High frequency monitoring of carbon (iv) oxide evolution from a tropical soil amended with organomineral fertilizer in a screenhouse Ile-Ife, Nigeria

The study compared responses of carbon (iv) oxide evolved from an Ultisol sampled at different time scales and the soil properties when amended with organomineral fertilizer (OMF); thus tracking the carbon footprint of the amendment in ambient air. The carbon (iv) oxide efflux was measured titrimetrically in a static chamber set up in a screenhouse at sub-daily, daily and weekly time scales. At the same time, the antecedent soil properties were determined using standard methods. The treatments involved OMF addition at three rates (0 kg OMF, 40 kg Urea-N + 2.5 tons/ha organic fertilizer and 40 kg Urea-N + 5 tons/ha organic fertilizer) based on some Nigerian indigenous vegetable nutrient requirements. The result showed that a more detailed and accurate understanding of CO2 evolution processes was revealed at daily sampling resolution while sub-daily variation occurred in response to sub-daily variation in ambient temperature. Organomineral fertilizer at 40 kg/ha Urea + 2.5 tons/ha OF rate was comparatively safer in C management through the reduction in the CO2 released thus constituting a better alternative in terms of the greenhouse effect. Thus, the study recommends at least daily monitoring for a detailed understanding of CO2 evolution dynamics and management and identifies OMF rate with less CO2 release as a comparatively better alternative in the production of those vegetables in the environmental context.