National Repository of Grey Literature 11 records found  1 - 10next  jump to record: Search took 0.01 seconds. 
Management of permanent grasslands in relation to agri-environmental measures: Questions and answers
Gaisler, Jan ; Pavlů, Vilém ; Mládek, Jan ; Hejcman, Michal ; Pavlů, Lenka
This methodology simplified results from research project “Functional plant traits and their diversity as indicators of various permanent grassland management” for nature conservation authority. It is based on long term grassland experiments. There are important data for preparing of some agro-environmental provision in the practical part. This work summarises the results of long-term experiments with the different management treatments. It is intended especially for employers of administration of nature conservation, and also it can be used for students and pedagogues of secondary schools and universities concerning nature conservation.
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Methodical practice of taking samples fertilizers, plants and soil for determination of risk elements in agro-ecosystems and other parameters of soil fertility: applied methodology with certification
Kunzová, Eva ; Menšík, Ladislav ; Hejcman, Michal ; Dostál, Jiří
The methodology is describing latest findings on methods of sampling of barnyard manure, organic and organomineral fertilizers, samplings of vegetable material and soil for determination of risk elements content. As a part of the methodology there is description of laboratory methods for determination of dry matter content, pH, content of essential nutrients and risk elements in samples (of farmyard manure, organic and organomineral fertilizers, vegetable material and soil). Methodology is describing methods of characterization of quality of soil organic matter (SOM) and most important limit valuables of risk elements in fertilisers, substrates and soils. The application of methodology will be in the corporation farming on arable soil, grassland, classical and also ecological agriculture. It will be used also by accredited laboratories, agricultural consultant and in advisory framework of Ministry of Agriculture of Czech Republic etc. Methodology can be used by civil servants, students and teachers in secondary schools and agricultural universities etc.
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Effect of long-term fertilizer application on content of risk elements in grassland soil
Jungová, Michaela ; Hejcman, Michal (advisor) ; Pavlů, Vilém (referee)
The long-term Steinach Grassland Experiment is probably one of the oldest still-running fertilised grass experiments in continental Europe. The experiment was established on an alluvial meadow Alopecurus pratensis in southeastern Germany in 1933. The meadow was divided into 75 plots and fertilised with both mineral and organic fertilisers of differing compositions and amounts. The aim of this study was to provide more detailed information about the effects of long-term fertilisation by natrium (N), phosphorus (P) and potassium (K) on the contents of risk elements in soil. The effects of long-term fertilisation were investigated in the extracts of a) plant-available elements (extraction of CaCl2), b) easily mobilised elements (extraction of EDTA), c) potentially mobilisable elements (extraction of HNO3), the total concentration of elements (extraction of Aqua regia). Concentrations of risk elements As, Cr, Cu, Fe, Mn, Ni and Zn in the soil profile has increased substantially due to the phosphorus fertilisation; however, the limits for total trace elements concentration as set by the Czech legislation have been exceeded only twice, namely in the case of As and Cd. The total concentration of As (AsT) has been exceeded only once, on the plot fertilised only by nitrogen. The assumption is that that the increased level of AsT fraction in soil was probably caused in the past by fertilising with Thomas slag which is known to contain elevated concentrations of As. However, fertilising with the phosphorus-containing fertilisers has had the opposite effect on concentrations of Mn, Ni and Zn that are easily available to plants; concentrations of these elements in the soil extraction were substantially higher. In spite of the overall concentrations of Cd being lower than the Czech legislative standards, the results on several plots fertilised by mineral and organic fertilisers containing N, P and K showed higher concentrations of Cd and in one case reached the limit value. Plots fertilised by mineral fertilisers N160P44K174 (NH4)2SO4 recorded higher Cr concentrations. In overview, it could be stated that under various types of fertilising no substantial effects of long-term fertiliser applications on a higher content of risk elements in soil has been detected. Only two plots have exceeded the limits set by Notice 13/1994 Sb., in one case it was a total concentration of As and in another one that of Cd.
Effect of fertilizers application on grassland ecosystems: what can tell us long-term experiments?
Hejcman, Michal ; Suchara, Ivan (advisor) ; Hájek, Michal (referee) ; Poschlod, Peter (referee)
GENERAL CONCLUSIONS Benefit of all present papers for current stage of knowledge is directly obvious from their text. So, I will summarize the main benefit of each paper very briefly here. Chapter 2 - From the comparison of long-term vs short-term nutritional effects, it was concluded that long-term fertilizer experiments are irreplaceable as many existing models and predictions can be validated only by means of long-term manipulation of plant communities and their continuous observation and documentation. Chapter 3 - Long-term fertilizer application can create grasslands with no overlap of plant species composition in the scale of several meters. Species indicative of low productivity grasslands (short grasses, orchids, and sedges) can survive longterm nitrogen application if phosphorus is limiting nutrient for growth of highly productive grassland species. Chapter 4 - Long-term addition of limiting nutrient can affect grassland ecosystem in three ways: 1) by change in plant species composition without significant increase in total biomass production, 2) by no change in species composition but with significant increase in total biomass production, and 3) by substantial change in plant species composition accompanied by significant increase in total biomass production. Chapter 5 - Long-term fertilizer...
Ecology of Calamagrostis epigejos (L.) Roth
Vachová, Pavla ; Hejcman, Michal (advisor)
Ecology of expansion species is still a hot topic. The antropogenic landscape gradually occurred since the Neolithic . The result has been a change in the structure of plant communities and the successful expansion of species such as Calamagrostis epigejos. C. epigejos is expansive, perennial, long-stemmed, rhizomatous grass. Its important characteristic are very large ecological amplitude, high biomass production and a ability adjust habitat conditions. Experiments and studies that are included in dissertation, have the following basic objectives: (1) Investigate the expansion of C. epigejos in plant community. (2) Investigate the theoretical degree of stability of this phytocenosis. (3) Determine the response of C. epigejos to nutrients availability. (4) Test of possibility eliminating of C. epigejos. (5) Suggest a practical use of C. epigeos. Primarily, we monitored the reaction of interest species to management (aplication of N, P, K nutrients, mowing in various combinations). We were interested in its behavior in the plant community. It founded field and pot experiment. Results of field experiment were also used to calculate the theoretical measure of the stability of individual variants. Further research has been directed at eliminating C. epigejos using wireworms (Elateridae larvae species). The study which uses C epigejos for monitoring of deposition of heavy metals, has shown that aspects of the global expansion of the grass are not always negative.
Risk elements contamination in Kutná Hora region and possibilities of its usage in paleoenvironmental research
Horák, Jan ; Hejcman, Michal (advisor) ; Jaromír, Jaromír (referee)
The dissertation focuses on topic of using risk elements contamination as a stratigraphic marker in palaeoenvironmental research. The contamination is not studied only as itself, but is viewed as a way to analyse and interpret the sedimentary record of historical events. The contamination carries the information about its original place, its original activity, about development of the landscape. The Kutná Hora region (central Bohemia; 49°57'0.170"N, 15°15'59.877"E) is a region of important historic mining and smelting activity. The mining started in 13th century and lasted until half of 16th century. Then only sporadic attempts of renewal were made. Spatially limited mining was renewed in second half of the 20th century. Therefore, it is highly probable to find here the contaminants in the role of stratigraphic markers. In the research were used mainly As, Be, Cd, Co, Cr, Cu, Hg, Pb, V and Zn as these are the most analysed in contamination studies performed in the region. The aims of the dissertation were to answer these questions: To characterize the contamination - Are some risk elements typical for the contamination originating from the mining and smelting? - If so, is their environmental (spatial, sedimentary) manifestation diversified? - Is possible diversity spatially related to particular landscape features or areas? - Is possible diversity connected to particular activities? To use the answers in analysis of particular sites - Is it possible to use the risk elements contamination as stratigraphic marker in fluvial sediments? - How is the interpretation of particular site influenced by the whole context of regional contamination? The core of the research is the metaanalysis of contamination data coming from region (the data obtained by our research and also from other studies). The results have brought not only basic characteristics of contamination, mainly concentrations. The crucial result was the structure of studied elemental complex. Only As, Cd, Cu, Pb and Zn are connected to contamination originating in mining and smelting. Other elements - their concentrations and spatial distributions - are uninfluenced by mining and smelting activities. More, the information about connection of As and Cd to mining and Cu, Pb and Zn to smelting was revealed. Both groups recorded with different spatial distributions. Also comparison of results by different approaches has shown that some statistical processing (clr-transformation) of such dataset was much better for interpretation than analyses of only concentrations values. We studied also the area of confluence of two rivers - Klejnárka (main river draining contaminated region), which is tributary to Labe (Elbe) river. The contamination is still recognizable here, but the diversity between contamination elements is not. The confluence of rivers strongly dilutes the contaminated material. The concentrations decrease. Also here clr-transformation of data enabled to analyse structures of contaminants spatial distribution unrecognizable by concentrations values. We performed also two vertical profiles analyses. It was shown, that it is highly risky to interpret data of such origin without the complex information about regional contamination context. It was revealed by contextual interpretation of data from one of the profiles, that there is a mixing of geochemical data coming from different statistical populations. The contamination works there as only one of the factors influencing sedimentary record. The site is therefore suitable for statistical testing of two populations mixing, outliers` detection and the like.

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2 Hejcman, Marek
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