Next Article in Journal
Correction: Liu, D.; Manousos V.; Richard W. Flow Hydrodynamics across Open Channel Flows with Riparian Zones: Implications for Riverbank Stability. Water, 9, 720
Next Article in Special Issue
Phosphorus Fluxes from Three Coastal Watersheds under Varied Agriculture Intensities to the Northern Gulf of Mexico
Previous Article in Journal
Do As They Did: Peer Effects Explain Adoption of Conservation Agriculture in Malawi
Previous Article in Special Issue
Permafrost Boundary Shift in Western Siberia May Not Modify Dissolved Nutrient Concentrations in Rivers
Open AccessArticle

Spatial and Seasonal Patterns of Nutrients and Heavy Metals in Twenty-Seven Rivers Draining into the South China Sea

1
Wuhan Library and Intelligence Centre of the Chinese Academy of Sciences, Wuhan 430071, China
2
Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou 510642, China
3
Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, China
*
Author to whom correspondence should be addressed.
The first two authors contributed equally to this work.
Water 2018, 10(1), 50; https://doi.org/10.3390/w10010050
Received: 10 November 2017 / Revised: 5 January 2018 / Accepted: 7 January 2018 / Published: 10 January 2018
(This article belongs to the Special Issue Recent Progress in River Biogeochemistry Research)
Due to the acceleration of industrialization and urbanization in recent decades, the majority of coastal rivers and estuaries in China have been moderately or severely contaminated by a variety of pollutants. We investigated the spatial and seasonal variations of water nutrients (permanganate index, chemical oxygen demand, biochemical oxygen demand, ammonium, nitrate, total nitrogen, and total phosphorus) and heavy metals (Hg, Pb, Cu, Zn, Se, As, Cd, Cr, Fe, and Mn) in 27 subtropical rivers draining into the South China Sea. Our results indicated that the average concentrations of all water quality parameters except ammonium, total nitrogen, and total phosphorus satisfied the requirements for grade III of the surface water quality standard of China. The concentrations of both nutrients and heavy metals showed a strong spatial variation. Cluster analysis classified the 27 rivers into three spatial clusters corresponding to low, moderate, and high pollution levels. In terms of seasonal variation, the values of chemical oxygen demand and biochemical oxygen demand in wet seasons were significantly lower than those in dry seasons. Multivariate statistical analyses demonstrated that river nutrients might mainly originate from domestic, industrial, and agricultural wastewaters, while heavy metals likely came from industrial activities and natural weathering processes. The findings of this study suggest that for reducing the pollution of subtropical rivers draining into the South China Sea, further efforts should be made to control nitrogen and phosphorus export from catchments. View Full-Text
Keywords: nitrogen; phosphorus; source identification; trace metals; water quality nitrogen; phosphorus; source identification; trace metals; water quality
Show Figures

Figure 1

MDPI and ACS Style

Deng, A.; Ye, C.; Liu, W. Spatial and Seasonal Patterns of Nutrients and Heavy Metals in Twenty-Seven Rivers Draining into the South China Sea. Water 2018, 10, 50.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop