Nitrous Oxide from Heterogeneous Agricultural Landscapes: Source Contribution Analysis by Eddy Covariance and Chambers

2011 ◽  
Vol 75 (5) ◽  
pp. 1829-1838 ◽  
Author(s):  
Marina Molodovskaya ◽  
Jon Warland ◽  
Brian K. Richards ◽  
Gunilla Öberg ◽  
Tammo S. Steenhuis
Keyword(s):  
Nitrous Oxide ◽  
Eddy Covariance ◽  
Agricultural Landscapes ◽  
Source Contribution ◽  
Contribution Analysis

Source contribution analysis of tropospheric NO2 based on two-dimensional MAX-DOAS measurements

2019 ◽  
Vol 210 ◽  
pp. 186-197 ◽  
Author(s):  
Taiping Yang ◽  
Fuqi Si ◽  
Yuhan Luo ◽  
Kai Zhan ◽  
Ping Wang ◽  
...  
Keyword(s):  
Two Dimensional ◽  
Source Contribution ◽  
Contribution Analysis ◽  
Tropospheric No2

scholarly journals Widespread nitrous oxide undersaturation in farm waterbodies creates an unexpected greenhouse gas sink

2019 ◽  
Vol 116 (20) ◽  
pp. 9814-9819 ◽  
Author(s):  
Jackie R. Webb ◽  
Nicole M. Hayes ◽  
Gavin L. Simpson ◽  
Peter R. Leavitt ◽  
Helen M. Baulch ◽  
...  
Keyword(s):  
Nitrous Oxide ◽  
Inorganic Nitrogen ◽  
Generalized Additive Models ◽  
Regional Analysis ◽  
Freshwater Ecosystems ◽  
Agricultural Landscapes ◽  
Additive Models ◽  
Water Column Stability ◽  
Flowing Waters

Nitrogen pollution and global eutrophication are predicted to increase nitrous oxide (N2O) emissions from freshwater ecosystems. Surface waters within agricultural landscapes experience the full impact of these pressures and can contribute substantially to total landscape N2O emissions. However, N2O measurements to date have focused on flowing waters. Small artificial waterbodies remain greatly understudied in the context of agricultural N2O emissions. This study provides a regional analysis of N2O measurements in small (<0.01 km2) artificial reservoirs, of which an estimated 16 million exist globally. We show that 67% of reservoirs were N2O sinks (−12 to −2 μmol N2O⋅m−2⋅d−1) in Canada’s largest agricultural area, despite their highly eutrophic status [99 ± 289 µg⋅L−1 chlorophyll-a (Chl-a)]. Generalized additive models indicated that in situ N2O concentrations were strongly and nonlinearly related to stratification strength and dissolved inorganic nitrogen content, with the lowest N2O levels under conditions of strong water column stability and high algal biomass. Predicted fluxes from previously published models based on lakes, reservoirs, and agricultural waters overestimated measured fluxes on average by 7- to 33-fold, challenging the widely held view that eutrophic N-enriched waters are sources of N2O.

Sign in / Sign up

Export Citation Format

Share Document