Related Experiment Video
Updated: May 22, 2026
08:49
Vegetated Treatment Systems for Removing Contaminants Associated with Surface Water Toxicity in Agriculture and Urban Runoff
Published on: May 15, 2017
Mitigating agrichemicals from an artificial runoff event using a managed riverine wetland
Richard E Lizotte1, F Douglas Shields, Justin N Murdock
1USDA-ARS National Sedimentation Laboratory, Oxford, MS 38655, USA. Richard.lizotte@ars.usda.gov
The Science of the Total Environment
|May 8, 2012
Summary
Managed riverine wetlands effectively reduce agricultural runoff contaminants like sediment, nutrients, and pesticides. These wetlands significantly decrease pollutant concentrations within 48 hours, protecting downstream river ecosystems.
Area of Science:
- Environmental Science
- Ecotoxicology
- Hydrology
Background:
- Agricultural runoff introduces sediment, nutrients (nitrogen, phosphorus), and pesticides (atrazine, metolachlor, permethrin) into aquatic ecosystems.
- Managed riverine wetlands are proposed as a solution to mitigate these pollutant loads.
Purpose of the Study:
- To assess the mitigation efficiency of a managed riverine wetland for agricultural runoff contaminants.
- To quantify the reduction of suspended sediment, nutrients, and pesticides over time and distance within the wetland.
Main Methods:
- A simulated agricultural runoff event was introduced into a 500 m long, 25 m wide managed riverine wetland.
- Water samples were collected at various distances (0-500 m) and time points (up to 28 days) post-amendment.
- Analysis included suspended solids, nitrogen, phosphorus, and three specific pesticides.
Main Results:
- Rapid attenuation of contaminants was observed; sediment, nutrient, and pesticide concentrations decreased by 79-98%, 42-98%, and 63-98% within 48 hours, respectively.
- By day 28, amendment concentrations were near pre-amendment levels.
- Pesticide concentrations at 500 m peaked at ≤11% of upstream levels and dissipated by day 28.
Conclusions:
- Managed riverine wetlands, particularly those ≥1 hectare with days-to-weeks hydraulic residence times, efficiently trap agricultural runoff.
- These systems effectively mitigate the impact of moderate rainfall events on receiving rivers by reducing contaminant loads.
Related Concept Videos
00:46Bioremediation
Bioremediation is the use of prokaryotes, fungi, or plants to remove pollutants from the environment. This process has been used to remove harmful toxins in groundwater as a byproduct of agricultural run-off and also to clean up oil spills.
02:41Responses to Drought and Flooding
Water plays a significant role in the life cycle of plants. However, insufficient or excess of water can be detrimental and pose a serious threat to plants.
01:28Microbial Bioremediation of Pesticides
Pesticides often feature structurally complex chemical architectures, incorporating halogen groups and multiple aromatic rings. These characteristics confer high chemical stability, rendering many pesticides resistant to natural degradation processes. This resistance poses significant environmental concerns, as persistent pesticide residues can accumulate in ecosystems and affect non-target organisms.Despite the inherent stability of many pesticides, certain microorganisms possess the metabolic...
01:26Microbial Bioremediation of Hydrocarbons
Bioremediation is an environmentally sustainable process that employs living organisms—primarily microorganisms—to degrade or neutralize pollutants from contaminated environments. In oil spills and hydrocarbon pollution, bioremediation involves the use of hydrocarbon-degrading bacteria to transform toxic compounds into less harmful substances. This approach leverages natural microbial metabolic processes and is considered both cost-effective and ecologically favorable compared to physical or...
01:22Net Change Theorem
The Net Change Theorem is a fundamental principle in calculus that establishes a direct relationship between a function’s rate of change and its accumulated change over an interval. Mathematically, it states that the definite integral of a function's derivative over a given interval [a,b] yields the net change in the original function:This theorem has significant applications in various real-world scenarios, including physics, economics, and engineering. A particularly useful application is in...
01:57Adaptations that Reduce Water Loss
Though evaporation from plant leaves drives transpiration, it also results in loss of water. Because water is critical for photosynthetic reactions and other cellular processes, evolutionary pressures on plants in different environments have driven the acquisition of adaptations that reduce water loss.