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Reliability of regional crop yield predictions in the Czech Republic based on remotely sensed data
Hlavinka, Petr; Semerádová, Daniela; Balek, Jan; Bohovič, Roman; Žalud, Zdeněk; Trnka, Miroslav
2015 - anglický
Vegetation indices sensed by satellite optical sensors are valuable tools for assessing vegetation conditions including field crops. The aim of this study was to assess the reliability of regional yield predictions based on the use of the Normalized Difference Vegetation Index and the Enhanced Vegetation Index derived from the Moderate Resolution Imaging Spectroradiometer aboard the Terra satellite. Data available from the year 2000 were analysed and tested for seasonal yield predictions within selected districts of the Czech Republic. In particular, yields of spring barley, winter wheat, and oilseed winter rape during 2000–2014 were assessed. Observed yields from 14 districts were collected and thus 210 examples (15 years within 14 districts) were included. Selected districts differ considerably in soil fertility and terrain configuration and represent a transect across various agroclimatic conditions (from warm/dry to relatively cool/wet regions). Two approaches were tested: 1) using 16-day temporal composites of remotely sensed data provided by the United States Geological Survey, and 2) using daily remotely sensed data in combination with an originally developed smoothing method. Yields were predicted based on established regression models using remotely sensed data as an independent parameter. In addition to other findings, the impact of severe drought episodes within vegetation was identified and yield reductions at a district level were predicted. As a result, those periods with the best relationship between remotely sensed data and yields were identified. The impact of drought conditions as well as normal or above-normal yields of the tested field crops were predicted using the proposed method within the study region up to 30 days prior to harvest.
Klíčová slova:
crop yield predicitions; Czech Republic; remotely sensed data
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Reliability of regional crop yield predictions in the Czech Republic based on remotely sensed data
Vegetation indices sensed by satellite optical sensors are valuable tools for assessing vegetation conditions including field crops. The aim of this study was to assess the reliability of regional ...
Foliar application of zinc reduces the risk of drought stress on poppy (Papaver somniferum L.)
Škarpa, P.; Richter, R.; Hlavinka, Petr; Trnka, Miroslav
2015 - anglický
Especially in arid regions, drought stress is considered as one of the main reasons for yield reduction of plant. Zinc, as one of the essential microelements in crop plant, plays a crucial role in resistance to drought stress. The objective of the vegetation experiment established in 2011-2015 on locality Zaboice was to explore the effect of the foliar zinc application on the yield of poppy in interactions with weather conditions observed years. Effect of zinc foliar application was significantly dependent on the average daily air temperature (r =-0.936). Foliar application of zinc increases production of poppy seed, in the range from 6.9 to 25.5 % and the efficiency of zinc foliar fertilization increases with a widening deficit rainfall calculated as the difference between the precipitation sum and reference evapotranspiration of poppy growing season (r =-0.9072). In general, the results of the present study indicate that usage of zinc foliar application reduces the harmful effects of water deficit stress and increases resistance to drought stress in poppy plant.
Klíčová slova:
grain-yield; boron; cultivars; nutrition; manganese; wheat; soil; poppy; foliar nutrition; zinc; yield; drought; precipitation; evapotranspiration
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Foliar application of zinc reduces the risk of drought stress on poppy (Papaver somniferum L.)
Especially in arid regions, drought stress is considered as one of the main reasons for yield reduction of plant. Zinc, as one of the essential microelements in crop plant, plays a crucial role in ...
Orchids of Nepal: phytogeography and economic importance
Timsina, Binu; Rokaya, Maan Bahadur; Kindlmann, Pavel; Munzbergová, Z.
2015 - anglický
In total, 118 orchid species (25%) are endemic to the Himalayan region and 21 species are endemic to Nepal. Krober’s percentage similarity showed that the EAFR and ICFR have the highest percentage similarity (87%) followed by the MFR and ICFR (62%). In total, 92 species were used for medicinal purposes and 6 as food plants in Nepal. We conclude that Nepal is rich in orchid flora and the highest percentage of orchids originates from the EAFR.
Klíčová slova:
orchids; Nepal; economic importance
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Orchids of Nepal: phytogeography and economic importance
In total, 118 orchid species (25%) are endemic to the Himalayan region and 21 species are endemic to Nepal. Krober’s percentage similarity showed that the EAFR and ICFR have the highest percentage ...
LINCOLN – an algorithm for filtering daily NDVI MODIS data and deriving the start of the season
Bohovič, R.; Hlavinka, Petr; Semerádová, Daniela; Bálek, L.; Tadesse, T.; Hayes, M.; Wardlow, B.; Trnka, Miroslav
2015 - anglický
Monitoring drought has become an important tool for farmers and agriculture decision makers. This has increased efforts to create a monitoring system using satellite data that could provide an independent and current source of real information on vegetation condition. The aim of this study was to develop an algorithm for processing Normalized Difference Vegetation Index (NDVI) data from the Moderate Resolution Imaging Spectroradiometer. A software utility called LINCOLN was developed for this purpose. Its filtering output was further processed to yield a start of the season (SOS) metric. Different settings of the utility were tested and correlated to such phenological ground observations as the emergence of spring barley and the beginning of leaf sheath elongation in winter wheat. There was higher correlation observed in the case of winter wheat, probably due to its weaker dependence on crop sowing date. The matrix of coefficients of determination was applied to determine the optimal settings for the LINCOLN filter. The optimal absolute threshold NDVI value for SOS was set to 4,500.
Klíčová slova:
monitoring system; LINCOLN software; vegetation conditions
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
LINCOLN – an algorithm for filtering daily NDVI MODIS data and deriving the start of the season
Monitoring drought has become an important tool for farmers and agriculture decision makers. This has increased efforts to create a monitoring system using satellite data that could provide an ...
Convergence of morphological, biochemical, and physiological traits of upper and lower canopy of European beech leaves and Norway spruce needles within altitudinal gradients
Rajsnerová, Petra; Klem, Karel; Večeřová, Kristýna; Veselá, Barbora; Surá, Kateřina; Rajsner, Lukáš; Holub, Petr; Urban, Otmar
2015 - anglický
Climatic variation along altitudinal gradients provides an excellent natural experimental set-up for investigating the possible impacts of climate change on terrestrial organisms and ecosystems. The present work has explored for the first time the acclimation of upper versus lower canopy leaves or needles in European beech (Fagus sylvatica) and Norway spruce (Picea abies) forests along an altitudinal gradient. We tested the hypothesis that restrictive climatic conditions associated with high altitudes reduce within-canopy variations of leaf traits. The investigated beech and spruce forests were located on the southern slope of the Hrubý Jeseník Mountains (Czech Republic). All measurements were taken on leaves from the upper and lower parts of the canopy of mature trees (>60 years old) growing at low (400 m a.s.l.), middle (720 m a.s.l.), and high (1,100 m a.s.l.) altitudes. Generally, we observed that with increasing altitude, which is associated with adverse microclimatic conditions, a convergence of CO2 assimilation rate and other physiological, morphological, and biochemical characteristics between the upper and lower canopy occurred. However, differences in altitudinal response among individual traits and species were found. Such plasticity in acclimation of leaves and needles has the potential to cause substantial change in the photosynthesis of individual parts of forest canopies within the vertical profile and their contribution to the overall carbon balance of vegetation.
Klíčová slova:
lower canopy; Norway spruce; altitudinal gradients
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Convergence of morphological, biochemical, and physiological traits of upper and lower canopy of European beech leaves and Norway spruce needles within altitudinal gradients
Climatic variation along altitudinal gradients provides an excellent natural experimental set-up for investigating the possible impacts of climate change on terrestrial organisms and ecosystems. The ...
Surface water temperature modelling to estimate Czech fishery productivity under climate change
Svobodová, Eva; Trnka, Miroslav; Kopp, R.; Mareš, J.; Spurný, P.; Pechar, L.; Beděrková, I.; Dubrovský, M.; Žalud, Zdeněk
2015 - anglický
Freshwater fish production is significantly correlated with water temperature, which is expected to increase under climate change and affect fish growth, productivity, and survival. This study deals with estimating the change in water temperature in productive ponds and its impact on fishery in the Czech Republic. The target fish species were common carp (Cyprinus carpio), maraena whitefish (Coregonus maraena), northern whitefish (Coregonus peled), and rainbow trout (Oncorhynchus mykiss). It was hypothesized that there would be an increasing risk of high water temperature stress for fish. Water temperature calculations based on 3-day means of air temperature were tested in several ponds in three major fish production areas. The verified model was applied to the climate change conditions determined by standardized scenarios derived from the five global circulation models MPEH5, CSMK3, IPCM4, GFCM21, and HADGEM. The results for changed climate indicated limitations for Czech fish farming in terms of prolonged periods with fish temperature stress as well as the increased number of stress periods and increased number of days within these periods. It is very likely that Czech fishery will have to change the fish species farmed in particular productive areas. In particular, higher altitudes are likely to become less suitable for the Salmonidae.
Klíčová slova:
water temperature; Czech fishery productivity; climate change
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Surface water temperature modelling to estimate Czech fishery productivity under climate change
Freshwater fish production is significantly correlated with water temperature, which is expected to increase under climate change and affect fish growth, productivity, and survival. This study deals ...
Diurnal changes of monoterpene fluxes in Norway spruce forest
Juráň, Stanislav; Fares, S.; Křůmal, Kamil; Večeřa, Zbyněk; Urban, Otmar
2015 - anglický
Biogenic volatile organic compounds (BVOCs) are important components of biosphere–atmosphere exchange. Their emissions depend on various meteorological parameters and stresses. Diurnal fluxes of different monoterpenes were studied within a Norway spruce (Picea abies) mountain forest to investigate their dependence on temperature and global radiation. Fluxes of monoterpenes, the most abundant BVOCs in spruce, were modelled using an inverse Lagrangian transport model, and representative diurnal variation trigged by both temperature and light was observed. This research enables future parametrization and quantification of various factors driving bidirectional fluxes.
Klíčová slova:
diurnal dynamics; Norway spruce
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Diurnal changes of monoterpene fluxes in Norway spruce forest
Biogenic volatile organic compounds (BVOCs) are important components of biosphere–atmosphere exchange. Their emissions depend on various meteorological parameters and stresses. Diurnal fluxes of ...
Comparative growth characterization of frequently used substrains of the model cyanobacterium Synechocystis sp. PCC 6803 under varying culture conditions
Zavřel, Tomáš; Očenášová, Petra; Sinětova, M. A.; Červený, Jan
2015 - anglický
Cyanobacteria have gained increased attention as ideal candidates for biotechnological applications due to their capacity to produce valuable molecules ranging from therapeutic proteins to biofuels. Their natural phenotypic plasticity in highly dynamic environments enables easy deployment of new biotechnologies as well as opening possibilities for genetic engineering. This contribution presents a new approach to fast and reliable characterization of cyanobacteria growth in a flat panel photobioreactor that enables examination of changing light, temperature, and nutrient availability. The utilization of semi-continuous automatic cultivation with real-time culture growth monitoring provides a strong experimental basis for both characterization and optimization of cyanobacteria cultures in photobioreactors. We first characterized the autotrophic growth of the substrain of Synechocystis sp. PCC 6803 denoted as GT-L. This strain is capable of efficient growth under a wide range of environmental conditions with doubling time as fast as 5 h under favorable conditions. However, differences among Synechocystis sp. PCC 6803 substrains have been identified on both the genotype and phenotype levels. We therefore aimed to utilize the experimental platform to characterize multiple commonly used Synechocystis sp. PCC 6803 substrains. This method will enable us to identify substrains capable of robust growth and high production yields as reliable biotechnological candidates.
Klíčová slova:
growth characterization; cyanobacterium Synechocystis; culture conditions
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Comparative growth characterization of frequently used substrains of the model cyanobacterium Synechocystis sp. PCC 6803 under varying culture conditions
Cyanobacteria have gained increased attention as ideal candidates for biotechnological applications due to their capacity to produce valuable molecules ranging from therapeutic proteins to biofuels. ...
A system for environmental monitoring of the Russian Vostochny spaceport
Mochalov, V. F.; Grigorieva, O.; Brovkina, Olga; Potrjasaev, S.
2015 - anglický
The main objective of this study is to obtain a comprehensive assessment of the environment on the Vostochny spaceport’s large territory using remote sensing data. Time series satellite and airborne data enabled us to analyze the landscape elements that were under active construction. A methodology for comprehensive environmental assessment was developed and applied to the study area. The methodology included ecological zoning of the territory based on the degree of anthropogenic intensity using original software. The results showed that (1) the level of anthropogenic load increased by 21% from 2013 to 2014, (2) the environmental stability index area decreased by 21%, and (3) the relative tension index of the territory’s environmental situation decreased by more than 25%.
Klíčová slova:
environmental monitoring; vostochny spaceport
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
A system for environmental monitoring of the Russian Vostochny spaceport
The main objective of this study is to obtain a comprehensive assessment of the environment on the Vostochny spaceport’s large territory using remote sensing data. Time series satellite and airborne ...
Attribution of European temperature variability during 1882–2010: A statistical perspective
Mikšovský, Jiří; Pišoft, P.
2015 - anglický
Gridded monthly temperature data (GISTEMP and Berkeley Earth) covering the European region were investigated for the presence of components attributable to climate forcings, both anthropogenic and natural, and to major modes of internal climate variability. Effects of individual predictors were separated by multiple linear regression applied to time series over 1882–2010. It was shown that the presence of a warming trend correlated with greenhouse gases concentration was generally strong in European temperatures and typically combined with mild cooling ascribable to anthropogenic aerosols. Components attributable to variations in solar activity were rather weak and not statistically significant in most locations, as were the imprints of large volcanic eruptions. A strong association between North Atlantic Oscillation phase and temperature was confirmed for much of Europe, while temperature oscillations synchronized with the El Niño Southern Oscillation were quite limited in magnitude and displayed low levels of statistical significance. The influence of the Atlantic Multidecadal Oscillation was noticeable particularly in the western-most parts of Europe, whereas the Pacific Decadal Oscillation’s significant impact extended to Scandinavia.
Klíčová slova:
european temperature; climatology
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Attribution of European temperature variability during 1882–2010: A statistical perspective
Gridded monthly temperature data (GISTEMP and Berkeley Earth) covering the European region were investigated for the presence of components attributable to climate forcings, both anthropogenic and ...
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