Radon-222 is very concentrated in groundwater relative to surface waters and thus serves as an effective groundwater discharge tracer. We observed spikes in radon data from an earlier (2004) survey of the Chao Phraya River that appeared to correspond to locations where major canals ("klongs") enter the river. We returned in 2006 and conducted more detailed surveys along some of the main klongs on the western (Thonburi) side of the Chao Phraya to evaluate this possibility. Our results show that both radon and conductivity are enriched in some areas of the klongs with 3 apparent "end-members," two of which are likely related to groundwater seepage. Furthermore, nutrient analyses conducted during a time-series experiment at a site of suspected high discharge (Wat Intharam, Klong Bangkok Yai) showed that dissolved inorganic nitrogen (DIN) and phosphate correlated significantly to the groundwater tracer, radon. Rough estimates of the nutrient fluxes in this area are orders of magnitude higher than those measured in coastal settings and may represent a significant fraction of the riverine flux. It thus appears very likely that seepage of shallow groundwater is an important pathway for nutrient contamination of the klongs, and thus to the river, and ultimately to the Gulf of Thailand.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.scitotenv.2008.11.006DOI Listing

Publication Analysis

Top Keywords

nutrient contamination
8
surface waters
8
chao phraya
8
groundwater
5
underground sources
4
nutrient
4
sources nutrient
4
contamination surface
4
waters bangkok
4
bangkok thailand
4

Similar Publications

Arbuscular mycorrhizal fungi mitigate cadmium stress in maize.

Ecotoxicol Environ Saf

January 2025

State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, and College of Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, China; School of Agriculture and Environment, and The UWA Institute of Agriculture, The University of Western Australia, Perth, WA 6009, Australia. Electronic address:

Soil cadmium (Cd) pollution poses a significant environmental threat, impacting global food security and human health. Recent studies have highlighted the potential of arbuscular mycorrhizal (AM) fungi to protect crops from various heavy metal stresses, including Cd toxicity. To elucidate the tolerance mechanisms of maize in response to Cd toxicity under AM symbiosis, this study used two maize genotypes with contrasting Cd tolerance: Zhengdan958 (Cd-tolerant) and Zhongke11 (Cd-sensitive).

View Article and Find Full Text PDF

Warfare under the waves: a review of bacteria-derived algaecidal natural products.

Nat Prod Rep

January 2025

School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Victoria 3010, Australia.

Covering: 1960s to 2024Harmful algal blooms pose a major threat to aquatic ecosystems and can impact human health. The frequency and intensity of these blooms has increased over recent decades, driven primarily by climate change and an increase in nutrient runoff. Algal blooms often produce toxins that contaminate water sources, disrupt fisheries, and harm human health.

View Article and Find Full Text PDF

Water quality assessment of Johor River Basin, Malaysia, using multivariate analysis and spatial interpolation method.

Environ Sci Pollut Res Int

January 2025

Center for Environmental Sustainability and Water Security (IPASA), Research Institute for Sustainable Environment (RISE), Universiti Teknologi Malaysia, 81310, Johor Bahru, Johor, Malaysia.

In the Johor River Basin, a comprehensive analysis was conducted on 24 water environmental parameters across 33 sampling sites over 3 years, encompassing both dry and wet seasons. A total of 396 water samples were collected and analyzed to calculate the Water Quality Index (WQI). To further assess water quality and pinpoint potential pollution sources, multivariate techniques such as principal component analysis (PCA) and cluster analysis (CA), alongside spatial analysis using inverse distance weighted (IDW) interpolation, were employed.

View Article and Find Full Text PDF

Reuse of reclaimed wastewater (RWW) in agriculture represents one of the key strategies to promote for reducing the pressures on water sources, as also fostered by the EU governance. Indeed, the European Regulation 741/2020 on water reuse, entered into force in 2023, was issued with the aim to extend the reuse of treated water in agriculture under safe conditions. It establishes the minimum quality requirements; it also foresees the possibility to add additional requirements, especially for contaminants of emerging concern (CECs), based on "scientific evidence" and the risk assessment.

View Article and Find Full Text PDF

A biochar selection method for remediating heavy metal contaminated mine tailings.

Int J Environ Sci Technol (Tehran)

April 2024

Pacific Ecological Systems Division, Center for Public Health and Environmental Assessment, U.S. Environmental Protection Agency, Corvallis, OR 97333-4902, USA.

Approximately 390,000 abandoned mines across the US pose considerable, pervasive risks to human and environmental health; world-wide the problem is even greater. Lime, organic materials, and other amendments have been used to decrease metal bioavailability (e.g.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!