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Temporal and Seasonal Variations of Silicate Svratka River and Sediment Characterization, Czech Republic: Geochemical and Stable Isotopic Approach
Get PDFThis study investigated weathering and hydrobiogeochemical processes in a silicate dominated watershed (Svratka river) in the Czech Republic in comparison with nearby carbonate dominated catchments. Elemental and isotopic analysis of river waters, particulates and sediments provided a more holistic view of weathering contributions, anthropogenic contamination, biological activity and evasion or sinks of CO2 to the atmosphere. In water samples, we determined total alkalinity after Gran 1974, and cations and anions were determined with inductively coupled plasma-optical emission spectrometer and ion chromatograph. δ13CDIC in water samples was determined with isotope ratio mass spectrometer. pCO2 and saturation indexes of calcite and dolomite were calculated with PHREEQC speciation program. Evasion fuxes were calculated after Broecker, 1974. Isotopic composition of carbon and nitrogen in particulate matter and sediments were determined with isotope ratio mass spectrometer. Mineral composition of sediments was determined with XRD method and elements with XRF method. Further enrichment factors of elements were calculated. The Svratka river, which is the major tributary of the Dyje river, is dominated by Ca2+ > Na+ > Mg2+ > K+ and HCO3 MINUS SIGN (as total alkalinity). Partial pressure (pCO2) concentrations range from close to 0-572-fold of atmospheric pressure. Isotopic composition of carbon in dissolved inorganic carbon (δ13CDIC) value ranged fromMINUS SIGN 13.3 toMINUS SIGN 8.0%o refecting degradation of organic matter and exchange with the atmosphere. Bicarbonate weathering intensity for the Svratka river at its mouth is 11.8 mol/(lDOT OPERATOR km2 DOT OPERATOR s), more on par with silicate terrains and lower than nearby carbonate watersheds. Isotopic composition of carbon (δ13C) and isotopic composition of nitrogen (δ15N) values of river sediment refect soil and temperate plant (C3 plant) values, while higher δ15N values could be attributed to application of organic fertilizers in lower reaches. The river sediments, which came from weathering of crystalline rocks, are dominated by silt size, geochemically less mature quartz, feldspar and muscovite particles. All the stream sediments examined revealed slightly increased amounts of Zn, Cu and Pb. However, using Al as the normalization element to calculate enrichment factors, Zn, Cu and Pb are only elevated downstream, related to industrial contamination. This study is important for local and global level since it deals with contribution of weathering rates and contribution of CO2 to the atmosphere in silicate watershed.O
Ergosterol and polyphenol contents as rapid indicators of orchardgrass silage safety
Get PDFThe ergosterol (ERG) has been proposed as a potential indicator of fungal contamination, along with polyphenol content analysis to predict silage safety. Despite efforts in controlling fungal growth in silage, mycotoxin co-contamination represents a possible risk for animal and human health. Modern analytical techniques determine a multitude of fungal metabolites contaminating feed. Nonetheless, these methods require sometimes arduous sample pre-treatment, long separation times, and expensive standard compounds to identified contaminants. Thus, the goal of this study was to suggest a rapid analysis of ERG and polyphenol contents to assess silage hygienic quality in ten orchardgrass varieties ensiled without and with biological and chemical additives. The determination of ERG on samples was performed by high-performance liquid chromatography using UV detection and UV/Vis spectrophotometry to determine the polyphenol content. Statistically significant differences (P < 0.05) between varieties, years and silage additives were found. Bepro was the unique variety that did not present ERG in the first cut in 2012. ERG content increased in the first cut in 2013 using biological additives as well as ERG and polyphenol contents in the first cut in 2013 using chemical additives compared with untreated silage. In addition, biological and chemical additives used in this study did not satisfactorily reduce the content of ERG and polyphenols in silage grass. Consequently, our results provide fast information about the progressive fungal contamination of grass silage. To our knowledge, it is the first time that the presence of ERG and polyphenols is determined in ten different orchardgrass varieties treated without and with additives. In general, ERG and polyphenol contents showed to be good indicators of orchardgrass silage safety.O
Has Policy Rate Been an Effective Tool in Taming Inflation?
Get PDFThis paper explores the effectiveness of monetary policy rate as a tool to tame Inflation in sub-Saharans Africa using the systems GMM and other econometric approaches. Financial data (unconsolidated) from Orbis for the period 2011-2018 was used for the purpose of this study. We find that expected Inflation, GDP growth rate, unemployment, Exchange rate, broad money supply, and policy rate significantly influence the inflation rate in SSA. To the margin that the monetary policy rate has the most substantial impact on Inflation in the region and that re-evaluating monetary policy design could help control Inflation. The paper concludes that the credibility and accountability of the monetary policy authorities should be improved by setting targets appropriate to their institutional capacity and meeting them.O
Rheological and fermentation properties of doughs and quality of breads from colored wheat varieties
Get PDFThe objective of this study was to examine the rheological and fermentation behavior of doughs prepared from five different colored wheat varieties (black AF Zora, yellow KM 111-18, purple AF Jumiko, blue AF Oxana and red Vanessa - chosen as a standard), which contain polyphenolics in the outer layers of grains. Three wholemeal flour fractions (fine, semi-coarse and coarse) were used for each variety. The flour fractions differed in the particle size of the bran, the ash content and thus the phenolic compound content. The baking trials, texture and sensory analyses of breads were performed, to assess their overall acceptability. The coarser granulation of flour fractions, average hardness (8.5<12.6<20.2 N) and chewiness (584<796<1053 N) of breads increased, while other parameters: springiness (90>87>77%), cohesiveness (78>75>70%) and resilience (35>32>27%) decreased. Moreover, the increase in off-flavors was detected with higher bran content. Regarding the flour granulation, the fine fraction seemed to be the most suitable due to its high gas-retention capacity. The best products in terms of both dough and bread quality reached blue AF Oxana and yellow KM 111-18. Utilization of colored wheat in bakery industry may present a good strategy of providing value-added products to the consumers.O
The efficiency of different types of extenders for semen cooling in stallions
Get PDFObjective: This study was conducted to examine influence of skimmed milk-based extender (SM), INRA 96 extender and BotuSemen Gold extender on parameters of stallions' ejaculate during storage. Methods: In this study, 14 stallions between 4 and 20 years of age were monitored. Total and progressive motility, viability and morphology of sperm were evaluated at time intervals of 24, 48, and 72 hours after collection. Results: The total motility, progressive motility, and values of sperm with normal morphology were significantly higher in the INRA 96 and BotuSemen Gold extenders than in the SM (p<0.01). The sperm viability differed significantly in all extenders (p<0.01). The highest value of sperm viability was in INRA 96 (64.69%+-0.67%) and lowest in SM (59.70%+-0.81%). The highest differences occurred at 72 hours of storage. Values of total motility, progressive motility and sperm viability decreased over time (p<0.01). In case of sperm morphology there was no statistically significant decrease between 48- and 72-hour time intervals. Conclusion: It can be concluded that the extenders with a chemically defined composition have shown better indicators of insemination capabilities in ejaculates than the SM. The BotuSemen Gold extender is a suitable alternative to the INRA 96, when used within 48 hours; after 72 hours of storage, however, the INRA 96 showed a higher share of viable spermatozoa.Published Versio
Foliar Application of ZnO-NPs Influences Chlorophyll Fluorescence and Antioxidants Pool in Capsicum annum L. under Salinity
Get PDFZinc oxide nanoparticles (ZnO-NPs) have been proven to helpfully improve plant tolerance to several abiotic stresses. However, no information has been reported concerning the role of ZnO-NPs on pepper plants under salinity stress. Hence, this research aimed to evaluate the growth and physiological responses of pepper (Capsicum annum L.) plants to ZnO-NP foliar application under salinity. Plants were subjected to 0 (control), 25 (S1), 50 (S2), and 75 mM (S3) NaCl salinity with a foliar spray of 0, 1000, and 2000 ppm ZnO-NPs. Significant reductions were recorded in the chlorophyll index (SPAD) and chlorophyll fluorescence parameters, and in the activity and/or ratios of reduced ascorbate (AsA), reduced ascorbate/dehydroascorbic acid (AsA/DHA), reduced glutathione (GSH), reduced glutathione/oxidized glutathione (GSH/GSSG), and K+ content. There was a significant increase in proline content, electrolyte leakage (EL), H2O2 content, guaiacol peroxidase (GPX), ascorbate peroxidase (APX), superoxide dismutase (SOD), glutathione reductase (GR), dehydroascorbic acid (DHA), and oxidized glutathione (GSSG) activities, and in Na+ content and Na+/K+ ratio. Foliar treatments improved the salinity tolerance of the pepper plants by fortifying the antioxidant defense system, leaf fluorescence parameters, K+, and proline content, and in contrast, by decreasing the EL, Na+, and H2O2 levels. ZnO-NP foliar treatment efficiently improved the pepper plants' physiological responses under salinity. Considering the overall results, 1000 ppm of ZnO-NPs would be advisable for the amelioration of salinity depression and to promote growth potential. However, at higher levels, the nanoparticle showed toxicity symptoms that limited its reliable applications.O
Analysis of significant factors influencing the amount of collected forest berries in the Czech Republic
Get PDFBilberries (Vaccinium myrtillus L.), raspberries (Rubus idaeus L.), blackberries (Rubus fruticosus L.) and cowberries (Vaccinium vitis-idaea L.) are the most important forest berries collected in the Czech Republic (CZ). The average annual value of these collected berry species is estimated to be worth more than EUR 86 million at 2018 prices. The data concerning the collection and use of forest fruits have been systematically collected in a highly detailed structure since 2008, which enables the application of the advanced statistical methods used in this paper. The results of the analyses inter alia demonstrate that collecting forest berries is not only an important recreational activity, but it has an important economic effect. Therefore, this article also deals with the collection of forest fruits, especially bilberries, as a potentially important non-wood forest product (NWFP) for sustainable forest management and also analyses the external factors influencing the total annual amount of collected forest berries. A deeper knowledge of the customer and his or her behaviour- customer insight-are prerequisites for the proactive management of forest ecosystems. The first step to "berry picker insight" is to learn more about the demand, its structure and factors which influence this demand. Thus, one of the research questions concentrates on the analysis of the sociodemographic characteristics of the berry picker that are relevant for explaining the amount of collected forest berries in the Czech Republic. Knowledge of these factors can contribute to a more effective application of marketing methods for shaping and influencing the demand so that, in terms of time and place, it is more in line with the supply, which is limited by the natural conditions, growing season and production potential of forest ecosystems.O
Wild birds and mammals in Nicaragua and its regional development
Get PDFDivocí ptáci a savci byli v Nikaragui pozorováni v nížinách (okolí měst Rivas, Tipitapa, León a El Limón), v okolí vulkánů (Maderas, Concepción, Mombacho, Masaya, Cerro Negro a bahnité sopky Los Hervideros de San Jacinto), v centrálním pohoří Kordiller (Kaňon Somoto, okolí měst Condega, Estelí, Jinotega, Selva Negra a Matagalpa, jezero Apanas) a v jiných lokalitách. Podařilo se druhově určit a vyfotografovat 63 druhů ptáků patřících do 17 řádů (dlouhokřídlí, šplhavci, terejovití, měkkozobí, dravci, svišťouni, kondoři, pěvci, kukačky, veslonozí, lelkové, krátkokřídlí, papoušci, srostloprstí, trogoni, sovy a hrabaví). Celkem 21 druhů savců patřilo do 7 řádů (hlodavci, letouni, primáti, sudokopytníci, vačice, šelmy a chudozubí). Jejich české, anglické, španělské a latinské názvy byly obohaceny i místními názvy, pod kterými je většinou znají místní obyvatelé. Četné druhy jsou významnou součástí ekosystémů, některé druhy jsou součástí místní kultury včetně pověr a některá zvířata a ptáci jsou loveni a konzumováni pro zpestření jídelníčku. Mnohé druhy jsou ohrožené a jsou přísně chráněné. Cílem této monografie je snaha o přiblížení těchto zvířat z pohledu regionálního rozvoje Nikaragui se všemi pozitivními i negativními faktory, které bývají turistům a jiným návštěvníkům této středoamerické země skryty.Wild birds and mammals of Nicaragua were observed in the lowlands (around cities Rivas, Tipitapa, León and El Limón), around volcanoes (Maderas, Concepción, Mombacho, Masaya, Cerro Negro and the muddy volcanoes of Los Hervideros de San Jacinto), in the central oun tains Cordillera (Somoto Canyon, near the towns of Condega, Estelí, Jinotega, Selva Negra and Matagalpa, lake Apanas) and other locations. A total of 63 species of birds from 17 orders Long-winged, Woodpeckers, Cormorants, Pigeons' and doves', Birds of Prey Order, Swift, Condors Order, Songbirds, Cuckoos, Pelican, Nightjar, Gruiform, Parrots, Raven-like, Trogon, Owls and Galliformes) were identified and photographed. A total of 21 mammalian species belong ing to 7 orders (Rodents, Chiropteran, Primates, Even-toed Ungulates, Opossums, Carnivorous and Xenarthral) were iden tified. Their Czech, English, Spanish and Latin names have been complimented with! local names, under which they are commonly known the locally. Most species of birds and mammals play an important role in the varied ecosystems in Nicaragua. Many species are also imbedded in the culture of the Nicaraguan people in ways such as being part of the local diet as well being involved in superstitions and customs. Many species are endangered and are strictly protected. The aim of this mon ograph is to bring to light the place these animals have in the regional development of Nicaragua, including the positive and negative factors that are often hidden from tourists and other visitors to this Central American country.Published Versio
Comparison of the Biomass and Dendrometric Parameters of Norway Spruce with Its Different Representations in Young Stands at Lower Altitudes in the Czech Republic
Get PDFIn forestry, it is still common to plant the seedlings of and cultivate Norway spruce (Picea abies L. Karst) at lower altitudes; however, the climatic change that has been occurring increases evaporative demands in these areas. As a result, the spruce evidently suffers from drought, withers and loses its power to grow, thus, influencing stem thickness and tree-height growth, as well as biomass production. Therefore, the growth and biomass production of young (5-, 15- and 25-year-old) Norway spruce stands at these altitudes (i.e., from 200 to 500 m a.s.l.) was surveyed, as a case study, across the Training Forest Enterprise "Masaryk Forest" Křtiny. There, 48 stands with a varied representation of spruce (i.e., up to 30%, 31%-60%, 61%-90% and over 91%) were analyzed. In each stand, 12 trees were sampled across all social status classes (i.e., sub-dominant, co-dominant and dominant) in detail. Basic dendrometric parameters (such as the total tree height, height of the crown base and stem diameter at breast height) and the amount of the above-ground tree organ biomass (i.e., stem, branches and needles) were investigated. Based on the trends found in the biomass production here and climate change predictions, we recommend that Norway spruce be cultivated only in zones from an altitude of ca 400 m a.s.l., with an annual precipitation of 700 mm and an average annual temperature of 7 oC, and its percentage representation in the stand be no more than 30%.O
Suitability of Using Mechanization Means for the Maintenance of Grass Stands by the Method of Mulching
Get PDFThis study aims to provide comprehensive and practical information on particular mechanization means used in the maintenance of permanent grass stands, namely grass cutting technologies without the collection of cut grass biomass - mulching. A sample consisting of six machines classified into three categories (uniaxial tool carriers, single-axle small tractors, cutting machines with a zero turning radius) was tested in practice and functional and operational aspects of the machines were studied on different localities of permanent grass stands. Data measured in the individual machines were used to calculate consumption [l/ha], consumption [l/mth], consumption [l/l of cut biomass] or performance [ha/hour]. The measurements took place on two sites: a site with the permanent grass stand unkempt for a long time and a site regularly maintained by mulching. The study was conducted in the cadastral area of Ostrava City situated in the NE part of the Czech Republic. Results of the study show that the total fuel consumption [l/ha] in the individual mowing machines always at all times higher on plots that were unkempt for a long time. The overall comparison of fuel consumption [l/mth] of the individual types of cutting machines between the localities showed that nearly all tested cutting machines had a higher consumption on sites with permanent grass stands unkempt for a long time. The performance [ha/h] of all cutting machines was higher on the sites that were regularly maintained by mulching in the past.O