That all depends on what your goals are for your land and flock management. It also depends on your climate and soil type and ground cover. Are you expecting the flocks to forage most if not all of their feed from the acre? Or are you just wanting to give them plenty of room to roam and do chicken and turkey pursuits? Do you expect the existing ground cover to stay in place... look decent? Or are you willing to have the birds turn the ground cover into a barren moon scape? I can tell you that last summer, I had a 1600 s.f. electronet run. I started with 11 chicks, sent 6 cockrels to the freezer, ending up with 5 pullets. They did a combination of ranging in the run, with free range time when I was home to supervise them. They removed all of the greenery in about a 15' radius around their coop which was in the electronet enclosure. They made some pretty deep dust baths, ate all of the vegetation that they liked, left the stuff they didn't like... So the ground cover has changed from lawn(ish) to a much coarser combination of asters, some noxious viney creeping invasive plant, and some grass. They were well fed with standard prepared feed. Your acre would be 40,000 s.f. I don't know how hard turkeys are on a yard. For my own flock management, I'm happy if the ground stays covered with green. It doesn't have to be grass. If I were terribly concerned about the types of plants growing there, I'd have to move their run, and overseed it with what ever I wanted to grow there. Fall would be a good time to do that, as the flock will be ranging in the harvested garden, and grasses germinate and put on good growth in cooler weather. The one thing I never want to see in my flock management is bare soil in my run. Sorry, that was the long answer.
Here's the short answer: You'll have to experiment and see what works for you. Perhaps you could divide that acre in half, and put chickens and turkeys in 1/2 acre to a density of 25-50 s.f./chicken, and 50-100 s.f./turkey. Then, when one section shows wear, you can move them to the other side.