Dig or not to dig?

If you look at the video suggestion "A farm for the future":

http://transitionstourbridge.wordpress.com/2010/01/05/film-a-farm-for-the-future/

there is some anecdotal evidence that cultivation does seem to lower the number of beneficial micro organisms in the soil.  One of the farmers suggests that ploughing should be avoided because it seems to kill off all the valuable micro organisms.

Also there are several suggestions that digging destroys helpful mychorrhizal fungi here:

http://www.dgsgardening.btinternet.co.uk/mycorrhiza.htm

There is also a suggestion that ploughing and digging increase the decomposition of carbon in the soil adding to the carbon dioxide and methane load of the atmosphere.

I think that it is impractical to suggest that gardeners could avoid digging because we have to when cropping such things as potatoes, carrots, parsnips and many other vegetables.  Also adding carbon to the soil in the form of manure, compost, charcoal etc. will also involve digging.  When you grow green manures you have to dig them in when you need the land for crops.

When allotments are taken over they are usually in a terrible state and need clearing by digging.

However, we must take into account that we may well be destroying a community of organisms that contribute greatly to the fertility of the soil and try not to dig especially when a quick fork over or hoeing would suffice.