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Application of growth models for local assessment of the impact of climate change on selected crops
Hlavinka, Petr ; Trnka, Miroslav ; Balek, Jan ; Dubrovský, Martin ; Pohanková, Eva ; Žalud, Zdeněk
This publication is focused on the description of specialized software named as crop growth models and its using emphasizing the application for climate change impact assessment at local scale. The ambition of this publication is to introduce brief history of the crop growth models development, its classification, actual trends of their progress and applications and last but not least, present procedure leading to the preparation of the input datasets, the initial setup, parameters calibration, validation through set of independent datasets and consequently the implementation of climate change scenarios for assessment of possible impact of future conditions on selected important field crops and set of representative sites in the Czech Republic.
Fulltext: content.csg -  PDF
Plný tet: Metodika_rustove_modely_2015 - PDF
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Remotely sensed NDVI as a support tool for agricultural drouhgt assessment
Hlavinka, Petr ; Semerádová, Daniela ; Trnka, Miroslav ; Lukas, V. ; Bohovic, R. ; Balek, J. ; Wardlow, B. ; Hayes, M. ; Tseagaye, T. ; Žalud, Zdeněk
Th e main aim of the submitted study was to introduce how the remotely sensed NDVI (Normalized Diff erence Vegetation Index) could be used for agricultural drought assessment within the Czech Republic. Th e relationship between NDVI values and observed yields of spring barley and winter wheat was analyzed for selected districts. Moreover the ability of NDVI (at district level in the form of seasonal greenness – SG) to explain the water balance or drought occurrence and severity was tested. For this purpose a data mining technique was used. A relative form of the Palmer Drought Severity Index (rPDSI) was used as a dependent variable to indicate drought occurrence. A Standardized Precipitation Index (SPI), percentage of average SG (PASG), Start of Season Anomaly (SOSA) and district identifi cation were used as independent variables. MODIS (Moderate Resolution Imaging Spectroradiometer) observations from the Terra satellite were used as a source of NDVI. Th e situation within 6 selected districts (Olomouc, Přerov, Znojmo, Břeclav, Žďár nad Sázavou and Havlíčkův Brod) during the period from 2000 to 2012 was analyzed. Promising results were achieved, so practical use of this approach (e.g. for spatial and temporal assessment of drought stress within the vegetation) could be expected.
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Calibration of the selected crop growth models for spring barely
Pohanková, E. ; Trnka, Miroslav ; Hlavinka, Petr ; Takáč, J. ; Kersebaum, Ch. ; Orság, Matěj ; Fischer, Milan ; Pokorný, E. ; Žalud, Zdeněk
The climate change is one of the most discussed global problems. One option how to estimate the effects of expected future climate conditions on plant production is the use of the crop growth models. Our aim was the calibration of two models (Daisy and Hermes) based on observed and measured data that were collected for spring barley (represented by cultivars Tolar and Blaník) at experimental site Bystřice nad Pernštejnem during 2011 and 2012. The onset of flowering was underestimated by an average of 1.1 and 1.6 days and maturity by 5.8 and 9.0 days using Daisy and Hermes respectively. On average Daisy systematically underestimated yields by 0.3 t/ha-1 and Hermes overestimated yields by 1.24 t/ha-1. We expect further improvement of these models estimates using the available result from the following years
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Using remotely sensed NDVI for drought impact assessment within selected crops
Hlavinka, Petr ; Trnka, Miroslav ; Semerádová, Daniela ; Dobrovolný, P. ; Balek, J. ; Možný, M. ; Štěpánek, P. ; Hayes, M. ; Svoboda, M. ; Wardlow, B. ; Žalud, Zdeněk
The relationship between Normalized Difference Vegetation Index (NDVI) and selected agrometeorological parameters (yields of selected crops, water balance) was investigated. The source for NDVI was Spectroradiometer MODIS within satellite Terra and it was available for grids in resolution 500 x 500 m from 2000 to 2010. The analysis was conducted within 12 grids spread through Southern and Central Moravian region. The information about cultivated crops (including spring barley, winter wheat, maize for grains, sugar beet and winter rape) were collected from the farmers and water balance simulated using SoilClim model.
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Water balance in short rotation poplar coppice and reference grass-plot in conditions of Czech-Moravian Highlands
Orság, Matěj ; Fischer, Milan ; Trnka, Miroslav ; Hlavinka, Petr ; Kučera, J. ; Balek, J. ; Žalud, Zdeněk
This text presents results of a study focusing on differences of water balance between two contrasting cultures - short rotation poplar coppice and grass plot in conditions of Czech-Moravian Highlands. Actual evapotranspiration (by Bowen ratio energy balance method), precipitation and soil moisture in two layers (0 – 0.45 m and 0.45 – 0.90 m) were measured on both plots during seasons 2008 – 2010. The seasonal water lost through evapotranspiration was higher for the grass (560.4 and 508 mm for grass and 523.8 and 351.8 mm for poplar during growing season 2009 and 2010 respectively), but generally the observed amounts of ETa are comparable for both cultures and within the range of values described in literature. Results of soil moisture measurements expressed as soil water availability [mm] were compared with simulations obtained from water balance model SoilClim. The model a little bit underestimated the amount of available water in the system, since based on water balance closure we suggest that there is a higher water income than was recorded from precipitation. This extra water found in observed systems may be supplied probably by lateral underground water inflow from the upper fields.
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