Though genuinely unsure and curious as to whether that's a separate legal (or perhaps media reporting) issue.

The first is that a lot of agricultural land is leasehold, not freehold.

The second is that below a certain depth, the Crown owns what's underground and has the right to go through your property to get to its property, whether directly or by leasing it to a mining company.

On an aside it appears Australia has done away with the self incrimination protection laws Is that a right in most democratic countries?

I’m fairly certain it’s still the case that you can’t be compelled to incriminate yourself in a court. Of course you have clearly unjust laws like those concerning the Building/Construction Commission in which an ad hoc court can compel you to give evidence against yourself, but this is an abberation which has not had the opportunity to be challenged in the High Court AFAIK, and it will likely be abolished when Labor comes back into power.

“Section 6DD of the Act provides that, where a witness is compelled by a summons to give evidence to the Royal Commission, that evidence isn’t admissible against a natural person in any civil or criminal proceedings in any court of the Commonwealth, or of a state or territory. It is, however, admissible against a corporation. ”

However, evidential immunity under s 6DD doesn’t protect clients (who have been compelled to give evidence to the Royal Commission) from a regulator, such as ASIC, using their evidence as a springboard to gather secondary or derivative evidence, and using that derivative evidence against them.