So, you would be surprised, Chinese law itself is actually extremely comprehensive and large. I would argue that Chinese law is nearly identical in scope to most Western law. There are laws on the books enshrining freedoms, and many which allow the people to hold the state accountable. All this with the humongous caveat that courts and judges will often not enforce laws as they are written, so just because China might have stringent environmental protections on its books, getting a judge who will actually allow such cases is difficult.

The law is structured in such a way that the judges and courts have a great deal of freedom and discretion about which laws to enforce when, and can decide not to enforce laws at specific times. This is seen as a strength of the system, in that it prevents a lot of obtuse bickering over minor details of legal interpretation. The judge can do maneuvers like saying "The spirit and intent of the law was this, doesn't matter what it actually says" and this is legal. So yes the Chinese state probably does have protections for this sort of thing, but they probably never enforce any of them because of rampant abuse.