How does organic farming affect climate change?

Part two of this pertinent email question - and the topic on everyone's mind - climate change.

I dont have an axe to grind here, but as a farmer, I know that I am part of an industry that will be VERY heavily affected by both climate change and peak oil. And agriculture is also a heavy contributor to it. It is estimated that food production, distribution and preparation contribute 30% of global greenhouse emissions. However numerous studies have shown that CO2 emissions from organic farming are 40-60% lower per hectare than for conventional farming systems.
There's so much debate in this area that I can only point out some of the factors that may contribute to this:
1. The production of artificial chemicals and fertilisers is energy intensive. It takes as much energy to produce a tonne of fertilisers as it does to produce a tone of steel. This fact was brought to my attention by a supplier of a unique alternative to artificial fertilisers - a product called "Twin N" which is a nitrogen fixing bacteria naturally occurring in the Amazon and which has been isolated and "farmed" for use on organic and biological farms - with almost no carbon footrint. The use of compost, recycled waste and non-genetically engineered biological fertilisers is central to organic farming.
2. The killing of soil life is also the burning out of soil carbon. Organic farms by definition depend on soil carbon to remain viable. If they do not conserve organic matter and slowly build the organic carbon of the soil they will not produce crops beyond the conversion period. Our soil organic matter has triple since we have been using organic farming methods ond conserving soil, thus sequestering many tonnes of carbon from the atmosphere. Our annual organic audit takes this into account to make sure we are viable and sustainable. Burning of crop residues is also still practiced in my part of Australia - but it is not permitted in organic systems.
3. The industrialisation of farming is energy intensive. Massive sheds sull of birds under lights, or feedlots where cattle are fed grain rations for up to 500 days until they are too fat and unhealthy to stand up if they fall over... This is the style of agriculture that is both inhumane, wasteful of resources, and unhealthy for animals and consumers. It is not natural for cattle to eat grain rations carted from hundreds of kilometres away - they should be out eating pasture. My own experience with feedlot manure is that it has an aweful smell and does not compost properly - and I bet that feedlotted animals also release more methane. Feedlots are not permitted in organic farming.
4. Organic food is often over-packaged and transported excessive distances by centralised supermarket distribution systems. This is a down side which can be reduce by wise consumer decisions at point of sale. Organic standards stipulate a preference for recylclable or renewable packaging, but this is not heavily enough enforced. In the UK transport is now being considered, with most airfreighted fruit and vegetables now no longer eligible for organic status.

All the above considered, we beleive that the federal governments support of more intensive, chemical dependent and genetically engineered agriculture is a step in the wrong direction for our future climate.