Abstract: A research was conducted to explore the effects of nutrient addition on hay production and hay quality in Leymus chinensis,a monodominant species in the Songnen Plain. The experiment was a randomized block design,arranged precipitation (control,drought:30% rain reduction),nitrogen addition (0,pure nitrogen 100 kg·ha^-1·a^-1),phosphorus addition (0,pure phosphorus 100 kg·ha^-1·a^-1) three factors. The results showed that under the control precipitation conditions,the treatment of nitrogen addition and combined addition of nitrogen and phosphorus significantly increased the hay yield,crude protein content and ether extract content by 79.9% and 97.1%,3.2% and 2.5%,0.8% and 1.0%,respectively. However,the acid detergent lignin content significantly decreased by 4.3% and 10.1%,respectively. Under drought condition,the content of neutral detergent fiber and acid detergent fiber remained unchanged,however,the contents of crude protein and ether extract increased under nitrogen addition and combined addition of nitrogen and phosphorus. Phosphorus addition had no significant effect on both. At the same time,no matter how the precipitation changed,the content of acid detergent lignin and ash increased with phosphorus addition. Therefore,for Leymus chinensis grassland,no matter whether the precipitation is normal or less,both nitrogen addition and combined addition of nitrogen and phosphorus can improve the hay yield and quality,but phosphorus addition alone has no effect on them. In agronomic pratice,it is recommended to apply only nitrogen fertilizer or combined application of nitrogen and phosphorus,not phosphorus fertilizer alone.

Key words: Drought, Nitrogen/Phosphorus addition, Leymus chinensis, Hay yield, Quality

摘要： 本研究以松嫩平原单优种羊草(Leymus chinensis)为研究对象,分析营养添加对其产量及饲用品质的影响。试验采用全因子随机区组设计,设置降雨量(对照、减雨30%)以及氮(0、纯氮100 kg·ha^-1·a^-1)、磷(0、纯磷100 kg·ha^-1·a^-1)添加3个因素。结果表明:对照降雨条件下,氮添加和氮磷同时添加处理分别使羊草干草产量、粗蛋白含量、粗脂肪含量显著增加79.9%和97.1%,3.2%和2.5%,0.8%和1.0%,但酸性洗涤木质素含量显著降低4.3%和10.1%;减雨30%条件下,所有处理中性洗涤纤维和酸性洗涤纤维含量不变,而氮添加与氮磷同时添加时粗蛋白和粗脂肪含量有所提高,磷添加对二者均无显著影响;同时,不论降雨量如何变化,磷添加均使酸性洗涤木质素和灰分含量增加。因此,就羊草草地而言,无论降雨正常还是干旱,氮添加和氮磷同时添加均能提高羊草产量和品质,而磷添加对牧草产量和品质没有促进作用。实际生产中,推荐只施氮肥或者氮磷配施,不单独施用磷肥。

关键词: 干旱, 氮/磷添加, 羊草, 干草产量, 饲用品质