Comparative study of the vertical distribution characteristics of microplastics and sampling methods for microplastics in the water column: A case study in the Jiulong River estuary

doi:10.3969/j.issn.1000-5641.2024.01.009

Abstract

Abstract:

Due to the influence of tidal processes, sampling and study of microplastics in estuarine areas have been hampered by inconsistent research methods and large data errors. In this study, whole-water depth sampling was conducted in the Jiulong River estuary using the pumping method in August of 2019. The abundances and distribution patterns of microplastics among different water layers and stations were analyzed and compared with research studies performed using different sampling methods. The results showed that the microplastic abundances in the surface, middle, and bottom waters of the Jiulong River estuary were markedly different and influenced by tidal effects. The abundances of microplastics obtained by different sampling methods were also significantly different. The abundance of microplastics in the surface water was significantly higher than the abundances in the middle and bottom waters near the source of pollution, and the abundances of microplastics in the middle and bottom waters were higher than the abundance in the surface water within the main estuary, which is subject to strong tidal action and has obvious stratification. The pumping method was more effective than the trawling method at retaining plastic fibers. The volume of water sample filtered by the pumping method and the size of the filtering mesh had significant effects on the abundances and sizes of the obtained microplastics. Different sampling methods lead to considerable differences in microplastic abundance results, and it is necessary to take tidal effects into account during microplastic monitoring in tidal estuaries. Therefore, it is recommended that operational monitoring and flux observations of microplastics in tidal estuaries be established and that sampling methods for observation of full tidal periods of flood and dry seasons and high and low tides should be used.

Key words: microplastics, sampling method, vertical distribution, the Jiulong River estuary

CLC Number:

P714+.5

Chunhua JIANG, Jinxu YI, Lixin ZHU, Kai LIU, Changxing ZONG, Daoji LI. Comparative study of the vertical distribution characteristics of microplastics and sampling methods for microplastics in the water column: A case study in the Jiulong River estuary[J]. Journal of East China Normal University(Natural Science), 2024, 2024(1): 79-89.

Figures/Tables 8

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References 32

1	李道季.. 海洋微塑料污染状况及其应对措施建议. 环境科学研究, 2019, 32 (2): 197- 202.
2	JAMBECK J R, GEYER R, WILCOX C, et al.. Plastic waste inputs from land into the ocean. Science, 2015, 347 (6223): 768- 771.
3	LEBRETON L, Evidence of the great pacific garbage patch is rapidly accumulating plastic [J]. Scientific Reports, 2018, 8(1): 4666.
4	MEIJIER L J J, EMMERIK T V, VAN DE ENT R J, et al.. More than 1000 rivers account for 80% of global riverine plastic emissions into the ocean. Science Advances, 2021, 7 (18): 5803.
5	李道季, 朱礼鑫, 常思远, 等.. 海洋微塑料污染研究发展态势及存在问题. 华东师范大学学报(自然科学版), 2019, (3): 174- 185.
6	BAI M, LIN Y, HURLEY R R, et al.. Controlling factors of microplastic riverine flux and implications for reliable monitoring strategy. Environmental Science & Technology, 2022, 56 (1): 48- 61.
7	李道季, 董旭日.. 海洋环境中的微塑料及其附着生物研究进展. 华东师范大学学报(自然科学版), 2022, 2022 (3): 1- 7.
8	MAI L, YOU S N, HE H, et al.. Riverine microplastic pollution in the pearl river delta, China: Are modeled estimates accurate?. Environmental Science & Technology, 2019, 53 (20): 11810- 11817.
9	GRAHAM E R, THOMPSON J T.. Deposit and suspension-feeding sea cucumbers (Echinodermata) ingest plastic fragments. Journal of Experimental Marine Biology and Ecology, 2009, 368 (1): 22- 29.
10	WU Y, WANG S, WU L, et al.. Vertical distribution and river-sea transport of microplastics with tidal fluctuation in a subtropical estuary, China. Science of the Total Environment, 2022, 822, 153603.
11	LIN H, PAN H, SUN J, et al.. Transboundary microplastic pollution in Xiamen Bay and adjacent Jiulong River estuary after the outbreak of COVID-19. Science of the Total Environment, 2023, 861, 160562.
12	王卫东, 洪华生, 张玉珍, 等.. 九龙江污染物入海通量初步估算. 海洋环境科学, 2006, 25 (2): 45- 47.
13	王晋沅, 江毓武.. 九龙江河口盐度分布及其通量的动力过程分析. 厦门大学学报(自然科学版), 2013, 52 (6): 835- 841.
14	LI D, LIU K, LI C, et al.. Profiling the vertical transport of microplastics in the West Pacific Ocean and the East Indian Ocean with a novel in situ filtration technique. Environmental Science & Technology, 2020, 54 (20): 12979- 12988.
15	SCHLITZER R. Ocean data view [DB/OL]. [2023-06-15]. https://odv.awi.de/.
16	LI Y, LIU S, LIU M, et al.. Mid-level riverine outflow matters: A case of microplastic transport in the Jiulong River, China. Frontiers in Marine Science, 2021, 8, 712727.
17	LI Y, XIAO P, DONNICI S, et al.. Spatial and seasonal distribution of microplastics in various environmental compartments around Sishili Bay of North Yellow Sea, China. Marine Pollution Bulletin, 2023, 186, 114372.
18	TANG G, LIU M, HE H, et al.. Microplastics and polycyclic aromatic hydrocarbons (PAHs) in Xiamen coastal areas: Implications for anthropogenic impacts. Science of the Total Environment, 2018, 634, 811- 820.
19	LENAKER P L, BALDWIN A K, KORSI S R, et al.. Vertical distribution of microplastics in the water column and surficial sediment from the Milwaukee River Basin to Lake Michigan. Environmental Science & Technology, 2019, 53 (21): 12227- 12237.
20	DAI Z, ZHANG H, ZHOU Q, et al.. Occurrence of microplastics in the water column and sediment in an inland sea affected by intensive anthropogenic activities. Environmental Pollution, 2018, 242, 1557- 1565.
21	LIN L, PAN X, ZHANG S, et al.. Distribution and source of microplastics in China’s second largest reservoir - Danjiangkou Reservoir. Journal of Environmental Sciences, 2021, 102, 74- 84.
22	DRIS R, GASPERI J, ROCHER V, et al.. Synthetic and non-synthetic anthropogenic fibers in a river under the impact of Paris Megacity: Sampling methodological aspects and flux estimations. Science of the Total Environment, 2018, 618, 157- 164.
23	SONG Y K, HONG S H, EO S, et al.. Horizontal and vertical distribution of microplastics in Korean coastal waters. Environmental Science & Technology, 2018, 52 (21): 12188- 12197.
24	DAANA K K L, GARDFELDT K, LYASHEVSKA O, et al.. Microplastics in sub-surface waters of the Arctic Central Basin. Marine Pollution Bulletin, 2018, 130, 8- 18.
25	LIU Y, YOU J A, LI Y J, et al.. Insights into the horizontal and vertical profiles of microplastics in a river emptying into the sea affected by intensive anthropogenic activities in Northern China. Science of the Total Environment, 2021, 779, 146589.
26	YANG R, XU X, ZHANG L, et al.. Horizontal and vertical distribution of microplastics in Gehu Lake, China. Water Supply, 2022, 22 (12): 8669- 8681.
27	LINDEQUE P K, COLE M, COPPOCK R L, et al.. Are we underestimating microplastic abundance in the marine environment? A comparison of microplastic capture with nets of different mesh-size. Environmental Pollution, 2020, 265, 114721.
28	LONG M, MORICEAU B, GALLINARI M, et al.. Interactions between microplastics and phytoplankton aggregates: Impact on their respective fates. Marine Chemistry, 2015, 175, 39- 46.
29	REISSER J, SALT B, NOBLE K, et al.. The vertical distribution of buoyant plastics at sea: An observational study in the North Atlantic Gyre. Biogeosciences, 2015, 12 (4): 1249- 1256.
30	ENDER K, LENZ R, STEDMON C A, et al.. Abundance, size and polymer composition of marine microplastics ≥10 μm in the Atlantic Ocean and their modelled vertical distribution. Marine Pollution Bulletin, 2015, 100 (1): 70- 81.
31	BRUNNER K, KUKULKA T, PROSKUROWSKI G, et al.. Passive buoyant tracers in the ocean surface boundary layer: 2. Observations and simulations of microplastic marine debris. Journal of Geophysical Research: Oceans, 2015, 120 (11): 7559- 7573.
32	STOCK F, KOCHLEUS C, BALTRUSCHAT B B, et al.. Sampling techniques and preparation methods for microplastic analyses in the aquatic environment – A review. Trends in Analytical Chemistry, 2019, 113, 84- 92.

研究来源	采样时间(年/月或季)	采样方式	采水体积	孔径/ μm	滤膜	九龙江河口塑料纤维检出率	结论
本研究	2019/8	表层水: 潜水泵; 中底层: 浮游生物泵	8 m³	60	玻璃纤维膜1.6 μm	表层17.61%, 中层64.77%, 底层45.81%	JLJ-1—JLJ-3站位平均值 (11.76 ± 8.28) 个/m³
Lin等^[11]	2021/冬季	Manta拖网	具体体积未提及	330	经过5 mm与0.3 mm不锈钢筛, 后将0.3 mm筛网上的微塑料过滤至0.7 mm玻璃纤维膜	纤维13.6%, 线状18.5%	1.30 个/m³
Wu等^[10]	2020/1	Manta拖网采集表层	具体体积未提及	333	分别过5 mm、300 μm、45 μm尼龙网	各水层均为碎片, 远多于纤维	九龙江河口湾处站位表层水0.8 个/m³, 次表层水 267 个/m³
Wu等^[10]	2020/1	自吸泵采集次表层 (0.5~1 m)及中层和底层	105 L	45	分别过5 mm、300 μm、45 μm尼龙网	各水层均为碎片, 远多于纤维	九龙江河口湾处站位表层水0.8 个/m³, 次表层水 267 个/m³
Li等^[16]	2019/4	44 μm潜水泵	150 ~ 200 L	20	先经过5 mm不锈钢筛, 再经过20 μm尼龙滤膜	5.80%	平均11.1 个/m³ (0.3 ~ 5 mm) , 232 个/m³ (44 ~ 330 μm); 泵采 (171.0 ± 85.5) 个/m³; 网采 (43.44 ± 2.48) 个/m³
Li等^[16]	2019/4	Manta拖网	约 300 m³	330	先经过5 mm不锈钢筛, 再经过20 μm尼龙滤膜	19.22%
Tang等^[18]	2017/3	Manta拖网	约 300 m³	330	尼龙滤膜20 μm	25.24%	九龙江河口表层水(438.8 ± 190.7) 个/m³, 东海近海(252.0 ± 58.9) 个/m³, 厦门岛西海域(695.8 ± 735.0) 个/m³

采样地点	采样方式	结论
渤海海域^[20]	采水器 (每个水层采集46 L)	渤海的5 ~ 15 m水深处积累更多微塑料, 小尺寸微塑料在更深的水层赋存, 水柱和沉积物中微塑料丰度存在显著性差异
韩国沿海水域^[23]	自制不锈钢采水器, 过滤100 L水样至20 μm筛网	每个水柱中聚丙烯与聚乙烯占绝大部分, 城市区域微塑料丰度高于农村
北极中央盆地^[24]	CTD采水器 (每个深度采集48 L)	次表层水中微塑料普遍存在, 并垂向输运至北冰洋中部
丹江口水库^[21]	5 L不锈钢采水器	中间水层微塑料含量显著高于表层水和底层水
海河^[25]	20 L不锈钢采水器采集表、中层水与底质上覆水	表、中层水微塑料浓度低于底质上覆水浓度, 特定区域 (如污水处理厂) 微塑料浓度高于普通区域
太湖^[26]	5 L采水器, 中、底层水使用潜水泵	微塑料浓度: 表层水>中层水>底层水
北黄海四十里湾^[17]	采水器 (每个水层采集20 L)	8月样品中、底层水微塑料浓度明显高于2、5和11月

[1]	Daoji LI, Xuri DONG. Research progress of microplastics and attached organisms in marine environment [J]. Journal of East China Normal University(Natural Science), 2022, 2022(3): 1-7.
[2]	LI Dao-ji, Zhu Li-xin, CHANG Si-yuan, ZHANG Feng, WANG Lu. State of marine microplastic pollution research and the limitations [J]. Journal of East China Normal University(Natural Sc, 2019, 2019(3): 174-185.
[3]	ZHU Chuan-fang;KONG Ya-zhen;DING Ping-xing . Experimental study of vertical sediment mixingcoefficients in 2D uniform flow (Chinese) [J]. Journal of East China Normal University(Natural Sc, 2008, 2008(1): 112-118.
[4]	YI Lan;YOU Wen-hui. Community Structure and Seasonal Change of Soil Animals in Castanopsis Fargesii Forest at Tiantong, Zhejiang Province(Chinese) [J]. Journal of East China Normal University(Natural Sc, 2006, 2006(2): 112-120.