There isn't one specific term for someone who studies both living and non-living things in an ecosystem. However, depending on the specific focus of their study, there are a few possibilities:

* Ecologist: This is the most general term. Ecologists study the interactions between living organisms and their environment, including both biotic (living) and abiotic (non-living) factors.

* Environmental Scientist: This term encompasses a broader range of disciplines, including the study of how human activities impact the environment. They might focus on factors like pollution, climate change, and resource management, which involve both living and non-living components.

* Ecosystem Scientist: This term emphasizes the study of whole ecosystems, including all their components, both living and non-living.

* Biogeochemist: This specialist focuses on the interactions between living organisms and the chemical cycles of the Earth, which includes both biotic and abiotic components.

Ultimately, the most accurate term would depend on the specific area of study and the research focus.