Národní úložiště šedé literatury Nalezeno 26 záznamů.  1 - 10dalšíkonec  přejít na záznam: Hledání trvalo 0.00 vteřin. 
Monitoring of water use, druought and yield impacts of winter wheat using imaginery from satellites
Jurečka, František ; Anderson, M. ; Hlavinka, Petr ; Semerádová, Daniela ; Trnka, Miroslav ; Hain, C. ; Gao, F. ; Yang, Y. ; Žalud, Zdeněk
Remote sensing can be very useful tool for drought monitoring, providing valuable information about yield-limiting moisture conditions and crop response under current climate conditions. In this study the Atmosphere-land Exchange Inverse (ALEXI) model was used. The ALEXI model uses the morning surface temperature (LST) rise and provides information on the surface moisture status. In this paper correlations between yields and satellite indicators of crop water use or evapotranspiration (ET) were studied for the period 2002-2014. Correlations were studied for winter wheat at district scale in Vysocina, Jihomoravsky and Olomoucky regions since winter wheat is one of the traditional and most important crops grown in these regions. The Evaporative Stress Index (ESI) was used for these correlations as an ET-based index. Time series of Pearson correlation coefficient (r) computed between ESI and winter wheat yields at district scale were analysed. Strongest correlations are associated with districts within the Southern Moravian lowlands in Jihomoravsky and Olomoucky region, where frequency of occurrence of severe drought was highest over the period of record. Severe drought resulted in significant yield impacts, particularly in years 2003 and 2012. Correlations tend to be lower over the highlands districts of Vysocina and surroundings. In these districts, yields are more temperature than moisture limited and were more stable over the period of record.
Agroklimatická analýza výhledů změn výchozích výrobních podmínek pro zemědělské subjekty a související dopady do systému bonitace půdy
Trnka, Miroslav ; Hlavinka, Petr ; Balek, Jan ; Semerádová, Daniela ; Dubrovský, Martin ; Štěpánek, Petr ; Žalud, Zdeněk
Předmětem této zprávy je vyhodnocení analýz zpracovaných v rámci smluvní výzkumné spolupráce zadané v rámci řešení projektu číslo EHP-CZ02-OV-1-039-2015 s názvem „Komplexní plánovací, monitorovací, informační a vzdělávací nástroje pro adaptaci území na dopady klimatické změny s hlavním zřetelem na zemědělské a lesnické hospodaření v krajině“ financovaného z fondu EHP 2009 - 2014 programu CZ02 - Biodiverzita a ekosystémové služby/. Studie se zaměřuje na území Jihomoravského kraje (JmK) a navazuje na zprávu hodnotící dopady očekávaných klimatických podmínek zpracovanou pro výše uvedený projektu v říjnu 2016. Podobně jako předchozí studie byla i tato část zpracována na základě 5 vybraných globálních cirkulačních modelů (GCM) a to pro dva emisní scénáře a období 2021-2040. Protože detailní popis použitých scénářů obsahuje předešlá zpráva omezujeme se v tomto textu pouze na nejdůležitější výstupy relevantní pro JmK.
Drought monitor for the Czech Republic-www.intersucho.cz
Trnka, Miroslav ; Hlavinka, Petr ; Semerádová, Daniela ; Balek, Jan ; Možný, M. ; Štěpánek, Petr ; Zahradníček, Pavel ; Hayes, M. ; Eitzinger, Josef ; Žalud, Zdeněk
Because drought and its impacts are among the worst hydrometeorological extremes (including also Central European conditions), the aim of this paper is to describe the core and use of the Integrated drought monitoring system for the Czech Republic. Land-use, information about soil, vegetation characteristics and meteorological data are used as inputs to validated water balance SoilClim model, which is applied for estimates of actual and reference evapotranspiration and water saturation of the soil profile in % or soil moisture content in mm. Moreover the prognosis of expected soil moisture (based on probabilistic analysis) is calculated for next 1, 2, 4 and 8 weeks. Main results are weekly updated in form of drought occurrence maps, which are published in spatial resolution 500 m for whole territory of the Czech Republic and for all its 76 districts separately. Final maps with detail comments are available at drought topic dedicated web page (ANONYM 3 2014).
Detection of drought events using combination of satellite data and soil moisture modelling
Semerádová, Daniela ; Trnka, Miroslav ; Hlavinka, Petr ; Balek, Jan ; Bohovič, Roman ; Tadesse, T. ; Hayes, M. ; Wardlow, B. ; Žalud, Zdeněk
The use of satellite data offers a potentially well usable tool to accurate drought monitoring. The study examines the space-time possibility of agricultural drought detection using freely available data from the MODIS instrument onboard Terra and Aqua satellites that reflects vegetation condition. Vegetation greenness metrics used in this study are based on the spectral reflectance curves in the visible red and near-infrared part of the spectrum and are expressed in relation to the average for the period of 2000-2014. The results are presented in weekly time step for the whole area of the Czech Republic, and are compared to the drought monitor system, based on the SoilClim dynamic model for soil water content estimates. These data, as well as other parameters, such as soil properties and land use, are integrated at 500 meters spatial resolution.
Zpracování částí II. etapy Generelu vodního hospodářství ČR
Trnka, Miroslav ; Dumbrovský, M. ; Růžek, P. ; Žalud, Zdeněk ; Drbal, J. ; Hlavinka, Petr ; Novotný, I. ; Vopravil, J. ; Chuchma, F. ; Vizina, P.
Předmětem této zprávy je zpracování výsledků výzkumu zadaného v rámci smluvní spolupráce Ústavu výzkumu globální změny (zpracovatel) a Mendelovy univerzity v Brně (zadavatel), který byl zpracován ve spolupráci s dalšími výzkumnými partnery. Zpráva zpracovává tzv. II. etapu Generelu vodního hospodářství ČR s ohledem na probíhající klimatické změny.
Bilanční hodnocení dostupných vodních zdrojů a vláhových potřeb v rámci vymezených "závlahových okrsků"
Trnka, Miroslav ; Hlavinka, Petr ; Balek, Jan ; Semerádová, Daniela ; Dubrovský, Martin ; Štěpánek, Petr ; Vizina, A. ; Hanel, M. ; Žalud, Z. ; Lukas, V. ; Dumbrovský, M. ; Růžek, P. ; Daňhelka, J. ; Chuchma, F. ; Novák, P. ; Novotný, I. ; Pavlík, F.
Předmětem této zprávy je zpracování výsledků výzkumu zadaného v rámci smluvní spolupráce Ústavu výzkumu globální změny (zpracovatel) a Státního pozemkového úřadu (zadavatel), který byl zpracován ve spolupráci s dalšími výzkumnými partnery. Zpráva se zabývá bilančním hodnocením dostupných vodních zdrojů a vláhových potřeb v rámci vymezených "závlahových okrsků" České republiky s ohledem na probíhající klimatické změny.
Komplexní přístup pro monitorování a zmírnění dopadů sucha v regionu jižní Moravy
Žalud, Zdeněk ; Trnka, Miroslav ; Hlavinka, Petr ; Semerádová, Daniela ; Balek, Jan
Hlavním cílem projektu bylo provozovat aktuální monitoring sucha na území Jihomoravského kraje (JMK) a identifikovat konkrétní suchem ohroženou lokalitu vhodnou pro realizaci opatření ke zlepšení jejich ekosystémových produkčních i mimoprodukčních funkcí. K dosažení hlavního cíle byly realizovány následující cíle dílčí: 1.Průběžně (týdně) monitorovat okresy JMK. 2. Vytvářet a publikovat předpovědi sucha pro JMK. 3. Sledovat suché epizody na území JMK a posoudit jejich dopady na polní produkci.
Effect of high temperature and water shortage stresses duration during anthesis on the selected winter wheat yield formation components
Hlaváčová, Marcela ; Rapantová, Barbora ; Novotná, Kateřina ; Klem, Karel ; Hlavinka, Petr ; Trnka, Miroslav
The aim of this study was to assess the effect of drought and high temperatures on Tobak winter wheat variety during one of the most sensitive developmental stage (anthesis) from the viewpoint of harvest index (HI) and spike productivity (SP). The 5 growth chambers (where the plants were exposed to these stress factors) were used for these purposes. The various protocols consisting in photosynthetically active radiation (PAR) course, relative air humidity (RH) and daily temperature courses were run. The plants were divided into 2 groups within each growth chambers: (1) Drough-stressed (Dry) and (2) well-watered (Wet). Two lengths of stresses duration were tested: 3 and 7 days. The plants were exposed to ambient weather conditions up to the full maturity after stresses exposition within the growth chambers. Subsequently, the plants were harvested manually and HI and SP were evaluated. The statistical analyses showed that the effect of each stress factor separately was statistically significant both for HI and SP14, nevertheless, these two factors interaction was statistically significant only in the case of HI.
Effect of drought stress on selected winter wheat yield formation components within pot and field experiimental design
Hlaváčová, Marcela ; Pohanková, Eva ; Klem, Karel ; Hlavinka, Petr ; Trnka, Miroslav
The object of this study was to find out what is the behaviour of the same winter wheat variety (Bohemia) plants cultivated within pot and field experiment. Therefore, the main aim of this study was to verify (based on the pot experiment results) whether the pot experiment (that is limited by the soil area) does not substantially affect plant reactions. The pot experiment was carried out in growth chambers where daily temperature course, relative humidity (RH) and photosynthetically active radiation (PAR) were set via protocols. The pots were exposed to the drought stress for 14 days with the daily maximum temperature 26 °C from noon to 2 p.m. The pots were split into 2 groups: (1) Dry where the soil moisture within pots were maintained below 30% of the maximum water holding capacity, (2) Wet where the soil moisture did not decrease below 70% of the maximum water holding capacity. The plants within Wet variant were considered as a control group. The pots were placed onto the concrete floor of a vegetation hall (where the plants were exposed to the weather conditions) prior and after stress regime exposition. The field experiment was conducted within experimental station in Bystřice nad Pernštejnem belonging to the Bohemian-Moravian Highlands in the Czech Republic. The drought stress was established through the transparent roofs installed above plants’ tops level in the field. The control experimental plot without roofs was nearby there as well. The plants were harvested when the full maturity was reached and the selected yield formation components were evaluated.
Crop yield estimation in the field level using vegetation indicies
Jurečka, František ; Hlavinka, Petr ; Lukas, Vojtěch ; Trnka, Miroslav ; Žalud, Zdeněk
Remote sensing can be very useful tool for agriculture management. In this study, remote sensing methods were applied for yield estimation in the field level. There were compared remote sensing data together with yield data obtained from the field. The study area is located in Polkovice in Olomoucký region and a crop planted there in the year 2016 was spring barley as one of most important crops grown in the region. The study area in Polkovice is located at lower elevations with intensive crop production and is climatologically warmer and drier than other areas of the Czech Republic. Year 2016 was the first year when the harvest device has been used for yield analysis in this study area. The output of this method is the yield map displaying the amount of crop harvested in the particular place in the field. The yield data from the field were then compared with remote sensing data in the form of vegetation indices. Two of them were used for comparison – Normalized Difference Vegetation Index (NDVI) and a two-band Enhanced Vegetation Index (EVI2). These indices have been often used for yield estimation in different studies but mostly in larger scales. This study investigates use of NDVI and EVI2 at more detailed scale while using various remote sensing methods. Comparisons show that remote sensing data can provide accurate estimation and can be used for yield forecasting or supplement traditional ways of yield estimation. Results of the study show that yield-index correlations are stronger for satellite data than for the drone data. NDVI showed slightly stronger correlations than EVI2. Strongest correlations between vegetation indices and yields were found for NDVI from Sentinel 2.

Národní úložiště šedé literatury : Nalezeno 26 záznamů.   1 - 10dalšíkonec  přejít na záznam:
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