He Xue-li, Bai Chun-ming, Zhao Li-li
College of Life Sciences, Hebei University, Baoding 071002, Hebei, China.
Ying Yong Sheng Tai Xue Bao. 2008 Dec;19(12):2711-6.
This paper studied the spatial distribution of arbuscular mycorrhizal (AM) fungi in Astragalus adsurgens root-zone soil in Mu Us sand land under five different ecological conditions. The results showed that the colonization and spore density of AM fungi differed significantly with sampling sites and soil depths. The highest colonization rate and spore density of AM fungi were found in 10-30 cm soil layer, and the highest spore density was at Dingbian site. Ningtiaoliang and Tawan sites had the highest vesicular colonization, and Tawan site had the highest total and hyphal colonization. The contents of total glomalin (TG) and easily extractable glomain (EEG) were the highest at Tawan site, being 1.18 mg x g(-1) and 0.65 mg x g(-1), respectively. Soil pH had significant positive effects on the vesicular and arbuscular colonization, spore density, TG, and EEG, and the TG and EEG had significant positive correlations with spore density, soil organic carbon (SOC), and soil available N and P. The proportion of glomalin to SOC was higher in desert soils than in agricultural soils, which implied that glomalin could be one of the main origins of SOC in desert ecosystem. Therefore, glomalin could be a useful index for the evaluation of soil AM fungal activity and soil ecology.
本文研究了毛乌素沙地5种不同生态条件下沙打旺根际土壤中丛枝菌根（AM）真菌的空间分布。结果表明，AM真菌的定殖率和孢子密度随采样地点和土壤深度的不同而有显著差异。AM真菌定殖率和孢子密度最高的是在10 - 30 cm土层，孢子密度最高的是在定边采样点。柠条梁和塔湾采样点泡囊定殖率最高，塔湾采样点总定殖率和菌丝定殖率最高。塔湾采样点总球囊霉素（TG）和易提取球囊霉素（EEG）含量最高，分别为1.18 mg·g⁻¹和0.65 mg·g⁻¹。土壤pH值对泡囊和丛枝定殖、孢子密度、TG和EEG有显著正效应，TG和EEG与孢子密度、土壤有机碳（SOC）以及土壤有效氮和磷显著正相关。沙漠土壤中球囊霉素占SOC的比例高于农业土壤，这意味着球囊霉素可能是沙漠生态系统中SOC的主要来源之一。因此，球囊霉素可作为评价土壤AM真菌活性和土壤生态的有用指标。
