Application of subfossil Bosmina and its δ13C values in tracing the long-term food web dynamics of shallow eutrophic lakes: A case in Taihu Lake, southeast China

Longjuan Cheng; Giri Kattel; Bin Xue; Shuchun Yao; Lingling Li; Jinliang Liu

doi:10.1016/j.scitotenv.2020.138909

Application of subfossil Bosmina and its δ¹³C values in tracing the long-term food web dynamics of shallow eutrophic lakes: A case in Taihu Lake, southeast China

Sci Total Environ. 2020 Aug 15:730:138909. doi: 10.1016/j.scitotenv.2020.138909. Epub 2020 Apr 23.

Authors

Longjuan Cheng¹, Giri Kattel², Bin Xue³, Shuchun Yao⁴, Lingling Li¹, Jinliang Liu¹

Affiliations

¹ State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Shijingshan District (A), Beijing 100049, China.
² State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; Department of Infrastructure Engineering, University of Melbourne, Victoria 3010, Australia; Department of Hydraulic Engineering, Tsinghua University, Beijing 100084, China.
³ State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China. Electronic address: bxue@niglas.ac.cn.
⁴ State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China.

PMID: 32388368
DOI: 10.1016/j.scitotenv.2020.138909

Abstract

Cladoceran subfossil assemblages have been used successfully to trace the signals of long-term changes in lake eutrophication. However, their potential for reconstructing food webs has not yet been explored extensively. Here, we assess whether the stable carbon isotope analysis (SCIA) of subfossil Bosmina can be used to reconstruct the eutrophication and food web history of a shallow lake in southeast China. Two ²¹⁰Pb-dated sediment cores were collected from the western and central parts of Taihu Lake, one of the largest eutrophic lakes in the region. Multiproxy analyses of the cores were performed, including of the subfossil Bosmina assemblages, stable carbon isotopes of subfossil Bosmina (δ¹³C_s-bos) and bulk sediment (δ¹³C_org), total organic carbon (TOC), loss on ignition (LOI), C/N, total nitrogen (TN), and total phosphorous (TP). Stable carbon isotopes of living algae (δ¹³C_alg) and Bosmina (δ¹³C_l-bos) were also measured at the same sampling locations. The δ¹³C_s-bos gradually declined over time with reciprocal increases in the assemblages of subfossil Bosmina and total cladocerans and in the TOC, LOI, TN and TP in both cores. The δ¹³C_alg and δ¹³C_l-bos values further revealed depleted ¹³C. The changes in the δ¹³C_s-bos in relation to the other proxies indicated rapid nutrient enrichment and a possible shift in the food web in Taihu Lake, providing new insight into the reconstruction of food webs and eutrophication in shallow lakes in southeast China.

Keywords: Bosmina; Eutrophication; Food web; Southeast China; Stable carbon isotope; Taihu Lake.

MeSH terms

China
Environmental Monitoring
Eutrophication
Food Chain*
Lakes*
Phosphorus

Substances

Phosphorus