关键词: 秸秆还田, 有机肥耦合, 河淤土, 土壤肥力, 水稻产量, 稻米品质

Abstract: 【Objective】To identify the optimal coupling pattern of straw returning and organic fertilizer in river alluvial soil regions of the lower reaches of the Yangtze River.【Methods】A typical low-yield river alluvial soil in Lishui District,Nanjing City,was selected as the research object. Five treatments were set up,including conventional control（CK）,straw with two-pass rotary tillage+organic fertilizer（OF+RT）,straw with two-pass plough tillage+organic fertilizer（OF+DP）,straw with one-pass plough tillage and one-pass rotary tillage+organic fertilizer（OF+DP+RT）,and organic fertilizer+straw with one-pass plough tillage and one-pass rotary tillage（OF→DP+RT）. The application rate of organic fertilizer was 9 000.00 kg/hm² in four organic fertilizer treatments. Through consecutive two-season field experiments,the soil physical and chemical properties,rice yield and its components,and rice quality-related indicators under different straw returning methods and organic fertilizer application during the rice season were measured and analyzed.【Results】Two consecutive seasons of straw-organic fertilizer coupling measures achieved stable rice yield;the comprehensive performance of OF→DP+RT treatment was the best,and the soil organic matter content was 10.14 g/kg,which was significantly higher than that of CK （P<0.05）;the contents of available phosphorus and available potassium were the highest in all treatments,reaching 14.80 and 195.00 mg/kg,respectively,which increased by 16.50% and 11.40% compared with CK;the grain yield was 8 760.00 kg/hm² and 1 000-grain weight was 24.30 g,which had no significant difference compared with CK（P>0.05）;the rice grain protein content（75.20 g/kg） and milled rice rate（76.50%） were significantly higher than those of CK（P<0.05）.【Conclusions】 The organic fertilizer+straw with one-pass plough tillage and one-pass rotary tillage can maintain topsoil fertility and improve rice yield and quality while breaking the plough pan layer.

Key words: Straw returning, Organic fertilizer coupling, River alluvial soil, Soil fertility, Rice yield, Rice quality