Spatial variability of nitrous oxide in the Minho and Lima estuaries (Portugal)

Abstract

Summary:Nitrous oxide (N 2 O) is a potent long-lived greenhouse gas and estuaries represent potentially important sources of this biogas to the atmosphere. In this work, we analyse the first N 2 O data obtained in the Minho and Lima estuaries, and the processes and environmental factors that may regulate its production in these systems. In Variabilidad espacial del óxido nitroso en los estuarios del Miño y Lima (Portugal)Resumen: El óxido nitroso es un poderoso gas de efecto invernadero y los estuarios representan potenciales fuentes de este biogás a la atmósfera. En este trabajo se analizan los primeros datos de N 2 O obtenidos en los estuarios de Miño y Lima, así como los procesos y factores ambientales que pueden regular su producción en estos sistemas.

Seasonal and spatial controls on N2O concentrations and emissions in low-nitrogen estuaries: Evidence from three tropical systems

“…In both seasons, the N 2 O load from freshwater input is high enough to more than account for all of the emitted N 2 O ( Figure 5) and in-situ production is not needed to explain the observed patterns. In some estuaries and 415 coastal waters, a positive correlation between N 2 O and apparent oxygen utilization has been interpreted as a sign of in-situ nitrification (Nevison et al, 2003;Goncalves and Brogueira, 2017), however this correlation was not observed in the Johnstone (Figure A2a,b), and neither did we observe a negative correlation between N 2 O and NH + 4 (Figure 8b), as would be expected if nitrification were 420 consuming large quantities of NH + 4 . Another possible pathway of N 2 O production or consumption is denitrification.…”