Multiple isotopic compositions reveal complex nitrogen cycling in a subtropical estuary DOI
Hao Jiang, Jie Ma,

Huo Xu

et al.

Environmental Pollution, Journal Year: 2020, Volume and Issue: 272, P. 116410 - 116410

Published: Dec. 30, 2020

Language: Английский

Nutrient budgets for large Chinese estuaries DOI Creative Commons

S. M. Liu,

Gi Hoon Hong, J. Zhang

et al.

Biogeosciences, Journal Year: 2009, Volume and Issue: 6(10), P. 2245 - 2263

Published: Oct. 26, 2009

Abstract. Chinese rivers deliver about 5–10% of global freshwater input and 15–20% the continental sediment to world ocean. We report riverine fluxes concentrations major nutrients (nitrogen, phosphorus, silicon) in contiguous landmass China Korea northeast Asia. The are generally enriched with dissolved inorganic nitrogen (DIN) depleted phosphate (PO43−) very high DIN: PO43− concentration ratios. DIN, silicon levels loads mainly affected by agriculture activities urbanization, anthropogenic adsorption on particulates, rock types, climate physical denudation intensity, respectively. Nutrient transports summer 3–4 times higher than those winter exception NH4+. flux NH4+ is rather constant throughout year due sources such as sewer discharge. As nutrient composition has changed rivers, ecosystems estuaries coastal sea have also recent decades. Among changes, a shift limiting from phosphorus for phytoplankton production urbanization noticeable some areas becomes diatom productivity. A simple steady-state mass-balance box model was employed assess budgets estuaries. export <15% nitrogen, <6% required ~4% growth Seas (Bohai, Yellow Sea, East South Sea). This suggests that land-derived largely confined immediate estuaries, ecosystem beyond supported other regeneration, open ocean atmospheric deposition.

Language: Английский

Citations

289
Nitrogen cycling processes in sediments of the Pearl River Estuary: Spatial variations, controlling factors, and environmental implications DOI
Fangjuan Huang, Xianbiao Lin, Weifang Hu

et al.

CATENA, Journal Year: 2021, Volume and Issue: 206, P. 105545 - 105545

Published: June 25, 2021

Language: Английский

Citations

80
Phthalate esters in seawater and sediment of the northern South China Sea: Occurrence, distribution, and ecological risks DOI
Yaru Cao, Jing Li, Rongben Wu

et al.

The Science of The Total Environment, Journal Year: 2021, Volume and Issue: 811, P. 151412 - 151412

Published: Nov. 4, 2021

Language: Английский

Citations

72
Distal mud deposits associated with the Pearl River over the northwestern continental shelf of the South China Sea DOI
Yunling Liu, Shu Gao, Ya Ping Wang

et al.

Marine Geology, Journal Year: 2013, Volume and Issue: 347, P. 43 - 57

Published: Nov. 8, 2013

Language: Английский

Citations

97
Modeling the mass flux budgets of water and suspended sediments for the river network and estuary in the Pearl River Delta, China DOI
Jiatang Hu, Shiyu Li,

Bingxu Geng

et al.

Journal of Marine Systems, Journal Year: 2011, Volume and Issue: 88(2), P. 252 - 266

Published: May 21, 2011

Language: Английский

Citations

82
Sources, distributions, and early diagenesis of sedimentary organic matter in the Pearl River region of the South China Sea DOI
Yulong Zhang, Karl Kaiser, Li Li

et al.

Marine Chemistry, Journal Year: 2013, Volume and Issue: 158, P. 39 - 48

Published: Nov. 22, 2013

Language: Английский

Citations

73
Physical dynamics structures and oxygen budget of summer hypoxia in the Pearl River Estuary DOI Open Access
Yongsheng Cui, Jiaxue Wu, Jie Ren

et al.

Limnology and Oceanography, Journal Year: 2018, Volume and Issue: 64(1), P. 131 - 148

Published: Sept. 19, 2018

Abstract A summertime hypoxia sporadically occurred in the lower Pearl River Estuary (PRE) for more than three decades. Although its mechanism has already been extensively studied, topic on why seasonal is persistent patchy waters still an open question. Here, we presented investigation of physical dynamics structures and dissolved oxygen (DO) processes controlling spatial distribution maintenance coastal hypoxia. Field observations were conducted 2015 summer PRE adjacent shelf sea. High river discharge forms intense haloclines plume, while salinity intrusion benthic results a notable pycnocline at top salt wedge. mid‐depth transitional layer with weakest mixing over water column functions as barrier DO vertical exchange between plume appears overlapping zone Based biological processes, budget hypoxic system was established. The advection by gravitational circulation from roughly balanced bacterial respiration column. diffusion to completely inhibited layer. 30‐yr period can be satisfactorily predicted numerical simulations zones These findings will have important implication predicting mitigating Physical investigated understand Summertime appear near head intrusion, where inhibits DO‐rich well

Language: Английский

Citations

70
Isotopic evidence for the turnover of biological reactive nitrogen in the Pearl River Estuary, south China DOI Open Access
Feng Ye,

Zhixin Ni,

Luhua Xie

et al.

Journal of Geophysical Research Biogeosciences, Journal Year: 2015, Volume and Issue: 120(4), P. 661 - 672

Published: March 27, 2015

Abstract Nitrate (NO 3 − ) concentrations and the isotopic composition (δ 15 N δ 18 O) of water samples from Pearl River Estuary (PRE), south China, were measured to constrain sources processing in springtime. decreased at higher salinities, dual values correlated with 1/[NO ], both which suggest mixing eutrophic freshwater oligotrophic seawater. However, O did not closely follow expected lines. At low salinities (0–3.0), some exhibited high compared those riverine end‐member, indicating that sewage is a significant source nitrate (up 19.0% calculated N). >3.0, Δδ are linearly lnƒ (the fraction NO remaining system), attributable Rayleigh fractionation during phytoplankton uptake nitrate. linear relationship between different west east PRE, slope 1.18 1.59 east. This difference most likely resulted varying degrees nitrification due velocities residence times two areas. Our data therefore indicate signatures valuable way behavior river‐dominated estuaries.

Language: Английский

Citations

65
Increasing dissolved nitrogen and phosphorus export by the Pearl River (Zhujiang): a modeling approach at the sub-basin scale to assess effective nutrient management DOI Creative Commons
Maryna Strokal, Carolien Kroeze, Lili Li

et al.

Biogeochemistry, Journal Year: 2015, Volume and Issue: 125(2), P. 221 - 242

Published: July 17, 2015

The Pearl River (Zhujiang in Chinese) has been exporting excess of nitrogen (N) and phosphorus (P), causing eutrophication the coastal waters southern China for decades. However, sources these nutrients their locations are not well studied basin. As a consequence, it is difficult to formulate effective management options reduce river prevent further eutrophication. We developed sub-basin model based onto Global NEWS-2 (Nutrient Export from WaterSheds) period 1970–2050 analyze trends dissolved inorganic N P (DIN DIP) identify main locations. validated our by comparing modeled nutrient fluxes with observed. Future analyses on Millennium Ecosystem Assessment scenario that assumes globalized world reactive environmental management. DIN DIP inputs calculated increase factor 2–2.5 between 1970 2050. Over two-thirds stem two down-stream basins delta Dongjiang), where agriculture sewage important drivers this increase. Agriculture accounts over 40 % waters. Sewage account 90 inputs. Thus areas more reducing than up- middle-stream

Language: Английский

Citations

65
Mechanisms of nitrate accumulation in highly urbanized rivers: Evidence from multi-isotopes in the Pearl River Delta, China DOI
Yingxue Xuan, Changyuan Tang, Yingjie Cao

et al.

Journal of Hydrology, Journal Year: 2020, Volume and Issue: 587, P. 124924 - 124924

Published: April 3, 2020

Language: Английский

Citations

57