Nutrient Enrichment and Oxygen Depletion

Habitats Affected:

Water column, shell bottom, SAV, wetlands, soft bottom, ocean hard bottom

Common Sources:

Wastewater discharges, nonpoint runoff from agriculture, urban areas, animal operations, and air emissions

Impacts:

• Excess nutrients fuel phytoplankton blooms in the water column, which can contribute to low oxygen events in the water column and bottom sediments, causing fish kills and mortality of fish and non-mobile invertebrates in the water column, soft bottom, or shell bottom communities.
• Reduced light availability in the water column from plankton blooms and excessive epiphytic growth impacts the ability of SAV plants to survive and grow.
• High levels of nitrogen can cause mortality of eelgrass.
• Excess nutrient loading can result in toxic blooms such as red tide or Pfiesteria outbreaks.

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