Learn Italian: C'è un ecosistema, il quale l'inquinamento va inesorabilmente devastando. - There is an ecosystem, which pollution is inexorably devastating.

Both constructions use a continuous tense, but they carry different nuances. While stare + gerund (like sta devastando) simply means an action is currently happening, andare + gerund adds the idea of a gradual, progressive, or step-by-step action. Here, va devastando emphasizes that pollution is ruining the ecosystem little by little over time.

Why use il quale here instead of the simpler che?

In Italian, che is the most common relative pronoun for direct objects. However, il quale can be used as a stylistic, more formal alternative. It has the advantage of showing gender and number (masculine singular, agreeing with un ecosistema). While this can help avoid ambiguity in complex sentences, here it is primarily used to elevate the register and make the sentence sound more literary.

In the clause il quale l'inquinamento va inesorabilmente devastando, which noun is the subject?

L'inquinamento (pollution) is the subject doing the devastating, and il quale (which, representing the ecosystem) is the direct object receiving the action. In Italian relative clauses, it is perfectly normal for the object pronoun to come first, followed immediately by the subject.

Is it standard to put the adverb inesorabilmente right in the middle of the verb phrase?