Open AccessCover crop effects on soil carbon dioxide emissions in a semiarid cropping system
Author(s) -
Nilahyane Abdelaziz,
Ghimire Rajan,
Thapa Vesh R.,
Sainju Upendra M.
Publication year - 2020
Publication title -
agrosystems, geosciences and environment
Language(s) - English
Resource type - Journals
ISSN - 2639-6696
DOI - 10.1002/agg2.20012
Subject(s) - canola , agronomy , cover crop , sativum , vicia villosa , hordeum vulgare , environmental science , crotalaria juncea , cambisol , raphanus , summer fallow , crop , soil water , green manure , biology , poaceae , cropping , ecology , soil science , agriculture
Cover crops improve soil health and environmental quality by enhancing soil organic carbon (SOC) sequestration and nutrient cycling in agroecosystems. This study evaluated the effect of cover crops on soil CO 2 –C emissions, temperature, and water content during cover crop growth from April to October, 2017 and 2018. Treatments included fallow, pea ( Pisum sativum L.), oat ( Avena sativa L.), canola ( Brassica napus L.), pea–oat (POmix), pea–canola (PCmix), pea–oat–canola (POCmix), and POC–hairy vetch ( Vicia villosa L.)–forage radish ( Raphanus sativus L.)–barley ( Hordeum vulgare L.) (six species mixture; SSmix). The CO 2 –C emissions were monitored weekly from April to October each year using a portable infrared‐gas analyzer. Seasonal changes in CO 2 –C emissions varied with cover crops and peaked as soil temperature and water content following precipitation events. Average CO 2 –C emissions across sampling dates was 46–70% greater under pea than under fallow, canola, and POmix in 2017, but not different among cover crops in 2018. Although the emissions were higher than fallow, canola and POmix plots had lower CO 2 –C emissions than other cover crops. Pea as sole cover crop or in mixtures (PCmix, POCmix, SSmix) increased CO 2 –C emissions and microbial activity whereas canola and POmix mixture reduced the emissions during the period with higher precipitation.