枸杞枝条基质化发酵氮素转化特征及微生物协同调控机制

Ningxia's typical residue –the pruning branches of wolfberry is taken as the object of this research.Such methods as 15N isotope tracing method, enzymology, high-throughput sequencing with the conventional dilution plate culture are used to study the physicochemical properties, nitrogen transformation and its response to C/N changes during the Wolfberry Branches Fermentation for improving the situation in Northwest China such as the demand for horticultural substrates in non-cultivated land，the surge of Agro-forestry Residue and aggravating pollution of agricultural non-point source. Through this study the structure and diversity of microbial communities, species abundance, homogeneity, and species distribution in the process of nitrogen transformation in fermented compost are defined and the characteristic of carbon and nitrogen conversion during the fermentation process of twig flour and the response of key enzyme are revealed. This study has an in-depth discussion about characteristics of nitrogen transformation and biological processes regulated by nitrogen during fermentation of litchi stalks for reducing nitrogen volatilization to maximize nitrogen availability of substrate. Besides, this study can provide a theoretical basis for utilization of wolfberry branches that made to be horticultural substrates. This project has important research value and practical significance in solving the pollution of agro-forestry residue and developing new horticultural substrates. Two or three theses need to be published, one or two of which should be SCI or EI.

针对西北非耕地设施园艺基质需求量和农林废弃物激增、农业面源污染加剧等问题，以宁夏典型废弃物--枸杞修剪枝条作为研究对象，采用15N同位素示踪法、酶学、高通量测序技术与常规稀释平板培养法相结合等分析手段，研究枸杞枝条基质发酵过程中堆体理化性状、氮素转化及其对C/N变化的响应规律，明确发酵堆体氮素转化过程中微生物群落结构和多样性、种的丰度、均度以及种的分布，揭示枝条粉堆体发酵过程中碳氮转化特征及与关键酶变化响应规律，分析微生物群落多样性及酶活性与氮素形态组分和氮素有效性变化间的关系，深入探讨枸杞枝条基质发酵过程中氮素转化特征及氮素调控的生物学过程，减少氮素挥发，最大限度保持基质氮素有效性，最终为枸杞枝条基质化利用提供理论依据。项目对解决农林废弃物污染、开发新型园艺基质具有重要的研究价值和现实意义。发表学术论文2~3篇，其中SCI、EI论文1~2篇。

“枸杞枝条基质化发酵氮素转化特征及微生物协同调控机制(31860576)”项目严格按照国家自然科学基金委员会资助项目计划书，针对西北非耕地设施园艺基质需求量和农林废弃物激增、农业面源污染加剧等问题，以宁夏典型废弃物--枸杞修剪枝条作为研究对象，采用酶学、高通量测序技术与常规稀释平板培养法相结合等分析手段，研究了枸杞枝条基质发酵过程中堆体理化性状、氮素转化及其对C/N变化的响应规律，C/N在25-30，为氨化作用临界区间，C/N在35-43，为反硝化作用临界区间，C/N25，为硝化作用临界值。项目明确了发酵堆体氮素转化过程中微生物群落结构和多样性、种的丰度、均度以及种的分布，揭示了枝条粉堆体发酵过程中碳氮转化特征及与关键酶变化响应规律，分析了微生物群落多样性及酶活性与氮素变化的关系，优势细菌群落为变形菌门（Proteobacteria）、拟杆菌门（Bacteroidetes）、浮霉菌门（Planctomycetes）、疣微菌门（Verrucomicrobiota）、芽单胞菌门（Gemmatimonadetes）和脱硫杆菌门（Desulfobacterota），优势细菌群落为子囊菌门（Ascomycota）、担子菌门（Basidimycota）和隐秘菌门（Cryptomycota）。解析了外源物质添加对枸杞枝条基质发酵过程中氮素转化特征及氮素调控的生物学过程，由于协同效应的存在，生物炭与脱硫石膏结合可以调节微生物的分解代谢谱，其既能提高氮的利用率，又能减少氮的损失，最大限度保持基质氮素有效性，最终为枸杞枝条基质化利用提供理论依据。项目对解决农林废弃物污染、开发新型园艺基质具有重要的研究价值和现实意义。完成了各项目标任务，达到了预期研究目标。