The impact of submarine groundwater discharge on nitrogen input and nitrogen cycling processes in a southern Portugal lagoon

Sun Danqing; Lai Longyun; Xu Yi; Jiang Shan

Article Contents

Article Navigation > Haiyang Xuebao > 2026 > Accepted Manuscript

Sun Danqing，Lai Longyun，Xu Yi, et al. The impact of submarine groundwater discharge on nitrogen input and nitrogen cycling processes in a southern Portugal lagoon[J]. Haiyang Xuebao，2026, 48(x)：1–14

Citation:

PDF( 3359 KB)

The impact of submarine groundwater discharge on nitrogen input and nitrogen cycling processes in a southern Portugal lagoon

Sun Danqing^1
,,
Lai Longyun¹,
Xu Yi¹,
Jiang Shan^{1
,
,}

State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai 200241, China

Received Date: 2026-04-07
Rev Recd Date: 2026-05-13

Available Online: 2026-06-09

Abstract

Abstract

This study investigated the nitrogen input characteristics of submarine groundwater discharge (SGD) and its influence on the nitrogen biogeochemical cycle in the Ria Formosa lagoon system in Faro, southern Portugal, during the early summer season. The results showed that although biogeochemical processes within the subterranean estuary significantly reduce the nitrogen load transported by SGD, it remained an important source of nitrogen nutrients to the lagoon. The SGD-derived nitrate flux into the lagoon was as high as 1.3(±1.0) ×10³ kg/d, and the flux of dissolved organic nitrogen (DON) was 220.3(±163.3) kg/d, contributing 89% of the total nitrate input and 37% of the total DON input to the lagoon, respectively. End-member analysis further revealed that approximately 98% of nitrate and 76% of DON originated from freshwater groundwater, highlighting the potential pressure of land-sourced groundwater nitrogen pollution on coastal ecosystems. A 48-hour in situ continuous monitoring in the lagoon revealed that externally sourced nitrate from SGD was rapidly removed from the lagoon system, with a removal rate of 69.9(±68.5) μmol N/(m²·h). Considering the lagoon area, the estimated total daily net nitrate removal in the lagoon is equivalent to 8.9 times the total nitrate input from SGD. This result indicates that the biogeochemical nitrate removal processes within the lagoon are highly active, with a combined removal capacity far exceeding that of the SGD input alone; the lagoon as a whole thus acts as an efficient nitrate sink. Concurrently, the net production rate of DON was as high as 36.3(±35.4) μmol N-DON/(m²·h), indicating that the substantial input of land-sourced nitrate significantly enhanced biological assimilation within the lagoon ecosystem. Therefore, future efforts should prioritize the long-term monitoring and precise management of SGD-derived nitrogen inputs to ensure the health and sustainable development of coastal lagoon ecosystems.
- Submarine groundwater discharge,
- Subterranean estuary,
- Radon,
- Nitrogen,
- Portugal

FullText(HTML)

References(82)

References

[1]	Wåhlström I, Almroth-Rosell E, Edman M, et al. Increased nutrient retention and cyanobacterial blooms in a future coastal zone[J]. Estuarine, Coastal and Shelf Science, 2024, 301: 108728. doi: 10.1016/j.ecss.2024.108728
[2]	Fu Yandan, Kang Jiahui, Li Ziyue, et al. Concentrations and fluxes of dissolved nutrients in the Yangtze River: long-term trends and ecological impacts[J]. Frontiers of Agricultural Science and Engineering, 2021, 8(4): 559−567. doi: 10.15302/J-FASE-2020344
[3]	Lønborg C, Müller M, Butler E C V, et al. Nutrient cycling in tropical and temperate coastal waters: is latitude making a difference?[J]. Estuarine, Coastal and Shelf Science, 2021, 262: 107571. doi: 10.1016/j.ecss.2021.107571
[4]	Stackpoole S, Sabo R, Falcone J, et al. Long-term Mississippi river trends expose shifts in the river load response to watershed nutrient balances between 1975 and 2017[J]. Water Resources Research, 2021, 57(11): e2021WR030318. doi: 10.1029/2021WR030318
[5]	王猛, 王玉珏, 刘栋, 等. 胶州湾水体和表层沉积物营养环境现状及影响因素[J]. 海洋学报, 2022, 44(10): 49−62. Wang Meng, Wang Yujue, Liu Dong, et al. Nutritional environment and influencing factors of seawater and surface sediments in the Jiaozhou Bay[J]. Haiyang Xuebao, 2022, 44(10): 49−62.
[6]	Young N, Sharpe R A, Barciela R, et al. Marine harmful algal blooms and human health: a systematic scoping review[J]. Harmful Algae, 2020, 98: 101901. doi: 10.1016/j.hal.2020.101901
[7]	Oliver A C, Kurylyk B L, Johnston L H, et al. Impacts of climate change and best management practices on nitrate loading to a eutrophic coastal lagoon[J]. Frontiers in Environmental Science, 2024, 12: 1468869. doi: 10.3389/fenvs.2024.1468869
[8]	Wang Yujue, Liu Dongyan, Xiao Wupeng, et al. Coastal eutrophication in China: trend, sources, and ecological effects[J]. Harmful Algae, 2021, 107: 102058. doi: 10.1016/j.hal.2021.102058
[9]	Duce R A, LaRoche J, Altieri K, et al. Impacts of atmospheric anthropogenic nitrogen on the open ocean[J]. Science, 2008, 320(5878): 893−897. doi: 10.1126/science.1150369
[10]	Wilson S J, Anderson I C, Song B, et al. Temporal and spatial variations in subterranean estuary geochemical gradients and nutrient cycling rates: impacts on groundwater nutrient export to estuaries[J]. Journal of Geophysical Research: Biogeosciences, 2023, 128(6): e2022JG007132. doi: 10.1029/2022JG007132
[11]	Jiang Shan, Hossain M J, Uddin S A, et al. Nitrogen accumulation and attenuation in the Ganges-Brahmaputra-Meghna river system: an evaluation with multiple stable isotopes and microbiota[J]. Marine Pollution Bulletin, 2023, 193: 115204. doi: 10.1016/j.marpolbul.2023.115204
[12]	Zhang Jing, Zhang Guosen, Du Yanan, et al. From the water sources of the Tibetan Plateau to the ocean: state of nutrients in the Changjiang linked to land use changes and climate variability[J]. Science China Earth Sciences, 2022, 65(11): 2127−2174. doi: 10.1007/s11430-021-9969-0
[13]	Wilson S J, Moody A, McKenzie T, et al. Global subterranean estuaries modify groundwater nutrient loading to the ocean[J]. Limnology and Oceanography Letters, 2024, 9(4): 411−422. doi: 10.1002/lol2.10390
[14]	Santos I R, Chen Xiaogang, Lecher A L, et al. Submarine groundwater discharge impacts on coastal nutrient biogeochemistry[J]. Nature Reviews Earth & Environment, 2021, 2(5): 307−323. doi: 10.1038/s43017-021-00152-0
[15]	Cho H M, Kim G, Kwon E Y, et al. Radium tracing nutrient inputs through submarine groundwater discharge in the global ocean[J]. Scientific Reports, 2018, 8(1): 2439. doi: 10.1038/s41598-018-20806-2
[16]	Xu Cheng, Wang Xilong, Zhang Fenfen, et al. Potential linkages between submarine groundwater (fresh and saline) nutrient inputs and eutrophication in a coastal aquaculture bay[J]. Journal of Geophysical Research: Oceans, 2024, 129(10): e2024JC021501. doi: 10.1029/2024JC021501
[17]	Zhang Yan, Santos I R, Li Hailong, et al. Submarine groundwater discharge drives coastal water quality and nutrient budgets at small and large scales[J]. Geochimica et Cosmochimica Acta, 2020, 290: 201−215. doi: 10.1016/j.gca.2020.08.026
[18]	Luijendijk E, Gleeson T, Moosdorf N. Fresh groundwater discharge insignificant for the world’s oceans but important for coastal ecosystems[J]. Nature Communications, 2020, 11(1): 1260. doi: 10.1038/s41467-020-15064-8
[19]	Wang Xuejing, Li Hailong, Zheng Chunmiao, et al. Submarine groundwater discharge as an important nutrient source influencing nutrient structure in coastal water of Daya Bay, China[J]. Geochimica et Cosmochimica Acta, 2018, 225: 52−65. doi: 10.1016/j.gca.2018.01.029
[20]	Santos I R, Eyre B D, Glud R N. Influence of porewater advection on denitrification in carbonate sands: evidence from repacked sediment column experiments[J]. Geochimica et Cosmochimica Acta, 2012, 96: 247−258. doi: 10.1016/j.gca.2012.08.018
[21]	Yu Xueqing, Liu Jian’an, Zhu Zhuoyi, et al. The significant role of submarine groundwater discharge in an Arctic fjord nutrient budget[J]. Acta Oceanologica Sinica, 2024, 43(10): 74−85. doi: 10.1007/s13131-024-2418-4
[22]	Bernard R J, Mortazavi B, Wang Lei, et al. Benthic nutrient fluxes and limited denitrification in a sub-tropical groundwater-influenced coastal lagoon[J]. Marine Ecology Progress Series, 2014, 504: 13−26. doi: 10.3354/meps10783
[23]	Luo Manhua, Zhang Yan, Xiao Kai, et al. Effect of submarine groundwater discharge on nutrient distribution and eutrophication in Liaodong Bay, China[J]. Water Research, 2023, 247: 120732. doi: 10.1016/j.watres.2023.120732
[24]	Zhu Tianyi, Zhao Shibin, Xu Bochao, et al. Large scale submarine groundwater discharge dominates nutrient inputs to China’s coast[J]. Nature Communications, 2025, 16(1): 2932. doi: 10.1038/s41467-025-58103-y
[25]	Couturier M, Tommi-Morin G, Sirois M, et al. Nitrogen transformations along a shallow subterranean estuary[J]. Biogeosciences, 2017, 14(13): 3321−3336. doi: 10.5194/bg-14-3321-2017
[26]	Li Dongsheng, Zhao Yunduo, Liu Zhongfang. Nitrogen transformation and drivers in response to hydrological variability in the Yangtze subterranean estuary[J]. Journal of Environmental Management, 2025, 391: 126474. doi: 10.1016/j.jenvman.2025.126474
[27]	Moore W S. The subterranean estuary: a reaction zone of ground water and sea water[J]. Marine Chemistry, 1999, 65(1/2): 111−125. doi: 10.1016/s0304-4203(99)00014-6
[28]	Ruiz-González C, Rodellas V, Garcia-Orellana J. The microbial dimension of submarine groundwater discharge: current challenges and future directions[J]. FEMS Microbiology Reviews, 2021, 45(5): fuab010. doi: 10.1093/femsre/fuab010
[29]	姜伟, 杨浩丹, 吴星媛, 等. 珊瑚礁区海底地下水排泄的环境效应及其珊瑚记录研究进展[J]. 海洋学报, 2020, 42(11): 1−11. Jiang Wei, Yang Haodan, Wu Xingyuan, et al. Research progress of environmental influence and coral record of submarine groundwater discharge in coral reefs[J]. Haiyang Xuebao, 2020, 42(11): 1−11.
[30]	Leote C, Ibánhez J S, Rocha C. Submarine groundwater discharge as a nitrogen source to the Ria Formosa studied with seepage meters[J]. Biogeochemistry, 2008, 88(2): 185−194. doi: 10.1007/s10533-008-9204-9
[31]	Beusen A H W, Slomp C P, Bouwman A F. Global land-ocean linkage: direct inputs of nitrogen to coastal waters via submarine groundwater discharge[J]. Environmental Research Letters, 2013, 8(3): 034035. doi: 10.1088/1748-9326/8/3/034035
[32]	Tait D R, Erler D V, Santos I R, et al. The influence of groundwater inputs and age on nutrient dynamics in a coral reef lagoon[J]. Marine Chemistry, 2014, 166: 36−47. doi: 10.1016/j.marchem.2014.08.004
[33]	Newton A, Icely J D, Falcao M, et al. Evaluation of eutrophication in the Ria Formosa coastal lagoon, Portugal[J]. Continental Shelf Research, 2003, 23(17/19): 1945−1961. doi: 10.1016/j.csr.2003.06.008
[34]	Domingues R B, Nogueira P, Barbosa A B. Co-limitation of phytoplankton by N and P in a shallow coastal lagoon (Ria Formosa): implications for eutrophication evaluation[J]. Estuaries and Coasts, 2023, 46(6): 1557−1572. doi: 10.1007/s12237-023-01230-w
[35]	Ferreira J G, Simas T, Nobre A, et al. Identification of Sensitive Areas and Vulnerable Zones in Transitional and Coastal Portuguese Systems: Application of the United States National Estuarine Eutrophication Assessment to the Minho, Lima, Douro, Ria de Aveiro, Mondego, Tagus, Sado, Mira, Ria Formosa and Guadiana Systems[M]. Lisboa: INAG-Instituto da Água, 2003.
[36]	Rocha C, Veiga-Pires C, Scholten J, et al. Assessing land–ocean connectivity via Submarine Groundwater Discharge (SGD) in the Ria Formosa Lagoon (Portugal): combining radon measurements and stable isotope hydrology[J]. Hydrology and Earth System Sciences, 2016, 20(8): 3077−3098. doi: 10.5194/hess-20-3077-2016
[37]	Aníbal J, Gomes A, Mendes I, et al. Ria Formosa: Challenges of A Coastal Lagoon in A Changing Environment[M]. Faro: Universidade do Algarve, 2019. (查阅网上资料, 请确认修改是否正确)
[38]	Pacheco A, Ferreira Ó, Williams J J, et al. Hydrodynamics and equilibrium of a multiple-inlet system[J]. Marine Geology, 2010, 274(1/4): 32−42. doi: 10.1016/j.margeo.2010.03.003
[39]	Balouin Y, Howa H, Michel D. Swash platform morphology in the ebb-tidal delta of the Barra Nova inlet, South Portugal[J]. Journal of Coastal Research, 2001, 17(4): 784−791.
[40]	Synthesis R. Development of an Information Technology Tool for the Management of European Southern Lagoons Under the Influence of River-Basin Runoff[D]. Porto: University Fernanda Pesson, 2003. (查阅网上资料, 未找到本条文献作者及出版信息且未能确认文献类型, 请确认)
[41]	Oduor N A, Cristina S C, Costa P. Sources of anthropogenic nutrients and their implications on nutrient chemistry and ecological conditions of Ria Formosa lagoon, Portugal[J]. Regional Studies in Marine Science, 2023, 61: 102843. doi: 10.1016/j.rsma.2023.102843
[42]	Stigter T Y, Ribeiro L, Carvalho Dill A M M. Application of a groundwater quality index as an assessment and communication tool in agro-environmental policies–Two Portuguese case studies[J]. Journal of Hydrology, 2006, 327(3/4): 578−591. doi: 10.1016/j.jhydrol.2005.12.001
[43]	Arnaud-Fassetta G, Bertrand F, Costa S, et al. The western lagoon marshes of the Ria Formosa (Southern Portugal): sediment-vegetation dynamics, long-term to short-term changes and perspective[J]. Continental Shelf Research, 2006, 26(3): 363−384. doi: 10.1016/j.csr.2005.12.008
[44]	Jiang Shan, Ibánhez J S P, Carvalho L, et al. Seasonal variation of nitrogen transformations in a subterranean estuary on the Ria Formosa lagoon barrier islands, Portugal[J]. Acta Oceanologica Sinica, 2026, 45(1): 1-13. (查阅网上资料, 未找到本条文献卷期页码信息, 请确认)
[45]	Jiang Shan, Kavanagh M, Rocha C. Evaluation of the suitability of vacutainers for storage of nutrient and dissolved organic carbon analytes in water samples[J]. Biology and Environment: Proceedings of the Royal Irish Academy, 2017, 117B(1): 33-46.
[46]	Charbonnier C, Anschutz P, Tamborski J, et al. Benthic fluxes and mineralization processes at the scale of a coastal lagoon: permeable versus fine-grained sediment contribution[J]. Marine Chemistry, 2023, 254: 104274. doi: 10.1016/j.marchem.2023.104274
[47]	Flechard C R, Nemitz E, Smith R I, et al. Dry deposition of reactive nitrogen to European ecosystems: a comparison of inferential models across the NitroEurope network[J]. Atmospheric Chemistry and Physics, 2011, 11(6): 2703−2728. doi: 10.5194/acp-11-2703-2011
[48]	Tett P, Gilpin L, Svendsen H, et al. Eutrophication and some European waters of restricted exchange[J]. Continental Shelf Research, 2003, 23(17/19): 1635−1671. doi: 10.1016/j.csr.2003.06.013
[49]	Grasshoff K, Kremling K, Ehrhardt M. Methods of Seawater Analysis[M]. 3rd ed. Weinheim: Wiley-VCH, 2009.
[50]	Cohen E R. An introduction to error analysis: the study of uncertainties in physical measurements[J]. Measurement Science and Technology, 1998, 9(6): 022. doi: 10.1088/0957-0233/9/6/022
[51]	Paytan A, Shellenbarger G G, Street J H, et al. Submarine groundwater discharge: an important source of new inorganic nitrogen to coral reef ecosystems[J]. Limnology and Oceanography, 2006, 51(1): 343−348.
[52]	Wayland D, Megson D P, Mudge S M, et al. Identifying the source of nutrient contamination in a lagoon system[J]. Environmental Forensics, 2008, 9(2/3): 231−239. doi: 10.1080/15275920802122833
[53]	Gari S R, Newton A, Icely J, et al. Testing the application of the Systems Approach Framework (SAF) for the management of eutrophication in the Ria Formosa[J]. Marine Policy, 2014, 43: 40−45. doi: 10.1016/j.marpol.2013.03.017
[54]	Rocha C, Ibánhez J S P, Leote C. Benthic nitrate biogeochemistry affected by tidal modulation of Submarine Groundwater Discharge (SGD) through a sandy beach face, Ria Formosa, Southwestern Iberia[J]. Marine Chemistry, 2009, 115(1/2): 43−58. doi: 10.1016/j.marchem.2009.06.003
[55]	Rocha C, Jiang S, Ibánhez J S P, et al. The effects of subterranean estuary dynamics on nutrient resource ratio availability to microphytobenthos in a coastal lagoon[J]. Science of the Total Environment, 2022, 851: 157522. doi: 10.1016/j.scitotenv.2022.157522
[56]	Kim T H, Kwon E, Kim I, et al. Dissolved organic matter in the subterranean estuary of a volcanic island, Jeju: importance of dissolved organic nitrogen fluxes to the ocean[J]. Journal of Sea Research, 2013, 78: 18−24. doi: 10.1016/j.seares.2012.12.009
[57]	Lee Y W, Hwang D W, Kim G, et al. Nutrient inputs from submarine groundwater discharge (SGD) in Masan Bay, an embayment surrounded by heavily industrialized cities, Korea[J]. Science of the Total Environment, 2009, 407(9): 3181−3188. doi: 10.1016/j.scitotenv.2008.04.013
[58]	Niencheski L F H, Windom H L, Moore W S, et al. Submarine groundwater discharge of nutrients to the ocean along a coastal lagoon barrier, Southern Brazil[J]. Marine Chemistry, 2007, 106(3/4): 546−561. doi: 10.1016/j.marchem.2007.06.004
[59]	Liu Sumei, Li Ruihuan, Zhang Guiling, et al. The impact of anthropogenic activities on nutrient dynamics in the tropical Wenchanghe and Wenjiaohe Estuary and Lagoon system in East Hainan, China[J]. Marine Chemistry, 2011, 125(1/4): 49−68.
[60]	Knee K L, Layton B A, Street J H, et al. Sources of nutrients and fecal indicator bacteria to nearshore waters on the north shore of Kaua`i (Hawa`i, USA)[J]. Estuaries and Coasts, 2008, 31(4): 607−622. doi: 10.1007/s12237-008-9055-6
[61]	Santos I R S, Burnett W C, Chanton J, et al. Nutrient biogeochemistry in a Gulf of Mexico subterranean estuary and groundwater-derived fluxes to the coastal ocean[J]. Limnology and Oceanography, 2008, 53(2): 705−718. doi: 10.4319/lo.2008.53.2.0705
[62]	Lee C M, Jiao J J, Luo Xin, et al. Estimation of submarine groundwater discharge and associated nutrient fluxes in Tolo Harbour, Hong Kong[J]. Science of the Total Environment, 2012, 433: 427−433. doi: 10.1016/j.scitotenv.2012.06.073
[63]	Taniguchi M, Burnett W C, Dulaiova H, et al. Groundwater discharge as an important land-sea pathway into Manila Bay, Philippines[J]. Journal of Coastal Research, 2008, 24(sp1): 15−24. doi: 10.2112/06-0636.1
[64]	Rocha C, Wilson J, Scholten J, et al. Retention and fate of groundwater-borne nitrogen in a coastal bay (Kinvara Bay, Western Ireland) during summer[J]. Biogeochemistry, 2015, 125(2): 275−299. doi: 10.1007/s10533-015-0116-1
[65]	Chen Xiaogang, Cukrov N, Santos I R, et al. Karstic submarine groundwater discharge into the Mediterranean: radon-based nutrient fluxes in an anchialine cave and a basin-wide upscaling[J]. Geochimica et Cosmochimica Acta, 2020, 268: 467−484. doi: 10.1016/j.gca.2019.08.019
[66]	Peng Tong, Yu Xueqing, Liu Jianan, et al. Capturing the influence of submarine groundwater discharge on nutrient speciation dynamics within an estuarine aquaculture ecosystem[J]. Environmental Pollution, 2023, 336: 122467. doi: 10.1016/j.envpol.2023.122467
[67]	Wang Xilong, Su Kaijun, Chen Xiaogang, et al. Submarine groundwater discharge-driven nutrient fluxes in a typical mangrove and aquaculture bay of the Beibu Gulf, China[J]. Marine Pollution Bulletin, 2021, 168: 112500. doi: 10.1016/j.marpolbul.2021.112500
[68]	Ribot M, von Schiller D, Martí E. Understanding pathways of dissimilatory and assimilatory dissolved inorganic nitrogen uptake in streams[J]. Limnology and Oceanography, 2017, 62(3): 1166−1183. doi: 10.1002/lno.10493
[69]	Aldunate M, Henríquez-Castillo C, Ji Qixing, et al. Nitrogen assimilation in picocyanobacteria inhabiting the oxygen-deficient waters of the eastern tropical North and South Pacific[J]. Limnology and Oceanography, 2020, 65(2): 437−453. doi: 10.1002/lno.11315
[70]	Rocha C, Galvão H, Barbosa A. Role of transient silicon limitation in the development of cyanobacteria blooms in the Guadiana estuary, south-western Iberia[J]. Marine Ecology Progress Series, 2002, 228: 35−45.
[71]	Watzer B, Spät P, Neumann N, et al. The signal transduction protein P_II controls ammonium, nitrate and urea uptake in cyanobacteria[J]. Frontiers in Microbiology, 2019, 10: 1428. doi: 10.3389/fmicb.2019.01428
[72]	Ning Zhiming, Xia Ronglin, Yang Bin, et al. Sedimentary nitrogen dynamics in a coastal reef area with relatively high nitrogen concentration[J]. Acta Oceanologica Sinica, 2023, 42(4): 33−40. doi: 10.1007/s13131-022-2088-z
[73]	Jensen M M, Lam P, Revsbech N P, et al. Intensive nitrogen loss over the Omani Shelf due to anammox coupled with dissimilatory nitrite reduction to ammonium[J]. The ISME Journal, 2011, 5(10): 1660−1670. doi: 10.1038/ismej.2011.44
[74]	Magri M, Benelli S, Bonaglia S, et al. The effects of hydrological extremes on denitrification, dissimilatory nitrate reduction to ammonium (DNRA) and mineralization in a coastal lagoon[J]. Science of the Total Environment, 2020, 740: 140169. doi: 10.1016/j.scitotenv.2020.140169
[75]	Murray L G, Mudge S M, Newton A, et al. The effect of benthic sediments on dissolved nutrient concentrations and fluxes[J]. Biogeochemistry, 2006, 81(2): 159−178. doi: 10.1007/s10533-006-9034-6
[76]	Hylén A, Taylor D, Kononets M, et al. In situ characterization of benthic fluxes and denitrification efficiency in a newly re-established mussel farm[J]. Science of the Total Environment, 2021, 782: 146853. doi: 10.1016/j.scitotenv.2021.146853
[77]	Lønborg C, Carreira C, Abril G, et al. A global database of dissolved organic matter (DOM) concentration measurements in coastal waters (CoastDOM v1)[J]. Earth System Science Data, 2024, 16(2): 1107−1119. doi: 10.5194/essd-16-1107-2024
[78]	Uchiyama Y, Nadaoka K, Rölke P, et al. Submarine groundwater discharge into the sea and associated nutrient transport in a Sandy Beach[J]. Water Resources Research, 2000, 36(6): 1467−1479. doi: 10.1029/2000WR900029
[79]	Zheng Yanling, Hou Lijun, Zhang Zongxiao, et al. Overlooked contribution of water column to nitrogen removal in estuarine turbidity maximum zone (TMZ)[J]. Science of the Total Environment, 2021, 788: 147736. doi: 10.1016/j.scitotenv.2021.147736
[80]	Reckhardt A, Beck M, Seidel M, et al. Carbon, nutrient and trace metal cycling in sandy sediments: a comparison of high-energy beaches and backbarrier tidal flats[J]. Estuarine, Coastal and Shelf Science, 2015, 159: 1−14. doi: 10.1016/j.ecss.2015.03.025
[81]	冯立娜, 张海波, 孙雨嫣, 等. 浒苔绿潮消亡腐败过程中的营养盐释放及其对近海环境的影响[J]. 海洋学报, 2020, 42(8): 59−68. doi: 10.3969/j.issn.0253-4193.2020.08.007 Feng Li'na, Zhang Haibo, Sun Yuyan, et al. On nutrient releases from the decomposition of Ulva prolifera green tide and their impacts on nearshore seawaters in the southern Yellow Sea[J]. Haiyang Xuebao, 2020, 42(8): 59−68. doi: 10.3969/j.issn.0253-4193.2020.08.007
[82]	Hobbie J E, Hobbie E A. Microbes in nature are limited by carbon and energy: the starving-survival lifestyle in soil and consequences for estimating microbial rates[J]. Frontiers in Microbiology, 2013, 4: 324. doi: 10.3389/fmicb.2013.00324