Long-term study shows impact of humans on land

Michael Barton Now researchers from Arizona State University are reporting on a 10-year project that studies the long term effects humans have had on the land - and the consequences for the communities whose livelihoods depend on those lands. The found that there are thresholds that separate success and failure and that current practices will increase our problems, but if you go beyond the threshold every disaster will strike. They also found that farmers can't equally cultivate crops and herd animals successfully. Lastly, they found that human activities directly effect the natural landscape.