Functions of Groundwater in the Earth's Critical Zone: The Interplay between Organic Matter and Microbial Communities

Dear Colleagues,

This Special Issue aims to update the knowledge on organic matter composition and biogeochemical processes in groundwater by improving the current understanding of their structure and interactions with surrounding matrix including microorganisms. Understanding the biogeochemical processes that govern groundwater in the deep critical zone is expected to improve the current understanding of groundwater’s origins, bioavailability, and chemical composition, which is relevant to both coastal and inland communities. Groundwater stores the majority of liquid fresh water on Earth and is a major source of water for human consumption and agriculture. Organic matter in groundwater is known to play a very important role in biogeochemical groundwater reactions. However, its concertation and the flux of organic carbon in the deep critical zone are influenced by recharge and abstraction, and surface and subsurface processing. While many investigations have studied the transport and reactivity of inorganic ions within groundwater, considerably less is known about the sources, composition, and bioavailability of organic matter in groundwater. This research will shine the light on groundwater organic matter processing and transport pathways, including groundwater river mixing.

We welcome original research, methods, opinions, reviews, and perspective articles focused on studies investigating:

• The biological activity of organic matter in groundwater through evaluation of their mode of action throughout different seasons, and different surface processes;
• The development and application of innovative chemical and physical techniques to characterize the molecular structure and function of organic matter in groundwater;
• Biotic and abiotic factors that influence organic matter processing in groundwater;
• Biogeochemical processes governing the flow of groundwater to streams, lakes, rivers, wetlands, and costal environments.

Prof. Dr. Malak Tfaily
Guest Editor

Manuscript Submission Information

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Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

• organic matter
• organic carbon
• analytical methods
• groundwater
• river water mixing
• biotic and abiotic processes
• bioavailability
• microbes