Seasonal variation and driving factors of carbon and nitrogen stable isotope values of plankton in four lakes of Yunnan Province

被引：3

作者：

Chen Z. ^{[1
]}

Huang L. ^{[1
]}

Chen L. ^{[1
]}

Liang H. ^{[1
]}

Liu Y. ^{[1
]}

Chen X. ^{[1
]}

Zhang T. ^{[1
]}

Chen G. ^{[1
]}

机构：

[1] Yunnan Key Laboratory of Plateau Geographical Processes and Environmental Change, Faculty of Geography, Yunnan Normal University, Kunming

来源：

Hupo Kexue/Journal of Lake Sciences | 2021年 / 33卷 / 03期

关键词：

Carbon and nitrogen stable isotopes; Lake Fuxian; Lake Yangzong; Phytoplankton; Seasonal fluctuation; Yunnan lakes; Zooplankton;

D O I：

10.18307/2021.0312

中图分类号：

学科分类号：

摘要：

Plankton is an important component of lake food webs. Their carbon and nitrogen stable isotope values can reflect the fluctuation of biogeochemical cycling and food sources and can be applied to track the changes of aquatic ecosystem structure. In this paper, four lakes with distinct typology from Yunnan Province were selected to uncover the seasonal changes in carbon and nitrogen stable isotopic compositions of plankton. The carbon stable isotope values of phytoplankton in large deep lakes (Lake Fuxian and Lake Yangzong) are enriched in summer and autumn (mean ± SD: -20.34‰±1.98‰), but relatively depleted in winter and spring (-28.00‰±2.51‰), which may reflect a higher growth rate of plankton and greater assimilation of bicarbonate (HCO3-) during the growing season. In small shallow lakes (Lake Changqiao and Lake Datun), carbon stable isotopic values of phytoplankton are mostly enriched in summer (-21.24‰±0.88‰) among the four sampling seasons. This may be related to the increased input of terrigenous organic matter during the rainy season, and a decreased lower water level due to overuse of agricultural irrigation in summer. In contrast to the carbon stable isotope values, the nitrogen stable isotope composition of plankton displayed a similar trend of seasonal variations across lakes where a significantly more positive value was found in spring than in other seasons. Further analyses revealed that that seasonal variation in the nitrogen stable isotope of plankton is related to the seasonal difference of nitrogen sources and their distinct isotopic compositions. Specifically, non-point source pollution, mainly related to agricultural fertilizers with depleted nitrogen stable isotopic value, is often dominant in the rainy season, while point source pollution predominantly derived from sewage input with enriched nitrogen stable isotopic composition is commonly observed in the dry season. In terms of stable isotope fractionation between zooplankton and phytoplankton (i.e. trophic enrichment), small shallow lakes were characterized by smaller carbon (1.61‰±0.90‰) and nitrogen (2.71‰±1.22‰) stable isotopic enrichment than those in large deep lakes (2.60‰±0.98‰ and 4.19‰±1.25‰, respectively) in this study. Zooplankton often displays a higher degree of dependence on autochthonous organic carbon (such as phytoplankton) with increasing nutrient status, reflecting a stronger coupling of organic carbon transfer between trophic levels. Similarly, a smaller degree of nitrogen stable isotope enrichment is evidenced in more eutrophic lakes in this study. © 2021 by Journal of Lake Sciences.

引用

页码：761 / 773

页数：12

共 49 条

[1] Lin GH., Stable isotope ecology: A new branch of ecology resulted from technology advances, Chinese Journal of Plant Ecology, 34, 2, pp. 119-122, (2010)
[2] Espinasse B, Pakhomov EA, Hunt B, Et al., Latitudinal gradient consistency in carbon and nitrogen stable isotopes of particulate organic matter in the Southern Ocean, Marine Ecology Progress Series, 631, pp. 19-30, (2019)
[3] Arellano AR, Bianchi TS, Osburn CL, Et al., Mechanisms of organic matter export in estuaries with contrasting carbon sources, Journal of Geophysical Research: Biogeosciences, 124, 10, pp. 3168-3188, (2019)
[4] Chen JG, Yang HQ, Zeng Y, Et al., Combined use of radiocarbon and stable carbon isotope to constrain the sources and cycling of particulate organic carbon in a large freshwater lake, China, Science of the Total Environment, 625, pp. 27-38, (2018)
[5] Gu BH, Chapman AD, Schelske CL., Factors controlling seasonal variations in stable isotope composition of particulate organic matter in a softwater eutrophic lake, Limnology and Oceanography, 51, 6, pp. 2837-2848, (2006)
[6] Peel RA, Hill JM, Taylor GC, Et al., Food web structure and trophic dynamics of a fish community in an ephemeral floodplain lake, Frontiers in Environmental Science, 7, (2019)
[7] Zanden MJV, Rasmussen JB., Variation in δ15N and δ13C trophic fractionation: Implications for aquatic food web studies, Limnology and Oceanography, 46, 8, pp. 2061-2066, (2001)
[8] Hong S, Lee Y, Yoon SJ, Et al., Carbon and nitrogen stable isotope signatures linked to anthropogenic toxic substances pollution in a highly industrialized area of South Korea, Marine Pollution Bulletin, 144, pp. 152-159, (2019)
[9] Wang J, Wu FC, Li W, Et al., Seasonal variation and vertical characteristics of the δ15N of particulate organic matter in Lake Hongfeng and Lake Baihua, Guizhou Province, J Lake Sci, 20, 5, pp. 571-578, (2008)
[10] Griboff J, Wunderlin DA, Horacek M, Et al., δ15N as an indicator of freshwater systems suitable for edible fish production, Ecological Indicators, 108, (2020)

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