Article
Geography, Physical
Yiying Sun, Haixian Xiong, Man-Ting Lee, Chris Brodie, Yongqiang Zong
Summary: This study investigated the geochemical dynamics of sediment organic matter in mangrove wetlands and found significant exchanges of mangrove OM with marine and mixed forest OM. Despite these exchanges, distinct values of delta C-13, TOC and C/N were observed in modern surface sediments of different vegetational zones, confirming their usefulness as coastal environmental proxies. The proxies, combined with chronologies based on radiocarbon, 210 Pb and 137 Cs analyses, were successfully used to reconstruct the depositional history of the mangrove wetland, providing new insights into environmental responses to natural and anthropogenic drivers.
PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY
(2021)
Article
Environmental Sciences
In Ok Lee, Junsung Noh, Beomgi Kim, Inha Kwon, Hosang Kim, Bong-Oh Kwon, Yisheng Peng, Zhan Hu, Jong Seong Khim
Summary: Global recognition of the importance of mangroves in supporting coastal ecosystem services has increased, but research on trophic dynamics in mangrove ecosystems remains limited. This study analyzed stable isotopes in consumers and diets in the Pearl River Estuary to examine food web dynamics. The study found that fish had a larger niche space during the monsoon summer, indicating increased trophic roles. Benthos had a small niche space across seasons, indicating consistent trophic positions. The study also identified the use of different organic matters by consumers in different seasons. This study provides important insights into the seasonal and spatial trophic dynamics in mangrove forests, which can inform sustainable management of these ecosystems.
MARINE POLLUTION BULLETIN
(2023)
Article
Environmental Sciences
Mengting Li, Guisheng Song, Huixiang Xie
Summary: This study investigated the bio- and photo-lability of dissolved organic matter (DOM) in different areas of the Pearl River estuary. The headwater had higher levels of bio- and photo-labile DOM compared to the mixing zone and mouth, while the latter two had higher levels of bio- and photo-refractory DOM. The impact of pre-biotransformation on DOM photodegradation varied depending on the specific site. UV absorption coefficients were indicators of bio- and photo-refractory DOC, and the relative proportions of transparent and chromophoric DOM controlled the turnover of biolabile DOC and the effect of pre-biotransformation on DOM photodegradation.
MARINE POLLUTION BULLETIN
(2022)
Article
Environmental Sciences
Rong Zhong, Dingtian Yang, Linhong Zhao, Xiaoqing Yin
Summary: This study used satellite remote sensing technology and sediment data to estimate the distribution of biosiliceous sedimentation flux in the Pearl River Estuary. The results showed significant seasonal variation and an increasing trend over the years, which differed from the trend in coastal open waters. The study also found that biosiliceous sedimentation flux is influenced by two factors: chromophoric dissolved organic matter and total suspended solids. This research enhances our understanding of the marine biogeochemical cycle.
Article
Environmental Sciences
Jia-Ling Li, Li Duan, Ying Wu, Manzoor Ahmad, Ling-Zi Yin, Xiao-Qing Luo, Xin Wang, Bao-Zhu Fang, Shan-Hui Li, Li-Nan Huang, Jia-Xue Wu, Xiao-Zhen Mou, Pandeng Wang, Wen-Jun Li
Summary: Estuaries play a crucial role in the global carbon cycle by transforming and burying terrestrial organic carbon (TerrOC). However, the specific taxa and degradation processes involved in TerrOC transformation and degradation in estuaries are largely unknown. In this study, sediment samples from the Pearl River Estuary in China were analyzed using analytical chemistry, metagenomics, and bioinformatics methods. The study identified diverse bacterial and archaeal taxa, including previously unknown lignin degraders, and determined the spatial distribution patterns of lignin degradation pathways genes. The study also found significant correlations between abundance of certain metabolic pathways genes and degree of lignin oxidation and vegetation source. Overall, this study provides valuable insights into the microbial ecology of TerrOC degradation in estuaries.
Article
Geochemistry & Geophysics
Peihong Kang, Han Zhang, Zixiang Yang, Yifan Zhu, Biyan He, Qing Li, Cindy Lee, Tiantian Tang
Summary: This study measured stable carbon isotope patterns of individual amino acids in suspended particles and surface sediments from the Pearl River Estuary in China, revealing that the carbon isotope values of individual amino acids gradually increase with salinity, indicating an increase in algal-derived organic carbon along the salinity gradient. Additionally, the isotopic difference between amino acids and bulk organic carbon varied significantly, with labile organic carbon contributing more to suspended particles than sediments. Using a Lability Model, dynamic contributions of semi-labile algal-derived organic carbon and terrestrial organic carbon to estuarine particulate organic carbon were evaluated, highlighting the importance of decomposition in shaping the composition and isotopic signature of particulate organic carbon in the estuary.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2021)
Article
Engineering, Environmental
Jia-Yong Lao, Rongben Wu, Yongsheng Cui, Shiwen Zhou, Yuefei Ruan, Kenneth M. Y. Leung, Jiaxue Wu, Eddy Y. Zeng, Paul K. S. Lam
Summary: The study highlights the importance of atmospheric deposition and surface runoff as pathways for OPEs to enter and migrate in the Pearl River Estuary; the particle-mediated transport of OPEs is influenced by various factors, including physicochemical properties, environmental factors, and marine microbial activities; there is a need for increased attention to the input and environmental fate of OPEs in the estuary.
JOURNAL OF HAZARDOUS MATERIALS
(2022)
Article
Environmental Sciences
Ziming Fang, Wen-Xiong Wang
Summary: The Pearl River Estuary in Southern China, the largest estuary in the region, regulates the fluxes of riverine trace metals into the South China Sea. The study found that trace metals undergo transformations between different phases during estuarine mixing, with an increase in dissolved metal concentration accompanied by a decrease in particulate metal concentration.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Environmental Sciences
Wenjie Fan, Zhihao Xu, Qian Dong, Weiru Chen, Yanpeng Cai
Summary: This study used remote sensing retrieval to explore the long-term water quality variation and driving mechanisms in China's Pearl River Estuary (PRE). The results showed significant spatial and temporal variability in chlorophyll-a (Chl-a) concentrations, with higher concentrations in the western section and lower concentrations in the eastern section. Chl-a concentrations were significantly correlated with environmental factors and anthropogenic activities. This study provides valuable insights for water quality improvement and sustainable development in the PRE's Greater Bay Area (GBA).
FRONTIERS IN MARINE SCIENCE
(2023)
Article
Environmental Sciences
Ana Gabriela Bonelli, Hubert Loisel, Daniel S. F. Jorge, Antoine Mangin, Odile Fanton d'Andon, Vincent Vantrepotte
Summary: This study presents a new approach for estimating dissolved organic carbon (DOC) over the open ocean using an artificial neural network algorithm. By considering various factors such as optical water classes, sea surface temperature, mixed layer depth, absorption coefficient of dissolved organic matter, and chlorophyll-a concentration, the model successfully estimates DOC from satellite data and shows good agreement with in situ measurements. Additionally, the study provides insight into the contribution of particulate organic carbon (POC) to total organic carbon (TOC) over the global ocean.
REMOTE SENSING OF ENVIRONMENT
(2022)
Article
Engineering, Marine
Dongliang Wang, Lijun Yao, Jing Yu, Pimao Chen, Ruirui Hu
Summary: Spawning grounds are crucial for fish survival and reproduction, with the Pearl River Estuary being influenced by environmental factors such as sea surface temperature. The movement of the spawning ground from the outlet of the estuary to the east occurs from spring to summer.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2021)
Article
Environmental Sciences
Wenpeng Li, Xinxin Li, Xin Zhao, Chengpeng Sun, Tianyi Nie, Yumei Hu, Chunzai Wang
Summary: The burial of organic carbon (OC) in the Pearl River Estuary (PRE) is influenced by both climate change and human disturbances. Different stages of sediment deposition in the past 130 years show variations in the burial of marine derived OC and petrogenic OC. The input of terrestrial OC is correlated with climate oscillation indexes before 1957 and the Atlantic Multidecadal Oscillation between 1957 and 1980. Human disturbances, such as deforestation and dam construction, have significantly affected the land derived OC content since the 1980s.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Environmental Sciences
Zhilong Zhao, Xiaolan Cai, Changchun Huang, Kun Shi, Jianhong Li, Jiale Jin, Hao Yang, Tao Huang
Summary: This article proposes a novel inversion algorithm based on remote sensing and geochemical isotopes for estimating particulate organic carbon (POC) concentrations in inland water. The algorithm has been validated and shown to accurately derive POC concentrations, revealing the temporal and spatial variations in POC in Lake Taihu.
REMOTE SENSING OF ENVIRONMENT
(2022)
Article
Environmental Sciences
Junjun Huang, Zhisheng Zhang, Jun Tao, Leiming Zhang, Fuli Nie, Leilei Fei
Summary: Ambient fine particulate matter (PM2.5) levels in South China have been decreasing, with carbonaceous aerosols showing a smaller decrease rate. A comprehensive campaign in urban Guangzhou revealed that traffic emissions were the most important source of carbonaceous aerosols, highlighting the importance of promoting clean energy vehicles and relieving urban traffic congestion.
ENVIRONMENTAL RESEARCH
(2022)
Article
Environmental Sciences
Xin Li, Haiming Yan, Ying Yang, Zhihao Xu, Huicai Yang
Summary: This study examines the coastline variation of the Pearl River Estuary in China using Landsat satellite images from 1987 to 2017. The results show that the estuary has experienced significant expansion during recent decades, with the length of the coastline increasing by 74.81 km and the land area increasing by 679.25 km(2). The study also identifies the dominant factors influencing coastline variation, including reductions in sand content caused by reservoir construction and river dredging, as well as urbanization and land reclamation for aquaculture. These findings have important implications for understanding the impact of human activities on coastline variation and can inform sustainable management strategies for estuaries.
FRONTIERS IN MARINE SCIENCE
(2022)
