You will never get an authoritative unbiased scientific resource. There is no agreed measure on what 'impact' means, and whether that is positive or negative.

You will never get an authoritative unbiased scientific resource. There is no agreed measure on what 'impact' means, and whether that is positive or negative. One persons fantastic city is anothers urban blight on pristine wilderness. All published data are biased in some direction. You can measure conversion of wilderness to farmland, farmland to cities, displacement of wildlife, and many other factors. Much of the data is modelled. All of it is produced to prove one point of the other. Even when people agree on the data, they will disagree on the positive or negative impacts. The trusted third party is a mirage. All you can do is interpret the supplied data and arguments and make up your own mind.