Impact of various drought patterns on simulated crop growth and yield in a semi-arid agricultural region in central Europe

摘要

Shortage of water is an important, and in some cases, the chief cause of variation in wheat yields in many parts of the world. Also, the impact of frost, heat, drought, diseases, insects and weeds can be predicted more accurately with a clear pictureof the relationships between growth stage and plant response to stress. The impacts of climate variabilities and change on crop production and water balance have been studied with the use of crop models by many workers (Eitzinger et al, 2000; Semenov andPorter, 1995; Bacsi and Hunkar, 1994; Mearns et al., 1992). The hydrological cycle will be affected through a change in precipitation, evapotranspiration, the magnitude and timing of runoff, as well as through a possible change in intensity and frequency of floods and droughts (Watson et al, 1996). Increased CO_2 concentrations can affect plant growth directly through stimulation of photosynthesis and reduction of transpiration and, as a result, can improve water use efficiency (WUE) (Rosenberg et al.,1990). Crop simulation models for a variety of crops and applications, including soil water balance assessment, have been described (e.g. Majercak et al., 1994; Robinson et al., 1992; Wilhite, 1993). The aim of the study was to highlight the critical water balance parameters and water stress situations for the selected cultivars under the present climatic conditions (1 x CO_2 weather) and modified (2 * CO_2) climate scenarios (combined effect).