Abstract: Abstract: With growing concern on climate change, agriculture has received attention over last few decades as it is a significant contributor to global warming and total greenhouse gas (GHG) emission. GHG emissions of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) can be affected by various field managements. Gravel mulching technology, as a distinct field management technique, has been long used to decrease water evaporation and improve crop production in the semi-arid Loess Plateau of northwest China, but systematic field studies concerning the impacts of surface gravel mulching on dryland agricultural soils water and heat conditions and GHG emissions are scarce. Therefore, we conducted a field study of wheat-maize rotation cycle in Yangling District of Shaanxi Province in the year of 2014-2015. The annual GHG emissions (CO2, CH4 and N2O) were monitored using a static opaque chamber and chromatography method. This study focuses on the interactive role of gravel mulching and irrigation practices on both crop yield and GHG emissions. We also calculated the global warming potential (GWP) and greenhouse gas emissions intensity (GHGI) to evaluate the farmland ecological effect and GHG reduction effect. In this experiment, 4 field treatments were arranged with 2 gravel mulching levels (M0: No mulching, M1: covering 100% of soil surface) and 2 supplemental irrigation levels at key growing periods (W0: without irrigation, W1: 50 mm). The results showed that: 1) Compared with the control treatment of W0M0, the annual wheat-maize yields were significantly increased by 18.1%, 32.6% and 51.8% under the other 3 treatments of W1M0, W0M1 and W1M1, respectively; the annual CO2 emissions were decreased by 7.8%, 12.1% and 18.0% under W1M0, W0M1 and W1M1, respectively. And there was not significant difference for annual N2O emissions for different treatments. The total annual absorption amounts of methane were increased by 32.5%, 80.2% and 124.3% under W1M0, W0M1 and W1M1 compared with the W0M0, respectively. 2) Gravel mulching gives positive contribution to the soil temperature and soil moisture. The correlation analysis of annual GHG emissions with soil temperature (5 cm) or soil water content (10 cm) under different experimental treatments over the wheat-maize growing period indicated that, the dependence of soil CO2 emissions on soil water and soil temperature was pronounced for the 4 treatments with significant correlations (P<0.05), while the dependence of soil CH4 or N2O emissions on soil water and temperature was partly with significant correlations (P<0.05). 3) Annual GWP values were more complicated in all treatments ranging from 522.8±204.6 to 629.5±328.5 kg/hm2 (CO2 equivalent) Compared with W0M0, irrigation practice could decrease the value of GWP, while gravel mulching practice could increase the value of GWP, and the interaction of gravel mulching coupled with irrigation could balance the GWP. 4) For the W1M0, W0M1 and W1M1 treatments, GHGI was significantly decreased compared with W0M0 by the values of 14.9%, 20.7% and 33.6%, respectively. The above results suggested the application of gravel mulching coupled with irrigation may obtain a balance between the increase of crop yield and the decrease of GHG emissions. Overall, gravel mulching practices could effectively increase soil moisture and temperature, and greatly lower the GHGI with the significant increase of crop yield. The basic case study provides a feasible way to realize stable crop productivity increase and GHG emissions reduction in arid and semi-arid region.