Effect of irrigation and planting methods on water and nitrogen utilization and loss in paddy fields
[Objective]To explore the effect characteristics of irrigation and planting methods on nitrogen loss and water utilisation in rice fields.[Method]We selected four planting methods:hand-transplanting(HT),seedling throwing(ST),machine-transplanting(MT)and direct seeding(DS),and two irrigation modes:flooding irrigation(FI)and intermittent irrigation(II),and carried out a plot experiment on late rice to analyse and evaluate the characteristics of paddy rice field water balance,water-use efficiency,and nitrogen runoff and leaching loss under different irrigation and planting modes.[Result]The results showed that:the water use efficiency of different irrigation modes was higher in intermittent irrigation,and the water use efficiency of different planting modes was HT(ST)>MT>DS.The water quantity,water consumption,leakage,and evapotranspiration were reduced by 9.87%-22.11%,9.65%-21.49%,1.46%-3.64%,and 11.18%-27.15%,respectively,for the treatments of each cropping method under the intermittent irrigation pattern as compared to the flooded irrigation pattern.Planting method and irrigation pattern had a greater impact on nitrogen runoff and leaching loss,which accounted for 0.02%-0.17%and 2.33%-3.53%of the applied fertiliser,respectively.Under the same irrigation pattern,the nitrogen surface runoff loss and leaching loss of different planting treatments were DS>MT>ST>HT.The leaching amount and nitrogen leaching loss of different treatments varied in each fertility period under the influence of irrigation pattern and planting method,among which the loss was higher in seedling and pre-tiller stage,which accounted for the proportion of the whole fertility period,respectively,43.35%-53.79%and 6.67%.53.79%,and 6.67%-22.38%,respectively.With the combined irrigation pattern and planting method,the yield and water use efficiency of different treatments were the highest in HT-II and the lowest in DS-FI,while the nitrogen leaching loss was the lowest in HT-II and the highest in DS-FI.[Conclusion]Intermittent irrigation is beneficial to improve rice yield and water use efficiency,water consumption and nitrogen loss of direct seeding rice are higher than that of transplanted rice,and hand-planting with intermittent irrigation is beneficial to improve water use efficiency of rice and reduce nitrogen loss from paddy fields.In the production practice of double-season late rice,the environmental effect of paddy field can be improved by strengthening the water management at seedling and pre-tiller stages to reduce paddy leaching and nitrogen leaching loss.
ricefull growth periodplanting methodirrigation modewater use efficiencynitrogen loss
国家科技期刊平台
NSTL
万方数据
