How do biotic and abiotic factors interact to affect populations in an ecosystem?

I think you should use an xample rather than tear into this as some kind of meaningful question.
An abiotic factor include the stuff we call "edaphics" which include soils, water, climate etc.
The biotic factors are the resultant availability if vegetation or prey for food. .
Its often called the "ecological web".

All these factors interact to allow either a great diversity of life or else (like the Serengheti) we see huge numbers of relatively few species.

Think of deserts, forests , forests edges, arctic deserts, mountainous areas, huge grasslands etc etc.