What effect does upwelling have on marine ecosystems?

Upwelling is a geological and oceanographic phenomenon that plays a crucial role in marine ecosystems. The process involves the movement of deeper, colder, and often nutrient-rich waters rising to the surface. When these nutrient-rich waters come to the surface, they provide an essential source of nutrients for phytoplankton, which are the foundational producers in the marine food web. This boost in nutrients supports an increase in primary production, which in turn supports larger ecosystems, including fish populations and other marine life.

This influx of nutrients creates a fertile environment that enhances productivity in marine ecosystems, particularly in regions where upwelling is prevalent, such as along coastlines. Such regions are known for their rich biodiversity and are often significant fishing grounds due to the abundance of life that upwelling creates. Therefore, the correct answer highlights the beneficial impact of upwelling on marine ecosystems through the availability of nutrient-rich waters.