畜禽粪便堆肥中新型N2O产生途径及其关联微生物功能群特征研究

批准号：

52070196

项目类别：

面上项目

资助金额：

58.0 万元

负责人：

王成

依托单位：

中山大学

学科分类：

固废资源转化与安全处置

结题年份：

2024

批准年份：

2020

项目状态：

已结题

项目参与者：

王成

关键词：

产生途径微生物堆肥氧化亚氮功能菌群

项目摘要

结项摘要

王成的其他基金

相似基金

相关文献

中文摘要

畜禽粪便堆肥是重要的N2O排放源，主要由微生物驱动的氮循环过程产生。随着畜禽养殖规模不断扩大，N2O排放污染日趋严重，引发了学者们对畜禽粪便堆肥中N2O产生机制的广泛关注。然而，堆体内外环境的高度异质性、氮循环微生物之间复杂的交互作用，使得畜禽粪便堆肥中微生物驱动的N2O产生途径及其机制仍不明确。本项目将对畜禽粪便堆肥生境中多种N2O产生功能菌群进行定向富集，运用稳定同位素示踪和微生物组学方法，探索畜禽粪便堆肥中新型N2O产生途径及其分子标记；然后通过确定的分子标记，解析N2O产生关联微生物功能群在畜禽粪便堆肥中的形成机制和影响因素；最后综合分析微生物群落、N2O排放量和环境因子等数据，应用机器学习法评估各N2O产生途径对畜禽粪便堆肥N2O排放量的贡献。本项目的实施不仅能增强我们对畜禽粪便堆肥中N2O产生与机制的认识，也为保护农业生态环境和缓解全球气候变暖提供科学依据。

英文摘要

Composting of livestock manure is considered as an important source of nitrous oxide (N2O) emissions, which are largely driven by microbes. With the continuous expansion of livestock industry, the N2O emission during the manure composting has become a severe problem, which arises scholars' attention to the mechanism of N2O production during the manure composting. However, due to the high heterogeneity of the internal and external environment of compost piles, and the complex interaction between nitrogen-cycling microorganisms, such microbially-driven N2O production processes and their involved microbial communities have not been well studied during the manure composting. In this study, we will enrich microbial communities from compost samples under six possible N2O-producing conditions and isolate key functional microbes to identify molecular biomarkers (key functional microbes or/and genes) involved in each N2O-producing process, and understand their microbial mechanisms through stable isotope probing and microbiome assays. Again, we will adopt those identified biomarkers (traditionally used and newly discovered) to analyze representative samples from the manure composting process, and understand mechanisms for N2O-producing microbial community assembly as well as their relationships with environmental factors during the manure composting. Finally, we will integrate microbial, N2O emission and environmental data, to evaluate the contribution of each N2O-producing process to the N2O emissions during the manure composting by machine learning approach. This proposed study will not only strength our understanding of N2O-producing processes and their microbial mechanisms during the manure composting, but will also provide novel scientific evidence for protecting agricultural environments and mitigating global change effects.

畜禽粪便堆肥是重要的N2O排放源，其排放机制主要由微生物驱动的氮循环过程控制。随着畜禽养殖规模扩大，N2O排放污染日趋严重，然而堆体内外环境的高度异质性和氮循环微生物间复杂的交互作用，使得其产生机制仍不明确。本项目通过设置牛粪、羊粪、猪粪和鸡粪4种堆体系统，运用富集培养、宏基因组和宏转录组测序技术，系统解析了N2O产生关联微生物功能群的时空演替规律及其调控机制。研究发现，反硝化过程是牛粪、羊粪和猪粪堆体中最主要的N2O产生途径，而鸡粪堆体则呈现从DNRA过程为主向反硝化过程为主的演变特征。DNRA过程对N2O产生的贡献显著，其相关基因表达量占比达21.2-33.1%，为进一步验证DNRA途径的普遍性，本研究分析了来自29个堆肥堆体的174个宏基因组测序数据集，涵盖5种不同堆肥材料。结果表明，DNRA和DNRA+HD途径相关的norB基因丰度不仅存在于研究的畜禽粪便中，在人类粪便和污泥堆肥过程中也有显著表现。在堆肥管理策略研究中发现，超高温条件显著提高了与DNRA和DNRA+HD途径相关的norB基因丰度（p < 0.001）。特别是在静态超高温堆肥系统中，DNRA相关基因表达量最高可达41±6.4%。时间序列分析显示，DNRA+HD途径相关的norB基因丰度在降温阶段显著高于升温阶段（p = 0.043）。本研究首次揭示了DNRA途径在畜禽粪便堆肥N2O产生中的重要贡献，并在更广泛的堆肥系统中得到验证。同时阐明了不同堆肥系统中N2O产生的微生物调控网络及其受环境因子的影响规律，为制定精准的N2O减排策略提供了理论依据。课题相关的研究成果在Environmental Science & Technology、The ISME Journal 、Soil Biology and Biochemistry和Journal of Hazardous Materials等国际知名学术期刊发表研究论文5篇，投稿SCI论文2篇；培养博士研究生2名，硕士研究生1名。按计划较好地完成了项目设置的各项考核指标。研究结果对于保护农业生态环境和应对全球气候变化具有重要的科学意义。