黄土高原狼牙刺丛枝菌根与球囊霉素的空间分布

Spatial distribution of arbuscular mycorrhizal and glomalin in the rhizosphere of Sophora davidii on the Loess Plateau

【目的】探讨黄土高原丛枝菌根真菌（AMF）及球囊霉素与土壤因子的关系及其在生态恢复中的作用。【方法】在陕西黄土高原的志丹、安塞、延长、陇县、淳化和韩城6县（市）选取6个样地,采集5~30 cm土层狼牙刺（Sophora davidii）根系和土壤,测定土壤养分含量、酶活性以及AMF侵染率、孢子密度等,研究狼牙刺根际AMF侵染率、孢子密度和球囊霉素与土壤因子之间的关系。【结果】AMF平均侵染率达74.42%,孢子密度均值达19.06个/g,AMF侵染率和孢子密度在各样地间差异显著,但是两者无显著相关性。土壤中总球囊霉素平均含量为2.32mg/g,占土壤有机碳的36.46%,球囊霉素含量和孢子密度均表现出明显的空间异质性。球囊霉素含量与有机碳、碱解氮和速效磷含量呈极显著正相关（P〈0.01）,与土壤pH呈负相关。同时,球囊霉素含量还与蔗糖酶、脲酶、碱性磷酸酶和过氧化氢酶活性呈显著相关。【结论】AMF和球囊霉素含量与土壤养分、酶活性等显著相关,可作为黄土高原生态系统环境状况检测的有效指标。

【Objective】 The research was conducted to explore the relationship between soil factors and arbuscular mycorrhizal and glomalin.【Method】 Six sampling plots were chosen on the Loess Plateau in Shaanxi.Soil sampling（5-30 cm depths） in the rhizosphere of Sophora davidii was collected using five points sampling method.The spatial distribution of mycorrhizae colonization,spore density and glomalin in the rhizosphere of S.davidii and their relationships with soil factors were investigated on the Loess Plateau.【Result】 AMF colonization was up to 74.42% on average,the spore density averaged 19.06 per gram soil and the regional difference was significant,but the rate of AMF colonization was not correlated significantly with the spore density.The mean of glomalin total was 2.32 mg/g,accounting for 36.46% of soil organic carbon.The distribution of spore density and glomalin presented spatial heterogeneity.Glomalin was related with soil organic carbon,available N and Olsen P（P0.01）,and negatively correlated with pH.Meanwhile,it was remarkably correlated with soil enzyme activities.【Conclusion】 Our results showed that the soil factors were strongly correlated to AM fungi,and the AMF spore density and glomalin were useful indicators for the building and perfecting of index evaluation system.