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Effects of Light on the Microcystin Content of Microcystis Strain PCC 7806
A positive effect of PAR is shown up to the point where the maximum growth rate is reached, while at higher irradiances the microcystin production is inhibited. Expand
Concentrations of particulate and dissolved cylindrospermopsin in 21 Aphanizomenon-dominated temperate lakes.
CYN occurrence in the German lakes could not be ascribed to the three known CYN-producing species Cylindrospermopsis raciborskii, Anabaena bergii and Aphanizomenon flos-aquae, which were detected in some lakes in low abundances, and the highest correlation coefficients were observed between particulate CYN and the native AphanIZomenon gracile. Expand
Competitiveness of invasive and native cyanobacteria from temperate freshwaters under various light and temperature conditions
Any further temperature increase would promote the growth and development of Nostocales species in general, and that of the invasive species in particular, and would enable a more northward expansion of A. ovalisporum. Expand
First results on the performance of the HEGRA IACT array
Abstract First results concerning the performance characteristics of the HEGRA IACT array are given based on stereoscopic observations of the Crab Nebula with four telescopes. The system provides aExpand
Microcystins (hepatotoxic heptapeptides) in german fresh water bodies
The seasonal levels of these cyanobacteria were clearly reflected by microcystin concentrations in the water bodies, which varied by 4 orders of magnitude at bathing sites in 1997 during a mass development of Microcystis spp. Expand
Paralytic Shellfish Poisoning Toxin-Producing Cyanobacterium Aphanizomenon gracile in Northeast Germany
This study is the first confirming the role of A. gracile as a PSP toxin producer in German water bodies and isolating and characterizing 92 Anabaena, Aphanizomenon, and Anabaenopsis strains from five lakes in northeast Germany. Expand
Distribution of three alien cyanobacterial species (Nostocales) in northeast Germany: Cylindrospermopsis raciborskii, Anabaena bergii and Aphanizomenon aphanizomenoides
Investigating the spatial distribution and relative frequency of C. raciborskii close to its northernmost distribution limit and the habitat in which it is most likely to occur in this climatic zone concluded that alien thermophilic cyanobacterial species are much more widely distributed in temperate Germany than previously known. Expand
First report on cylindrospermopsin producing Aphanizomenon flos-aquae (Cyanobacteria) isolated from two German lakes.
Three single-filament isolates of Aphanizomenon flos-aquae from two German lakes were found to produce remarkable amounts of the cyanobacterial hepatotoxin cylindrospermopsin (CYN). CYN-synthesis ofExpand
Cyanobacteria and Cyanotoxins: The Influence of Nitrogen versus Phosphorus
Cyanobacteria should not be treated as a single group when considering the potential effects of changes in nutrient loading on phytoplankton community structure and neither should the N2-fixing Nostocales, as the two most abundant potentially toxin producing Nostocale in this study were found in lakes with high N relative to P enrichment. Expand
Climate change affects timing and size of populations of an invasive cyanobacterium in temperate regions
It is concluded that an earlier rise in water temperature associated with climate change has promoted the spread of C. raciborskii to the temperate zone, thereby shifting the pelagic populations to a phase with higher Imix, which advances growth and the population establishment. Expand