Which of the following is NOT a cause of problems in the Kalamazoo watershed?

Cultural tourism is not typically considered a significant cause of problems in the Kalamazoo watershed. While it can have some environmental impact, such as increased foot traffic or minor pollution from visitors, these effects are generally outweighed by the direct environmental impacts caused by other factors.

In contrast, runoff, industrial discharge, and agricultural fertilizers are all critical issues that contribute to the degradation of water quality and ecosystem health in the watershed. Runoff, particularly from urban areas, often carries pollutants such as oils, heavy metals, and sediments into water bodies. Industrial discharge can introduce harmful chemicals and waste directly into the water, often leading to severe ecological consequences. Agricultural fertilizers, when washed into rivers and streams, can lead to excessive nutrient loading, resulting in harmful algal blooms and disrupting the aquatic ecosystem.

Consequently, cultural tourism lacks the same level of direct environmental threat compared to the other options, which are well-documented contributors to watershed problems.