当前国内外开展了很多农业温室气体对气候变化的响应研究,但气候变化对农业温室排放的影响机制研究还很少见.本文利用国际上广泛应用的生物地球化学过程模型DNDC模型,模拟了中国过去40年(19712010年)气候变化对水稻田温室气体排放的影响. 结果表明:与19711990年相比,19912010年的全国稻季平均气温上升了0.49 ℃,稻季平均降雨上升了11 mm;由于稻季气候变化导致全国水稻田19912010年的平均CH_4排放量上升了0.25 kg C·hm~ (-2),平均N_2O排放量上升了0.25 kg N·hm~(-2).表明温度升高会促进CH_4排放,降雨量增加会促进N_2O排放,气候变化影响了水稻温室气体排放机制.
英文摘要:
In contrast to a large body of literature assessing the impact of agriculture greenhouse gas (GHG) emissions on climate change, there is a lack of research examining the impact of climate change on agricultural GHG emissions. This study employed the DNDC v9.5, a state-of-art biogeochemical model, to simulate greenhouse gas emissions in China' s rice-growing fields during 1971-2010. The results showed that owing to temperature rising (on average 0.49 ℃ higher in the second 20 years than in the first 20 year) and precipitation increase (11 mm more in the second 20 years than in the first 20 years) during the rice growing season, CH_4 and N_2O emissions in paddy field increased by 0.25 kg C·hm~ (-2) and 0.25 kg N·hm~ (-2),respectively. The rising temperature accelerated CH_4 emission and N_2O emission increased with precipitation. These results indicated that climate change exerted impact on the mechanism of GHG emissions in paddy field.