Effect of moisture content, temperature and nitrogen fertilization on carbon dioxide evolution from field soils

• Published in: Soil biology & biochemistry 1978, Vol.10 (5), p.417-423
• Main Authors: Kowalenko, C.G., Ivarson, K.C., cameron, D.R.
• Format: Article
• Language: English
• ISSN: 0038-0717; 1879-3428
• DOI: 10.1016/0038-0717(78)90068-8

The evolution of CO 2 from field plots was measured for 3 yr, on two soil types, with and without N fertilization and relationships with average air temperature, average soil water content and an interaction term were derived. Multiple correlation coefficients ranged between 0.64 and 0.85 and average air temperature accounted for most of the variance in the relationships. Negative correlation coefficients with average soil water content predominated particularly in the fall when rainfall was high and evaporation was low. Regression equations relating the three factors were homogeneous within but not between soils. N consistently reduced the CO 2 evolved from the soils despite the effect of the year, soil type or rate of application. The reduced microbial activity due to N fertilization observed in the field was confirmed with laboratory incubations using Warburg techniques. Laboratory experiments showed that the lowering of soil pH by N addition was largely, but not entirely responsible for the decreased activity.