MANAGEMENT DECISIONS ON FARM-LEVEL AND THEIR LINK TO WEATHER REQUIREMENTS: A CASE STUDY FOR THE UPPER DANUBE RIVER BASIN

It is undeniable that the global warming has already affected the Earth’s biota, whereby the rise of air temperature is an important factor. Agricultural systems are also affected by climate change via the interrelated biophysical layers. Climate influences farmers` decisions in crop management. To simulate the interactions between climate/weather and the different crop management activities an agent based modelling approach is used, in which farmers` decision making is based on crop requirements from literature. To validate these decision algorithms on how farmers arrange their daily crop management decisions like planting, fertilizing, and harvesting due to changes of climate parameters, a statistical analysis of empirical data (1970-2003) on temperature and different crop growth stages, which represent different management activities, was carried out. Results show that every crop has to be considered separately and the requirements of the different crops on temperature have to be observed in different ways. There are crops which have a low germination temperature, for those the average daily temperature shows no relation with the planting day. In this case the temperature sum in a specific period is more precise. On the opposite side crops with a high germination temperature show significant correlation results with the average daily temperature of a period before the planting day.