秸秆还田对水稻光合物质生产特征、稻米品质和土壤养分的影响

为充分利用秸秆资源,减少秸秆焚烧带来的环境污染,采用大田试验,以水稻品种盐丰47为试验材料,设置秸秆还田（S）和不还田（CK）处理,对水稻干物质积累、分配及转运、产量、稻米品质、土壤全量养分和速效养分含量进行比较研究。结果表明,S处理水稻产量低于CK,差异不显著。与CK相比,S处理显著增加了水稻成熟期叶、茎和鞘的干重及占总干重比例,但各部分干物质输出率和转运率显著降低。S处理极显著地降低了稻米的垩白粒率、垩白大小、垩白度和直链淀粉含量,提高了稻米的食味值,对稻米的糙米率、精米率和整精米率无显著影响。S处理显著提高了水稻主要生育时期土壤的有机碳、全氮、全磷、有效磷和速效钾含量,对土壤的全钾含量和C/N无显著影响。S处理水稻抽穗期土壤铵态氮含量、乳熟期和成熟期土壤铵态氮和硝态氮含量均显著低于CK。说明辽宁地区推广秸秆还田有利于培肥土壤,改善稻米品质,不会显著影响水稻产量。

Effects of Straw Returning on Photosynthetic Matter Production Characteristics,Quality of Rice and Soil Nutrients

The purpose of this study was to make full use of straw resources and reduce environmental pollution caused by straw burning. A field experiment was conducted using japonica rice Yanfeng 47 with straw returning (S) and no straw returning (CK) treatments. The accumulation, distribution and transportation of dry matter, yield and rice quality, soil total nutrient, and available nutrient content were determined. The results showed that the rice yield of S treatment was lower than that of CK, and the difference was not significant. Compared with CK, S treatment significantly increased the dry matter weight of leaves, stems, and sheaths and the dry matter weight ratio to the total plant at the mature stage, but the dry matter export rate and transformation rate of each part were significantly reduced. S treatment significantly reduced chalky grain rate, chalkiness area, chalkiness degree, and amylose content of rice and improved the taste value of rice. There was no significant difference in brown rice rate, milled rice rate, and head rice rate between CK and S treatment. S treatment significantly increased the contents of organic carbon, total nitrogen, total phosphorus, available phosphorus, and available potassium in the soil during the main growth period of rice and had no significant effects on the total potassium content and C/N of the soil. Compared with CK, S treatment significantly reduced the soil ammonium nitrogen content at the heading stage and the soil ammonium nitrogen and nitrate nitrogen content at the milking and maturity stages. These results demonstrated that the promotion of straw returning in Liaoning would not significantly affect rice yield and was beneficial for soil fertility and the improvement of rice quality.