In fact it's a very good question. Good soil is obviously vital - 95% of our food comes from soil. Yet last December a senior UN official said that at current rates of degradation all of the world's top soil could be gone within 60 years.The official, Maria-Helena Semedo of the Food and Agriculture Organization (FAO), blamed chemical-heavy farming techniques, deforestation which increases erosion, and global warming.
This is a key concern for Greens - it's one of the ways in which human activity is overloading the planet's carrying capacity. It's no accident that the Green Party of England and Wales is the only UK party led by someone with a degree in agricultural science!
[By the way, Cameron and Miliband both read Philosophy, Politics and Economics (PPE) at Oxford. But I digress.]
So what is our policy on soil?
The whole food and farming policy is at here. Paras 630 to 639 are the most relevant.
In summary we would make a transition to a more sustainable agriculture, that is, an agriculture that does not depend on large inputs of fossil fuel energy and which improves, not degrades, soil fertility. It's not really that new. The Norfolk Crop Rotation does exactly that and was invented in the 17th century! Doubtless we can do better now.
In the UK we would:
- Support a rapid increase in the proportion of land designated as organic by providing advice and subsidies.
- Encourage a reduction in the use of synthetic fertilisers by taxing them and supporting alternative methods of retaining soil fertility, such as green manures and composting
- Support a shift towards farming systems based on perennial crops through targeted support and funding.
- Progressively remove some of the tax rebate on fuel for agricultural use.
- Fund research into the best ways of making the transition.
Looking beyond the UK we would encourage other countries to adopt similar policies and, especially, to halt the wave of deforestation and natural habitat destruction that is sweeping the tropics. Since much of that destruction is driven by our demand for the crops that replace old forests, notably oil palms, a complete solution requires all the developed countries to reduce their use of such products. That is also our policy and much more than an add-on to this one.
+++++++++++++++++++++++++++++++++++++For more information about soil see the WWF view and Fred Pearce in New Scientist on losses from salt contamination and some US Soil data.