There isn't one specific term for a scientist who studies rainforests. The field is broad, and scientists working in rainforests could have various specializations. Here are some possibilities:

* Tropical Ecologist: This is a general term for someone who studies the ecology of tropical ecosystems, which includes rainforests.

* Tropical Botanist: Focuses on the plant life of tropical regions, including rainforests.

* Tropical Zoologist: Focuses on the animal life of tropical regions, including rainforests.

* Rainforest Biologist: This is a broad term encompassing anyone studying living organisms and their interactions within rainforests.

* Conservation Biologist: Works to protect rainforest ecosystems and the species that live within them.

* Primatologist: Studies primates, many of which live in rainforests.

* Entomologist: Studies insects, which are incredibly diverse and abundant in rainforests.

* Herpetologist: Studies amphibians and reptiles, many of which call rainforests home.

You could also describe a rainforest scientist by their specific research area, such as "a rainforest plant physiologist," "a rainforest soil scientist," or "a rainforest climatologist."

Ultimately, the best way to describe a rainforest scientist is to specify their field of study.