Tropical Zodiak

I am not certain if you are using a specific astrological system when you speak of tropical zodiac, or just the general term for the southern sky?
michael

How does the Tropical Zodiak fit in with Taoist cosmology and metaphysics ?

The major Chinese system of astrology is based on direct observation, not on fixed houses of the Zodiac (which in western astrology gradually rotate out of where they are supposed to be). But they do use a cycle of twelve to describe the stellar influences on earth, and fit 28 constellations within that.
But we do need to keep in mind that there are many many different systems of Chinese and Taoist astrology. My main Taoist astrology teacher knew 18 different systems of astrology. They each focused on something different, but he claimed they all worked to one degree or another. So it is very difficult to give a conclusive answer to your question.

What level of Earth does it belong to in Later Heaven ?

The stars were considered by some Taoists to be the bodies of beings that are divine and very close to the Tao mind. They also focus on dark stars, invisible stars, the yin partners to the visible stars (which curiously, is being validated by some astronomical studies today). So they are part of Later Heaven, in the sense they are physically manifest. But stars are considered to hold the patterns of one’s spiritual (early heaven) destiny, whereeas planets held one’s worldly destiny in their patterns.

Does it correlate to the jing level or essence in humans ?

Star essence is closer to early heaven and ultimately original jing, which also exists in very subtle but difficult to grasp form within humans. So we could say that stars are here to vibrationally guide us to that level of consciousness within ourselves.
Zodiacal pattern is also imprinted into the jing, but were considered “fixed stars”, as opposed to “starry beings that move”, the planets. So it probably useful to distinguish between stars as prenatal/early heaven and planets as post natal/later heaven.
michael