不同氮水平对马铃薯块茎和土壤NO_3~--N含量的影响

目的]为马铃薯科学施肥提供理论依据。方法]设置N1:传统氮肥施用量;N2:80%推荐氮肥施用量、N3:推荐氮肥施用量、N4:120%推荐氮肥施用量4个氮水平,研究不同水平对马铃薯块茎和土壤NO3--N含量的影响。结果]马铃薯块茎内NO3--N含量随施氮量的增加而增加,但均未超标。N2处理马铃薯产量最高,块茎NO3--N为431.56 mg/L。随着施氮量的增加,氮淋失程度加深,土壤中的NO3--N含量逐渐增加。各处理土壤NO3--N含量随土层的加深有不同程度的递减。N2处理的氮素供应与马铃薯对N素的吸收基本达到了平衡。结论]随着氮水平的提高,马铃薯块茎和土壤中的NO3--N含量均呈上升趋势。

Effects of Different N Levels on NO3--N Contents in Potato Tubers and Soil

Objective] The study aimed to supply theoretical foundation for scientific fertilization of potato.Method] Four N levels of traditional N fertilization amount(N1),80% of recommended N fertilization amount(N2),recommended N fertilization amount(N3),120% of recommended N fertilization amount(N4) were set up to study the effects of different levels on NO3--N contents in potato tubers and soil.Result] NO3--N contents in potato tubers was increased along with the increment of N fertilization amount,but didn't exceed the standard.In N2 treatment,the potato yield was highest and NO3--N content in tuber was 431.56 mg/L.The leaching degree of N deepened and NO3--N content in soil was increased gradually along with the increment of N fertilization amount.The NO3--N contents in soil in various treatments had gradual decrement to different degrees along with the deepening of soil layers.In N2 treatment,the N supplication and the N adsorption of potato basically reached balance.Conclusion] The NO3--N contents in both potato tubers and soil showed increasing trend along with the enhancement of N level.