Long-term straw incorporation regulates greenhouse gas emissions from biodegradable film farmland, improves ecosystem carbon budget and sustainable maize productivity

There is an urgent need to improve traditional film-mulched cultivation to minimize greenhouse gas emissions and increase crop yields simultaneously. Mulching biodegradable films and straw returning are recognized as potential methods to achieve the above goal. However, the comprehensive study of the long-term application of biodegradable film combined with straw incorporation on maize yield, system carbon balance and applicability in future climate conditions is very limited. Therefore, a 6-years two-factor positioning experiment was set up in a typical semi-arid area of the Loess Plateau (2015–2021). Factor one is different film mulching cultivation measures, including double ridge- furrow (D) and flat planting (F), and factor two is straw incorporation (S) or not (NS), forming four treatments (DS, FS, D and F). Comparing the difference of water use efficiency (WUE), temperature uses efficiency (TUE), carbon emission (Rh and CH4), nitrogen emission (N2O), and maize yield among different treatments. The results showed that straw incorporation enhanced the capture and utilization of precipitation and solar energy of different film-mulching cultivation methods under different climate types and increased maize grain yield by 5.97 % on average. Although straw incorporation increased the cumulative emission of Rh and N2O by 19.76 % and 37.87 %, it significantly improved the net ecosystem carbon budget (NECB). It stabilized the carbon footprint (CF) per unit grain yield between − 0.005 and − 0.5 kg eq-CO2 kg−1. These commercialized environmental benefits further increased net income (NI) by 326.31 ¥ ha−1. Compared with FS, the average WUE and TUE, cumulative net ecosystem carbon budget (NECB) and NI of DS from 2019 to 2021 were 5.31 %, 9.05 %, 1.53-fold and 4.89 % higher, respectively. Long-term straw incorporation improved the use efficiency of the natural resource of spring maize, kept the annual grain yield at a high level, and adjusted the carbon budget, making the ecosystem a net “sink” of GHG emissions. The results reflected higher economic benefits (direct and commercial environmental benefits). In the long-term monitoring, DS showed better stability and superiority than FS in the above aspects. Double-ridge furrow sowing with full biodegradable film mulching combined with straw incorporation provides a new film mulching strategy for agricultural production and carbon management in semi-arid rain-fed areas and similar agroecosystems.