Atmung eines Bodens im Gemüsebau zu Beginn der Vegetationsperiode

Respiration of a soil used for vegetable crops at the beginning of the vegetation period Soil respiration was measured with a new portable soil respiration system (PP Systems, Hitchin, England) in vegetable plots in the greenhouse and field near Bonn from January to May 1996 with the following results:

• 1 The equipment proved suitable for the purpose over a wide range of temperatures.
• 2 Soil respiration ranged from less than 26 mg CO₂ in winter, 30–180 mg CO₂ in spring to 700 mg CO₂ m^?2 h^?1 in summer with large variations.
• 3 The largest soil respiration was recorded from peat-based commercial potting compost with small variations between measurements.
• 4 The Q₁₀ was 2,5 (±0,6) in the field for temperatures between 5–25°C.
• 5 The rate of soil respiration was affected by soil cultivation with the effect declining with temperature: Ploughing, which unveiled cold and produced a coarse soil surface, reduced soil respiration, whereas soil respiration was increased by fine soil cultivation.
• 6 In vegetable plots, soil respired 6–12 kg in cold (4°C), 40–50 kg CO₂ in cool (14°C) conditions in April and 170–210 kg CO₂/ha and 24 hours in warm (27°C) weather.