毛竹林土壤微生物对凋落物硅素循环的影响及其机制研究

凋落物降解是森林生态系统中养分归还的主要方式，森林每年从土壤中吸收的养分中69~87%以凋落物形式返还土壤。作为典型的Si超富集禾本科植物，凋落物降解对毛竹林硅素循环具有重要意义。本项目针对凋落物降解参与竹林硅循环过程，以土壤微生物活动为中心，通过野外调查和林间原位培养相结合的研究方法，应用不同种类的森林凋落物（竹子、阔叶树、针叶树及混合物），研究不同森林凋落物降解过程中土壤有效硅的变化特征，采用现代微生物学与分子生物学等技术（例如原位培养、MiSeq高通量测序等），研究竹林土壤微生物群落结构及活性对凋落物降解的影响，探讨土壤有效硅动态与土壤功能微生物的相互关系，揭示不同凋落物降解生成土壤有效硅的的微生物生态学规律，以期增加人们对土壤微生物参与竹林硅的生物地球化学循环的理解。

Litter is the main channel of nutrient return in forest ecosystems, and the amount of nutrient return presented about 68-87% nutrient uptake from soil of forestry. As a typical gramineous plant with silicon hyperaccumulation, decomposition of litter is important in order to the silicate cycling in the subtropical bamboo forest ecosystem. At the centre of microbial activities, the major subjects aim at the processes of decomposition of litter participating in the silica cycling, which combining field investigation and culture in situ. The research will examine the changes of available silicon in soil of the degradation processes of different forest litters. Through modern microbiology and molecular biology methods, such as culture in situ, MiSeq high-throughput sequencing, etc., studies on the effects of the soil microorganism communities and activities on decomposition of litter will be studied. Furthermore, interactions between the dynamic of the soil available silica and soil function microorganism will be investigated, and the law of the microorganism ecosystem about the soil available silica degraded by different litters will also be revealed. All the above results will increase people's understanding of silicon biogeochemical cycles with participation of soil microbial in the bamboo forest ecosystem.