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于2005年9月在祁连山北坡沿海拔梯度测定了青海云杉(Picea crassifolia)叶片氮、磷含量.结果表明,青海云杉叶氮、磷平均含量分别为9.75和0.97 mg·g-1.在种间水平上,青海云杉叶片氮、磷含量明显低于全球松科其它针叶树种;在种内水平上,随着海拔的增加,青海云杉叶片氮含量表现出降低的趋势,叶片磷含量变化趋势不明显.叶片氮含量与年均气温呈显著正相关关系(r=0.616**),与土壤水分呈显著负相关关系(r=-0.640**),与土壤有机质、全氮均呈显著负相关关系(r=-0.591**,r=-0.564**);叶片磷含量与年均温、土壤水分之间的关系不显著;叶片氮、磷之间的比率为10.2.表明温度和水分对青海云杉叶片氮、磷含量的影响主要是通过影响土壤生物化学过程(如养分有效性、根系对养分的吸收等)来实现的,青海云杉生长更多的受到氮素限制.
The contents of nitrogen and phosphorus in leaves of Picea crassifolia were measured in the northern slope of Qilian Mountains in September 2005. The results showed that the average contents of nitrogen and phosphorus in P. spruce were 9.75 and 0.97 mg · g-1, respectively. At the interspecific level, the contents of nitrogen and phosphorus in the spruce leaves of Qinghai were obviously lower than those of other coniferous species in the world. With the elevation increasing, the nitrogen content of P. spruce leaves showed a decreasing trend, There was a significant positive correlation between leaf nitrogen content and annual mean temperature (r = 0.616 **) and a significant negative correlation with soil moisture (r = -0.640 **) (R = -0.591 **, r = -0.564 **). The relationship between leaf phosphorus content and annual average temperature and soil moisture was insignificant. The ratio of nitrogen to phosphorus in leaf was 10.2 The effects of temperature and water on nitrogen and phosphorus content of P. spruce leaves mainly through the influence of soil biochemical processes (such as nutrient availability, nutrient uptake by roots, etc.), and the growth of Picea crassifolia was more restricted by nitrogen .