Select Committee on Environment, Food and Rural Affairs Written Evidence

Memorandum submitted by the Soil Association (U27)


    —  The Government's figures for the agricultural emissions of greenhouse gases (GHG) should include indirect sources (4-6).

    —  In particular, the impact of fertiliser use must be recognised as this accounts for 54% of agriculture's use of energy (7-10, 38).

    —  Past and on-going declines in soil carbon levels due to changes in agricultural practices must be quantified (12-18, 38).

    —  The current focus on the role of soil cultivation is misleading. The abandonment of organic matter as the base of agriculture, the increase in ploughing depth, and the increase in livestock densities need to be considered (14-18).

    —  The role of agricultural soils in atmospheric methane levels needs recognising (19-20).

    —  The impacts of food and feed miles need quantifying and including in the impacts of agriculture and national inventories (21-22, 38).

    —  Organic farming has many major proven benefits for climate change policy including a 50% reduction in energy efficiency per unit of food and substantial soil carbon sequestration potential (23-30, 37).

    —  The role of energy crops needs reassessing as the environmental impacts may not be positive (31-33).

    —  Localised food economies need to be promoted, and the current policy barriers to their development need removing (34, 38-39).

A.  Introduction

  1.  The Soil Association is the main certifier and promoter of organic food and farming in the UK. The founding objectives of organic farming are environmental sustainability and the production healthy food. Organic farming accounts for 4% of UK farmland and the UK organic food market is now worth over £1 billion, of which the Soil Association certifies about 70%. Localised food economies are also a goal of the organic movement, and the Soil Association has a department dedicated to the development of local food economies around the UK.

  2.  Scientific evidence shows that organic farming is by far the most sustainable farming system that is also applicable through the country. Considerable research in recent years has shown a range of environmental benefits—Defra have published a major paper setting these out. Because of its benefits the Government has committed to expanding organic farming. An increase in the area of organic farming is one of the Government's "quality of life" indicators. A Defra action plan for the development of organic farming was adopted in summer 2002. This includes a Government's target for 70% of the organic market to be supplied by UK farmers by 2010 (up from 35%), and for public food procurement to involve the purchasing of organic food.

  3.  In this evidence, we concentrate on the agricultural impact on climate change, which is an area that we are currently researching. We would appreciate the opportunity to give oral evidence to the committee to discuss the significance of the issues we raise, by which time we also expect to have progressed our research.

B.  Estimates of the Agricultural Contribution to Climate Change

  4.  We believe that the Government's figures for the contribution of agriculture to climate change should include the emissions from all major sources, including indirect as well as direct sources. This is not currently the case, which is very misleading to the public and industry and unhelpful for policy-making.

  5.  The UK Climate Change Programme says the total GHG emissions from agriculture, land use and forestry in 1990 were c. 12% (24.8 million tonnes of carbon) of the UK's total GHG emissions (212 MtC). As land use change contributed 8.7MtC, and as forestry was a net absorber of CO2, we assume that agriculture accounted for the rest, around 7.5% of total UK GHG emissions. However, apparently all the indirect use of energy in agriculture has not been included in this.

  6.  There is a particular problem with the CO2 estimates. The UK Climate Change Programme says that the UK's total carbon dioxide emissions in 1990 were 168MtC. The Defra report, "Climate Change and Agriculture in the UK" states: "Fossil fuel and lime use on farms accounts for less than 1% of UK emission of CO2 in 1990, though the sector also contributes to CO2 emissions through soil cultivation and indirectly through demand for manufactured fertiliser and transport of agricultural goods". These omissions are very significant contributions and directly affected by agricultural policies and industry developments. We urge the EFRA committee to advise Defra to ensure that their official emission figures for agriculture include all of the following important indirect sources.

GHG emissions from the manufacture of fertilisers

  7.  Our greatest concern with the UK's climate change policy in the field of agriculture is that the single most important factor is being ignored: the impacts of fertiliser use.

  8.  As it excludes indirect sources, the Government's "less than 1%" figure for agriculture's contribution to the UK's total CO2 emissions is a very significant underestimate. Using Defra's data, we believe that actually the contribution of agriculture to total UK CO2 emissions could be roughly of the order of 4%. We used figures for energy use as an indicator of the figures for CO2, as we were not able to find the figures for C02 emissions for indirect sources.

  9.  ADAS figures on the Defra website say the total energy consumption of the UK agricultural sector was 188.5 petajoules in 2002. Of this, only 44.9 petajoules (24%, just under a quarter) were attributed to "direct energy'. The rest, 76%, came from "indirect inputs".[70] From this, we conclude that the total figures for CO2 emissions would also be very roughly of the order of four times as much as stated were indirect sources included, ie c. 4%, instead of "less than 1%".

  10.  The indirect factors that are being excluded in UK climate change policy documents include the energy use from fertiliser which according to ADAS accounts for 101.2 petajoules, 54% of the total agricultural energy use; and also the energy from pesticide manufacture which is given as 9.4 petajoules, or 5% of the total. The contribution of fertilisers are so high as they are produced from fossil fuels. Together the use of agro-chemicals accounts for about 59% of total energy used in agriculture, but this is not being represented in the UK Government figures in its current Climate Change Programme.

Soil carbon emissions from changes in agricultural methods

  11.  It is well recognised that soils are major stores of carbon, containing approximately twice as much carbon as the atmosphere. So, even minor changes in soil carbon levels have a disproportionate effect on atmospheric levels of carbon and on progress towards emission reduction targets. According to a 1997 DETR document, soils in England, Wales and Scotland contain some 21.78 billion tonnes of carbon, of which 16.4 btC is in Scottish peat uplands[71], leaving 5.4btC in the soil of the remaining UK land where agriculture is the primary land use. Most of this is contained in grasslands. Arable soils in the UK contain 592 MtC (Smith et al).

  12.  There is currently considerable interest among policy makers in soils as potential carbon sinks. However, we are concerned that the past and on-going downward trend in agricultural soil carbon levels and the factors involved are not being adequately recognised. We believe that falling level of soil carbon due to changes in agricultural practices may be an important driver of climate change that is being neglected.

  13.  Worryingly, the carbon content of UK soils is falling. Defra's latest statistics from the National Soil Inventory show the organic content of soils in England and Wales has fallen from, in 1979-81, 22% of soil having an organic matter level of over 7%, to only 13% of soil having over 7% by 1995. The proportion with an organic matter level of less than 3.6% increased from 31% to 41%. In "Towards Sustainable Agriculture", MAFF stated that the organic content of our soil has decreased by 0.49% in the last fifteen years. Interestingly, between 1945 and 1986, the amount of carbon being released from the land tripled, with the most dramatic increase being between the mid '70s and mid '80s (Houghton et al). This coincides with the period of intensification of crop production.

  14.  Losses of soil carbon are mainly attributed to the ploughing up of grassland and other land use changes, and soil cultivation. However, emissions from changes in agricultural methods do not seem to have been recognised by the UK Government. The European Climate Change Program set up a working group on carbon stores related to agricultural soils. Their conclusions last year were that "there is evidence that under current agricultural practices, many European soils are losing organic carbon and thus constitute sources of atmospheric CO2 rather than sinks".[72] This urgently needs to be recognised and addressed by the UK Government.

  15.  One factor must be the abandonment of the use of organic matter (such as farmyard manure) as the basis of agriculture in favour of inorganic fertilisers as the main fertility source. This fundamental change in agriculture occurred mainly last century. A second major factor would be the increase in ploughing depth from the traditional 6 inches to 12 inches. This releases more soil carbon and requires more energy to be used in terms of machinery. Some experts have stated that this increase in ploughing depth has been mainly driven by the availability of more powerful agricultural machinery rather than by any agronomic need. A third factor would be the considerable increase in the density of grazing livestock in grassland areas. Studies in North Wales have shown that soil carbon density is significantly affected by the intensity of sheep grazing.[73]

  16.  We believe that the Government and industry's current focus on the role of soil cultivation (ploughing etc) is misleading. Agriculture has been using the plough for thousands of years, but atmospheric carbon levels have increased significantly only in recent years. There is little or no problem with ploughing practices in traditional and organic systems, where organic matter is regularly added and soil carbon levels are generally far higher than in intensively farmed systems. In our view, the problem is not necessarily ploughing per se, but (i) the general abandonment of the application of organic matter which previously would have replaced carbon lost from ploughing, and (ii) the unnecessary modern use of deep ploughs.

  17.  If it is true that these changes in agricultural practice have caused major historic and continuing releases of soil carbon, than this should change the implications for climate change policy in the field of agriculture considerably: the soil carbon bank should not be seen just as an interesting way in which climate change could be mitigated, but as an on-going climate change driver which must be addressed.

  18.  Firstly, there is an urgent need to quantify the past and current contribution of falling agricultural soil carbon levels to the UK's total CO2 emissions. Secondly, this needs to be included in the UK's data for the agricultural contribution of CO2 emissions, which currently apparently exclude all soil carbon emissions. Thirdly, there needs to be an attempt to properly quantify and recognise all the potential key factors involved here (not just focus on cultivation): the introduction of inorganic fertiliser, ploughing depth, and livestock stocking densities.

Soil breakdown of atmospheric methane

  19.  There seems to be no recognition of the agricultural impacts on soil on atmospheric methane levels. Methane has a global warming effect 21 times stronger than carbon dioxide (IPCC) and its atmospheric concentration has more than doubled over the past 100 years. It is produced by anaerobic decomposition of organic material and by the guts of ruminants, but is also being constantly destroyed by oxidation. Defra's figures say that in 1990 agriculture accounted for 28% of the UK's methane emissions, and due to changes in other sectors this proportion was projected to increase to 48% by 2010. However, the role of agriculture in the breakdown of methane is not being recognised.

  20.  Whilst most oxidation takes place in the atmosphere (85%), research by the IACR-Rothamsted has discovered that a significant amount is carried out by soil microbes, which use it as an energy source.[74] The researchers found that agriculture decreases natural soil oxidation rates by up to 80%. In particular, they found that the use of ammonium based N fertilisers causes a major reduction in soil oxidation rates. (In contrast, the repeated application of cattle manure had little effect). The decrease in oxidation rate was proportional to the amount of fertiliser applied. This contribution needs quantification and inclusion in the UK's figures for the impacts of agriculture on climate change.

Food and feed miles

  21.   One area which has received next to no mention in any official agricultural data source or climate change policy document has been the carbon dioxide emissions as a result of the transport of food, animal feed and agro-chemicals around the country. It is clear that the centralised food distribution which characterises the modern food industry contributes significant amounts to carbon dioxide emissions through the transport of food around the country, as well as the huge amounts of food exported and imported. It is often cited that approximately 25% of all road transport is accounted for by food transport. However, including other agricultural products, such as feed, swells this proportion even more. Government figures for the self-sufficiency of UK in food are very deceptive as modern intensive livestock farming is heavily dependent on the import of the large quantities of animal feed which is being produced on farms in other countries (such as soya from South America).

  22. In 2003, 34.4 billion tonnes km of foodstuffs and animal feed were transported around the country by road (the unit is a function of goods moved—the weight of the goods multiplied by the distance travelled). The figure for agricultural products and live animals was 13.2 billion tonnes km, and for the transport of fertilisers, 1.2 billion tonnes km. In total, these three categories accounted for 49% of all domestic freight moved in 2003.[75] There appears to be little attempt at addressing these figures in UK climate change or agricultural policy.

C.  Policies to address the climate change impacts of agriculture

More sustainable systems of agriculture—organic farming

  23.  Current UK climate change policies are very limited in the field of agriculture. We would like EFRA to promote a wider and much more ambitious approach in the next Climate Change Programme. In particular, we would like EFRA to acknowledge the benefits of organic farming and consider the potential role that this sector can play in the future. Organic farming offers the following automatic benefits for climate change policy:

  24.  (i)  Far greater energy efficiency in food production—A Defra desk-study found that organic farming is much more energy efficient than non-organic farming both on an area and yield basis.[76]

  For example, organic arable production is about 35% more energy efficient and organic dairy production about 74% more efficient per unit of output than non-organic production. In general, it is considered that organic farming use about 50% less energy than conventional agriculture for the production of the same quantity of food. This is because organic farming harnesses natural biological processes, which are driven by the sun's energy, rather than using artificial agro-chemicals which are produced from and distributed with the use of fossil fuels.

  25.  (ii)  Substantial potential for soil C sequestration—organic farming is based on the maintenance of the soil carbon bank. This is its fertility source as inorganic fertilisers are not used. The long-term comparative study of organic and non-organic farming by the Rodale Institute in the US, found that organic farming increased soil carbon levels by about 15-28% (from about 1.8% to about 2.3%), while conventional farming showed no significant increase in soil carbon over the same period. Importantly, this result was despite the fact that the conventional system returned a higher level of plant biomass to the soil—some supporters of conventional farming have tried to suggest that as conventional farming produces higher yields it would cause a greater build-up of soil carbon. This trial showed that the organic practices of using organic matter as the basis of the system instead of inorganic fertiliser and having a diverse crop rotation are key to building up soil organic matter. In the trial, the additional carbon retention of the organic system amounted to 2-4 tons per acre. If organic farming was adopted nationally, the researchers calculated that this would absorb 1 to 2% of the carbon dioxide released from the combustion of fossil fuels in the US.

  26.  (iii)  Reduced livestock grazing density—there are limits on livestock grazing density under organic standards. Densities are roughly 25% lower in organic farming than non-organic farming. This would reduce the soil carbon losses from the large grassland areas of the UK.

  27.  (iv)  Non-use of fertiliser—the non-use of inorganic fertilisers in organic farming means that nitrous oxide emissions are reduced and the ability of the soil to breakdown methane is increased.

  28.  (v)  Reduced feed and food miles—organic farming systems are more self-sufficient in terms of animal feed (more is produced on-farm) and also require less animal feed grains anyway, as there is a requirement for at least 60% of cattle feed to be forage (grass based). Local food marketing is also a much more significant feature of organic farming than non-organic, with many organic farmers marketing their produce through farm shops, vegetable box schemes and local farmers' markets.

  29.  (vi)  Greater resilience to climatic extremes—many organic farmers have noticed that their crops are more resilient to climatic extremes such as drought or heavy rainfall because of the better quality of their soils. This has been proven by the long-term comparative trial by the Rodale Institute in the US. It found that while the yields from conventional farming were substantially affected by drought, organic farming was not affected in the same way and substantially out-performed the non-organic system in these years. For example, in the four drought years for maize during the trial, the organic system yielded 16-37% more than the conventional system. This resilience of the organic system is because of the higher organic matter levels and better structure of the soils which mean it retains more moisture. The better soil structure means organically farmed land also absorbs water more quickly. For example, at the Rodale trial in 1995, the water infiltration rates were twice as high in the organic system than the non-organic. Resilience to drought and flooding should be an important consideration for agricultural policy as climate instability will increasingly effect agriculture.

  30.  It is important to note that organic farming also has other proven environmental benefits including: significant increases in farmland wildlife, and reductions in agrochemical pollution and waste.

Energy crops

  31.  We are concerned that the Government is intent on the widespread growing of energy crops. The Climate Change Programme says "The most effective way for the agriculture sector to contribute to reductions in greenhouse gas emissions is through the production of energy crops". We urge the Efra committee to take Defra up strongly on this. First of all, the most important way in which agriculture could reduce its GHG emissions is through a major reduction in the use of inorganic fertilisers, which are produced from fossil fuels. Secondly, there are some major concerns with energy crops.

  32.  Energy crops are not carbon neutral as claimed. Agriculture is currently a very energy intensive way of producing material, reliant on fertilisers and other agro-chemicals which use large quantities of fossil fuels in their production and transport. Fertilisers alone account for 54% of the energy used in farming. This means energy crops could actually have a negative impact on climate change. For example, a study by Cornell University estimated that it takes 1.7 litres of fossil fuel to produce 1 litre of ethanol (study by David Pimental, who chaired a US Department of Energy panel on energy, economics and environmental aspects of ethanol). Non-organic farming also causes declining soil carbon levels, pollution of water-courses and less farmland biodiversity. All this needs to be taken into account. The whole production chain therefore must be certain to produce significant net energy gain, before any plans for large-scale energy crop production in the UK can be considered. As a minimum, energy crops would have to be organically produced.

  33.  Secondly, there is only a finite amount of farmland and we believe sustainable food production must be the priority for agriculture. While healthy, sustainable food can only be produced from land, renewable energy can be produced from many non-crop sources: wind, solar, tidal and hydrogen. Energy crops would require a very large land area to make even a small contribution to the UK's energy use. But there is already an urgent need to de-intensify food production to make it sustainable and to grow more animal feed domestically to reduce our reliance on imported feed. This means that we cannot afford to dedicate large areas of farmland to energy crops. Large-scale energy crop production would mean more food and feed being imported, increasing fossil fuel use and our dependency on other countries for our basic resources.

Food transport

  34.  Localised food economies are key to reducing food miles and the related carbon dioxide emissions. Local food is currently recognised by the Government as a way of reconnecting consumers with the way food is produced. But more urgently, it should be seen as a priority for reducing the current very high food miles for climate change reasons.

D.  Government activities in the international arena

  35.  We suggest that the following should be the priorities for the Government in its forthcoming international roles.

Promoting accurate estimates for agriculture and the food sector

  36.  The UK Government should push for much more accurate estimates by climate change modellers working for the key institutions (eg. the IPCC and the Kyoto Protocol) for the contributions of the food and agriculture sectors to climate change. In particular, the major contribution from fertilisers should be recognised; and the past and on-going reductions in soil carbon levels from changes in agricultural practices need to be recognised. Also, the contributions of international trade in food and feed need to be included in national inventories—we understand this is currently omitted because a decision could not be made on how to allocate the contributions, whether to exporting or importing countries. This situation is unacceptable.

Promoting sustainable agricultural systems

  37.  Agricultural systems which have scientifically proven benefits for climate change policy and other aspects of the environment should be promoted internationally, such as organic farming. It is unacceptable that agrochemical and hence fossil-fuel dependent farming is being promoted abroad by the Government and international institutions.

European and international food trade

  38.  The UK Government needs to start a serious debate on the impacts and continued suitability of promoting international trade in food. The UK, European Union, and many other countries have been pursuing a policy of increasing food trade through trade negotiations and institutions such as the WTO. There is almost no official recognition, let alone action, of the substantial environment cost of this policy. This needs to change. In future, assessments of the benefits of trade agreements must consider the environmental costs of the increased transport of food that results from replacing local and regional food trade with international trade.

  39.  Secondly, the current trade policy barriers to developing more localised food distribution systems need to be seriously looked at. For example, because the EU is founded on the concept of promoting a single market, it is impossible for public authorities to overtly adopt local food purchasing policies on environmental grounds even though they are encouraged to consider the environmental impacts of their policies. This is clearly an nonsense. Also, "protectionism" is seen in only a wholly negative way by Governments. However, the environmental and food security (which will become more important as climate instability sets in) aspects of nationally-orientated agricultural policies are rarely considered. The UK should take a lead in opening the discussion on these issues.

19 October 2004

70   ADAS report for Defra using: Digest of UK Energy Statistics, Agriculture in the UK, Fertiliser Manufacture Association, Agricultural Engineers Association, Crop Protection Association. Back

71   Indicators of Sustainable Development in the UK, DETR, 1997. Back

72   Final Report on Working Group on Sinks Related to Agricultural Soils, Second ECCP Progress Report-Can we meet our Kyoto targets? European Climate Change Programme 2003. Back

73   "Wales' carbon-managing climate change", John Farrar, Chris Freeman and Davey Jones, University of Wales, Bongor, July 2003. Back

74   "Farming, Fertiliser and the Greenhouse Effect", T Willison, K Goulding, D Powlson and C Webster. Outlook on Agriculture, Vol 24, No 4.241-247 (1995). Back

75   Transport Statistics for Great Britain 2004. Department of Transport. Back

76   "Energy use in organic farming systems", Defra, 2000. Back

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