If sludge is applied to meet nitrogen needs over several years, what future management issue may arise?

Applying sludge to meet nitrogen needs can lead to phosphorus accumulation in the soil over time. This occurs because sludge, which often contains not just nitrogen but also significant amounts of phosphorus, can reduce the nutrient balance in the soil if applied repeatedly.

When nitrogen is applied, the crops may use that nutrient efficiently, but the excess phosphorus does not get utilized to the same extent, leading to an increase in soil phosphorus levels. Over time, high phosphorus levels can contribute to environmental issues, such as nutrient runoff into waterways, which enhances the risk of eutrophication and leads to water quality degradation.

Monitoring and managing phosphorus levels is important in nutrient management practices to prevent negative impacts on both soil health and surrounding ecosystems.