From 1982 to 2016, how much of the world's net tree coverage was lost?
From 1982 to 2016, the world's tree coverage actually increased. Per a 2018 paper in journal Nature: "Here we analyze 35 years' worth of satellite data and provide a comprehensive record of global land-change dynamics during the period 1982-2016. We show that ... tree cover has increased by 2.24 million sq. km (+7.1% relative to the 1982 level)." The authors of the paper calculated that the best estimate of 7.1% varies from a 2.9% to 10.8% rise with 90% confidence.