Publikálás helye:
Agrokémia és Talajtan, 58: 215-226
Rövid összefoglaló:
Three soil tillage systems, representing three levels of soil disturbance, were tested
for their effect on CO2 emission from the soil. For these studies, large (10 cm high, 10
cm in diameter) undisturbed soil columns were incubated in a climate chamber, thus
combining the advantages of laboratory and field methods, as it was possible to record
the CO2 emission from soils with undisturbed structure under controlled temperature
and moisture conditions. A further aim was to optimise a newly elaborated measuring
technique, with special regard to the determination of optimum incubation time.
The data were evaluated and the timing of sample taking was optimised accordingly.
No statistical difference was found between the emission values measured after 3 and 6
hours of incubation, so the time was set to 3 hours.
A comparison of the emission values recorded for samples originating from the three
soil tillage methods [ploughing (SZ), direct drilling (DV), disking combined with deep
loosening (L+T)] indicated that the highest CO2 emissions arose from the direct drilling
treatment and the lowest from the ploughing treatment. This could be attributed to the
higher available organic C content in the less disturbed treatment.
In the soil moisture content range tested, CO2 emissions were found to rise with an
increase in soil moisture content at the beginning of the experiment, but in the fourth
week a decrease was observed in the value of CO2 emission at soil moisture contents
around the field water capacity. In all the treatments the emissions gradually declined as
the substrates were exhausted.
The results confirm that, due to the rapidity and complexity of processes taking
place in the soil, it is necessary and important for mutually complementary field and
laboratory measurements to be evaluated together.
