Many studies deal with water quality evaluation using remotely sensed data. In the field of remote sensing, there have been proposed several procedures how to observe selected parameters of water ...quality and conditions. The majority of works use methods and procedures based on satellite data but they usually do not deal with suitability and practicability of the satellite data. This paper provides summary of determinants and limitations of satellite data utilization for water quality evaluation. Cloud cover and its influence on size of visible water surfaces is the most deeply evaluated determinants. Temporal resolution, spatial resolution and some other technical factors are discussed as next determinants. The case study demonstrates evaluation of the determinants for Landsat 7 and Landsat 8 data (level 1) and for area of small ponds in part of Pardubice region in the Czech Republic. It clearly demonstrates several limitations of Landsat data for evaluation of selected parameters of water quality and changes of small water bodies.
The paper describes utilization of an unmanned aerial vehicle (UAV) for detection of changes of shorelines. UAV is used as a cheep and on-demand available possibility how to collect remotely sensed ...data. Its utilization is limited by legal regulations and weather conditions. Paper deals with utilization of UAV for monitoring small water area and particularly study of changes of shorelines. Study contains other methods of classification. After classification will be data processed for next calculations. Indices regarding shoreline changes are in the study also. In conclusion, study contains obtainment findings and encouragement for the future.
The paper describes utilization of an unmanned aerial vehicle (UAV) for detection of changes of shorelines. UAV is used as a cheep and on-demand available possibility how to collect remotely sensed ...data. Its utilization is limited by legal regulations and weather conditions. Paper deals with utilization of UAV for monitoring small water area and particularly study of changes of shorelines. Study contains other methods of classification. After classification will be data processed for next calculations. Indices regarding shoreline changes are in the study also. In conclusion, study contains obtainment findings and encouragement for the future.
Many studies deal with water quality evaluation using remotely sensed data. In the field of remote sensing, there have been proposed several procedures how to observe selected parameters of water ...quality and conditions. The majority of works use methods and procedures based on satellite data but they usually do not deal with suitability and practicability of the satellite data. This paper provides summary of determinants and limitations of satellite data utilization for water quality evaluation. Cloud cover and its influence on size of visible water surfaces is the most deeply evaluated determinants. Temporal resolution, spatial resolution and some other technical factors are discussed as next determinants. The case study demonstrates evaluation of the determinants for Landsat 7 and Landsat 8 data (level 1) and for area of small ponds in part of Pardubice region in the Czech Republic. It clearly demonstrates several limitations of Landsat data for evaluation of selected parameters of water quality and changes of small water bodies.
Monitoring changes of land cover near water bodies and water bodies themselves represents a part of environment protection and management. The management can be done at the global or local level. The ...local level requires more detailed data, which can be collected i.e. by means of aircraft or UAV. The paper describes a case study focused on the utilization of UAV-based RGB data to monitor land cover near the pond Baroch, which is located in the Czech Republic, near the city of Pardubice. The area is specific – it is a small pond accompanied by several smaller pools and connecting canals and surrounded by meadows (often watered), reeds, bushes and some trees Used data were collected by authors by in advance planned flights in August, September, October, November, and December 2021. Support Vector Machine, Maximum Likelihood, Random Trees, and Deep Learning are used as methods to process data and detect land cover changes. Manually interpreted data are used as reference data. Because of the nature of the data (only R, G, and B bands), classification into bare land, the water, vegetation, dry vegetation, and wet vegetation classes only was used. Very high heterogeneity of the observed area, availability of RGB bands only, and very high spatial resolution (1,9 cm per pixel) led to isolated cells.
Selected processing characteristics of new plum cultivars grown in the Czech Republic Bohacenko, I.,Vyzkumny Ustav Potravinarsky, Prague (Czech Republic); Pinkrova, J.,Vyzkumny Ustav Potravinarsky, Prague (Czech Republic); Komarkova, J.,Vyzkumny Ustav Potravinarsky, Prague (Czech Republic) ...
Horticultural science (Praha),
01/2010, Volume:
37, Issue:
2
Journal Article
Peer reviewed
Open access
Fermentable sugars (the total of glucose, fructose, and sucrose), sorbitol content, dry matter content, and titrable acidity were monitored in fruits of 16 new plum cultivars from the harvests in ...2004-2007. General linear model of two-factor grouping with testing of significance of simple contrasts with LSD method was used for statistical evaluation of plum cultivar chemical characteristics. Based on these results the tested cultivars were further divided into groups as regards their future processing into prunes, damson cheese or distillates. The traditional cultivar Italian Prune, grown in parallel, was used as the reference standard. Cvs. Gabrovska, Chrudimer, Elena, Hamanova, and President showed the best results and can be recommended for the production of distillates as well as prunes and damson cheese. Katinka, Anna Spath, and Veeblue are preferable for the production of distillates. Valjevka and Cacanska lepotica are suitable for processing into prunes and damson cheese. Substandard values of the studied characteristics were determined in Cacanska najbolja, Hanita and Voyageur. Cvs. Bluefree, Stanley, and Valor were evaluated as the worst ones.
The effect of temperature, light and nutrient composition on morphological traits was determined in seven nostocacean cyanobacteria
(Anabaena planctonica, A. sphaerica
var.
conoidea, A. spiroides, ...Aphanizomenon gracile, Nostoc
sp.,
Scytonema
sp., and
Tolypothrix
sp.). Their morphological variability was high but only some of the features showed changes reflecting varied growth conditions. The frequency of heterocyst occurrence decreased with increasing nitrogen concentration. Within the range studied, the effect of temperature on heterocyst frequency of
Tolypothrix
sp. and planktonic
Anabaena
strains could be fitted by a normal curve with a clear optimum while linear correlation was found in
Aphanizomenon gracile
. T-and S-type branching was observed in both
Scytonema
sp. and
Tolypothrix
sp. strains. T-type branching was found to be markedly dependent on nitrogen concentration. The abundance of necridic cells of
Tolypothrix
sp. increased linearly with temperature and light intensity. Regularity of trichome coiling of
A. spiroides
depended on culture medium, suggesting that nutrient composition may be the main controlling factor. In contrast, the effect of the experimental conditions on the dimensions of vegetative cells and heterocysts was weak. Their variability was markedly higher within each experimental treatment than between treatments.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Fish stock, zooplankton, chlorophyll a concentration, algal biomass (fresh mass), phytoplankton composition, species dominance and diversity (Shannon-Weaver Index and equitability) were evaluated to ...demonstrate their relevance in the trophic gradient at the levels of eutrophy and hypertrophy. Two patterns of food-web connectedness between phytoplankton and fish stock can be detected. One is direct (phytoplankton is mainly consumed directly by herbivorous or omnivorous fish) another one indirect (phytoplankton is consumed by zooplankton, which is regulated by the fish stock). Release of nutrients from fecal pellets and from the bottom due to the feeding activity of fish in shallow waters provide further feedbacks to the enhancement of phytoplankton growth. Changes in the predation pressure and bioturbation, as a consequence of shallowness, may be a source of intermediate disturbance which might promote phytoplankton diversity. Results from managed fish ponds (Komárková, 1983; Komárková et al., 1986), from reservoirs before and after biomanipulation (Komárková et al., 1995) and examples from a tropical lake Catemaco (Komárková & Tavera, 1996) confirm that the composition of phytoplankton is influenced, to varying degrees, by the nature and intensity of predation. Changes in fish stock can have both positive and negative effects on the transparency, concentration of nutrients and abundance of phytoplankton. Taxonomic composition and diversity of phytoplankton are affected differently, the effect being often the opposite from that predicted. Thus, in a water body with an unbalanced fish stock, using phytoplankton characteristics as the only criteria for identification of the trophic status can give incorrect information.
Full text
Available for:
EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Microscopic measurements of fresh biomass and 16S rRNA gene sequences from clone libraries and denaturing gradient gel electrophoresis (DGGE) were used to investigate cyanobacterial diversity in ...Polish water bodies in 2002. In addition, measurements of microcystin (MC) concentrations were made. Thirty water samples were taken from 11 water bodies; of these samples, 18 were obtained from the Sulejow Reservoir during regular monitoring from June to October. Intra- and extracellular MC concentrations in Sulejow samples were measured by high performance liquid chromatography (HPLC). The extracellular MC concentration was assessed using a protein phosphatase inhibition assay (PPIA) in additional lakes. Additionally, physicochemical parameters were measured (total nitrogen TN, total phosphorus TP, TN:TP ratio, chlorophyll a concentration, temperature). In Sulejow, high intracellular MC concentrations corresponded to large cyanobacterial biovolumes and to low TN:TP ratios. In the other lakes, extracellular MCs were not linked to any measured parameters. The combination of the microscopic and molecular data showed that Aphanizomenon and Microcystis were the dominant genera during the summer period in the Sulejow Reservoir. At the genetic level, there was a succession of 2 different operational taxonomic units (OTUs) belonging to the lineage Anabaena/Aphanizomenon. In the other water bodies, the most frequent populations were Aphanizomenon, Anabaena, Microcystis and Planktothrix. Small populations of Romeria, Snowella, Woronichinia, Limnothrix and Pseudanabaena were observed, and an enigmatic cluster affiliated with Prochlorothrix was genetically retrieved. Anabaena and Microcystis were presumed to be the main genera responsible for the MC production.
The impact of planktivorous fish on the plankton community structure and character of aquatic organic matter was studied by a meso-scale enclosure experiment in a stratified reservoir. Aims of the ...study were (i) to examine the response of the communities with and without herbivorous zooplankton to an increased input of phosphorus and (ii) to determine the composition and coagulation properties of the organic matter produced by these communities. The concentration and composition of organic matter were affected both in the enclosure with planktivorous fish (F), where high algal biomass developed, and in the enclosure without fish (Z), where algae were maintained at a low concentration by zooplankton grazing. Although differences between the enclosures in concentrations of total dissolved organic matter and its hydrophobic, hydrophilic and neutral/basic fractions were relatively small, coagulation properties of the organics differed substantially. Particulate and dissolved organic matter produced in enclosure F had a positive effect on the efficiency of alum coagulation in contrast to the less readily separable organics produced in enclosure Z. The results indicate that pelagic food web manipulations to maintainin low phytoplankton biomass by zooplankton grazing may not always have positive effects on the treatability of water by coagulation.
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