Dr Alan Rae is chairman of a family horticultural business in East Sussex. It specialises in selling plants and gardening sundries online and grows organic vegetables for the local market in two acres of glasshouses near Lewes.
The wet conditions of the last year have had many of us wondering about the impact on the state of the soil. This concern ranges all the way from those who believe in making sure the soil is covered at all times with green manure, up to the government-funded research agencies which are running workshops on how to conserve water and nutrients.
I’ve noticed an increasing concern about the state of the soil over the last couple of years – when you have the then government chief scientist talking about it on the Today Programme you know that there must be some real concern.
I’ve recently been doing some research for an educational panel about the soil for the Linklater Pavilion in Lewes and I’ve unearthed a couple of points that should give us all food for thought.
Firstly the rate of soil formation is really slow – it works out at around 0.2 tonnes per hectare per year. By contrast we lose soil at the rate of one to 40 tonnes per hectare per year. As a for instance, one third of the soil that was on the North American continent when Columbus arrived is now at the bottom of the sea.
So you can see why there’s concern.
The more organic matter there is in the soil the better it buffers water, with each additional 1% increases the water holding capacity by 168 cu m per hectare. So the additional 5% that organic farmers use is worth around 800 cu metres per hectare reducing run off and increasing yields in drought conditions.
So what is the official view?
The BBSRC (which deals with bio science and food security) and the NERC, which focuses on environmental research, are putting together a £7m collaborative research programme of which 10% will be put up by large commercial companies to look at some of the issues involved in use of water and nutrients (how do they stay put instead of being leached out) in a more sustainable way in mainstream agriculture.
The topics chosen for evaluation for some basic research seem very much taken from an organic grower’s wish-list:
- Understanding soil flora and fauna and how soil biodiversity contributes to nutrient uptake
- In particular understanding the role of mycorrhiza and other symbionts so as to optimise soil resilience
- Re-integrating arable and livestock farming to recycle nutrients more effectively
- Gaining a better understanding of how organic matter in the soil buffers water retention
- To what extent to crops ACTUALLY need irrigating for optimum performance
- Plant breeding to create genotypes able to use nutrients and water more efficiently and generally promote resilience to a more variable climate.
What is exciting is the marrying of these “organic” approaches to the information unlocked by “big data” – precision application of fertiliser is already well established but what we have yet to secure is the benefits of understanding on a macro level how water behaves and how its flow and retention correlates with the soil structure.
A detailed understanding of this, it is argued, would greatly facilitate our ability to take action to increase resilience.
One barrier to this raised by some of the academic speakers is the progressive privatisation of access to publicly funded data which has been going on since the early ‘80s. However it will be interesting to see how this is addressed. If you would like to access the papers from this event, they are publicly available at http://www.bbsrc.ac.uk/news/events/1302-sustainable-ag-club-workshop.aspx
The research councils are currently in discussions to refine a final agenda for research – this should be available in May 2013-04-25.