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Crop yield estimation in the field level using vegetation indicies
Jurečka, František; Hlavinka, Petr; Lukas, Vojtěch; Trnka, Miroslav; Žalud, Zdeněk
2016 - English
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.
Keywords:
Yield; drone; spring barley; NDVI; EV12
Fulltext is available at external website.
Crop yield estimation in the field level using vegetation indicies
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 ...
Physiological equivalent temperature as an indicator of the UHI effect with the city of Prague as an example
Zahradníček, Pavel; Žák, M.; Skalák, Petr
2016 - English
Description of an Urban Heat Island (UHI) using the difference in air temperature is one of the world's most studied characteristics. If, however, one wants to express how the temperature is perceived by humans, one must consider the overall effect of air temperature, wind speed, air humidity and radiation flows, which is expressed using temperature bioclimatological indexes. One of them is the socalled physiological equivalent temperature (PET), which is used for quantification of the overall effect of meteorological parameters combined with human energetic balance and which is perceived by humans. The RayMan (MATZARAKIS et al. 2007, 2010) microscale models in the city of Prague were used to simulate biometeorological conditions describing the effect on humans using PET.
Keywords:
model; physiological equivalent temperature; uhi; RayMan; Prague
Available at various institutes of the ASCR
Physiological equivalent temperature as an indicator of the UHI effect with the city of Prague as an example
Description of an Urban Heat Island (UHI) using the difference in air temperature is one of the world's most studied characteristics. If, however, one wants to express how the temperature is perceived ...
Effect of high temperature and water shortage stresses duration during anthesis on the selected winter wheat yield formation components
Hlaváčová, Marcela; Rapantová, Barbora; Surá, Kateřina; Klem, Karel; Hlavinka, Petr; Trnka, Miroslav
2016 - English
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.
Keywords:
growth chamber; harvest index (HI); spike productivity; Tobak; winter wheat
Fulltext is available at external website.
Effect of high temperature and water shortage stresses duration during anthesis on the selected winter wheat yield formation components
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 ...
WINTER RECREATION AND SNOW
Zahradníček, Pavel; Rožnovský, J.; Štěpánek, Petr; Farda, Aleš; Brzezina, J.
2016 - English
Climate assessment should not be limited to just statistical analysis, but also look at relationships in data and its uses in other areas of everyday life. One such area is tourism and recreation, which is also to a great extent influenced by the weather. This paper focuses on the winter season and the related possibilities for tourism. One of the key factors is snow conditions of the particular place. This analysis takes into account the amount of new snow and maximum snow depth and changes in these parameters as a result of the current global climate change. Especially in the last 15 years, years with less snow are more frequent and this is especially seen at highest altitudes of the country. The study also analyzed outputs of climate models with regards to winter season, including calculations of the number of melting days.
Keywords:
new snow; total snow depth; climate change; climate models
Available at various institutes of the ASCR
WINTER RECREATION AND SNOW
Climate assessment should not be limited to just statistical analysis, but also look at relationships in data and its uses in other areas of everyday life. One such area is tourism and recreation, ...
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
2016 - English
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.
Keywords:
grains number; growth chamber; thousand grain weight (TGW); water shortage; winter wheat
Fulltext is available at external website.
Effect of drought stress on selected winter wheat yield formation components within pot and field experiimental design
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 ...
Application of DSSAT model to simulated thermophilic crops in central and southern Europe
Potop, V.; Mateescu, C.D.; Türkott, L.; Zahradníček, Pavel; Boroneant, C.; Constantinescu, F.; Iamandei, M.
2016 - English
This study presents applications of DSSAT version 4.5 software package to simulate thermophilic crops. The results are used to identified adaptation options to reduce impacts of climate changes, pest and diseases in thermophilic crops in the central and southeastern Europe, specifically in Elbe River lowland and Romania. For the Czech Republic, experimental research at farm level includes: (1) testing thermophilic assortment of vegetables in Elbe lowland conditions; (2) monitoring the meteorological data, phenological phases, soil characteristics, leaf area and the amount of aboveground biomass on farmer vegetable fields. For Romania, the focus is put on crop water use efficiency under current and future climate scenarios for thermophilic species (maize) in different agricultural sites from south and south-eastern regions. CERES Maize and CROPGRO-vegetables modules embedded in DSSAT were used.
Keywords:
CERES Maize; CROPGRO-tomato; plant protection; climate change
Available at various institutes of the ASCR
Application of DSSAT model to simulated thermophilic crops in central and southern Europe
This study presents applications of DSSAT version 4.5 software package to simulate thermophilic crops. The results are used to identified adaptation options to reduce impacts of climate changes, pest ...
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
2016 - English
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.
Keywords:
vegetation; modis; products; drought monitor; remote sensing; modis; ndvi; seasonal greenness
Available at various institutes of the ASCR
Detection of drought events using combination of satellite data and soil moisture modelling
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 ...
Comparison of drought effect on young coppiced and standard individuals of sessile oak
Stojanović, Marko; Čater, M.; Pokorný, Radek
2016 - English
Assimilation and photosynthetic efficiency (quantum yield) of young oaks were compared in coppice and standard sessile oak stands of comparable age (100-120 years) under different light intensity categories. Measurements of assimilation response were performed during three consecutive growing seasons (2012, 2013 and 2014). In every category 8 young oaks of generative origin and same number of coppice sprouts of different stool were measured. The quantum yield in optimal conditions in standards was highest in the category A of closed canopy, while in coppices in category C. During severe drought in 2013 the drop in efficiency of standards was evident in all categories, while in coppices no differences in efficiency were confirmed between optimal and drought stress, proving the advantage of young coppices over standards.
Keywords:
coppice; standards; photosynthetic response; quantum yield; light conditions; drought response
Available at various institutes of the ASCR
Comparison of drought effect on young coppiced and standard individuals of sessile oak
Assimilation and photosynthetic efficiency (quantum yield) of young oaks were compared in coppice and standard sessile oak stands of comparable age (100-120 years) under different light intensity ...
Potential of the sentinel-2 red edge spectral bands for estimation of eco-physiological plant parameters
Malenovský, Zbyněk; Homolová, Lucie; Janoutová, Růžena; Landier, L.; Gastelluetchegorry, J-P.; Bertholt, B.; Huck, A.
2016 - English
In this study we investigated importance of the spaceborne instrument Sentinel-2 red edge spectral bands and reconstructed red edge position (REP) for retrieval of the three eco-physiological plant parameters, leaf and canopy chlorophyll content and leaf area index (LAI), in case of maize agricultural fields and beech and spruce forest stands. Sentinel-2 spectral bands and REP of the investigated vegetation canopies were simulated in the Discrete Anisotropic Radiative Transfer (DART) model. Their potential for estimation of the plant parameters was assessed through training support vector regressions (SVR) and examining their P-vector matrices indicatingsignificance of each input. The trained SVR were then applied on Sentinel-2 simulated images and the acquired\nestimates were cross-compared with results from high spatial resolution airborne retrievals. Results showed that contribution of REP was significant for canopy chlorophyll content, but less significant for leaf chlorophyll content and insignificant for leaf area index estimations. However, the red edge spectral bands contributed strongly to the retrievals of all parameters, especially canopy and leaf chlorophyll content. Application of SVR on Sentinel-2 simulated images demonstrated, in general, an overestimation of leaf chlorophyll content and an underestimation of LAI when compared to the reciprocal airborne estimates. In the follow-up investigation, we will apply the trained SVR algorithms on real Sentinel-2 multispectral images acquired during vegetation seasons 2015 and 2016.
Keywords:
canopy chlorophyll; image acquisition; physiological models; high spatial resolution; vegetation cabioy; agricultural fields; leaf chlorophyll content; multispectral images; space-borne instruments; support vector regression (SVR); vegetation canopy
Available at various institutes of the ASCR
Potential of the sentinel-2 red edge spectral bands for estimation of eco-physiological plant parameters
In this study we investigated importance of the spaceborne instrument Sentinel-2 red edge spectral bands and reconstructed red edge position (REP) for retrieval of the three eco-physiological plant ...
The usage of algae in biogas transformation
Paroulkova, P.; Sukačová, Kateřina; Murgasová, K.; Vítěz, T.; Chovanec, J.
2016 - English
Using of algae in a biogas transformation is still in the beginning. However, the microalgae have large potential from the perspective of growing demands on biogas quality and trend of using,natural resources. First of all, it is their ability to fix carbon dioxide (CO2) using photosynthesis and presumed ability of some algae to metabolize hydrogen sulphide (H2S). Biogas contains not only required methane but also components causing its worse quality such as mentioned CO2 and H2S. Therefore, the algae are potential biological systems for biogas-conditioning. The microalga Chlorella pyrenoidosa Chick (IPPAS C2) was used for fixation of CO2 and H2S in our experiment. The microalgae were cultivated in a medium BG 11. The algal suspension was aerated with the biogas during two weeks. Different values of CO2 concentration measured in the input and output confirmed decrease of CO2 caused by intensive growth of algal culture. Decline of H2S was not confirmed.
Keywords:
biogas purification; carbon dioxide; methane; hydrogen sulphide; biological treatment
Available at various institutes of the ASCR
The usage of algae in biogas transformation
Using of algae in a biogas transformation is still in the beginning. However, the microalgae have large potential from the perspective of growing demands on biogas quality and trend of using,natural ...
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