A review of indirect N2O emission factors from agricultural nitrogen leaching and runoff to update of the default IPCC values

Linlin Tian; Yanjiang Cai; Hiroko Akiyama

doi:10.1016/j.envpol.2018.11.016

A review of indirect N₂O emission factors from agricultural nitrogen leaching and runoff to update of the default IPCC values

Environ Pollut. 2019 Feb:245:300-306. doi: 10.1016/j.envpol.2018.11.016. Epub 2018 Nov 9.

Authors

Linlin Tian¹, Yanjiang Cai¹, Hiroko Akiyama²

Affiliations

¹ State Key Laboratory of Subtropical Silviculture, Zhejiang A & F University, Hangzhou, 311300, China; Institute for Agro-Environmental Sciences, National Agriculture and Food Research Organization, 3-1-3, Kannondai, Tsukuba, Ibaraki, 305-8604, Japan.
² Institute for Agro-Environmental Sciences, National Agriculture and Food Research Organization, 3-1-3, Kannondai, Tsukuba, Ibaraki, 305-8604, Japan. Electronic address: ahiroko@affrc.go.jp.

PMID: 30447472
DOI: 10.1016/j.envpol.2018.11.016

Abstract

Indirect N₂O emissions from agricultural nitrogen (N) leaching and runoff in water bodies contribute significantly to the global atmospheric N₂O budget. However, considerable uncertainty regarding this source remains in the bottom-up N₂O inventory. Indirect N₂O emission factor associated with N leaching and runoff (EF₅; kg N₂ON per kg of NO₃^--N) incorporate three components for groundwater and surface drainage (EF_5g), rivers (EF_5r), and estuaries (EF_5e). The 2006 IPCC default EF₅ value was based on a small number of studies available at the time. Here we present the synthesis of 254 measurements of EF₅, dissolved N₂O, and nitrate from 106 studies. Our results do not support the further downward revision of EF_5g by the IPCC and suggest an upward revision of EF_5g of 0.0060. The emission factors for groundwater and springs (0.0079) was higher than that for surface drainage (0.0040). The emission factor for lakes, ponds, and reservoirs was 0.0012, whereas that for rivers was 0.0030, and a combined EF_5r was 0.0026. Estimated EF_5r and EF_5e (0.0026) values from the study were close to the current IPCC default values (0.0025 each). We estimated an updated default EF₅ value of 0.01 for the refinement of IPCC guidelines.

Keywords: Emission factor; Global warming; IPCC methodology; Nitrate leaching; Nitrous oxide.

Publication types

Review

MeSH terms

Agriculture / methods*
Air Pollutants / analysis*
Environmental Monitoring / methods*
Groundwater / chemistry
Nitrates / analysis
Nitrogen / analysis*
Nitrogen Cycle
Nitrous Oxide / analysis*
Rivers / chemistry
Water Pollutants, Chemical / analysis*

Substances

Air Pollutants
Nitrates
Water Pollutants, Chemical
Nitrous Oxide
Nitrogen