Influence of Reduced Tillage, Fertilizer Placement, and Soil Afforestation on CO2 Emission from Arable Sandy Soils

Abstract

Extreme meteorological phenomena resulting from climate change caused by anthropogenic emissions of greenhouse gases (GHG) require the implementation of CO2 mitigation practices from various industries, including agriculture. Owing to varying soil, climatic, and agrotechnical characteristics, they may have different efficiencies in mitigating soil CO2 emissions. The aim of this study was to evaluate the impact of three mitigation practices (reduced tillage, deep fertilizer placement, and soil afforestation) on CO2 emissions from sandy soils in Central and Eastern Europe allowing the prediction of the mitigation effectiveness of these methods. The average soil CO2-C flux under a moldboard plow system ranged from 218.4 ± 108.4 to 263.7 ± 176.6 mg CO2-C m−2 h−1 and under a reduced tillage system ranged from 169.7 ± 118.7 to 163.6 ± 115.2 mg CO2-C m−2 h−1 in a year with normal meteorological conditions and under extreme drought conditions, respectively. In the dry growing season, similar amounts of CO2-C were released from the soil fertilized to the soil surface and after mineral fertilizers application at a depth of 10 cm and 20 cm (133.7 ± 155.8, 132.0 ± 147.5 and 131.0 ± 148.1 mg CO2-C m−2 h−1, respectively). Meanwhile, from the forest soil, the average CO2-C emission in the dry growing season was 123.3 ± 79 mg CO2-C m−2 h−1. The obtained results revealed that reduced tillage on sandy soil allowed for reduced CO2 emissions from the soil by 28.7–61.2% in normal and drought weather, respectively. Under drought conditions, deep fertilizer placement did not reduce CO2 emissions from sandy soil, and CO2 emissions from forest soils were even higher than from arable soils.