scholarly journals Pediastrum species (Hydrodictyaceae, Sphaeropleales) in phytoplankton of Sumin Lake (Łęczna-Włodawa Lakeland)

2011 ◽  
Vol 73 (1) ◽  
pp. 39-46 ◽  
Author(s):  
Agnieszka Pasztaleniec ◽  
Małgorzata Poniewozik
Keyword(s):  
Rare Species ◽  
Common Species ◽  
Water Bodies ◽  
Physico Chemical ◽  
Chemical Conditions ◽  
Interesting Species ◽  
Pediastrum Boryanum

During studies of phytoplankton in Sumin Lake (Łęczna-Włodawa Lakeland), conducted from May till September 2001 and 2002, 15 taxa of the genus <em>Pediastrum </em>(Hydrodictyaceae, Sphaeropleales) were found. Among them there were common species as <em>Pediastrum boryanum</em>, <em>P. duplex</em>, <em>P. tetras </em>and <em>P. simplex</em>, but also rare species as <em>P. integrum </em>or <em>P. kawraiskyi</em>. An especially interesting species was <em>P. orientale</em>, the taxon that until now has not been noted in phytoplankton of Polish water bodies. The paper gives descriptions of the genus <em>Pediastrum </em>coenobia and physico-chemical conditions of the habitat. The original documentation of <em>Pediastrum </em>taxa is added.

scholarly journals Revision of the characeae (Charales, Charophyceae) species and their distribution in Lithuania

Botanica ◽  
2021 ◽  
pp. 95-124
Author(s):  
Zofija Sinkevičienė ◽  
Zigmantas Gudžinskas
Keyword(s):  
19Th Century ◽  
Rare Species ◽  
Common Species ◽  
Water Bodies ◽  
Herbarium Specimens ◽  
Grid Cells ◽  
Nitellopsis Obtusa ◽  
Chara Globularis ◽  
The 19Th Century ◽  
Occurrence Of Species

The current inventory was mainly based on revising herbarium specimens collected since the 19th century and confirmed twenty-one Characeae species in Lithuania. They are representatives of five genera: Chara (12 species), Nitella (5), Tolypella (2), Lychnothamnus and Nitellopsis (by one species each). Thirteen species mentioned in references or labels of herbarium specimens were not confirmed. The occurrence of the Characeae species was recorded in 251 map grid cells (42% of the total number 593). Herbarium specimens were collected from 693 water bodies, mainly lakes. Chara globularis was the most common species, recorded in 150 map grid cells and more than 250 water bodies. Ten species (C. aspera, C. contraria, C. filiformis, C. subspinosa, C. tomentosa, C. virgata, C. vulgaris, Nitella mucronata, N. flexilis, Nitellopsis obtusa) were recorded in the interval from 100 to 50 grid cells and also belong to the group of common species. Chara papillosa and C. strigosa were recorded less than in 50 grid cells and should be considered quite common. Eight species (C. baltica, C. canescens, Lychnothamnus barbatus, Nitella confervacea, N. gracilis, N. syncarpa, Tolypella nidifica, T. prolifera) were recorded in ten or fewer grid cells and belong to the group of rare or very rare species. The occurrence of species that have not been confirmed by the herbarium specimens was discussed.

scholarly journals Ecohydromorphology of river environments of the das Velhas River upstream of Rio de Pedras hydroelectric reservoir, MG, Brazil

2016 ◽  
Vol 4 (1) ◽  
pp. 41
Author(s):  
Helena Lúcia Menezes Ferreira ◽  
Paulo de Tarso Amorim Castro ◽  
Márcia Couto Melo ◽  
Pedro Fialho Cordeiro ◽  
Aylton Carlos Soares ◽  
...  
Keyword(s):  
River Basin ◽  
Large Scale ◽  
Ecological Integrity ◽  
River System ◽  
Minas Gerais ◽  
Water Bodies ◽  
Hydroelectric Reservoir ◽  
Physico Chemical ◽  
Chemical Conditions

<p>This paper presents the applicability of ecohydromorphology assessment in differentiating ecophysical structure of river habitats of Rio das Velhas river basin upward of Rio de Pedras reservoir, Minas Gerais,Brazil. It also presents the identification of the factors conditioning the ecophysical structure of river habitats. This review associated with biological and physico-chemical conditions of the waters aims to assess the ecological integrity of the river system and also validate the characterization of water bodies identified on a large scale in the Rio das Velhas basin.</p>

Viability of nematode eggs in high rate algal ponds: the effect of physico-chemical conditions

2000 ◽  
Vol 42 (10-11) ◽  
pp. 371-374 ◽  
Author(s):  
S. Araki ◽  
J. M. González ◽  
E. de Luis ◽  
E. Bécares
Keyword(s):  
Hydraulic Retention Time ◽  
Pilot Scale ◽  
High Rate ◽  
Sterile Water ◽  
Egg Viability ◽  
High Rate Algal Ponds ◽  
Helminth Eggs ◽  
Physico Chemical ◽  
Nematode Eggs ◽  
Chemical Conditions

The viability of Parascaris equorum eggs was studied in two experimental pilot-scale high-rate algal ponds (HRAPs) working in parallel with 4 and 10 days hydraulic retention time respectively. Semi-permeable bags of cellulose (15000 daltons pore size) were used to study the effect of physico-chemical conditions on the survival of these helminth eggs. Three thousand eggs were used in each bag. Replicates of these bags were submerged for 4 and 10 days in the HRAPs and egg viability was compared with that in control bags submerged in sterile water. After 4 days exposure, 60% reduction in viability was achieved, reaching 90% after 10 days, much higher than the 16% and 25% found in the control bags for 4 and 10 days respectively. Ionic conditions of the HRAP may have been responsible for up to 50–60% of the egg mortality, suggesting that mortality due to the ionic environment could be more important than physical retention and other potential removal factors.

scholarly journals Assessment of the Impact of Small Hydropower Plants on the Ecological Status Indicators of Water Bodies: A Case Study in Lithuania

Water ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 433
Author(s):  
Laima Česonienė ◽  
Midona Dapkienė ◽  
Petras Punys
Keyword(s):  
Water Quality ◽  
Benthic Macroinvertebrates ◽  
Suspended Solids ◽  
Ecological Status ◽  
Fish Abundance ◽  
Water Bodies ◽  
Small Hydropower ◽  
Hydropower Plants ◽  
Physico Chemical ◽  
The Impact

Hydropower plants produce renewable and sustainable energy but affect the river’s physico-chemical characteristics and change the abundance and composition of the aquatic organisms. The impact of large HPPs on the ecological conditions of surface water bodies have been extensively studied, but less attention has been paid to environmental impact studies of small hydropower plants (SHPs). The impact of hydropeaking on both the river flow regime and ecosystems has been well-studied for peaking mode plants, mainly medium to large-sized ones. However, for small hydroelectric power plants, and especially for those in lowland rivers, the available information on water quality, benthic macroinvertebrates communities and fish abundance, and biomass is not sufficient. Ten small hydropower plants were selected, and the ecological status of water bodies was assessed in different parts of Lithuania. The studies were performed at the riverbed upstream from the SHPs, where the hydrological regime has not changed, and downstream from the SHPs. It was found that the small hydropower plants do not affect the physico-chemical values of the water quality indicators. This study demonstrated that the total number of benthic macroinvertebrates taxa (TS) is influenced by the concentration of nitrogen and suspended solids, the water flow, the river area, and the current speed; the number of EPT (Ephemeroptera (mayflies), Plecoptera (stoneflies), and Trichoptera (caddisflies)) taxa is influenced by the concentration of nitrogen and suspended solids. The studied indicators do not have a significant impact on biomass. The SHPs affect the fish abundance and biomass. The Lithuanian fish index (LFI) is influenced by the average depth and area of the river. Some SHPs operating in lowland areas may yield somewhat significant hydrograph ramping but more detailed investigation is needed to support the significance of this impact on the biological indices.

scholarly journals Compartmentalization of bacterial and fungal microbiomes in the gut of adult honeybees

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Matteo Callegari ◽  
Elena Crotti ◽  
Marco Fusi ◽  
Ramona Marasco ◽  
Elena Gonella ◽  
...  
Keyword(s):  
Gut Microbiome ◽  
Bacterial Phylotypes ◽  
Specific Variable ◽  
The Core ◽  
Physico Chemical ◽  
Metabolic Conditions ◽  
Chemical Conditions ◽  
And Behavior

AbstractThe core gut microbiome of adult honeybee comprises a set of recurring bacterial phylotypes, accompanied by lineage-specific, variable, and less abundant environmental bacterial phylotypes. Several mutual interactions and functional services to the host, including the support provided for growth, hormonal signaling, and behavior, are attributed to the core and lineage-specific taxa. By contrast, the diversity and distribution of the minor environmental phylotypes and fungal members in the gut remain overlooked. In the present study, we hypothesized that the microbial components of forager honeybees (i.e., core bacteria, minor environmental phylotypes, and fungal members) are compartmentalized along the gut portions. The diversity and distribution of such three microbial components were investigated in the context of the physico-chemical conditions of different gut compartments. We observed that changes in the distribution and abundance of microbial components in the gut are consistently compartment-specific for all the three microbial components, indicating that the ecological and physiological interactions among the host and microbiome vary with changing physico-chemical and metabolic conditions of the gut.

scholarly journals Dissolved organic nutrients at the interface of fresh and marine waters: flow regime changes, biogeochemical cascades and picocyanobacterial blooms—the example of Florida Bay, USA

2021 ◽  
Author(s):  
Patricia M. Glibert ◽  
Cynthia A. Heil ◽  
Christopher J. Madden ◽  
Stephen P. Kelly
Keyword(s):  
Water Quality ◽  
Anthropogenic Activities ◽  
Florida Bay ◽  
Climate Conditions ◽  
Regime Changes ◽  
Physico Chemical ◽  
Organic Nutrients ◽  
High Concentrations ◽  
Chemical Conditions ◽  
Favorable Conditions

AbstractThe availability of dissolved inorganic and organic nutrients and their transformations along the fresh to marine continuum are being modified by various natural and anthropogenic activities and climate-related changes. Subtropical central and eastern Florida Bay, located at the southern end of the Florida peninsula, is classically considered to have inorganic nutrient conditions that are in higher-than-Redfield ratio proportions, and high levels of organic and chemically-reduced forms of nitrogen. However, salinity, pH and nutrients, both organic and inorganic, change with changes in freshwater flows to the bay. Here, using a time series of water quality and physico-chemical conditions from 2009 to 2019, the impacts of distinct changes in managed flow, drought, El Niño-related increases in precipitation, and intensive storms and hurricanes are explored with respect to changes in water quality and resulting ecosystem effects, with a focus on understanding why picocyanobacterial blooms formed when they did. Drought produced hyper-salinity conditions that were associated with a seagrass die-off. Years later, increases in precipitation resulting from intensive storms and a hurricane were associated with high loads of organic nutrients, and declines in pH, likely due to high organic acid input and decaying organic matter, collectively leading to physiologically favorable conditions for growth of the picocyanobacterium, Synechococcus spp. These conditions, including very high concentrations of NH4+, were likely inhibiting for seagrass recovery and for growth of competing phytoplankton or their grazers. Given projected future climate conditions, and anticipated cycles of drought and intensive storms, the likelihood of future seagrass die-offs and picocyanobacterial blooms is high.

scholarly journals Croonian lecture.—Observations on isolated nerve. Electrical changes a measure of physico-chemical change

1896 ◽  
Vol 59 (353-358) ◽  
pp. 308-312
Keyword(s):  
Chemical Change ◽  
Physico Chemical ◽  
Chemical Conditions

The present investigation arises from experiments undertaken to determine autographically the varying relations between the magnitude of electrical change and the magnitude of stimulation in nerve under various chemical conditions.

SECONDARY CHANGES IN CARBONATE ROCKS OF OIL AND GAS COMPLEXES

2020 ◽  
pp. 18-23
Author(s):  
M.A. Tugarova
Keyword(s):  
Carbonate Rocks ◽  
Oil And Gas ◽  
Carbonate Reservoirs ◽  
Fundamental Importance ◽  
Schematic Diagram ◽  
Reservoir Properties ◽  
Physico Chemical ◽  
Chemical Conditions ◽  
First Time

The article considers the secondary transformations of carbonate rocks of oil and gas complexes, which are of fundamental importance in the formation of reservoir properties. For the first time, a schematic diagram, illustrating the regularities of secondary processes in carbonate reservoirs and their relationship with the physico-chemical conditions of the stratosphere is proposed.

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