in eutrophication-tolerating species along with sensitive to pollution species. The lichen diversity value of nitrophytic species (LDVnitro) increased with increasing distance from the pollution source. Foliose and fruticose growth forms were both positively significantly related with the distance, being common in the plots with lower level of pollution. Crustose lichens are less sensitive to this factor and the prevalence of crustose thalli was found in the nearest vicinity to the plant.

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Potential effects of abiotic factors on the abundance and distribution of the plankton in the Western Harbour, south-eastern Mediterranean Sea, Egypt

Heneash A. M. M., Tadrose H. R. Z., Hussein M. M. A., Hamdona S. K., Abdel-Aziz N., Gharib S. M.

Oceanologia

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2015

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No. 57 (1)

61--70

EN

Samples were collected seasonally from Western Harbour during winter 2012–winter 2013 to examine spatial and temporal variability in phytoplankton and zooplankton abundance in relation to physicochemical parameters. Water was alkaline and well oxygenated. Nutrient concentrations were generally high and related to inflow of discharged waters. A total of 157 and 106 of phytoplankton and zooplankton species were recorded, respectively. The average plankton population was 4 × 106 cells l-1 in terms of phytoplankton and 24 × 103 ind. m-3 in terms of zooplankton. Seasonal differences in the quantitative and qualitative composition of both communities in the different stations were marked. Eutreptiella belonging to class Euglenophyceae overwhelming during spring, reaching an average of 17 × 106 cells l-1. The genus previously was recorded as rare form in the Egyptian waters and may have been introduced via ballast water. Except in spring, copepods were the most abundant group and tintinnid abundances generally increased in spring. The ranges of Shannon diversity indices indicate disturbance level and sometimes high productivity. Salinity, dissolved oxygen and pH may be responsible for the variations in phytoplankton and zooplankton community structure. The results indicate that not only the discharged water make the harbour at risk, but also the ballast water is not less dangerous, and so, we emphasize the need for activation of the ballast water management IMO Ballast Water Management Conventions to reduce the risk of future species invasions.

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Predicting current and future invasion of Solidago canadensis; a study from China

Xu Z., Peng H., Feng Z., Abdulsalih N.

Polish Journal of Ecology

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2014

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Vol. 62, nr 2

263--271

EN

Solidago canadensis, which is native to North America, is considered to be the most widespread invasive alien plant. The invasion of Solidago canadensis in China has resulted in serious environmental problems. Therefore, understanding the relationship between the geographical distribution of S. canadensis and bioclimatic variables, and then predicting the potential distribution of this species is essential for management actions and practices. Although several studies have delineated the potential distribution of S. canadensis in China, how this species would respond to variations in future climatic conditions remains unclear. In the present study, we predicted the potential distribution of S. canadensis under current and future climatic conditions using species distribution models. We also analyzed range shifting of this species under current and future climatic conditions. We arrived at several conclusions. First, the potential distribution of S. canadensis may expand 40% under future climatic condition compare with that of under current condition. Second, mean diurnal range, isothermality, mean temperature of the wettest quarter, mean temperature of the warmest quarter, precipitation of the driest month, and precipitation seasonality (coefficient of variation) are key bioclimatic variables in determine the potential distribution of S. canadensis. Third, expansion of S. canadensis can be partly attributed to the relatively warmer and wetter future bioclimatic condition than current one.

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Evaluation of the effect of environmental variables on health condition of Quercus robur L. in parks

Krzyżaniak M., Świerk D., Urbański P., Walerzak M. T.

Ecological Chemistry and Engineering. S

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2013

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Vol. 20, nr 4

689--700

EN

Investigations concerned the effect of different environmental variables on health condition of English oak (Quercus robur L.). It was shown that in the public parks in the city of Poznan the health condition of the analysed species is good. It was stated that health condition of this species in the Poznan parks is influenced by the distance from the immediate city centre, vicinity of traffic arteries and gas emissions from the combustion of fossil fuels by households neighbouring with the parks. Although results recorded in this study confirm literature data concerning the effect of environmental variables on health condition of English oak (Quercus robur L.), it was shown that certain environmental variables have a greater effect on health condition of the analysed species in Poznan.

PL

Badania dotyczyły wpływu różnych zmiennych środowiskowych na stan zdrowotny dębu szypułkowego (Quercus robur L.). Wykazano, że na terenie parków publicznych Poznania stan zdrowotny omawianego gatunku jest dobry. Stwierdzono, że wpływ na stan zdrowotny tego gatunku w parkach Poznania mają: oddalenie od ścisłego centrum miasta, bliskość arterii komunikacyjnych oraz emisja gazów ze spalania paliw kopalnych przez sąsiadujące z parkami gospodarstwa domowe. Mimo że wyniki uzyskane w pracy potwierdzają dane literaturowe dotyczące wpływu zmiennych środowiskowych na stan zdrowotny dębu szypułkowego (Quercus robur L.), to wykazano, że niektóre zmienne środowiskowe mają większy wpływ na stan zdrowotny badanego gatunku w Poznaniu.

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Phytoplankton and environmental variables as a water quality indicator for the beaches at Matrouh, south-eastern Mediterranean Sea, Egypt: an assessment

Gharib S.M., El-Sherif Z.M., Abdel-Halim A.M., Radwan A.A.

Oceanologia

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2011

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No. 53 (3)

819-836

EN

This study was carried out to determine the water quality of the beaches at Matrouh, south-eastern Mediterranean Sea, Egypt, by studying environmental variables as well as phytoplankton abundance and community structure. Surface water samples were monitored from a series of beach sites over a period of five seasons during 2009-2010. A total of 203 phytoplankton species were identified from seven algal divisions. Seasonal differences in the quantitative and qualitative composition of the phytoplankton communities in the different sites were marked. Nutrient concentrations and phytoplankton abundances were found to be poorer than those of many other areas along Egyptian coast. The Shannon-Wiener Diversity Index classified Matrouh water as being between clean and moderately polluted, whereas the WQI demonstrated that it was between good and excellent. It can be concluded that the index based on WQI is currently more suitable than the phytoplankton species index for assessing the quality of the water of the Matrouh beaches.

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Peculiarities of macrozoobenthos in the offshore zone of a small artificial post-gravel pit reservoir

Żbikowski J., Kobak J.

Oceanological and Hydrobiological Studies

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2010

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Vol. 39, No.1

39-59

EN

The offshore macrozoobenthos and selected environmental parameters were studied in a small artificial reservoir, created through sand and gravel extraction. The results are rather surprising. Despite the shallow depth and good wind exposure of the reservoir, a thermal and oxygen stratification developed in the summer, causing hypoxic conditions near the bottom, even though the organic matter content in the sediments was <5%. Furthermore, despite the high fish abundance, chaoborids prevailed in zoobenthos, while Tanytarsus sp. and Chironomus sp. co-dominated among chironomids. This study attempts to explain the observed phenomena, though the presented hypotheses still need further confirmation.