Greenhouse gas (CO2, CH4, N2O) emissions to the atmosphere from a small lowland stream in Czech Republic

Abstract

Greenhouse gas emissions from a small lowland stream in the Czech Republic were quantified using three methods. Emissions from the sediments measured with the static chamber method averaged 1.0 ′ 0.1 g CO 2 m - 2 d - 1 , 6.5 ′ 1.5 mg CH 4 m - 2 d - 1 and 0.31 ′ 0.04mg N 2 O m - 2 d - 1 , while calculated fluxes of gases across the air-water interface were much higher, in average 9.1 ′ 0.7 g CO 2 m - 2 d - 1 , 39.2 ′ 3.6mg CH 4 m - 2 d - 1 and 10.4 ′ 1.6 mg N 2 O m - 2 d - 1 . In addition, emissions measured using the floating chamber method averaged 3.7 ′ 0.3 g CO 2 m - 2 d - 1 , 16.0 ′ 3.4 mg CH 4 m - 2 d - 1 and 1.7 ′ 0.2 mg N 2 O m - 2 d - 1 . No relationship between temperature and gas emissions into the atmosphere was found. Gas fluxes across the air-water interface were significantly correlated with surface water concentrations, but emissions from the sediments showed no relationship with those concentrations in either the surface or interstitial water. Regardless of the method used, our results suggest that the Sitka stream is a source of gases into the atmosphere, and losses of carbon and nitrogen such as the fluxes of these greenhouse gases out into the ecosystem can participate significantly in river self-purification.