锰矿开采引起的锰等重金属污染已造成矿区生态系统的退化。由于主要森林树木的生长和生存依赖于外生菌根菌的互惠共生关系，外生菌根菌群落对锰污染的生态响应也将影响到矿区森林生态系统的稳定和重建。本研究拟采用马尾松幼苗检测法，获取锰矿污染区及无污染区外生菌根菌群落，对其进行锰胁迫试验，研究菌根群落和马尾松幼苗对锰胁迫的响应规律及其在群落间的差异；同时分离优势菌株并鉴定其与马尾松共生苗的锰耐性，以期研究菌根耐锰性与锰胁迫引起的菌根群落结构变化规律的关系。此外，通过测定植株生物量以及氮、磷和锰的含量，利用透射电镜耦合能谱仪测定菌根中锰元素的亚细胞定位，阐明菌根促进马尾松抵御锰毒害的生理机制。通过本研究，旨在揭示外生菌根菌群落对锰污染的适应机制，并筛选出能显著提高马尾松抵御锰毒害的外生菌根菌株，为利用耐锰外生菌根菌强化植物修复锰矿区废弃地提供技术支持和理论依据。

Manganese (Mn) mine activities have caused severe ecological and environmental problems. Because the growth and survival of major tree species largely depend on ectomycorrhizal fungi, the ecological responses of ectomycorrhizal fungi to higher soil Mn could affect the establishment and survival of trees under Mn stresses. In this study, a Seedling Bioassay method will be used to hook the ectomycorrhizal fungal communities associated with Masson pine (Pinus massoniana Lamb.) from the Xiangtan Mn mine wasteland and an adjacent unpolluted forest land. Mn stress experiment will be carreied out on these seedlings in greenhouse by addition of MnSO4 solution. The change patterns of the two typles of ectomycorrhizal communities response to different level of Mn addition will be revealed. The seeldings performance will be also analyzed. Those dominant ectomycorrhizal fungal species prefer to high or low Mn conditions will be isolated, and its difference in Mn-tolerance under symbiotic conditions with Masson pine will be determined. In addition, seedling biomass, nitrogen, phosphorus and Mn contents in shoots and roots will be determined, respectively. The distribution pattern of Mn element in ectomycorrhizal root tips will be analyzed by Transmission Electron Microscopy with X-ray microanalysis, to elucidate the mechanism of the ectomycorrhizal symbiosis modulating Mn uptake of host plant. Taken together, we will reveal the ecological mechanism of the ectomycorrhizal fungal community in response to Mn pollution, and then screen out the Mn-tolerance ectomycorrhizal fungal species/isolates, which will contribute to ecological restoration and phytoremediation of Mn mine wastelands using ectomycorrhizal stragtegy.