Does believing in a rich spiritual aspect of life preclude atheism?

No, not if by atheism you mean a refusal to believe in magical beings.

I would rather have questions that can't be answered than answers that can't be questioned.
Richard Feynman
To me this is more agnostic than athiest. Acknowledgement of mysteries without forcing them into boxes of explanation.

@BenPike, There's a dispute on this site about the definition of atheism, but in a nutshell the dictionary definition is "disbelief or lack of belief in God or gods." This includes the agnostic position. I'm not going to engage in debate about definitions — not that I think you're attempting that — but the definition "lack of belief" is what I use and what the American Atheists use. I can go into detail about where I see overlap and distinction between atheism and agnosticism, but I don't want to distract from the current topic. I focused on what you said about not knowing how life, the world, etc., couldn't have a spiritual component because there are things we don't know or understand — but I missed the exact wording you had used directing your question at those who believe there to be no spiritual aspect, so my answer was incomplete. What I'd say here is that believing something to not be the case isn't always an entirely faith-based claim, but it is an active claim and therefore requires justification. I'd say that I don't claim to know there's no spiritual existence (though we'd need to discuss what is meant by "spiritual" and the scope of its influence in our physical world) but neither do I believe it to be a 50-50 proposition. The world appears to work according to specific principles that we can understand using the scientific method and mathematics, and looking back at history to see what we didn't know at various times and how we learned and pushed beyond our ignorance over the years has revealed a pattern of physical discovery that continually eliminated magical sources as the answer. So I don't have certainty about a spiritual aspect, but I see no evidence and I see a pattern of discovery that suggests it's unlikely as a real-world aspect. But I will adamantly disagree that because we don't understand everything then a spiritual component is necessary. That's the god-of-the-gaps argument, i.e., the claim that an assertion must be true because we have no other explanation. I consider the claim of a spiritual reality itself to be ill-defined and to offer no real answers about the world, so in such matters I'm a de facto atheist and non-spiritualist because the burden of evidence has not been met — and because throughout history science has advanced our understanding of the world's mysteries, I actively disbelieve the claim of a spiritual aspect is a necessary actor in our reality. I don't claim to know these things are impossible, but it seems unlikely based upon our experience with the world and our understanding of history. And, if such evidence is eventually forthcoming, I'll happily update my worldview.

resserts That totally makes sense even though it doesn't work for me.
Knowledge and mystery became irrevocably mingled when my Physics prof explained that if he stood in front of the class and dropped his text book enough times, it would eventually fall up, not down. Quantum theory and relativity contradict one another. Parallel universes are gaining credence as valid scientific theory. It's all one big chaotic mess.

@BenPike, I guess I'm just confused, then, by the word "spiritual" in this context. It sounds like you're still talking about physical principles, regardless of whether we fully understand them yet, and maybe I just don't have a ballpark understanding of what you're presenting as your argument. Can you give me a brief description of how you define or conceptualize spiritual aspects of the world? I don't want to argue against a position that you aren't presenting.

If you'd accept a challenge it would be to live mostly alone in some isolated area of wilderness for a week at least, and see if that works.