Assessing climate change impacts on greenhouse gas emissions, N losses in drainage and crop production in a subsurface drained field

Qianjing Jiang; Zhiming Qi; Lulin Xue; Melissa Bukovsky; Chandra A Madramootoo; Ward Smith

doi:10.1016/j.scitotenv.2019.135969

Assessing climate change impacts on greenhouse gas emissions, N losses in drainage and crop production in a subsurface drained field

Sci Total Environ. 2020 Feb 25:705:135969. doi: 10.1016/j.scitotenv.2019.135969. Epub 2019 Dec 7.

Authors

Qianjing Jiang¹, Zhiming Qi², Lulin Xue³, Melissa Bukovsky³, Chandra A Madramootoo¹, Ward Smith⁴

Affiliations

¹ Department of Bioresource Engineering, McGill University, Sainte-Anne-de-Bellevue, QC H9X 3V9, Canada.
² Department of Bioresource Engineering, McGill University, Sainte-Anne-de-Bellevue, QC H9X 3V9, Canada. Electronic address: zhiming.qi@mcgill.ca.
³ National Center for Atmospheric Research, Boulder, CO 80307, USA.
⁴ Ottawa Research and Development Centre, Agriculture and Agri-Food Canada, Ottawa, ON K1A 0C6, Canada.

PMID: 31838422
DOI: 10.1016/j.scitotenv.2019.135969

Abstract

Future climate change-driven alterations in precipitation patterns, increases in temperature, and rises in atmospheric carbon dioxide concentration ([CO₂]_atm) are expected to alter agricultural productivity and environmental quality, while high latitude countries like Canada are likely to face more challenges from global climate change. However, potential climate change impact on GHG emissions from tile-drained fields is poorly documented. Accordingly, climate change impacts on GHG emissions, N losses to drainage and crop production in a subsurface-drained field in Southern Quebec, Canada were assessed using calibrated and validated RZWQM2 model. The RZWQM2 model was run for a historical period (1971-2000) and for a future period (2038 to 2070) using data generated from 11 different GCM-RCMs (global climate models coupled with regional climate models). Under the projected warmer and higher rainfall conditions mean drainage flow was predicted to increase by 17%, and the N losses through subsurface drains increase by 47%. Despite the negative effect of warming temperature on crop yield, soybean yield was predicted to increase by 31% due to increased photosynthesis rates and improved crop water use efficiency (WUE) under elevated [CO₂]_atm, while corn yield was reduced by 7% even with elevated [CO₂]_atm because of a shorter life cycle from seedling to maturity resulted from higher temperature. The N₂O emissions would be enhanced by 21% due to greater denitrification and mineralization, while CO₂ emissions would increase by 16% because of more crop biomass accumulation, higher crop residue decomposition, and greater soil microbial activities. Soil organic carbon storage was predicted to decrease 22% faster in the future, which would result in higher global warming potential in turn. This study demonstrates the potential of exacerbating GHG emissions and water quality problems and reduced corn yield under climate change impact in subsurface drained fields in southern Quebec.

Keywords: Agricultural system models; CO(2) emission; Denitrification; Mineralization,; N(2)O emission; Water quality.