Georgia is losing farmland fast. Is a state conservation fund enough to save it?

"The landowner can continue farming, growing and harvesting timber, or however else they use their land."

This isn't exactly true. The land trusts can dictate the use of the land to some degree, depending on their terms. Changes to the land such as a gravel driveway (a non-permeable surface according to them) or a new barn could require approval from the trust.