|Pikul Jr, Joseph|
Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: October 22, 1998
Publication Date: N/A
Technical Abstract: Concern for soil quality and related environmental issues requires new knowledge to minimize agriculture's impact on the environment. Less intensive strip tillage may reduce the impact of row-crop agriculture on labile soil carbon and carbon dioxide loss. Objectives were to quantify short-term tillage-induced CO2 loss relative to tillage intensity and penetrometer resistance profiles after different strip tillage tools compared to moldboard plow. Various strip tillage tools, spaced at 76 cm, were used and gas exchange measured with a large portable chamber. Gas exchange was measured regularly for six hours and then at 24 and 48 hours. An index of "soil looseness" was calculated from cone index data measured with a recording penetrometer. Seasonal trends were observed in the cumulative CO2 loss. No-till had the lowest CO2 flux and moldboard plow had the highest immediately after tillage that declined as the soil dried. Other forms of strip tillage had an initial flush related to tillage intensity that was intermediate between these extremes, with both the 5- and 24-hour cumulative losses related to soil volume disturbed by the tillage tool. The looseness index was highest on moldboard plow and subsoil and least with no-till and was linearly related to cumulative CO2 loss. Reducing the volume of soil disturbed by tillage should enhance soil and air quality by increasing labile soil carbon content. These results suggest soil and environmental benefits of strip tillage be considered in soil management decisions.