青海湖北岸退化与封育草地土壤与优势植物中四种微量元素特征

为了研究退化、封育草地中植物形态与铜、锌、铁、锰等微量元素特征,选择青海湖北岸退化草地为试验样地,以围栏封育草地为对照,通过各类型草地样方调查以及典型植物中铜、锌、铁、锰等微量元素的对比分析,结果表明,退化草地较封育草地植物中铜、锌、铁、锰等微量元素的含量高,且与植物株高、盖度和地上生物量之间具有负相关关系。如:烂泥湾退化草地、封育草地植被中Cu分别为10.480和7.275 mg/kg,而土壤中Cu分别为13.99 和24.19 mg/kg,植物株高则为13.3和17.3 cm;退化草地中植物株高与Cu、Zn之间相关系数为-0.987 3和-0.986 6。退化草地植物中微量元素营养含量的蓄积性既是草地退化的结果,又是退化草地再退化的原因之一,也是其对外界环境变化的一种“应急”响应。

Characteristic of four trace elements in soil and dominant plants form degraded grassland,enclosed grassland on the north bank of Qinghai Lake

In order to study on the relationship between plant shapes and copper, zinc, iron, manganese and other trace elements, so we selected degraded grassland on the north bank of Qinghai Lake as our test sample and fence enclosure as control, through investigated of the types of grass plots and analyzed copper, zinc, iron, manganese and other trace elements in typical plants. The results showed that the contents of copper, zinc, iron, manganese and other trace elements have an accumulation of the plants on degraded grassland compared with that on enclosed grassland, and have a negative correlation between plant shapes-height and ground with biomass. Such as: in Lanniwan, Cu were 10.480 and 7.275 mg/kg in plant form degraded grassland and enclosed grassland, but in soil Cu were 13.99 and 24.19 mg/kg, plant height was 13.3 and 17.3 cm, respectively. In degraded grassland, the correlation coefficient between the plant height and Cu, Zn was -0.987 3 and -0.986 6, respectively. Trace elements nutrient-accumulation in plant form degraded grassland is the result of degraded and also one of the cause grassland accelerated degradation. It is also an “emergency” response for mineral elements nutrition needs change.