In fact no. Bigger heavy machines do less damage than smaller ones overall. You have to look at the whole field, not just where the tires touch. Where the tires touch the ground the heavy machine is worse, but the smaller machines touch the ground in a lot more places and so do more damage.
Farmers are now using GPS to ensure all the tires that touch the field drive exactly the same place every pass, every year. Where the tires touch the ground is hardly worth farming, but the rest of the ground is undisturbed and so much healthier.
> smaller machines touch the ground in a lot more places an so do more damage.
That’s certainly possible but not a given, and I think the somewhat obvious implicit suggestion was to use smaller machines with a lower weight to surface area ratio, no? Damage isn’t a function of how many places the ground is touched at all, it’s only a function of weight per unit area.
Is it possible we could design small robots that weigh less per unit area than the large tractors? Sure, why not? We could have smaller machines with bigger tires, we could design machines with weight reducing features like propellers, we can choose to use lighter weight materials & designs for machine frames & engines. It seems like there a plenty of possibilities that are not in fact impossible.
The function multiples weight by a very small factor though, so area dominates. (I have no idea what the function is, I've just had conversations with soil experts who tell me this)
What area? What weight? We need specifics in order to make claims one way or the other. It’s not just possible, but easy to design machines with lower weight to surface area ratio, so it’s just wrong to conclude the answer to the question can do we better is somehow no.
You can get a phd answering this question, something I do not have. What I have done is talk to such phd's - 5 years ago. I'm not giving more details because I don't remember more. I remember this much because it stood out to me as so non-obvious.
Farmers are now using GPS to ensure all the tires that touch the field drive exactly the same place every pass, every year. Where the tires touch the ground is hardly worth farming, but the rest of the ground is undisturbed and so much healthier.