This is particularly significant at the State level because, under provisions of the Clean Water Act and the Coastal Zone Management Act, Ohio EPA is responsible for managing wetlands in coordination with the Army Corps of Engineers, USDA's Natural Resource Conservation Service, and county and township governments. Nutrient retention by wetland soils is regulated by several physical, chemical, and biological processes. Factors include litter, sediments, anaerobic conditions and phosphorus. Vegetation, however, serves only as a seasonal sink unless the biomass is harvested. Sediment texture influences the rate of nutrient release into the water column.
Hydrological characteristics are another factor.
These factors also determine how the marsh reacts to pesticides. Conservation tillage techniques, such as leaving stubble on the ground over the winter, also has an effect. Such transfer rates can be calculated for the past 120 years by dating the sediment profiles using activities of radionuclides.