What are the potential ethical dilemmas associated with the colonization of Mars?

As technological advancements bring the idea of colonizing Mars closer to reality, various ethical considerations emerge. From the treatment of any potential microbial life forms to the implications of extending human activity to another planet, there are numerous issues to examine. What are the moral responsibilities of human settlers with regards to preserving Martian environments, and how should questions around the exploitation of Martian resources be addressed? Delving into these quandaries can help shape guidelines and regulations that ensure the responsible expansion of human civilization beyond Earth.