Straw returning usually gives rise to greenhouse gas (GHG) emissions from the soil, and thus negatively affects carbon footprint (CF) of crop production. Numerous studies reported the effects of straw returning on the CF from single crop production. However, little is known about the integrated effects of different levels of straw returning on the CF and net ecosystem economic benefits (NEEB) from rice-wheat rotation. Here, we investigated the effects of different amounts of straw returning on soil CH4 and N2O emissions, GHG emissions from agricultural inputs (AIGHG), CF, and NEEB from a 2-year cycle of rice-wheat rotation. The CF was determined based on the total GHG emissions associated with crop production inputs and services. Overall, straw returning significantly increased annual CH4 emissions by 5.4-72.2% and reduced annual N2O emissions by 3.3-31.4% compared with straw removal. Straw returning remarkably increased rice grain yields by 8.1-9.9% and wheat grain yields by 10.2-21.1% compared with straw removal. The average annual AIGHG from rice-wheat rotation ranged from 3579 to 4987 kg CO2-eq ha-1. Diesel consumption played a dominant role in the AIGHG. The annual CF ranged from 0.96 to 1.31 kg CO2-eq kg-1 and increased with increasing straw returning amounts. The NEEB, which ranged from 14161 to 17413 CNY ha-1, was significantly affected by the levels of straw returning. The treatment with returning of 1/3 of preceding crop straw to the field (2.19-2.47 kg ha-1 year-1 of rice straw in the wheat season and 1.38-1.68 kg ha-1 year-1 of wheat straw in the rice season) resulted in relatively higher grain yield, the lowest CF, and the highest NEEB among all treatments, and thus can reduce CF, and increase grain yields and NEEB, and thus can be recommended as a sustainable approach to mitigate GHG emissions and increase economic benefits from rice-wheat rotation.

中文翻译：

---

中部稻麦轮作对秸秆还田水平对碳足迹和生态系统净经济效益的影响。

秸秆还田通常会引起土壤温室气体（GHG）的排放，因此会对作物生产的碳足迹（CF）产生负面影响。大量研究报告了秸秆还田对单一作物生产的CF的影响。然而，关于稻草还田对秸秆还田的不同综合效应以及稻麦轮作带来的净生态经济效益（NEEB）知之甚少。在这里，我们调查了稻麦轮换两年周期中不同秸秆还田量对土壤CH4和N2O排放，农业投入物（AIGHG），CF和NEEB排放的温室气体的影响。CF是根据与作物生产投入和服务相关的温室气体总排放量确定的。总体而言，秸秆还田使CH4的年排放量显着增加了5.4-72。与去除秸秆相比，可减少2％的年N2O排放量，减少3.3-31.4％。与去除秸秆相比，秸秆还田显着提高了稻谷产量，增幅达8.1-9.9％，小麦增产了10.2-21.1％。稻麦轮作产生的年均AIGHG范围为3579至4987 kg CO2-eq ha-1。柴油消耗在AIGHG中起着主导作用。每年的CF从0.96到1.31 kg CO2-eq kg-1不等，并且随着秸秆还田量的增加而增加。NEEB的范围从14161到17413元ha-1，受秸秆还田水平的影响很大。稻田将前茬秸秆返还田间的处理（小麦季为2.19-2.47 kg ha-1 year-1，稻谷为1.38-1.68 kg ha-1 year-1季节）导致相对较高的谷物产量，最低的CF，