What are the ecosystems on the northernmost island of japan

I would assume you're talking about Hokkaido, the northernmost prefecture in Japan. Hokkaido's home to many ecosystems, including forests, wetlands, mountainous areas near the center, and coastal plains along the edges of the island. Many of the forests and wetlands are contained in national parks, some of which are the largest in the entire country.

The answer to the question is moraine