红碱淖营养状态及藻类群落演替的近代沉积记录  

Recent sedimentary records of trophic status and algae community succession in Lake Hongjiannao

作　　者：李怡 张含笑 张靖天[1] 马春子[1] 张佩莲 霍守亮[1] LI Yi;ZHANG Hanxiao;ZHANG Jingtian;MA Chunzi;ZHANG Peilian;HUO Shouliang(State Key Laboratory of Environmental Criteria and Risk Assessment,Chinese Research Academy of Environmental Sciences,Beijing 100012)

机构地区：[1]中国环境科学研究院,环境基准与风险评估国家重点实验室,北京100012

出　　处：《环境科学学报》2023年第9期397-406,共10页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金黄河水科学研究联合基金(No.U2243209)。

摘　　要：湖泊沉积物作为流域环境变化的重要信息载体,是揭示历史时期水环境变化及生态系统响应的重要手段,对于湖泊生态系统保护与治理具有重要的科学意义.为解析典型湖泊藻类群落组成结构变化及其驱动机制,采集红碱淖沉积物柱芯样品,以分层沉积物藻类色素和DNA重建藻类群落演替过程并测定营养物指标,运用随机森林模型等统计方法揭示驱动藻类群落演替过程的关键因素.结果表明:(1)沉积物色素保存程度良好、DNA样本量充足,可用于综合反演藻类生物量及群落组成结构变化,红碱淖藻类总体优势类群为耐受高盐碱环境的Chlorellales和Parasynechococcus.(2)CONISS聚类显示真核藻类、蓝藻群落演替可划分为~2010年前后两个阶段,藻类生物量及群落结构均发生显著变化,与湖泊营养状态变化一致.(3)营养物含量与蓝藻物种相对丰度的相关性相较于真核藻类物种更显著.研究显示藻类群落演替与营养状态演变具有相关性,保护红碱淖水生态健康应持续控制氮、磷等外源营养负荷输入.Lake sediment serves as a valuable repository of historical environmental variations,providing crucial insights into aquatic environments and ecosystems Lake sediment serves as an valuable repository of historical environmental variation,providing an important insights to reveal the changes of aquatic environment and ecosystems.It plays a vital role in supporting environmental management and protection.In order to investigate the changes in the composition and structure of algal communities in typical lakes and its driving mechanism,core samples of Lake Hongjiannao were collected to reconstruct the succession process of algal communities by determining algal pigments,DNA,and nutrient indicators.The key variables driving the succession of algal communities were revealed by statistical methods such as random forest model.The results show that:①The sediment pigments and DNA were well preserved,enabling a comprehensive assessment of algal biomass and community composition.The overall dominant algae were Chlorellales and Parasynechococcus,which could tolerate high saline-alkali environment.②CONISS clustering analysis revealed two distinct stages in the succession of eukaryotic algae and cyanobacteria communities,before and after 2010s,with significant changes in the algae biomass and community structure,consistent with the changes in lake trophic status.③The correlation between nutrient content and relative abundance of cyanobacteria species was found to be more significant than that of eukaryotic algae species.considering the connection between algae community succession and the trophic status variation,it is imperative to maintain continuous control over the input of nitrogen,phosphorus and other exogenous nutrients to preserve the ecological health of Lake Hongjiannao.

关 键 词：湖泊沉积物 DNA 色素 藻类 

分 类 号：X523[环境科学与工程—环境工程] X14