What role do mangroves play in an ecosystem?

Mangroves are often referred to as a keystone species due to their significant role in coastal ecosystems. They provide essential habitat for a diverse array of marine and terrestrial species, serving as nursery grounds for fish and other aquatic organisms. Their complex root systems stabilize shorelines, reducing erosion and protecting coastal areas from storm surges and flooding.

Beyond their structural contribution to the ecosystem, mangroves also play a vital role in nutrient cycling. They contribute organic material to the food web when leaves fall and decompose, thus supporting a wide range of organisms that depend on mangroves for food and shelter. Additionally, their ability to sequester carbon makes them crucial in combating climate change.

The other options do not accurately reflect the ecological role of mangroves. While they are involved in filtering and trapping sediments, this does not classify them as a primary consumer or a filter for freshwater in the way presented in the choices. The promotion of invasive species is generally seen as a negative impact on native ecosystems, which does not apply to the beneficial roles that mangroves fulfill.