淡水体系中透明胞外聚合颗粒物(TEP)的研究进展

Advances in Ttransparent Exopolymer Particles( TEP) in Freshwaters

透明胞外聚合颗粒物(Transparent Exopolymer Particles,TEP)是水体中一类特殊的自由形态胞外聚合物(Extracellular Polymeric Substances,EPS),同时具有固相胶体相两相特点以及低密度、高碳氮比、高黏性等特点,因而对水体生态系统中的地球化学循环产生重要的作用。通过对国内外文献的查阅及太湖的调查研究,概述了国内外对于TEP研究的现状与动态。对其来源及形成,包括丰度分布、数量及生态意义进行综述。需要指出的是,尽管目前已经有许多关于海洋中TEP特性的研究,但是,对于淡水湖泊中TEP的研究仍然非常稀少。说明TEP在营养元素的地球化学循环过程中的作用及其重要性并没有得到充分的认识。未来的研究方向应该侧重淡水生态体系中TEP的来源及其形成机制方面,特别是与EPS库的其他形态之间的相互转化关系及与微生物、浮游植物(包括与水华暴发蓝藻)新陈代谢之间的关联机制,和TEP的降解、归趋及循环,以及对水体生态系统的影响等方面。此外,饮用水或污水处理中TEP对处理工艺的影响需得到重视。

Transparent Exopolymer Particles （TEP） represent one specially free form of Extracellular Polymeric Substances （EPS）. They have the characteristics of solid phase and gel phase, low density, high ratio of carbon to nitrogen, and high stickiness. So, they play an important role in the geochemical cycles of aquatic ecosystems. Based on the literature at home and abroad and the investigation of Lake Taihu, we summarized the research status and dynamics of TEP. The origin and form of TEP, the abundance and significance of TEP in freshwaters were summerized. It should be noted that the study of TEP in freshwater lakes was still relatively few, although there were many researches about the charateristics of TEP in oceans. This suggests that the significance and importance of TEP in geochemical cycle of nutrient elements have not been fully understood. The directions for future research should focus on the origin and form mechnisms of TEP in freshwater ecosystems, especially on the relatioship between TEP and the other forms in EPS pool, the correlative mechanism between TEP and the microorganism and phytoplankton （ including blooming-cyanobacteria）, the degradation, the fate and cycling of TEP, and the impact of TEP on aquatic ecosystems. Besides, the impact of TEP on the water treatments should be also given attention.