Abstract:

In order to improve the pasture grass yield of alpine meadow and fertilizer technology, the influences of different nitrogen types and dose rates on alpine meadow biomass, plant nutrients and soil nutrients were studied using random block design with ammonium sulfate fertilizer, calcium nitrate fertilizer and urea fertilizer. The results showed that the alpine meadow plant aboveground biomass, plant total nitrogen, soil total nitrogen, soil ammonium nitrogen of ammonium sulfate treatment were significantly higher than that of urea treatment and control(P<0.05). When applying ammonium sulfate of 200 kg·hm^-2, aboveground biomass, plant total nitrogen, soil total nitrogen reached the maximum. Correlation analysis showed that plant total nitrogen, soil ammonium nitrogen and aboveground biomass were significantly positive correlated with ammonium sulfate fertilizer. There was significantly positive correlation between soil nitrate nitrogen and calcium nitrate fertilizer. Principal component analysis indicated that ammonium sulfate fertilizer and soil ammonium nitrogen constituted the first principal component. These findings suggested that both soil ammonium nitrogen and aboveground biomass of alpine meadow significantly increased using ammonium nitrogen fertilizer compared with using calcium nitrate and urea fertilizer. It was the best dose rate that fertilizer dose rate was 200 kg·hm^-2.

Key words: Alpine meadow, Application of nitrogen, Aboveground biomass, Soil nutrients

摘要：

为提高称多县高寒草甸草场牧草产量、完善牧草营养施肥技术,采用随机区组试验,以硫酸铵、硝酸钙和尿素为试验材料,探讨不同形态氮肥及施肥水平对称多县高寒草甸地上植物量、植物养分及土壤养分的影响。结果表明:硫酸铵处理的高寒草甸地上植物量、植物全氮、土壤全氮、土壤铵态氮均显著高于尿素处理和对照(P<0.05);当硫酸铵施用量为200 kg·hm^-2时,地上植物量、植物全氮、土壤全氮均为最大值。相关性研究表明硫酸铵与植物全氮、土壤铵态氮和地上植物量成显著正相关。主成分分析表明,硫酸铵和土壤铵态氮为第一主成分。因此确定施用硫酸铵后称多县高寒草甸增产效果最明显,尿素增产效果次之,硝酸钙效果非佳。施肥量以200 kg·hm^-2为最适施肥量。

关键词: 高寒草甸, 施氮素, 生物量, 土壤养分