水体溶解性有机物的性质特征、分析手段与环境效应

PROPERTIES,CHARACTERIZATION METHODS,AND ENVIRONMENTAL IMPACTS OF DISSOLVED ORGANIC MATTER IN AQUATIC SYSTEMS

溶解性有机物(DOM)在自然界的水环境中广泛存在,是水相有机物的主要组成部分。DOM表现出复杂的环境与生态反馈功能,与微生物的生长代谢有着紧密关系。在循环的自然生态过程中,河流是各种源汇的输送体,海洋成为最终的受纳体,统计分析了水体DOM在废水-污水-河流/湖泊-海洋环境中的性质和分布,指出DOM发挥着生物初级生产力、能量提供、光合效应、化学调控、微量金属传输、碳汇等方面的功能,并最终影响人类健康的观点。DOM的组成复杂,包括多糖、蛋白质、腐殖质、脂质和小分子有机酸等。自然途径通过大分子有机物的腐烂降解、动物及微生物的新陈代谢、植物根系的分泌物和植物生长衰亡过程,这些途径受地理-环境-气候等因素的影响;人为途径向水源中引入DOM不可忽视,其中,大部分来自污废水处理排放尾水中的残余有机污染物。DOM的转化与归趋影响着自来水厂的出水水质和天然水体中的微生物群落结构,因此,对DOM的定性定量分析十分重要。对此,系统介绍了DOM的分析原理、应用对象与技术特征,并提出发展测量技术、识别表征、生成机制、多相化学以及生态健康等方面的联用与瞬态技术的社会需求。最后,通过自然水体、城市污水、工业废水、厌氧发酵与渗滤液等来源,分析讨论了DOM浓度梯度的环境影响,强调元素水平的生态可持续发展与平衡机制的学术意义,认为DOM的元素驱动机制、生态调控机制以及信息通量分析成为未来该领域研究的重要方向。

Dissolved organic matter(DOM)pervades natural aquatic environments as the primary constituent of aqueous organic matter.It plays intricate roles in environmental and ecological feedback mechanisms,closely linked to the growth and metabolism of microorganisms.In the natural ecological cycle,rivers function as conveyors for various sources and sinks,with the ocean serving as the ultimate receptor.This paper employs statistical analysis to summarize the nature and distribution of DOM across water bodies in wastewater-sewage-river/lake-ocean environments,highlighting the various functional aspects of DOM,including biological primary productivity,energy supply,photosynthetic effect,chemical regulation,trace metal transport,carbon sink,and its impact on human health.DOM has a complex composition,comprising polysaccharides,proteins,humus,lipids,small molecular organic acids,etc.The natural pathways for DOM formation involve the degradation of macromolecular organic matter,animal and microbial metabolism,plant root secretion,and the decline process of plant growth.These pathways are influenced by geographic,environmental,and climatic factors.Human-induced introduction of DOM into water sources,particularly sourced from residual organic pollutants in wastewater treatment plant effluents,also should not be overlooked.The transformation and fate of DOM have significant effects on both the effluent quality of drinking water plants and the microbial community structure in natural water bodies.Therefore,accurate and comprehensive qualitative and quantitative analysis of DOM is imperative.In this regard,this paper systematically outlines the analysis principles,application objects,and technical characteristics of DOM studies,and proposes the necessity to develop collaborative and dynamic analytical methodologies in measurement technology,identification and characterization,generation mechanism,multiphase chemistry,and ecological health analysis.Last but not least,the environmental impact of the DOM concentration gradient is discussed through the comparison of various sources such as natural water bodies,urban sewage,industrial wastewater,anaerobic fermentation,and leachate,emphasizing the scientific significance of ecological sustainability and balance mechanisms at the elemental level.This paper endeavors to propose that ongoing research should focus on the elemental driving mechanisms of DOM,ecological regulatory mechanisms,and information flux analysis.