I have searched the web for a while now and can't get an answer to this. Can anone tell me what exactly you can do with agricultural land. Can I build a structure less than 40m squared? Can I have a mobile business on it? Can I have any type of farm on it? Where can I get guidelines for it? Do planning permission rights change with time and why? If there is a river running through it, do I have the rights to that water and can I collect it?