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This paper presents the construction of an innovative high-temperature sensor based on the optical principle. The sensor is designed especially for the measurement of exhaust gases with a temperature range of up to +850 °C. The methodology is based on two principles-luminescence and dark body radiation. The core of this study is the description of sensing element construction together with electronics and the system of photodiode dark current compensation. An advantage of this optical-based system is its immunity to strong magnetic fields. This study also discusses results achieved and further steps. The solution is covered by a European Patent. [ABSTRACT FROM AUTHOR]

Grasslands are at risk of degradation due to unsustainable management practices and climate change. Here, we review the principal soil quality indicators (SQIs) to evaluate the sustainability of different grassland management practices globally. We discuss the importance of SQI assessment and the Soil Quality Minimum Dataset (MDS) specifically in the context of grasslands. We then review two potential solutions, the first of which is adopting grazing management, whereby sustainable grazing management plans (GMPs) offer great potential. The other solution is the development and adoption of novel grassland species, which may improve either drought resistance or infiltration rates, erosion and flooding. Sustainable grassland soil management can promote ecosystem service delivery and improve the resilience of the entire grassland ecosystem to anthropogenic change. [ABSTRACT FROM AUTHOR]

The field trial evaluating the effect of biochar on physical and hydro-physical properties of a Dystric Cambisol was carried out at the Research Grassland Station Vatín. The observed variants of the biochar experiment were as follows: 1) the control without biochar, 2) the biochar rate of 15 t/ha applied to the topsoil, 3) the biochar rate of 30 t/ha applied to the topsoil and 4) the biochar rate of 45 t/ha applied to the topsoil. It was found out that even the highest rate of biochar 45 t/ha did not affect saturated hydraulic conductivity of the topsoil at the depth of 0.05-0.20 m. When monitoring bulk density, it was confirmed that the biochar rate of 45 t/ha significantly reduced bulk density from 1218 kg/m³ to 1169 kg/m³. In the crop rotation without manure and clover growing the application of biochar at the rate of 45 t/ha resulted in the relevant decline in the average value of bulk density from 1197 kg/m³ to 1138 kg/m³. In the Norfolk crop rotation there were the inconclusive differences in bulk density. The rate of 45 t/ha had a highly noticeable impact on porosity. It increased from 53.75% (0 t/ha) to 55.60%. The biochar doses did not affect the value of field capacity. The application of biochar at the rate of 45 t/ha caused the significant increase in the average value of aeration from 31.90% to 34.45%. [ABSTRACT FROM AUTHOR]

The paper deals with the overview of fiber optic methods suitable for temperature measurement and monitoring. The aim is to evaluate the current research of temperature measurements in the interval from temperature close to 0 up to 1000°C. Since the measuring chain is a functional combination of optical methods, optical fiber properties, and other photonic elements together with control electronic circuits, it is necessary to find a suitable compromise between the chosen measurement method, measuring range, accuracy, and resolution. Optical fiber sensors can be used in cases where standard electrical measurement methods cannot be used. These may be areas with high electrical and magnetic interference or critical areas. Therefore, there is intensive development of optical and fiber optic methods based on blackbody and greybody radiation, luminescence, fiber Bragg gratings (FBGs), and interferometers. [ABSTRACT FROM AUTHOR]

Suppression effect of hemiparasites on grasses is a phenomenon, that can be utilized to increase biodiversity of various grassland systems. Host suitability, environmental effects, and hemiparasite abundance most likely influence the impact of parasitism on host height and biomass. However, the role of these factors is unclear in field conditions. We studied host suitability, establishment rates, and effects of a hemiparasitic plant Greater yellow rattle [ Rhinanthus alectorolophus (Scop.)] (RA) on canopy height and biomass of a grass tall fescue (Festuca arundinacea Schreb.) in five trials with manipulated fertilization conducted in golf roughs. Particularly, we examined how grass height and biomass changed with increasing hemiparasite abundance. On average, grasses (nine in total) were better hosts than legumes (four in total). Tall fescue belonged to the group of better hosts. The average establishment rate of Rhinanthus plants ranged from 4.4 to 24.8% regardless of fertilization treatments. In fertilization trials, Rhinanthus did not affect grass height but weakly suppressed grass biomass in non‐fertilized plots. The relationship between grass height/biomass and Rhinanthus abundance was best described by a logarithmic decay model. The suppressive effect tended to saturate (negative density dependence) in plots where the Rhinanthus abundance was very high. However, such high densities were quite rare and low Rhinanthus abundances were usually insufficient to substantially suppress grass growth. Our results indicate that we should aim for at least 50 Rhinanthus plants per 1 m2 to achieve desirable effects on biodiversity and that Rhinanthus performance will be better when nutrients are rather limiting. [ABSTRACT FROM AUTHOR]

Italian, annual and perennial ryegrasses are the most important grass species cultivated for seed production in the Czech Republic. The straw remaining after seeds threshing can be used as low quality forage, bedding material or as soil amendment. However, there are no comprehensive information concerning grass straw yields and quality in central Europe. The aim of this study was to investigate the Italian (IR) and perennial (PR) ryegrass straw yield and quality. These parameters were measured for two harvest years at two locations. IR did not provide statistically higher straw yield than PR (7.50 and 7.17 t.ha-1 respectively, p = 0.314), but dry matter (DM) content immediateliy after threshing was higher than for PR (0.42 and 0.38 respectively, p = 0.03). IR straw had the same content of ash and hemicellulose (mean 69.8 and 216 g.kg-1DM, p = 0.22 and 0.57), but less crude protein (64.1 and 81.4 g.kg-1DM, p = 0.003), more fibre (399 and 382 g.kg-1 DM, p = 0.02), NDF (656 and 629 g.kg-1 DM, p = 0.03) and ADF (442 and 412 g.kg-1 DM, p = 0.000) when compared with PR straw. Most of the parameters were affected by the year (with exception of crude protein) and by location (with exception of yield, DM content, ash and crude protein). There were no differences in mineral nutrient contents between species. The highest values were found in potassium (19.8 g.kg-1DM) what is comparable with average quality hay. Phosphorus, calcium and magnesium contents (1.42, 2.96 and 1.02 g.kg-1DM) were substantially lower than in hay. Data concerning ryegrasses straw yield and quality from the USA are comparable with our results and can be used for European conditions. [ABSTRACT FROM AUTHOR]

Visible Light Communication (VLC) technology uses white Light Emitting Diodes (LED) for providing illumination and communication at the same time. White LEDs have excellent illumination properties but their communication properties need improvement. This article proposes a way how to evade the communication limitations of white LEDs. A part of original white LED spectrum is suppressed by an optical filter. Then the suppressed part is replaced by another LED. The correct choice of suitable LED enables to reconstruct the original spectrum. This solution removes the limitations because the white LED emits continuously. Data are carried by the communication LED only. The evaluation of reconstruction of original white light is measurement of the colour coordinates x and y. Furthermore, the communication properties of this transmitter were tested and obtained results are shown in this paper. EVM parameter was measured. [ABSTRACT FROM AUTHOR]

The paper describes the original results of a comparative study of the standard seismic station vs. a novel interferometric sensor for civil engineering needs. The presented results showed that to implement seismic measurements using standard seismic stations, a method using a fiber optic interferometer may serve as an alternative. We presented time records and the frequency spectra obtained from experimental measurements of the dynamic response of the upper rock mass beneath passing tram vehicles (a total of 769 passes) over a period of five months of practical measurements under various climatic conditions. The fiber-optic sensor detected all phenomena at a 100% rate, and the recorded results were compared to the results from a standard seismic station. Both sets of results were recorded simultaneously and agreed significantly, especially in terms of frequency. With regard to time, all tram vehicle axles were detected in individual time records. With regard to frequency, the results detected in the bandwidth generally correlated to rail transport for individual types of tram vehicles. [ABSTRACT FROM AUTHOR]

Abstract: Plant variation in nutrient concentrations encompasses two major axes. The first is connected to nitrogen (N) and phosphorus (P), reflects growth rate and has been designated as the leaf economics spectrum (LES) while the second follows the gradient in calcium (Ca) and magnesium (Mg) and mirrors cell structural differences. Here, we tested in grasslands whether the sum Ca + Mg concentrations is a better indicator of digestibility than LES constituents. Structural equation modelling revealed that the total effect size of N (0.30) on digestibility was much lower than that of Ca + Mg (0.58). The N effect originated predominantly from sampling date (biomass ageing), while the Ca + Mg effect largely from phylogenetic composition (proportion of monocots). Thus, plant variation in partially substitutable divalent cations seems to play a significant role in biomass digestion by ruminants. This finding contests, together with litter decomposition studies, the prominent role of the LES for understanding both fundamental ecological processes. [ABSTRACT FROM AUTHOR]

The influence of atmospheric environment is fundamental for Free-Space Optical link (FSO). The atmosphere can significantly degrade the communication quality of FSO up to so low received power/RSSI level that it can lead to the loss of communication. For this reason, authors used a professional weather station built on site of FSO link for measurement of real atmospheric conditions such as wind speed, temperature, relative air humidity, air pressure and solar radiation. Random changing of these atmosphere parameters creates atmospheric turbulences, absorption and dispersion centers. It is necessary to specify the value of refractive index structure parameter cn2 because it determines the influence of atmosphere on the FSO. The first part of this article includes the theoretical calculation of cn2, there are used two models PAMELA and Macroscale-Meteorological model. The evaluation of the atmospheric influences and the RSSI value of received power level and also simulation of different types of modulation formats OOK-RZ, OOK-NRZ and BPSK in Optiwave is integral part of this article. [ABSTRACT FROM AUTHOR]

The objective of the current laboratory study was to assess the effects of a number of amendment materials and the depth of incorporation on water retention. 300 mm rootzone profiles were established in 150 mm diameter plastic cylinders over a 50 mm gravel drainage layer. Five amendment materials (sphagnum peat, compost, zeolite, TerraCottem and Stockosorb) were mixed with a medium-coarse sand at various rates. The upper rootzone layer (0–150 mm) included 50%, 100% and 150% of published or manufacturersã recommended rates of each amendment material. Three amendment rates were included in the lower rootzone layer (150–300 mm): pure sand, half the amendment rate of the top layer, and the same amendment rate as the top layer. The following measurements were made: water retention in individual layers, volumetric water content in the top layer (0–60 mm), shear strength, surface hardness, permanent wilting point. Water retention was significantly influenced by the different amendment materials. The most water retentive mixes were those containing peat and Stockosorb, whilst the least retentive contained the TerraCottem and the pure sand. The influence of amendment rate in the lower layer was less in comparison with the top layer. The incorporation of amendment materials in the lower rootzone had no significant effect on water retention in the upper rootzone but did increase the total water storage in the profile and this would have some implications for plant growth during drier periods. Rootzone mixes containing peat and compost had the highest shear strength whilst the Stockosorb gave the lowest strength because the expansion of the polymer reduced rootzone density and therefore the degree of contact between the sand particles. The hardest surface was measured when zeolite was used and the softest surfaces resulted from the use of Stockosorb. [ABSTRACT FROM PUBLISHER]

Permanent grasslands cover 34% of the European Union's agricultural area and are vital for a wide variety of ecosystem services essential for our society. Over recent decades, the permanent grassland area has declined and land use change continues to threaten its extent. Simultaneously, the management intensity of permanent grasslands increased. We performed a systematic literature review on the multifunctionality of permanent grasslands in Europe, examining the effects of land use and management on 19 grassland ecosystem service indicators. Based on the evidence in 696 out of 70,456 screened papers, published since 1980, we found that both land use change and intensification of management decreased multifunctionality. In particular, preventing conversion of permanent grasslands to croplands secured the delivery of multiple ecosystem services. A lower management intensity was associated with benefits for biodiversity, climate regulation and water purification, but impacted the provision of high-quality animal feed. Increasing the number of species in the sward enhanced multifunctionality of permanent grassland without significant trade-offs such as losses in production. Our review covered many aspects of land use, management and ecosystem services, but we also identified areas with no or only few studies. The most prominent gaps were related to comparisons between permanent and temporary grasslands, and effects of management practices on the provision of cultural values, and on erosion and flood control. We suggest that, despite apparent changes in human dietary preferences, the protection of permanent grasslands in Europe must be prioritised. At the same time, considering the need to reduce ruminant livestock's contribution to climate change, the time seems ripe to increase support for low-intensity grassland management to optimise the provision of essential ecosystem services from Europe's permanent grasslands. • In recent decades, Europe's permanent grassland area has declined and land use change continues to be a threat. • We performed a systematic literature review on ecosystem services delivery from permanent grasslands. • Our findings are based on evidence in 696 out of 70,456 screened papers on 19 ecosystem service indicators. • Land use change and intensification decrease the multifunctionality of permanent grasslands. • Despite calls to reduce meat and dairy consumption, the protection of permanent grasslands has to be prioritized. [ABSTRACT FROM AUTHOR]