Characterisation of shallow groundwater dissolved organic matter in aeolian, alluvial and fractured rock aquifers

Dissolved organic matter (DOM) in both high As groundwater and low As groundwater were sampled from the Hetao basin and characterized by FT-ICR-MS for OM molecular characteristics. Results show that the greater number of molecular formulas was identified in DOM of high As groundwater (5125), compared to the number in DOM of low As groundwater (3603). Among them, lignins and aromatic structures were the most abundant compounds in both high As groundwater and low As groundwater, with 4434 formulas and 2944 formulas identified, respectively. The number of biodegradable compounds (aliphatic/proteins, lipids, and carbohydrates) was less in high As groundwater (197) than that in low As groundwater (279). Higher proportion of lignins and aromatic structures (86.5%) would lead to complexation between As and DOM, which enhanced As mobility. On the other hand, higher proportion of lignins and aromatic structures and lower proportion of bioavailable compounds in high As groundwater supported the hypothesis that more bioavailable compounds were consumed and resulted in the enrichment of lignins and aromatic structures and As release into groundwater.

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Interaction and coexistence characteristics of dissolved organic matter with toxic metals and pesticides in shallow groundwater

Environmental Pollution ◽

10.1016/j.envpol.2019.113736 ◽

2020 ◽

Vol 258 ◽

pp. 113736 ◽

Cited By ~ 4

Author(s):

Xiao-Song He ◽

Ya-Li Zhang ◽

Zhen-Hai Liu ◽

Dan Wei ◽

Gang Liang ◽

...

Keyword(s):

Organic Matter ◽

Dissolved Organic Matter ◽

Toxic Metals ◽

Shallow Groundwater

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Effects of Prescribed Burn on Nutrient and Dissolved Organic Matter Characteristics in Peatland Shallow Groundwater

Fire ◽

10.3390/fire3030053 ◽

2020 ◽

Vol 3 (3) ◽

pp. 53

Author(s):

Julia Orlova ◽

David Olefeldt ◽

Jonathan H. Yasinski ◽

Axel E. Anderson

Keyword(s):

Organic Matter ◽

Dissolved Organic Matter ◽

Inorganic Nitrogen ◽

Shallow Groundwater ◽

Nutrient Concentrations ◽

Prescribed Burn ◽

Prescribed Burns ◽

Monitoring Wells ◽

Organic Matter Concentration ◽

Before And After

Wildfires are a common disturbance in boreal regions and have the potential to affect the waterborne export of organic matter and nutrients from burned catchments. To understand the effect of fire on shallow groundwater chemistry in a forested peatland in northern Alberta, Canada, shallow groundwater monitoring wells were sampled before and after a prescribed burn. The samples were collected from control and treatment wells between May and August 2019. The results indicate no differences in dissolved organic matter concentration and chemical composition between wells in burned and unburned sections but substantially increased nutrient concentrations were found in the burned section. Here, the levels of phosphorus increased and did not return to pre-fire levels at the end of the monitoring period, while the levels of inorganic nitrogen increased and returned to pre-fire levels within a few months. With increasing wildfire activity, or as a result of prescribed burns in the Boreal Plains, we may see implications for downstream water quality, including lake trophic status.

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