Die Bodenkultur - Journal for Land Management, Food and Environment
P. Hlavinka, J. Eitzinger, V. Smutny, S. Thaler, Z. Zhalud, P. Rischbeck und J. Kren:
The performance of CERES-Barley and CERES-Wheat under various soil conditions and tillage practices in Central Europe
Crop growth models are regarded as particularly useful tools for assessing plant production potentials, estimating the impact of climate change and analyzing the available adaptation options in agricultural crop production. Changes in management practices and tillage techniques that save water in the soil are among most frequently proposed adaptation measures in semi-arid areas. The main objective of the submitted study was to evaluate ability of two CERES (crop-environment resource synthesis) models (CERES-Barley and CERES-Wheat) to mimic the yields and soil water course under conventional (with ploughing) and minimum (without ploughing) tillage practices at two different locations (in the Czech Republic and Austria). Moreover, the behavior of the models under various management approaches (e.g., the fertilization level) and soil and climatic conditions within four sites in Central Europe was evaluated. Winter wheat and spring barley, the most important European cereal crops, were included. The yield level was successfully estimated (especially for soils without groundwater impact to the rooting zone) and the relative mean bias error (rMBE) varied from –19.6 % to 13.4 %. Consequently, the rMBE for the estimated seed weight varied from 5.4 % to 13.0 %, the time of flowering from 0.8 % to 3.0 % and the time of maturity from –3.3 % to 2.0 %. The soil water dynamics were also simulated and the rMBE varied from –28.5 % to 0.0 % and the relative root mean square error (rRMSE) varied from 9.0 % to 31.2 % in all of the experiments. The above ground biomass accumulation was estimated quite well with a simulation efficiency index from 0.92 to 0.83. On the basis of achieved results it could be concluded that tested models provided reasonable estimates of included parameters but they could be used for analysis of adaptation measures (such as tillage approach) only with certain caution. From the soil water measurements and simulations, it could be concluded that minimum tillage leads to an increase of the soil water on the Chernozem of Raasdorf. On the other side, ploughing seems to provide slightly larger soil water reserves on the fluvisol of Žabcˇice compared to the applied reduced soil cultivation (where potential long term effects are still not established), probably as a consequence of the higher soil compaction in minimum tillage on clay soil.
Key words: Minimum tillage, ploughing, climate change adaptation.