球囊霉素对维持土壤有机碳平衡和土壤团聚体稳定性具有明显作用, 但不同土地利用方式下土壤球囊霉素的土层分布模式及其影响因素尚不清楚。本研究选取农田、人工草地、果园和撂荒地4种不同土地利用方式, 分别采集0~10 cm、10~20 cm、20~30 cm和30~40 cm 4个土层土样, 通过测定土壤球囊霉素、pH、速效磷、有机碳和蛋白酶活性, 研究不同土地利用方式下土壤球囊霉素土层分布的模式及影响因素。结果表明, 土壤球囊霉素平均含量为1.41~3.18 mg·g-1, 占土壤有机碳的6.98%~31.34%, 是土壤中的一个重要碳库。土壤球囊霉素在不同土地利用方式和土层剖面之间表现出显著差异(P<0.01), 具有明显的垂直分布特征, 除撂荒地外, 其随土层深度的增加表现出降低趋势。土壤球囊霉素分别与土壤速效磷、蛋白酶呈显著正相关(P<0.01)。土壤速效磷在很大程度上决定土壤球囊霉素的含量和分布。土壤球囊霉素含量和土壤蛋白酶活性之间为间接相关关系, 该关系有待于进一步研究。建议把球囊霉素作为研究丛枝菌根真菌生长状况和土壤生态系统波动的一个重要指标。
Despite evident importance of glomalin in maintaining soil organic carbon balance and soil aggregate stability, little remains known about soil profile distribution patterns and influencing factors of glomalin under different land use types. In this study, we selected four land use types (farmland, artificial grassland, orchard and abandoned land) to examine soil profile distribution patterns and influencing factors of glomalin. Soil samples were collected from depths of 0~10 cm, 10~20 cm, 20~30 cm and 30~40 cm respectively. Soil glomalin, pH, available phosphorus, organic carbon and protease activity were determined for the collected soil samples. The results show that average soil glomalin content ranges from 1.41~3.18 mg·g-1, accounting for 6.98%~31.34% of soil organic carbon. Glomalin is therefore regarded as a major carbon pool in soil. Significant differences in soil glomalin are observed among the land use types and soil layers (P< 0.01). Soil glomalin exhibits obvious vertical distribution pattern, which decreases with increasing soil depth (except for abandoned lands). Soil glomalin is significantly directly related with soil available phosphorus and protease (P< 0.01). Soil available phosphorus, to a large degree, determines the content and distribution of soil glomalin. A simple and indirect correlation is observed between soil glomalin and protease. However, more research is recommended to further clarify the relationship. Based on the study, we conclude that glomalin is an important indicator for arbuscular mycorrhizal hyphal growth and variations in soil ecosystem.