Institute of Water Resources and Environment, Jilin University, Changchun, 130021, China.
College of Construction Engineering, Jilin University, Changchun, 130026, China.
Environ Geochem Health. 2018 Jun;40(3):1051-1066. doi: 10.1007/s10653-017-9975-9. Epub 2017 May 13.
As one of the important elements of controlling the redox system within the hyporheic and hypolentic zone, sulfur is involved in a series of complex biogeochemical processes such as carbon cycle, water acidification, formation of iron and manganese minerals, redox processes of trace metal elements and a series of important ecological processes. Previous studies on biogeochemistry of the hyporheic and hypolentic zones mostly concentrated on nutrients of nitrogen and phosphorus, heavy metals and other pollutants. Systematic study of biogeochemical behavior of sulfur and its main controlling factors within the lake hypolentic zone is very urgent and important. In this paper, a typical desert plateau lake, Dakebo Lake in northwestern China, was taken for example within which redox zonation and biogeochemical characteristics of sulfur affected by hydrodynamic conditions were studied based on not only traditional hydrochemical analysis, but also environmental isotope evidence. In the lake hypolentic zone of the study area, due to the different hydrodynamic conditions, vertical profile of sulfur species and environmental parameters differ at the two sites of the lake (western side and center). Reduction of sulfate, deposition and oxidation of sulfide, dissolution and precipitation of sulfur-bearing minerals occurred are responded well to Eh, dissolved oxygen, pH, organic carbon and microorganism according to which the lake hypolentic zone can be divided into reduced zone containing HS, reduced zone containing no HS, transition zone and oxidized zone. The results of this study provide valuable insights for understanding sulfur conversion processes and sulfur biogeochemical zonation within a lake hypolentic zone in an extreme plateau arid environment and for protecting the lake-wetland ecosystem in arid and semiarid regions.
作为控制底层和底层区氧化还原系统的重要因素之一，硫参与了一系列复杂的生物地球化学过程，如碳循环、水酸化、铁锰矿物的形成、痕量金属元素的氧化还原过程以及一系列重要的生态过程。以前对底层和底层区生物地球化学的研究主要集中在氮和磷、重金属和其他污染物等营养物质上。系统研究硫在湖底层区的生物地球化学行为及其主要控制因素非常紧迫和重要。本文以中国西北部的大科泊湖为例，对受水动力条件影响的底层区硫的氧化还原分带和生物地球化学特征进行了研究，不仅采用了传统的水化学分析方法，还利用了环境同位素证据。在研究区的湖底层区，由于水动力条件的不同，两个湖点（西侧和中心）的硫物种和环境参数的垂直分布存在差异。硫酸盐的还原、硫化物的沉积和氧化、含硫矿物的溶解和沉淀与 Eh、溶解氧、pH 值、有机碳和微生物密切相关，据此可将湖底层区分为含有 HS 的还原区、不含有 HS 的还原区、过渡区和氧化区。本研究结果为理解极端高原干旱环境下湖泊底层区硫的转化过程和硫的生物地球化学分带以及保护干旱和半干旱地区的湖泊湿地生态系统提供了有价值的见解。
