The course, stratification and possibility of simulating relative air humidity in winter wheat stand

  • Jana KRČMÁŘOVÁ Department of Crop Science, Breeding and Plant Medicine, Mendel University in Brno
  • Radovan POKORNÝ Department of Crop Science, Breeding and Plant Medicine, Mendel University in Brno
  • Tomáš STŘEDA Department of Crop Science, Breeding and Plant Medicine, Mendel University in Brno
Keywords: microclimate, canopy, relative humidity, evapotranspiration, soil moisture, phenology

Abstract

The aim of this study was: (i) long-term (2010, 2011 and 2013) evaluation
of the relative air humidity in the winter wheat canopy, (ii) finding of relationships between
relative air humidity in canopy and computed or measured meteorological values
(precipitation totals, evapotranspiration, moisture balance, specific air humidity, volume
soil moisture, % of available soil water content, value of soil water potential), (iii) testing
of simulation of daily relative air humidity, based on selected meteorological values and
potential evapotranspiration (FAO Penman-Monteith method) and actual evapotranspiration,
(iv) testing of simulation of relative air humidity hourly values in the wheat canopy,
(v) evaluation of dependence between relative air humidity and leaf wetness. The measurement
was performed at the experimental field station of Mendel University in Žabčice
(South Moravia, the Czech Republic). Data recording for wheat canopy was conducted by
means of a meteostation equipped with digital air humidity and air temperature sensors
positioned in the ground, effective height of the stand and in 2 m above the ground. The
main vegetation period of wheat was divided into three stages to evaluate differences in
various growing phases of wheat. The data from nearby standard climatological stations
and from agrometeorological station in Žabčice were used for establishment of relationships
between relative air humidity in winter wheat canopy and surrounding environment
by correlation and regression analysis. Relative air humidity above 90% occurred substantially
longer on the ground and at the effective height of the stand in comparison with
the height of 2 m. By means of regression analysis we determined that the limit of 90%
was reached in the canopy when at the climatological station it was just 60 to 90% for
ground level and 70 to 90% for effective height, especially during the night. 

Author Biographies

Jana KRČMÁŘOVÁ, Department of Crop Science, Breeding and Plant Medicine, Mendel University in Brno

Zemědělská 1, 613 00 Brno, Czech Republic

Radovan POKORNÝ, Department of Crop Science, Breeding and Plant Medicine, Mendel University in Brno

Zemědělská 1, 613 00 Brno, Czech Republic

Tomáš STŘEDA, Department of Crop Science, Breeding and Plant Medicine, Mendel University in Brno

Zemědělská 1, 613 00 Brno, Czech Republic

Published
2016-06-30
How to Cite
KRČMÁŘOVÁ, J., POKORNÝ, R., & STŘEDA, T. (2016). The course, stratification and possibility of simulating relative air humidity in winter wheat stand. Contributions to Geophysics and Geodesy, 46(2), 137-154. https://doi.org/10.1515/congeo-2016-0010
Section
original research papers