What percent have humans activities reduced the earth's forest cover in the last 8000 years

Nearly 50%

Explanation:

The earth about 8000 years back was comprised of almost 6 billion hectares of forest-covered land. And according to the research, it has been observed that nearly 50% of the initially forest-covered region has been reduced, which has now become about 3 billion hectares.

These forests are being cut down for various purposes, such as construction of urban areas, construction of wooden houses, making furniture, overgrazing of animals, forest fire. It causes both naturally as well as due to anthropogenic activities.

Thus, nearly 50% of the forest is reduced in the last 8000 years.