Placement of two descriptive adjectives

Placement of two descriptive adjectives
 

"This unique natural ecosystem" should be which of the following - or else what?

Este ecosistema natural único
Este ecosistema natural que es único
Este natural ecosistema único

I sort of like the third choice, but is it right?

My choice is:
este único ecosistema natural

My 2 cents:

Moving a descriptive adjective such as 'natural' from its customary position after its noun to the unusual position before the noun typically affects the perceived meaning of the adjective. Unless you are certain about what the perceived alteration in meaning is likely to be, I would avoid #3.

As for #2, there is no effective difference in meaning between 'que es único' and 'único', unless 'que es único' is extra information that is not necessary to identify the ecosystem in question. In English we would write "this natural ecosystem, which is unique, ..." (in other words, "which is unique" is wrapped in commas).

Thanks Rusty, it sounds good to me. I didn't realize único could go first in order and still carry the meaning of unique. Maybe it can when there is another adjective present, as in this case?

Ooo, I like it too. And I think único keeps its meaning essentially unchanged in either position regardless of whether another adjective is present or not. By virtue of its meaning, 'unique' is intrinsic rather than descriptive; if something is unique, there is no other, and if there is another, it cannot be unique.

Well, just to muddy the waters, placing 'único' before a noun usually means that there is only one. To me, though, this is one of the meanings of 'unique'.

So, the adjective can precede it and it means 'unique' (this one, it's the only one or there is no other like it). If your 'natural ecosystem' isn't the only one, the adjective can trail it and it means 'unique', but with the meaning of 'special'.

Thanks, guys. What great explanations! This forum is worth its weight in gold.

Este ecosistema único = This unique ecosystem
Este único ecosistema = This only ecosystem

Este singular ecosistema = This unique ecosystem
Este singular ecosistema natural = This unique natural ecosystem

While reading the thread I was also thinking in the word "singular". Perhaps some context would help choose the best option.

I'll go with singular. Thanks to all!