Erik Jeppesen

TY - JOUR

T1 - Macrophytes and periphyton carbon subsidies to bacterioplankton and zooplankton in a shallow eutrophic lake in tropical China

AU - de Kluijver, A.

AU - Ning, J.

AU - Liu, Z.

AU - Jeppesen, E.

AU - Gulati, R. D.

AU - Middelburg, J. J.

PY - 2015/3

Y1 - 2015/3

N2 - The subsidy of carbon derived from macrophytes and associated periphyton to bacterioplankton and zooplankton in subtropical shallow eutrophic Huizhou West Lake in China was analyzed using carbon stable isotope signatures. A restored part of the lake dominated by macrophytes was compared with an unrestored phytoplankton-dominated part. Macrophytes, periphyton, seston, and zooplankton were sampled every two months to determine natural-abundance carbon isotope ratios (C-13). The C-13 of phytoplankton and bacterioplankton was determined from C-13 of fatty acid biomarkers. Macrophytes and associated periphyton had similar C-13 values and were the most enriched in C-13 of all measured organic carbon pools. A macrophyte-periphyton carbon isotopic signal was detected in particulate organic carbon, bacterioplankton, and zooplankton in the macrophyte-dominated lake part, which was demonstrated by a significant enrichment in C-13 compared with the unrestored part, while phytoplankton and dissolved organic carbon had similar C-13 values in both lake parts. A two-source (macrophytes-periphyton and phytoplankton) mixing model showed that macrophytes-periphyton potentially contributed 14-85% (average 55%) to bacterioplankton in the macrophyte-dominated lake part, depending on season. The macrophytes-periphyton contribution to zooplankton seasonally varied between 26% and 86%, with an average of 47%. The contribution of macrophytes-periphyton to bacterioplankton increased with increasing macrophyte biomass relative to phytoplankton biomass (indicated by chlorophyll a). Carbon from macrophytes with associated periphyton subsidizes bacterioplankton and zooplankton, likely enhancing the cascading effects of planktonic food webs, providing an additional explanation for the stability of a clear-water state in shallow lakes dominated by macrophytes.

AB - The subsidy of carbon derived from macrophytes and associated periphyton to bacterioplankton and zooplankton in subtropical shallow eutrophic Huizhou West Lake in China was analyzed using carbon stable isotope signatures. A restored part of the lake dominated by macrophytes was compared with an unrestored phytoplankton-dominated part. Macrophytes, periphyton, seston, and zooplankton were sampled every two months to determine natural-abundance carbon isotope ratios (C-13). The C-13 of phytoplankton and bacterioplankton was determined from C-13 of fatty acid biomarkers. Macrophytes and associated periphyton had similar C-13 values and were the most enriched in C-13 of all measured organic carbon pools. A macrophyte-periphyton carbon isotopic signal was detected in particulate organic carbon, bacterioplankton, and zooplankton in the macrophyte-dominated lake part, which was demonstrated by a significant enrichment in C-13 compared with the unrestored part, while phytoplankton and dissolved organic carbon had similar C-13 values in both lake parts. A two-source (macrophytes-periphyton and phytoplankton) mixing model showed that macrophytes-periphyton potentially contributed 14-85% (average 55%) to bacterioplankton in the macrophyte-dominated lake part, depending on season. The macrophytes-periphyton contribution to zooplankton seasonally varied between 26% and 86%, with an average of 47%. The contribution of macrophytes-periphyton to bacterioplankton increased with increasing macrophyte biomass relative to phytoplankton biomass (indicated by chlorophyll a). Carbon from macrophytes with associated periphyton subsidizes bacterioplankton and zooplankton, likely enhancing the cascading effects of planktonic food webs, providing an additional explanation for the stability of a clear-water state in shallow lakes dominated by macrophytes.

KW - DISSOLVED ORGANIC-CARBON

KW - TOP-DOWN CONTROL

KW - STABLE-ISOTOPES

KW - FOOD-WEB

KW - SUBMERGED MACROPHYTES

KW - MARINE ECOSYSTEMS

KW - MESOTROPHIC LAKE

KW - TROPHIC CASCADES

KW - FATTY-ACIDS

KW - FRESH-WATER

U2 - 10.1002/lno.10040

DO - 10.1002/lno.10040

M3 - Journal article

VL - 60

SP - 375

EP - 385

JO - Limnology and Oceanography

JF - Limnology and Oceanography

SN - 0024-3590

IS - 2

ER -