施氮水平和收获时间对柳枝稷生物质产量和能源品质的影响

Effects of nitrogen level and harvest time on biomass yield and energy characteristics of switchgrass

为提高能源植物柳枝稷(Panicum virgatum)的能源品质,通过田间试验探讨黄河三角洲盐碱地施氮水平和收获时间对柳枝稷生物质产量和氮含量、灰分含量、木质纤维素含量的影响。结果表明,收获时间对柳枝稷生物质产量、氮含量、灰分、木质纤维素含量有显著(P<0.05)或极显著(P<0.01)影响。生物质产量随着施氮量的增加而增加,且在施氮量为200 kg·hm^(-2)时达到最高值;木质纤维素含量随着收获时间的推迟而增加,冬季收获含量最高,施氮水平为100 kg·hm^(-2)时含量最高;灰分含量、氮含量随收获时间推移而降低。黄河三角洲地区柳枝稷生产时施氮肥100~150kg·hm^(-2),且在冬季收获,能获得较高的能源品质。

The study evaluated the effects of nitrogen application level and harvest time on the productivity and energy characteristics of switchgrass in saline-alkali soil of Yellow River Delta in China. The results demonstrated that nitrogen could significantly increase the biomass of switchgrass. The highest yield of switchgrass was obtained at the fertilization of200 kg N·ha^（-1）（ P〈0. 01）. The biomass,ash,nitrogen and lignocellulose contents of switchgrass showed a significant response to the harvest time（ P〈0. 05）; As the harvest time delayed,the content of lignocelluloses increased,and it reached the highest in winter and the optimal nirtrogen level was 100 kg N·ha^（-1）. However,the ash content and nitrogen content showed a downward trend by delaying the harvest time. Therefore,our study suggested the high quality switchgrass will be obtained when harvest in winter and with the fertilizer application of 100 ~ 150 kg N ·ha^（-1） in the Yellow River Delta.