Drivers of carbon flux in drip irrigation maize fields in northwest China

Abstract Background Under the escalating threat to sustainable development from global increase in carbon dioxide concentrations, variations flux farmland ecosystem and their influencing factors have attracted attention. Over past few decades, with of eddy covariance technology, fluxes farmlands been determined many countries. However, studies are very limited for drip irrigation maize arid regions northwestern China, which covers a large area where mixed mode agriculture grazing is practiced. Results To study effects on net productivity (NEE), respiration (ER), gross primary production (GPP) biome (NBP) we measured annually 2014 2018 using an system. Our results showed that field exhibited single-peak seasonal patterns during growing seasons. During 2014–2018, NEE, ER GPP drip-irrigated ranged between ? 407 ~ 729 g C m ?2 , 485.46 975.46 1068.23 1705.30 . In four 5 years, released back atmosphere was just over half fixed by photosynthesis. The mean daily were significantly correlated radiation (Rn), air temperature (Ta), leaf index (LAI) soil moisture (SWC). path analysis main driving force variation flux. When harvested removals considered, annual NBP 234 source. Conclusions This shows growth period spring under film areas northwest China. sink before harvest, but it converted into source considering emissions after harvest. influenced both environmental vegetation factors, its driver affects