The thing is, it's actually a little hard to measure, because both of those things have multiple possible impacts.
Eating locally-produced, grass-fed beef probably has less total environmental impact than eating, say, kiwi fruit flown to the US from New Zealand. Obviously, eating meat once a week has less impact than eating the same amount of meat at every meal, so the first sort of omnivore would reduce their environmental impact less by eschewing meat altogether. And so on.
And deforestation isn't entirely straightforward in its impact, either. It actually *reduces* atmospheric carbon to, eg, cut down a bunch of trees, then replant them (as long as the wood is used for, eg, building, rather than just being burned or left to rot), because young, growing trees take in more CO2 than mature trees. Even slash-and-burn agriculture can be done in an environmentally sustainable way in a lot of rain forest areas... as long as the plots are small, and allowed to grow back to rainforest after they're used (eg slash-and-burn a field, plant your crop, harvest your crop, let the area regrow, come back in 20 years or something and slash and burn that field again)
I really don't know the total, worldwide figures, for the environmental impact of either meat consumption, or of unsustainable logging. And the individual-contribution figures vary wildly.