拉脊山亚高寒草甸退化程度对土壤养分影响的研究

对亚高寒草甸土壤因素的调查分析,结果表明:全氮和全钾含量随退化程度的加深而减小,依次是轻度退化、中度退化和极度退化。随着草地退化程度的加剧,地上、地下生物量以及土壤全氮、全钾的含量也随之下降。不同退化程度间土壤全磷含量变化不明显,各层次之间虽然有上升趋势,但变化较小。全磷在土壤剖面中分布较均匀,说明退化强度对高山草甸草原土土壤全磷的影响相对较小。高寒草甸生态系统的恶化,不仅使群落物种组成发生了巨大变化,而且导致物种多样性发生改变,这与过度放牧和环境因子的影响程度有着密切的关系。

Research on the Effect of Degradation Degree of Subalpine Meadow on Soil Nutrient in Laji Mountain Area

After investigation and analysis of soil factors of subalpine meadow,the results showed that the content of total N and K decrease with the degradation of grassland,ordered by light degraded meadow,medium degraded meadow,heavily degraded meadow.The aboveground and underground biomass,and total N,total K content decrease with the degradation of grassland.The content of total P in different degradation degrees had no significant change,although there was an ascending tendency,the change was little.Total P distribution in soil section was homogeneous,which indicated that degradation degree had less effect on the total P in soil of subalpine meadow.The deterioration of alpine meadow ecosystem not only changed the species composition a lot,but also made the species diversity changed,which had a close relationship with overgrazing and environmental factors.