Overpopulation is (apparently) not the Problem

Here is an article that appeared in the Opinion Pages of the NY Times, byErle C. Ellis, associate professor of geography and environmental systems at the University of Maryland:

'Overpopulation is not the Problem'

'There is no environmental reason for people to go hungry now or in the future. There is no need to use any more land to sustain humanity – increasing land productivity using existing technologies can boost global supplies and even leave more land for nature – a goal that is both more popular and more possible than ever.

The only limits to creating a planet that future generations will be proud of are our imaginations and our social systems. In moving towards a better Anthropocene, the environment will be what we make it"

source: www.environmentalgraffiti.com

My question is would it really be a better Anthropocene, one where we have altered the natural environment beyond recognition just to satisfy our own growing needs? He says we can continue without using more land, but how much more productivity can we squeeze out of the land we already currently use? We've already had the Green Revolution, we already employ spectacular technology and genetics to get that bit extra per hectare and we already dowse our crops in fertiliser and pesticide. I don't understand how, in the context of a growing population and a growing number of consumers, one could think we wouldn't need more resources and more land.