秸秆还田对苏打盐碱地水稻氮肥利用及产量的影响

Effects of Straw Returning on Nitrogen Fertilizer Utilization and Yield of Rice in Soda Saline-alkali Land

为探究秸秆还田对苏打盐碱地水稻氮肥利用及产量的影响,试验于2017—2018年采用随机区组试验设计,设置无秸秆还田(S0)、秸秆40%还田(S1)、秸秆60%还田(S2)、秸秆80%还田(S3)和秸秆全量还田(S4)共5个秸秆还田水平,测定苏打盐碱地水稻的氮素积累量、氮肥偏生产力、氮肥农学利用率、氮素吸收利用率、干物质积累量、产量及其构成因素等指标。结果表明:秸秆还田可以增加水稻氮素积累量;与其他秸秆还田处理相比,S3处理的氮肥偏生产力、氮肥农学利用在2年平均分别增加22.05%~32.55%和27.55%~45.13%;秸秆还田显著提升水稻有效穗数、穗粒数和结实率,两年间干物质积累量分别比对照S0提高14.23%~35.41%和20.04%~53.80%,产量分别增加1.20~3.25 t/hm^2和1.78~2.89 t/hm^2。因此这说明秸秆还田可以提高苏打盐碱地水稻氮肥利用效率,促进水稻干物质积累,增加水稻产量。

In order to explore the effects of straw returning on nitrogen utilization and yield of rice in saline-sodic soil,a randomized block experiment design was adopted in 2017-2018.Five straw returning levels were set,including no straw returning to the field(S0),40%straw returning to the field(S1),60%straw returning to the field(S2),80%straw returning to the field(S3)and full straw returning to the field(S4).The indexes of nitrogen accumulation,nitrogen partial factor productivity,nitrogen agronomic efficiency,nitrogen recovery efficiency,dry matter accumulation,yield and yield components of rice in saline-sodic soil were measured.The results showed that straw returning could increase nitrogen accumulation of rice.Compared with other straw returning treatments,nitrogen partial factor productivity and nitrogen agronomic efficiency of S3 treatment respectively increased by 22.05%-32.55%and 27.55%-45.13%on average in two years.Straw returning significantly increased the number of effective panicles per unit area,the number of grains per panicle and the seed setting rate of rice.The dry matter accumulation in the two years increased by14.23%-35.41%and 20.04%-53.80%,respectively,and the yield increased by 1.20-3.25 t/hm^2 and 1.78-2.89 t/hm^2,respectively.Therefore,saline-sodic soili straw returning can improve nitrogen use efficiency of rice,promote dry matter accumulation of rice,and increase rice yield.