Masaka et al., 2014. Nitrous oxide emissions from wetland soil amended with inorganic and organic fertilizers

Masaka, J., Nyamangara, J., Wuta, M., 2014. Nitrous oxide emissions from wetland soil amended with inorganic and organic fertilizers. Archives of Agronomy and Soil Science 60, 1363-1387.

Abstract

Agricultural soils are a primary source of anthropogenic trace gas emissions, and the subtropics contribute greatly, particularly since 51% of world soils are in these climate zones. A field experiment was carried out in an ephemeral wetland in central Zimbabwe in order to determine the effect of cattle manure (1.36% N) and mineral N fertilizer (ammonium nitrate, 34.5% N) application on N₂O fluxes from soil. Combined applications of 0 kg N fertilizer + 0 Mg cattle manure ha⁻¹ (control), 100 kg N fertilizer + 15 Mg manure ha⁻¹ and 200 kg N fertilizer + 30 Mg manure ha⁻¹ constituted the three treatments arranged in a randomized complete block design with four replications. Tomato and rape crops were grown in rotation over a period of two seasons. Emissions of N₂O were sampled using the static chamber technique. Increasing N fertilizer and manure application rates from low to high rates increased the N₂O fluxes by 37–106%. When low and high rates were applied to the tomato and rape crops, 0.51%, 0.40%, and 0.93%, 0.64% of applied N was lost as N₂O, respectively. This implies that rape production has a greater N₂O emitting potential than the production of tomatoes in wetlands.