Miháliková M., Matula S., Doležal F. (2013) The database of soil hydrophysical properties in the Czech Republic called HYPRESCZ was created. It is based on the European database HYPRES, HYdraulic PRoperties of European Soils, and follows its structure with few modifications. It collects the available data from the Czech Republic from which pedotransfer functions (PTFs) for the estimation of soil hydrophysical properties from easily available soil properties can be derived and 2101 database entries were collected. The entries have different quality of data, out of the total number of entries 707 entries were applicable to PTFs derivation for the estimation of soil water retention curves (SWRCs). After elimination of replicates, finally 159 unique soil horizons (arable land only) were used for PTFs derivation. The parametric continuous pedotransfer functions for estimation of SWRCs in the Czech Republic were derived within this study and are based on Wösten's model. The retention curves were estimated using both these newly derived PTFs and Wösten's original model, which was derived for European soils in general. The uncertainty of estimation was evaluated, employing the root mean squared error (RMSE) and the coefficient of determination (R 2 ) comparing the PTF-estimated and the directly fitted retention curves. The reliability of the newly derived PTFs for Czech soils was higher (RMSE = 0.059 cm 3 /cm 3 and R 2 = 71%) compared to Wösten's general PTFs (RMSE = 0.11 cm 3 /cm 3 and R 2 = 36%).

The unsaturated hydraulic conductivity K(h) is a key soil parameter governing the water and solute transportation processes. The course of this function depends on the geometry of the pores which is determined by the soil's physical and chemical properties. Many studies focus on the comparison of soil hydraulic conductivity under different conditions. Despite the recent progress in this research field, no reference method for measuring the K(h) in situ exists. This study focuses on the effect of the initial water content of the soil as a factor influencing the measured K(h). The study was performed in situ over short time period and with several replications close to each other in order to reduce the effect of other factors which could cause variations. Two tension infiltrometers were used and compared: A Hood infiltrometer IL-2700 and a Minidisk infiltrometer. Three different levels of initial water content (dry, medium wet and wet) were applied for each of the two infiltrometers, and three pressure heads (-0.5; -1 and -3 cm) for each measurement. According to the results, the Minidisk infiltrometer showed significant sensitivity to the initial water content, while measurements performed using the Hood infiltrometer were more stable.

Hydraulic conductivity at and near saturation (Ks and K(h)) are among the most important characteristics defining water behavior in soil. Characterization of possibilities, advantages and limitations of the Mini Disk infiltrometer (MDI) for Ks and K(h) determination in comparison with Hood infiltrometer (HI) was the main aim of this study. The MDI device was subjected to testing on a cultivated silty clay loam soil under three different tillage treatments; conventional, reduced and no-tillage plot. The results are based on 72 infiltration experiments carried out during four experimental phases within one year. Steady-state and transient data analysis methods were applied. K(h) values were determined for van Genuchten hydraulic parameters taken from different sources (two versions of User’s manual, Rosetta). The results show suitability of MDI to determine K(h) of tested soil; clear differences have been observed between the K(h) values measured on plots with different tillage treatment. However, these values were significantly lower (ANOVA, α = 0.05) than those measured by HI. MDI based data were reflecting seasonal changes in structure and pore-size distribution with quantification of macropore contribution to the total saturated flux. Application of K(h) MDI data for fine-textured and structural soils evaluated before 2010 should be reconsidered.

Improvement of agricultural water management by implementing more efficient irrigation methods is essential for sustainable use of water and soil resources. The main objective was to assess and compare the use of parametric evaluation (PM) and multi‐criteria assessment (MCA) in the decision and planning process of irrigation management by land suitability assessment of three irrigation techniques. Land and soil properties were determined and assessed, and suitability maps were produced for surface, sprinkler and drip irrigation methods in the Çarşamba Delta plain (Black Sea region, Turkey; 972.2 ha). MCA was more flexible and sensitive due to the analytical hierarchy process and thus better reflected real conditions, than the widely used PM. In both approaches, drip irrigation was the most suitable. The main restricting factors in all irrigation systems in this area were slope, soil depth and soil texture. Results demonstrated that the arability of 33% (PM) or 30% (MCA) of the study area would be improved by employing drip irrigation instead of surface or sprinkler irrigation. Maps show where the change of traditional surface irrigation system should start. Such a change would be projected into better water use efficiency and more efficient use of soil while reducing degradation processes, namely soil erosion. © 2019 John Wiley & Sons, Ltd.

Lysimeters are basic instruments for evapotranspiration measurement. This study characterized the actual evapotranspiration of unirrigated and unfertilized grass in a warm region of the Czech Republic on a Chernozem loamy soil. An SFL-300 weighing lysimeter (diameter 0.3 m, depth 0.3 m) was used for this purpose. The suction at its bottom was maintained at the same level as in the native soil nearby. We selected 585 rainless days with regular records for the analysis of daily differences. On most days, the lysimeter-measured actual evapotranspiration, ET a , was smaller than the Penman-Monteith FAO 56 reference crop evapotranspiration, ET 0 . The FAO 56 procedure was found to be a reasonable estimator of the unstressed evapotranspiration in a moderately stressed environment. The ET a /ET 0 ratio and the canopy surface resistance, r s , depend on the soil water content and suction measured at 5 cm. These graphs break down into horizontal unstressed parts and declining (for ET a /ET 0 ) or inclining (for r s ) water-stressed parts. The ratio ET a /ET 0 is about 85% and r s is about 250 s m −1 when the grass is not under water stress. The annual curve of the unstressed crop coefficient has a sine shape. An energy balance criterion suggests that advection of heat is important in winter but not so much in summer. The study provides parameters of evapotranspiration for a canopy that can be found on many standard weather stations and demonstrates that high-quality research into evapotranspiration of low, dense, and shallow-rooting crops is possible with small lysimeters of this type.Abbreviations: ASCE, American Society of Civil Engineers; DOY, day of the year; ET, evapotranspiration; ET a , actual evapotranspiration; ET 0 , reference crop evapotranspiration; LYW, lysimeter weight (actually mass); SFL, smart field lysimeter; SWW, percolate collecting bottle mass.Evapotranspiration is a basic component of the natural water cycle and water balance. Its quantification is therefore of utmost importance for many branches of water management. The potential evapotranspiration, representing the climatic "demand" for water (Hillel, 1998;Irmak and Haman, 2003;Verstraeten et al., 2008) has long ago been recognized as a suitable benchmark to which other types of evaporation in nature can be related. The FAO 24 (Doorenbos and Pruitt 1977) and then the FAO 56 (Allen et al., 1998) and American Society of Civil Engineers (ASCE) (Jensen and Allen, 2016) methodologies offered a concept of the reference crop evapotranspiration, ET 0 , corresponding to the actual evapotranspiration of a standard, dense, and extensive herbal stand sufficiently supplied with soil water (and thus its potential evapotranspiration). The FAO 56 reference low crop is grass, assumed to be 0.12 m high, having a shortwave albedo of 0.23 and surface resistance of 70 s m −1 . Up to now, one of the widely used way of estimating ET 0 has been the one based on the Penman combination concept resulting in the PenmanMonteith evaporation equation (cf. Allen et al., 1998; f...