Vlogpost: Another 40 minute walk (well, 45) in four (ish) minutes

Welcome to another walk.

   

The path I walked in this one (on Friday 13th January) lies on the boundary between Hazlemere village and the start of the Chiltern Hills Area of Outstanding Natural Beauty (AONB). Though I'll admit that I find it weird to refer to farm fields as 'natural beauty'. While I can't argue that the views are very pleasant, they're not exactly healthy. 

Ploughing is destroying the soil. 

According to the UN’s Food and Agriculture Organisation, the world, on average, has just 60 more years of growing crops. Even in Britain, which is spared the tropical downpours that so quickly strip exposed soil from the land, Farmers’ Weekly reports that we have 'only 100 harvests left'. The problem is ploughing. It smashes up the sub-surface ecosystem, which is as rich as the rainforest - but you'll never hear Sting writing a protest song on his lute about saving the mud. 

Take worms, for example. It may not be obvious, but there can be up to seven million earthworms in a hectare of unploughed soil. In fact, the weight of earthworms underneath fertile pastureland may be greater than that of the livestock grazing upon it. Tunnelling unseen, this wriggly army helps to  increase the drainage and aeration of soil when they open up channels for water and air down to the subsoil. Soil biology is also improved, since the activity of earthworms stimulate micro-organisms and actively spreads fungi and bacteria through the soil profile. This ultimately affects soil chemistry, since the availability of practically all nutrients is improved when organic matter passes through the earthworm gut. For example, the concentration of nitrates is eight times higher in worm casts than in the surrounding soil. It's hard to believe, but as much as 60 tonnes per hectare of soil passes through the digestive system of worms every year and is deposited on the surface as casts. However, turning the soil by ploughing brings the worms to the surface where they get picked off by seagulls and blackbirds (and Red Kites in these parts). One recent study showed that ploughing killed '61–68% of the earthworm biomass' in a particular set of fields. Plus the farm equipment compresses the soil, squashing the worm tunnels closed so that rain, rather than soaking in, runs off the fields taking away nutrients. So then farmers have to resort to chemical fertilisers. 

However, it's not all doom and gloom. There are experiments going on all over the world to test the idea that no-till farming (no ploughing) can produce good yields while protecting the soil. And the results are very encouraging. Ecologist Nick Haddad and colleagues from Michigan State University have been studying how land use intensity affects agriculture and environment, and the long-term agricultural and environmental effects of converting agriculture management practices from tilled to no-till. 'Every year for more than 30 years, the yield in no-till treatments increased versus the yield in tilled treatments,' Haddad said. 'I would have expected a point where the yields and economic benefits reached their peak, but they continued to rise. It was jaw-dropping.' 

No-till farming also increases biodiversity and a huge reduction in the need for pesticides and weedkillers which, at the moment, threaten our wildlife and poison our streams.

There is hope, it seems. It just takes change and change is never easy.

Meanwhile, have some bonus Red Kites.