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In many smallholder farming areas southern Africa, the cultivation of seasonal wetlands (dambos) represent an important adaptation to climate change. Frequent droughts and poor performance of rain-fed crops in upland fields have resulted in mounting pressure to cultivate dambos where both organic and inorganic amendments are used to sustain crop yields. Dambo cultivation potentially increases greenhouse gas (GHG) emissions. The objective of the study was to quantify the effects of applying different rates of inorganic nitrogen (N) fertilisers (60, 120, 240 kg N ha⁻¹) as NH₄NO₃, organic manures (5,000, 10,000 and 15,000 kg ha⁻¹) and a combination of both sources (integrated management) on GHG emissions in cultivated dambos planted to rape (Brassica napus). Nitrous oxide (N₂O) emissions in plots with organic manures ranged from 218 to 894 µg m⁻² h⁻¹, while for inorganic N and integrated …