秸秆全量还田下土壤氮素特征对耕作措施的响应

为揭示北疆地区秸秆全量还田下不同耕作措施对土壤氮素特征的影响,进而筛选出适宜北疆复播大豆资源高效利用的耕作措施。于2019年进行了复播大豆田间试验,在冬小麦收获后秸秆全量还田条件下,设置了翻耕（TS）、翻耕覆膜（TPS）和免耕秸秆覆盖（NTS）3种耕作措施处理,研究不同耕作措施对复播大豆土壤铵态氮、硝态氮及氨挥发的影响。结果表明,复播大豆花期施肥后,土壤氨挥发速率和积累量表现为TPS>TS>NTS;不同耕作措施下土层0~20cm硝态氮和铵态氮含量差异显著,0~20cm耕层TPS和TS处理土壤硝态氮含量分别较NTS处理高17.12%和18.45%,铵态氮含量分别高82.76%和4.66%。综合考虑认为,秸秆全量还田下,北疆复播大豆适宜的耕作方式为翻耕覆膜。

Effects of Tillage Measures on Soil Nitrogen Characteristics under Total Straw Returning

To determine the effects of various tillage techniques on nitrogen characteristics under straw returning, and to choose the most appropriate tillage technique for the effective use of summer soybean resources in northern Xinjiang, three treatments made up the trial in 2019, moldboard plough tillage with straw returning (TS), tillage+film mulching (TPS), and no-till with straw returning (NTS). The effects of different tillage measures on soil ammonium nitrogen, nitrate nitrogen and ammonia volatilization were studied. The results showed that after fertilization at the flowering stage of the reseeded soybean, the ammonia volatilization rate and accumulation in the soil showed TPS > TS > NTS. Different tillage measures had significant differences in nitrate nitrogen and ammonium nitrogen in 0-20cm soil. The average contents of nitrate nitrogen in 0-20cm with TPS and TS treatments were 17.12% and 18.45% higher than that NTS treatment, and ammonium nitrogen contents were high in 82.76% and 4.66%, respectively. Therefore, the tillage plus film mulching and with straw returning (TPS) is the suitable tillage measure for replanting summer soybean.