用链烷技术研究土壤与植被原生关系

Study the relationships between the soil and the original vegetation using n-alkane technique

采用链烷技术研究河北坝上地区退化草地土壤的饱和链烷相对浓度模式,与未退化草地优势种的饱和链烷相对浓度模式对比,探究土壤与植被的原生关系。发现芨芨草Achnatherumsplendens样地、马蔺Iris lacteal样地、鼠洞样地和狼毒Stellera chamaejasme样地的土壤链烷相对浓度模式与羊草Leymuschinensis的链烷相对浓度模式相匹配,推测这4种退化草地的原生植被与当前未退化样地植被相似;冷蒿Artemisia frigida样地与羊草的链烷相对浓度模式匹配较差,与冷蒿的链烷相对浓度模式匹配较好,说明土壤的链烷相对浓度模式的变化可以反应出地上植被的变化情况。土壤链烷来自植物的根、枯落物和种子,土壤链烷相对浓度模式的稳定存在,说明相对于植被退化,土壤退化有滞后性。

The n-alkane technique was used to study the n-alkane concentrations in soil of degraded grassland in Bashang area of Hebei Province. The n-alkane concentrations were contrasted with dominant species in un-degraded grassland to explore the relationships between the soil and the original vegetation. The result showed that the n-alkane concentration in soil of Achnatherum splendens plot, sword iris plot, mouse damaged plot and Stellera chamaejasme plot matched well with the n-alkane concentration of Leymus chinensis, it could be presumed that the original vegetation of these degraded grasslands was similar with un-degraded grassland. The n-alkane concentration in soil in Artemisia frigida plot matched poor with the n-alkane concentrations of L. chinensis and matched well with that of A. frigida, and it suggested that the change of n-alkane concentration could reflect the vegetation change. The n-alkane concentration was stable in soil and it suggested that the processes of soil degradation lagged behind the vegetation degradation.