Emission chamber and ambient field initial atmospheric temperature, vapour pressure deficit and carbon dioxide concentration during the cotton-wheat-fallow rotation and greenhouse gas emission data (2015-2016)

This data was used to investigate the emissions of greenhouse gases — carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) — from different soil positions (hill, skip furrow, irrigation furrow) in a cotton-wheat-fallow rotation system under irrigation in Narrabri, Australia. The research spans a two-year period and aims to understand the spatial variability of emissions and their relation to soil and atmospheric conditions. Nitrous oxide emissions during the cotton season averaged 2.07 ± 0.13 kg N2O-N ha-1, representing 0.86% of applied fertilizer nitrogen, with emissions occurring in hills and furrows due to nitrogen transport. Methane was consistently absorbed by the soil and contributed a small amount to the overall greenhouse gas budget. Carbon dioxide emissions were higher from furrows, while hills functioned as carbon sinks during cropping seasons. The rotation exhibited a net soil carbon loss of approximately 4.1 ± 0.5 t C ha-1, indicating a need for management strategies to increase carbon inputs during fallow periods. Recommendations include eliminating bare fallows, using mulches or cover crops in furrows, and optimizing nitrogen fertilizer timing to reduce emissions and improve nitrogen use efficiency.