郭岩山不同海拔丝栗栲细根功能性状及其与土壤因子的关系

Functional Characteristics of Castanopsis fargesii Fine Roots and Their Relationship with Soil Factors at Different Elevations in Guoyan Mountain

摘要:

为揭示丝栗栲(Castanopsis fargesii)细根功能性状对环境变化的适应机制，对郭岩山500、700、900 m海拔处丝栗栲细根功能性状及其与土壤因子的关系进行研究。结果表明，丝栗栲细根生物量与细根根长密度、表面积密度、组织密度及体积密度呈正相关，细根根长密度、体积密度、表面积密度和比根长4个性状间均呈极显著正相关关系，且均与细根组织密度呈显著负相关。根际土含水量、C和N含量与细根比根长、根长密度、体积密度、表面积密度均存在显著正相关关系，而土壤容重与细根组织密度呈正相关。海拔700 m的细根生物量、根长密度、表面积密度及体积密度显著大于海拔500和900 m的。500和900 m海拔的根长密度、表面积密度与土壤深度呈负相关，而500 m海拔细根的组织密度与土壤深度呈正相关。因此，郭岩山丝栗栲通过改变细根功能性状来适应海拔和土壤的变化。

Abstract:

In order to reveal the adaptation mechanism of fine root functional characters of Castanopsis fargesii to environmental changes, the relationship between functional traits of fine roots and soil factors of C. fargesii at 500, 700 and 900 m altitude in Guoyanshan was studied. The results showed that the fine root biomass was positively correlated with fine root length density, surface area density, tissue density and volume density. Fine root length density, volume density, surface area density and specific root length had significantly positive correlations each other, and which had significantly negative correlations with fine root tissue density. The contents of rhizosphere soil water, C and N had significant positive correlation with fine root specific root length, root length density, bulk density and surface area density, while those had positive correlation with soil bulk density and fine root tissue density. The fine root biomass, root length density, surface area density and volume density at altitude 700 m were significantly higher than those at 500 and 900 m. The root length density and surface area density were negatively correlated with soil depth at altitude 500 and 900 m; while the tissue density of fine roots at 500 m altitude was positively correlated with soil depth. Therefore, Castanopsis fargesii in Guoyanshan could change its fine root function traits in order to adapt to the changes in altitude and soil.