Many studies have shown that straw return to the field can promote the production of photosynthetic material for crops, and thus increase crop yields. Due to the different effects of straw return to the field in different areas, there are fewer studies on the photosynthetic characteristics and yield of rice after straw return to the field in Northeast soda saline–alkali rice area, and it is not clear whether straw return reduces the amount of nitrogen fertilizer used in the area. Using the local large-scale cultivar Baijing 1 as the material, we studied the effects of straw return with nitrogen fertilizer (0, 90, 180, 270 and 360 kg ha⁻¹) on the photosynthetic characteristics and seed yield of rice in saline–sodic areas through a 2 years field trial. The results of this experiment showed that rice yield was highly significantly and positively correlated with canopy total photosynthetically active radiation (TIPAR), leaf area index (LAI), relative chlorophyll content (SPAD), net photosynthetic rate (P_n), stomatal conductance (g_s), transpiration rate (T_r), Rubisco activity and PSII maximum photochemical efficiency (F_v/F_m) but significantly and negatively correlated with intercellular CO₂ concentration (C_i). Compared with the treatment without straw return, straw return increased TIPAR, LAI, SPAD, P_n, g_s, T_r and yield of rice when N ≥ 180 kg N ha⁻¹. The rice yield was the highest when the nitrogen application rate was 270 kg ha⁻¹. The yield of straw return treatment under this nitrogen fertilizer was 8.01 t ha⁻¹, and the yield of no straw return treatment was 7.52 t ha⁻¹ (average 2 years). In addition, the results suggested that approximately 36–43% of chemical N fertilizer reduction would not affect rice yield with straw addition. Our results suggest that straw return is a promising management practice in soda saline–alkali rice areas that can reduce the application of mineral nitrogen fertilizer without losing rice yield.

许多研究表明，秸秆还田可以促进作物光合物质的产生，从而提高作物产量。由于不同地区秸秆还田效果不同，对东北碱盐碱稻区秸秆还田后水稻光合特性和产量的研究较少，尚不清楚秸秆还田是否还田。减少该地区使用的氮肥量。以当地规模化栽培品种白净1号为材料，研究了秸秆还田施氮肥（0、90、180、270和360 kg ha ^-1) 通过 2 年的田间试验，对盐碱区水稻的光合特性和种子产量进行了研究。本试验结果表明，水稻产量与冠层总光合有效辐射（TIPAR）、叶面积指数（LAI）、相对叶绿素含量（SPAD）、净光合速率（_Pn ）、气孔导度（g _s )、蒸腾速率 ( T _r )、Rubisco 活性和 PSII 最大光化学效率 ( F _v / F _{m ) 但与细胞间 CO 2}浓度 ( C _i ) 呈显着负相关）。与不还草处理相比，当N≥180 kg N  ha ^-1时，秸秆还田提高了TIPAR、LAI、SPAD、P _n、g _s、T _r和水稻产量。施氮量为270 kg ha ^-1时水稻产量最高。该氮肥下秸秆还田处理产量为8.01 t ha ^-1，秸秆不还田处理产量为7.52 t ha ^-1（平均2年）。此外，结果表明大约 36-43% 的化学N施肥不影响稻草增产。我们的研究结果表明，秸秆还田是苏打盐碱稻区一种很有前景的管理实践，可以减少矿物氮肥的施用而不损失水稻产量。