Which of these is NOT a method for managing nutrient inflows?

Constructing a dam on waterways is not typically considered a method for managing nutrient inflows. Nutrient management focuses on controlling the introduction of nutrients, particularly nitrogen and phosphorus, into aquatic systems to prevent issues such as algal blooms and eutrophication.

The other methods presented involve direct actions or strategies aimed at reducing nutrient loads. Checking for hidden nutrient sources is crucial because it helps identify all potential contributions to nutrient pollution. Leaving a 20-foot buffer for fertilization can help reduce runoff and protect water bodies from nutrient overflow. Avoiding adding fertilizers is a straightforward approach to minimizing nutrient input into the ecosystem.

In contrast, while constructing a dam may alter water flow or create a habitat, it does not directly address nutrient inflows and can, in some cases, even exacerbate nutrient issues by changing sediment and nutrient dynamics within the water system.