农村型黑臭水体形成的硫循环关键功能微生物及其与碳、氮、铁循环功能微生物间的互作关系研究

有别于城市黑臭水体的高COD、氨氮等特点，农村黑臭水体增加了由化肥施用引起的高硫酸盐显著特征。前期研究表明，城市型黑臭水体形成是以硫循环功能菌群丰度的增加为核心；而农村型黑臭水体形成是以硫循环功能菌群相对丰度的改变为核心，且农村型黑臭水体中微生物间的互作关系更为复杂。硫酸根离子对农村型黑臭水体中硫循环微生物产生怎样的影响？在农村黑臭水体中发挥作用的硫循环功能微生物关键物种是谁？硫循环与C、N、Fe循环功能微生物间的群落-功能耦合及互作关系如何？基于以上科学问题，本研究将以海河流域典型农村河流系统为研究目标，基于DNA/RNA-SIP、高通量测序、qPCR等分子生物学技术手段，靶定硫循环关键功能微生物种群，探明高浓度硫酸根离子介导的硫循环功能微生物菌群变化及其与C、N、Fe等元素循环功能微生物间的互作关系。本项目的科学意义是为水圈微生物群落形成及其与环境互作的机理提供一定的理论基础。

Black and odorous water (BOW) has a severe impact on daily life, especially in developing countries like China. BOW in the regions polluted by human urban activities (RU) is characterized with high levels of COD and ammonia, while BOW in the regions polluted by human agricultural activities (RA) is characterized with high levels of sulfate introduced from chemical fertilizer. Previous study showed that the abundance of sulfur cycling genes (dsrB and soxB) were significantly elevated in RU, and the ratio of abundance of dsrB to soxB was significantly elevated in RA compared with those in the protected regions (RP). These results indicated that the formation mechanisms of BOW differed between RU and RA. Meanwhile, the interactions between sulfur cycling microorganisms and the functional microorganisms involved in carbon and metal cycling was more complex in RA compared with that in RP. However, how the sulfur cycling microorganisms are influence by high levels of sulfate? Who are the key sulfur cycling microorganisms for the formation of BOW in RA? How the sulfur cycling microorganisms interacted with the functional microorganisms involved in carbon nitrogen and iron cycling and the coupling mechanisms of community and function? Based on these scientific issues, this program intended to screen the key sulfur cycling microorganisms and classify the interactions between sulfur cycling microorganisms and the functional microorganisms involved in carbon, nitrogen and iron cycling in BOW in RA by using molecular biology methods, such as DNA/RNA-SIP, metagenome sequencing and qPCR. This program will help clarify the mechanisms of the formation of hydrosphere microbial community and the interactions with environmental factors.