Related Experiment Video
Updated: Jun 23, 2026
13:48
Design and Construction of an Urban Runoff Research Facility
Published on: August 8, 2014
13.0K
Transport Pathways of Nitrate in Stormwater Runoff Inferred from High-Frequency Sampling and Stable Water Isotopes
Jian Wang1,2, Xiao Li1, Yan Li3
1State Environmental Protection Key Laboratory of Soil Health and Green Remediation, Huazhong Agricultural University, Wuhan 430070, China.
Environmental Science & Technology
|August 17, 2024
Summary
Storm events move nitrogen from land to streams, primarily through shallow subsurface water. Nitrate was the dominant nitrogen form during storms, impacting aquatic ecosystems.
Area of Science:
- Environmental Science
- Hydrology
- Geochemistry
Background:
- Storm events mobilize landscape nitrogen into streams, causing eutrophication.
- Nitrogen transport pathways and storm responses are not fully understood.
- Agricultural catchments are significant sources of nitrogen pollution.
Purpose of the Study:
- To identify nitrogen sources in stormwater runoff.
- To determine nitrogen transport pathways during storm events.
- To analyze the influence of antecedent conditions on nitrogen loads.
Main Methods:
- High-frequency chemical and isotopic sampling.
- Bayesian mixing modeling to partition runoff sources.
- Quantification of nitrogen forms (TN, TDN, NO3-N) and water flux.
Main Results:
- Shallow subsurface water was the dominant source (74%) of runoff and nitrogen (72-79%).
- Groundwater contributed 11% of runoff and 17-22% of nitrogen.
- Nitrate (NO3-N) was the predominant nitrogen form during storm events.
Conclusions:
- Shallow subsurface flow is a key pathway for nitrogen transport during storms.
- Understanding nitrogen sources and pathways is crucial for managing aquatic pollution.
- Results inform catchment management strategies to reduce nitrogen loads.
More Related Videos
07:14Automated, High-resolution Mobile Collection System for the Nitrogen Isotopic Analysis of NOx
Published on: December 20, 2016
11.6K
08:05Measurement of the Potential Rates of Dissimilatory Nitrate Reduction to Ammonium Based on 14NH4+/15NH4+ Analyses via Sequential Conversion to N2O
Published on: October 7, 2020
6.1K
Related Concept Videos
01:49The Nitrogen Cycle
Nitrogen atoms, present in all proteins and DNA, are recycled between abiotic and biotic components of the ecosystem. However, the primary form of nitrogen on Earth is nitrogen gas, which cannot be used by most animals and plants. Thus, nitrogen gas must first be converted into a usable form by nitrogen-fixing bacteria before it can be cycled through other living organisms. The use of nitrogen-containing fertilizers and animal waste products in human agriculture has greatly influenced the...
01:20Overview of Nitrogen Metabolism
Nitrogen is a very important element for life because it is a major constituent of proteins and nucleic acids. It is a macronutrient, and in nature, it is recycled from organic compounds and stored in the form of ammonia, ammonium ions, nitrate, nitrite, or nitrogen gas by many metabolic processes. Many of these metabolic processes are carried out only by prokaryotes.
The largest pool of nitrogen available in the terrestrial ecosystem is gaseous nitrogen (N2) from the air, but this nitrogen...
The largest pool of nitrogen available in the terrestrial ecosystem is gaseous nitrogen (N2) from the air, but this nitrogen...
01:15Metabolism of Chemolithotrophs
Chemolithotrophs are microorganisms that obtain energy by oxidizing inorganic molecules such as hydrogen gas (H₂), ammonia (NH₃), reduced sulfur compounds (H₂S, S²⁻), and ferrous iron (Fe²⁺). Unlike heterotrophic organisms that rely on organic carbon, chemolithotrophs transfer electrons from these inorganic donors to the electron transport chain (ETC), generating a proton motive force (PMF) that drives ATP synthesis through oxidative phosphorylation. However, because inorganic electron donors...
01:22Inorganic Nitrogen Assimilation
Nitrogen is an essential element in biological systems, forming a crucial component of proteins, nucleic acids, and other cellular constituents. Many bacteria and archaea acquire nitrogen in the form of nitrate (NO₃⁻) or ammonia (NH₃), which are then assimilated into biomolecules through specific enzymatic pathways.Assimilatory Nitrate ReductionWhen nitrate enters the cell, it undergoes a two-step reduction process known as assimilatory nitrate reduction. Initially, the enzyme nitrate reductase...
01:26Microbes and the Nitrogen Cycle
The nitrogen cycle is a complex biogeochemical process critical to maintaining the balance of nitrogenous compounds in ecosystems. This cycle involves multiple microbial-mediated transformations through which nitrogen changes oxidation states, supporting essential ecological functions and contributing to plant and microbial growth.Nitrogen Fixation and AmmonificationNitrogen fixation initiates the cycle by converting inert atmospheric nitrogen (N₂) into bioavailable ammonia (NH₃), a process...
01:30Microbial Wastewater Treatment
Microbial communities in aquatic ecosystems play a key role in the natural breakdown of contaminants introduced through domestic and industrial effluents. Acting as biological catalysts, these microbes change and mineralize a wide range of organic and inorganic pollutants under different redox conditions.In oxygen-rich surface waters, aerobic heterotrophs lead organic matter breakdown, using oxygen as the terminal electron acceptor to efficiently oxidize substrates to carbon dioxide and water.