Aim of the DFG-project "Influence on global climate changes (Temperature and rainfall) on soil microorganisms and carbon turnover of cultivated farm soil" is to put into terms the carbon turnover of farm soil of a future climate with abundance, activity and diversity of soil microorganisms.
 
Within this project the main focus is on the interaction of increased temperature and modified rainfall regimes as well as their effects of back-coupling on the climate itself.
 
 
 
 
 
 
 
 
Therefore, temperature and rainfall were manipulated within a field experiment. The experiment consists of altogether 16 plots (4m²), half of it roofed during summertime and half of it serving to control the effects on the microclimatic conditions due to the roofs.
 
The manipulation of temperature will be carried out by overground heating wires and is navigated via UMS data logger (DT85) and temperature sensors (TH2-fs). The control (adjustment) will be ensured by a comparison of the soil temperature on heated and unheated area every minute.
 
Target value is a temperature difference of 2,5 °C in 4cm depth. Those 8 roofed plots are again divided into 4 subplots each, on which the following 4 treatments are established during the summer months:
 
a) present rainfall
b) reduction of rainfall amount
c) reduction of rainfall frequency
d) reduction of rainfall amount and frequency

During winter the rainfall amount will be increased on those plots with a rainfall reduction in the summer. Since establishment of the experiment in summer 2008 the carbon mineralisation, microbic activity of the soil as well as the carbon flow from litter into the soil are examined. Beside the carbon circulation the circular flow of nitrogen is another main focus of the studies.