How do wetlands cycle nutrients through an ecosystem?

Wetlands play a critical role in nutrient cycling, often functioning as the "kidneys of the landscape" by filtering, storing, and releasing nutrients and organic materials. Their ability to cycle nutrients is largely driven by their unique environmental conditions, specifically the presence of waterlogged, anaerobic (oxygen-depleted) soils.123

Nutrient Processing and Storage

• Sinks for Nutrients: Wetlands act as important sinks for inorganic nutrients and atmospheric carbon, effectively removing them from the water column and storing them within the ecosystem.1
• Decomposition and Soil Chemistry: In saturated conditions, the lack of oxygen slows the decomposition of organic matter. This leads to the accumulation of organic soils, such as peat, where nutrients may be held for long periods.23
• Microbial Transformations: Anaerobic bacteria thrive in these oxygen-depleted environments, facilitating chemical changes that are vital to nutrient cycling. For example, in the nitrogen cycle, denitrifying bacteria are particularly active in waterlogged soils, where they convert nitrates into free atmospheric nitrogen, thereby depleting excess nitrates from the system.34
• Mineral Reduction: Bacteria also reduce elements like iron and manganese, influencing how these minerals are concentrated and moved within soil layers.3

By naturally collecting and processing these materials, wetlands help cleanse polluted waters and maintain the integrity of the broader ecosystem.1