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Water-use efficiency of winter wheat under heat and drought stress
Hlaváčová, Marcela; Klem, Karel; Novotná, Kateřina; Rapantová, Barbora; Urban, Otmar; Hlavinka, Petr; Smutná, P.; Horáková, V.; Škarpa, P.; Trnka, Miroslav
2017 - English
Because such extreme weather events as dry spells and heat waves are expected to occur more frequently\ndue to climate change, the issue of appropriate water management for sustainable agricultural production\nis increasingly important. This study focuses on wheat, the second most widely grown cereal in the world\nand the most common cereal in European countries. The study assesses the effects of short periods (3 and\n7 days) of high temperatures (26°C as a control, 32°C, 35°C, and 38°C as daily temperature maxima from\n12:00 to 14:00) and drought stress at different developmental stages (DC 31 – beginning of stem elongation,\nDC 61 – flowering, and DC 75 – early grain filling) on water-use efficiency (WUE) in winter wheat\ncultivar Tobak. This cultivar is one of the most widespread winter wheat cultivars in Czech Republic fields.\nThe analysis of WUE showed that the cv. Tobak plants were able to withstand drought stress conditions\nthrough increased WUE. In contrast, wheat plants were stressed more markedly if exposed to higher temperatures\nand drought in combination. Generally, the wheat plants were most sensitive to drought at DC\n31.
Keywords:
winter wheat; drought stress; water-use efficiency
Available at various institutes of the ASCR
Water-use efficiency of winter wheat under heat and drought stress
Because such extreme weather events as dry spells and heat waves are expected to occur more frequently\ndue to climate change, the issue of appropriate water management for sustainable agricultural ...
Exploring knowledge and attitudes towards climate change among a study sample from Khartoum State, Sudan
Alhuseen, Ahmed; Kozová, M.; Ismaeel, I.; Cudlín, Pavel
2017 - English
In spite of an adaptation plan endorsed by the city’s authorities, Khartoum State, the capital of Sudan, has repetitively\nexperienced a series of ravaging climate variability impacts. As in similar cases elsewhere, there are\nindications of financial and institutional incapacities and shortfalls to run the adaptation process, as well as\nlack of public knowledge about climate change. It has been argued that having well-informed communities in\nsome developing countries has reduced vulnerability and exposure to climate-origin disasters. Aiming to provide\nquantitative insight into the community’s knowledge and attitudes about climate change, this study presents\nthe results of a survey carried out in 2014 in a simple random sample of Khartoum State residents encompassing\n395 households. Data analysis showed that >75% of the respondents were aware of both the term “climate\nchange” and its main causes. Due to certain cultural and religious factors, however, familiarity with its\nassociated risks was less (25–75%). Moreover, knowledge regarding the ongoing government efforts, leading\ninstitutions, participating non-government organizations, and beliefs about the capability of Khartoum State\nauthorities to adapt the city to the foreseen impacts was found to be low (<25%). Of the respondents, 49% believed\nthat both human activities and God are responsible for causing climate change. Seventy-nine per cent\nof the respondents were interested in acquiring information about climate change, but only 55.3% frequently\nobtain it. Although 79% of the respondents would agree or strongly agree to pay in order to mitigate climate\nchange, 50.4% believed that nothing had been done by local government to mitigate that change. The study\nprovides unprecedented insight into knowledge and attitudes towards climate change among Khartoum State\nhouseholds. The results can be used by city authorities and government politicians to support ongoing adaptive\nprocedures and decision-making while narrowing the knowledge gap concerning climate change risks.
Keywords:
towards climate change; Sudan
Available at various institutes of the ASCR
Exploring knowledge and attitudes towards climate change among a study sample from Khartoum State, Sudan
In spite of an adaptation plan endorsed by the city’s authorities, Khartoum State, the capital of Sudan, has repetitively\nexperienced a series of ravaging climate variability impacts. As in similar ...
Jak ovlivňují magnetické kapaliny klíčivost a počáteční růst bělohořčice seté (Leucosinapis alba (L.) spach)
Šerá, B.; Vlčková, V.; Maděrová, Zdeňka
2017 - Czech
In this research we investigated toxicity of three types of water based magnetic iron fluids (acidic pH 2.7, alkaline pH 6.4, and citrate ferrofluids pH 6,4) at four concentrations 0.10, 0.25, 0.5 and 1.00 mg of nanoparticles of magnetic iron oxides in 1 ml ground fluids (surfactant and solvent). Seed germination and ground growth characteristics on seed dressing (used white mustard) were investigated. Significant toxicity was found at acidic ferrofluid, on the other hand a neutral effect was found at citrate ferrofluid. Values of investigated characteristics at alkaline ferrofluid brought interesting findings. The higher concentrations of iron oxides were toxic (0.5 and 1.00 mg/ml) and the lower ones (0.10 and 0.25 mg/ml) like partly eliminated the influence of the effect of ground fluids. Text přináší výsledky z testování toxicity tří typů vodních magnetických kapalin (kyselý pH 2,7 citrátový pH 6,4 a alkalický ferrofluid pH 11,8) při koncentracích 0,10, ,25, 0,5 a 1,00mg nanočástic magnetických oxidů železa v 1 ml příslušné nosné kapaliny (surfaktant a rozpouštědlo). Sledovány byly klíčivost a základní charakteristiky počátečního růstu u namořených semen bělohořčice bílé. Významná toxicita byla zajištěna u kyselého ferrofluidu, naopak neurální vliv byl zaznamenán u citrátového ferrofluidu. Hodnoty sledovaných charakteristik a alkalického ferrofluidu přinesly zajímavá zjištění. Vyšší koncentrace byly toxické (0,5 a 1,00 mg/ml) a nižší koncentrace oxidů železa (0,10 a 0,25 mg/ml) částečně odbouraly negativní vliv účinku samotného nosného média (terametylamonium hydroxid).
Keywords:
iron-oxide nanoparticles; hyperthermia; composite; water; magnetic fluid; iron nanoparticles; testing of toxicity; grow seed; seed dressing
Available at various institutes of the ASCR
Jak ovlivňují magnetické kapaliny klíčivost a počáteční růst bělohořčice seté (Leucosinapis alba (L.) spach)
In this research we investigated toxicity of three types of water based magnetic iron fluids (acidic pH 2.7, alkaline pH 6.4, and citrate ferrofluids pH 6,4) at four concentrations 0.10, 0.25, 0.5 and ...
COMPARISON OF ACTUAL EVAPOTRANSPIRATION FROM ALEXI AND SOILCLIM MODELS
Jurečka, František; Hlavinka, Petr; Lukas, Vojtěch; Trnka, Miroslav; Anderson, M.; Hain, C.; Balek, Jan; Bláhová, Monika; Žalud, Zdeněk
2017 - English
Actual evapotranspiration (ETa) determined by the Atmosphere-land Exchange Inverse (ALEXI) model and water balance model SoilClim was compared for selected districts of the Czech Republic. The ALEXI model uses the land surface temperature (LST) from remote sensing and provides information on ETa and subsequently the surface moisture status. The SoilClim is a dynamic model of watcr content in soil and represents a model based on water balance approach. The current version of the model is able to estimate the value of ETa, as well as soil moisture content in two layers of the soil profile. Investigated period of ETa comparison were years 2014 and 2015. Especially the year 2015 had a special relevance due to the significant summer drought that occurred in CR. Model performance was compared for the period when changes in vegetation are most significant from April to August. Week sums of ETa from both models were compared at the district level for Vysodina, JihomorayskY and Olomouck, regions. The ETa values were generally higher from ALEXI as compared to SoilClim. ALEXI values were in some cases even two or three time higher. Moreover, the seasonal dynamics showed sometimes opposite trends. As this is a pilot testing of ALEXI based ETa in the conditions of Central Europe and show large differences as compared to well established methods, more detailed testing is required prior drawing any general conclusions.
Keywords:
fluxes; evapotranspiration; drought; remote sensing; land surface temperature; water balance
Available at various institutes of the ASCR
COMPARISON OF ACTUAL EVAPOTRANSPIRATION FROM ALEXI AND SOILCLIM MODELS
Actual evapotranspiration (ETa) determined by the Atmosphere-land Exchange Inverse (ALEXI) model and water balance model SoilClim was compared for selected districts of the Czech Republic. The ALEXI ...
Interactive effect of UV radiation and CO2 treatment on extractable volatile organic compounds from European beech leaves
Večeřová, Kristýna; Pernicová, N.; Klem, Karel; Urban, Otmar
2017 - English
The main objective of this experiment was to investigate the combined effect of different UV treatments\nand elevated CO2 concentration on monoterpene and methyl salicylate (MES) content in leaves of\nEuropean beech during the growing season. Plants were grown under ambient (AC, 400 μmol mol–1) and\nelevated (EC, 700 μmol mol–1) CO2 concentrations and three UV radiation treatments (ambient – UVamb,\nexcluded – UV-, and enhanced – UV+). Leaves collected from July to September were extracted in cold\nheptane to determine volatile organic compounds content using gas chromatography. Our results show\nthat AC plants had higher total content of extractable monoterpenes and MES than did EC plants over\nthe whole growing season and irrespective of UV treatment. Limonene, 2-bornene, and ester MES were\nthe most abundant volatile compounds in beech leaves. The highest contents of 2-bornene and MES were\nfound under the UV- treatment and AC. Contents of α-pinene, β-pinene, and carene decreased during the\ngrowing season while the content of limonene increased.
Keywords:
UV radiation; CO2 treatment; European beech
Available at various institutes of the ASCR
Interactive effect of UV radiation and CO2 treatment on extractable volatile organic compounds from European beech leaves
The main objective of this experiment was to investigate the combined effect of different UV treatments\nand elevated CO2 concentration on monoterpene and methyl salicylate (MES) content in leaves ...
Predicting light use efficiency using optical vegetation indices at various time scales and environmental conditions
Kováč, Daniel; Ač, Alexander; Veselovská, Petra; Dreveňáková, Petra; Rapantová, Barbora; Klem, Karel
2017 - English
This study presents data points acquired during 2 years of measuring optical properties and gas-exchange\ncharacteristics of European beech (Fagus sylvatica) and Norway spruce (Picea abies) tree species in controlled\nenvironments. The observed statistical relationships between 105 pairs of selected optical parameters\n(i.e. photochemical reflectance index [PRI], ΔPRI, and normalized difference between wavebands R690\nand R630 [where R is a reflectance at a subscripted wavelength]) and light use efficiency (LUE) were considered\nat assumed different canopy leaf area index, changing pigments stoichiometrics, and daily changing\ndynamics of environmental conditions. Our measurements suggested that consistency of the LUE estimation\nusing PRI may be disrupted by acclimation responses of plants that reduce energetic carriers for\nuse in photosynthetic CO2 uptake and the xanthophyll cycle. Also, a changing chlorophylls-to-carotenoids\nratio tends to interrupt the PRI–LUE relationship. ΔPRI showed sensitivity to leaf area index of the measured\ntrees that complicated leaf-level estimation of LUE. The most consistent assessment of LUE was\nachieved using the chlorophyll fluorescence detecting ratio (R690 – R630)/(R690 + R630).
Keywords:
vegetation indices; various time scale; environmental conditions
Available at various institutes of the ASCR
Predicting light use efficiency using optical vegetation indices at various time scales and environmental conditions
This study presents data points acquired during 2 years of measuring optical properties and gas-exchange\ncharacteristics of European beech (Fagus sylvatica) and Norway spruce (Picea abies) tree ...
Application of multispectral remote sensing indices for sensing indices for estimating crop yields at field level
Jurečka, František; Lukas, Vojtěch; Hlavinka, Petr; Semerádová, Daniela; Fischer, Milan; Žalud, Zdeněk; Trnka, Miroslav
2017 - English
Remote sensing can be used for yield estimation prior to harvest and can replace or complement classical\nways of estimating crop yields. This study was undertaken in Polkovice, located in the Czech Republic’s\nHaná region. For 2015 and 2016, two data sets of satellite imagery were used: the Moderate Resolution\nImaging Spectroradiometer and the Landsat 8. Vegetation indices from satellites were compared with crop\nyields at the level of land blocks. Winter wheat and spring barley yield data, representing crops planted\nover the analysed period, were used for the comparison. The results of the index–yield comparison showed\nthat vegetation indices from remote sensing data provide reliable information for yield estimation prior to\nharvest. Indices are also able to evaluate the spatial variability of a crop within the field. The results showed\nthat remote sensing data need to have detailed spatial resolution in order to provide reasonable information\nabout yield at such a detailed level.
Keywords:
remote sensing; crop yield; vegetation
Available at various institutes of the ASCR
Application of multispectral remote sensing indices for sensing indices for estimating crop yields at field level
Remote sensing can be used for yield estimation prior to harvest and can replace or complement classical\nways of estimating crop yields. This study was undertaken in Polkovice, located in the Czech ...
Látkové toky v amfibolitovém povodí Na zeleném u Vodního díla Mariánské Lázně
Krám, Pavel; Veselovský, F.; Čuřík, Jan; Myška, Oldřich
2017 - Czech
Příspěvek se zabývá hydrologií a hydrochemií povodí Na zeleném zalesněném smrkovým lesem rostoucím na podloží, tvořeném kambizemí na amfibolitu. Toto povodí se vyznačuje díky bazickému (zásaditému) podloží poměrně příznivými hydrochemickými poměry pro terestrickou a akvatickou biotu. Povodí se vyznačuje efektivní neutralizací kyselé atmosférické depozice do smrkového ekosystému a to hlavně díky chemickému zvětrávání dvoumocných bazických kationtů, vápníku a hořčíku. Roční průměrný srážkový úhrn do povodí Na zeleném byl za sledované pětileté období 790 mm a průměrný povrchový odtok v posledních dvou letech byl 193 mm. Odtok se pohyboval ve sledovaných letech mezi 24 a 27 % ročních srážkových vstupů do povodí. V povodí se akumuluje jen méně než 20 % celkového dusíku ze srážek na volné ploše. Zhruba 36% dusíku povodí opouští povrchovým odtokem, zhruba z poloviny ve formě dusičnanů a z poloviny ve formě rozpuštěného organického dusíku. The paper is about hydrology and hydrochemistry of the Na Zelenem catchment forested by spruce stands which growso n substrate formed by Cambisol on amphibolite. This catchment is characterized by fairly favorable hydrochemical conditions for terrestrial and aquatic biota. The catchment is able to effectivetely neutralize incoming acidic atmopheric deposition mainly due to chemical weathering reactions involving divalent base cations, calcium and magnesium. Mean average precipitation to the Na Zelenem catchment was 790 mm/yr based od 5 year studied period and mean surface runoff was 193 mm/yr in the last two years. Runoff was between 24 and 27% of annual precipitation input to the catchment in the last two years. The catchment accumulated less than 20% of total nitrogen input in bulk precipitation. About 36% of nitrogen left the catchment via surface runoff. About half of the nitrogen output was in the form of nitrate and about half in the form of dissolved organic nitrogen.
Keywords:
small forest basins; atmospheric deposition; surface water; fluxes; nitrates; dissolved organic nitrogen; acidity buffers; basic subsoil; spruce spruce
Available at various institutes of the ASCR
Látkové toky v amfibolitovém povodí Na zeleném u Vodního díla Mariánské Lázně
Příspěvek se zabývá hydrologií a hydrochemií povodí Na zeleném zalesněném smrkovým lesem rostoucím na podloží, tvořeném kambizemí na amfibolitu. Toto povodí se vyznačuje díky bazickému (zásaditému) ...
Měřené a modelované toky troposferického ozonu v horském porostu smrku ztepilého
Juráň, Stanislav; Zapletal, Miloš; Večeřa, Zbyněk; Cudlín, Pavel; Urban, Otmar
2017 - Czech
Toky troposférického ozonu (O3) byly měřeny ve smrkovém lese na Bílém Kříži, České republika pomocí metody vířivé kovariance. Koncentrace O3 byla měřena současně v profilu korunové vrstvy studovaného porostu (ve výšce 7 m, 25 m a 30 m nad povrchem země) pomocí analyzátorů ozonu APOA-370 (Horiba, Japan). Na základě zjištěného koncentračního gradientu byly následně modelovány toky ozonu pomocí Inverzního Lagrangianova Transportního Modelu (Raupach, 1989). Dále byly toky ozonu modelovány pomocí rezistenčního modelu, který vychází z výpočtu depozičních rychlostí ozonu na základě rezistenční analogie. Tok ozonu stanovený pomocí vířivé kovariance vykazuje nejvyšší průměrný denní tok 1,19 nmol m-2 s-1 a nejnižší -0,75 nmol m-2 s-1. Studovaný lesní porost byl čistým sinkem pro ozon a to ve výši 7,14 mmol m-2 za den (=0,343 g m-2 za den). Nejvyšší rychlost emise ozonu (kladná hodnota toku) byla pozorována během poledních hodin, kdy za nízkých teplot byly zavřené průduchy, a díky dostatečné intenzitě slunečního záření docházelo k tvorbě ozonu. Oba modely se ukázaly jako problematické v přesném stanovení toku během přechodu ze podzimního do zimního období. Tropospheric ozone fluxes (O3) were measured in Norway spruce forest at Bily Kriz, Czech Republic by eddy covariance technique. Within-canopy concentration gradient was measured by APOA-370 analysers (Horiba, Japan) in 7m, 25m and 30m above ground. Fluxes of O3 were modelled from the concentration gradient by applying Inverse Lagrangian Transport Model (Raupach, 1989). Next, O3 fluxes were modelled on the basis of resistent analogy. Ozone flux measured by eddy covariance technique amounted up to 1.19 nmol m-2 s-1 on daily average and the lowest -0.75 nmol m-2 s-1. Studied forest stand was net sink for ozone in 7.14 mmol m-2 per day (=0.343 g m-2 per day). The highest ozone emission peaked during noon hours, suggesting closure of stomata due to low air temperature and ozone production due to sufficient radiation. Both models proved to be imprecise when compared to measured data in autumn-winter transition period.
Keywords:
Ozone flux; modelling; Norway spruce; eddy covariance
Available at various institutes of the ASCR
Měřené a modelované toky troposferického ozonu v horském porostu smrku ztepilého
Toky troposférického ozonu (O3) byly měřeny ve smrkovém lese na Bílém Kříži, České republika pomocí metody vířivé kovariance. Koncentrace O3 byla měřena současně v profilu korunové vrstvy studovaného ...
Růst zimních teplot vzduchu v České republice v letech 1961-2010
Střeštík, Jaroslav; Rožnovský, J.; Štěpánek, Petr; Zahradníček, Pavel
2017 - Czech
Na základě analýzy průměrných měsíčních teplot vzduchu za období 1961 až 2010 můžeme konstatovat, že na našem území je statisticky prokázán jejich nárůst. Ovšem v jednotlivých ročních obdobích je toto zvýšení rozdílné, což platí i územně, tedy jsou rozdílné hodnoty nárůstu v Čechách a na Moravě. V létě rostou průměrné měsíční teploty vzduchu více na Moravě, kde je vyšší počet stanic se zvýšením přes 1°C, než v Čechách. Toto platí i pro jaro, ale rozdíl je mezi Čechami a Moravou není tak vysoký, na podzim je ještě nižší. Naopak v zimě je vyšší nárůst teploty vzduchu v Čechách, kde na většině stanic jde o zvýšení o více jak 0,5°C. Na Moravě je u většiny stanic nárůst kolem 0,3 až 0,4°C, u daleko menšího počtu stanic je zvýšení vyšší. Rozdíly ve zvyšování průměrné teploty vzduchu jsou i mezi jednotlivými měsíci zimy. Nejvýraznější nárůsty jsou v lednu, kde na části stanic v Čechách je to i více jak 1°C, na Moravě takových nárůstů není dosaženo, část stanic má zvýšení pod 0,8°C. V prosinci a v únoru je zvýšení podstatně nižší. Vzhledem k očekávanému růstu průměrných teplot vzduchu lze však očekávat, že v příštích desetiletích bude výskyt teplých zim vyšší. Růst teploty vzduchu v zimním období bude mít nepříznivé dopady v zemědělství.\n Based on the analysis of average monthly air temperatures between 1961 and 2010 it can be statistically proven that there is an increasing trend. The actual level of increase, however, is different for each season and is also specific for a particular region – there are differences between Bohemia and Moravia. In the summer, the average monthly air temperatures rise more significantly in Moravia, where there is a higher number of stations with increase of over 1°C compared to Bohemia. This is also true for the spring, for which the difference is not so profound, and is yet smaller in the autumn. In contrast, in the winter there is a more significant increase in Bohemia, where most stations show an increase of over 0.5°C. In Moravia the increase is usually only around 0.3 to 0.4°C. Differences between the increases of average air temperature can also be seen across the individual winter months. Highest increase was found in January, where some stations in Bohemia show an increase of over 1°C, a value that was not observed in Moravia, where some stations have an increase of less than 0.8°C. In December and February, the level of increase in general is much smaller. However, given the predicted increase of air temperatures in the future in general, it can be expected that in the upcoming decades the number of warm winters will increase. Such increase of air temperatures in the winter is likely to have negative impacts for the agriculture.
Keywords:
global warming; seasons; winter air temperatures; frosts; drought
Available at various institutes of the ASCR
Růst zimních teplot vzduchu v České republice v letech 1961-2010
Na základě analýzy průměrných měsíčních teplot vzduchu za období 1961 až 2010 můžeme konstatovat, že na našem území je statisticky prokázán jejich nárůst. Ovšem v jednotlivých ročních obdobích je toto ...
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