等量蚕豆鲜秆还田配施不同比例化肥对单季晚稻的影响

Effect of the same amount of faba bean fresh straw returning with different ratios of chemical fertilizer on single cropping late rice

2012年4—11月在浙江省丽水市碧湖镇下季村进行田间试验,研究等量蚕豆鲜秆还田配施不同比例常规用量化肥对单季晚稻养分吸收、养分利用率和产量的影响.试验设置不翻压蚕豆鲜秆和不施化肥（CK）、常规用量化肥（CF）及翻压15 t·hm-2（GM15）蚕豆鲜秆配施0、20%、40%、60%和80%CF共7个处理.结果表明：在所有的蚕豆鲜秆还田配施化肥处理中,GM15＋60%CF和GM15＋80%CF处理的水稻N、P、K养分的总吸收量高于其他处理,但GM15＋40%CF和GM15＋60%CF处理的水稻N、P、K养分的农学利用效率最高.水稻稻谷产量与N、P、K的养分农学利用效率和养分生理利用效率之间均有显著的相关性,因此养分农学利用效率和养分生理利用效率2个指标可以用来准确综合评价N、P、K养分的肥效.与CK相比,CF和蚕豆鲜秆还田配施化肥处理的稻谷产量分别提高25.0%和6.1%~29.2%.在蚕豆-单季晚稻耕作制中,蚕豆鲜秆异地还田量15 t·hm-2不会使单季晚稻苗期产生僵苗现象.本试验条件下,从提高水稻产量、水稻养分利用率及降低环境风险的角度出发,蚕豆鲜秆异地还田量为15 t·hm-2时,以配施常规用量化肥60%为宜.

A field experiment was conducted on paddy soil derived from alluvial materials at Bihu Town,Lishui City,Zhejiang Province,China to explore the effects of combined application of faba bean fresh straw and different-rate chemical fertilizer on nutrient uptake,nutrient use efficiencies,and yields of single cropping late rice and to determine the optimal rate of chemical fertilizer under the condition of application of faba bean fresh straw at the rate of 15 t·hm-2（ GM15） in 2012,April to December. The experiments consisted of 7 treatments： CK（ no fertilizers）,CF（ conventional chemical fertilizer rate）,and combined application of 15 t·hm-2of faba bean fresh straw and 0%,20%,40%,60% and 80% of the conventional chemical fertilizer rate. The results showed that the highest total uptake amounts of N,P and K by the aboveground part were obtained from the treatments of GM15＋60% CF and GM15＋80% CF,but the highest nutrient agronomy use efficiencies of N,P and K in rice grains were obtained from the treatments of GM15＋60% CF and GM15＋40%CF. The agronomy use efficiencies and physiological use efficiencies of N,P,and K were significantly correlated with rice grain yields,thus they could be used for accurate comprehensive evaluation of fertilizer efficiencies of N,P,and K. Compared with no fertilizer treatment,the treatments of 100% CF and combined application of faba bean fresh straw and different-rate chemical fertilizer increased rice gain yields by 25. 0% and 6. 1%-29. 2%,respectively. In the cropping system of faba bean-single cropping late rice,returning of 15 t·hm-2faba bean fresh straw to the paddy field did not result in the runt seedling of rice. From the point of improving fertilizer use efficiency and reducing environmental risk perspective,the optimum rate of chemical fertilizer was 60% of the conventional chemical fertilizer rate when 15 t·hm-2of faba bean fresh straw was applied.