Freeze–thaw cycling, moisture and leaching from a Controlled Release Nutrient source

Controlled Release Nutrient sources assist in the bioremediation of hydrocarbon spills by stimulating microbial activity. However, freeze–thaw activity might result in splitting of fertilizer pellets with the uncontrolled release of nutrients. We examined the role of freeze–thaw and three moisture levels on nutrient release from MaxBac®, a nitrogen and phosphorus-based fertilizer encapsulated by an organic resin. We found that moisture alone accounts for most of the nutrient release, while freeze–thaw creates only a minor enhancement of nutrient release. This Controlled Release Nutrient source appears to be suitable for use in areas of freezing ground.