Prof. Martin Wolfe (Elm Farm Research Centre) gave an excellent paper at the GA2020 Conference at the John Innes Centre on 19 April 2001. Here is the complete text, which he has given me permission to circulate.
Cheers,
Jeremy
Jeremy Bartlett This email address is being protected from spambots. You need JavaScript enabled to view it.
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ABSTRACT
Recognising and realising the potential of organic agriculture
M S Wolfe
Elm Farm Research Centre, Hamstead Marshall, Newbury, Berks RG20 0HR, UK
Abstract
Organic agriculture operates within closed cycles so as to limit the environmental impact of the food and farming system. However, current production levels are lower than in non-organic agriculture although the difference is offset partly by higher external costs in non-organic agriculture. A major reason for the difference is the impact of greater investment in non-organic R and D. However, current evidence indicates that application of sustainable agriculture research can increase production significantly while reducing environmental impacts throughout the food chain. Further spread of sustainable production needs a major shift in funding for research and development and for its implementation.
PAPER
Recognising and realising the potential of organic agriculture
M S Wolfe
Elm Farm Research Centre, Hamstead Marshall, Newbury, Berks RG20 0HR, UK
The evolution of modern, non-organic agriculture
The shock of the Second World War and the Cold War exposed the fragility of contemporary food systems. Agricultural policies were introduced to encourage production including massive investment in production-oriented research and development. Within limits, this was outstandingly successful.
As food became abundant, prices fell and the secure food policy changed into a cheap food policy, reinforced by globalisation. Agriculture and food processing became industrialised. By the end of the twentieth Century, the proportion of each pound spent on food in the UK that was returned to the farmer fell to less than 10% while the proportion of the population involved directly in production fell below 2%, with negative consequences for rural communities and services.
Other problems emerged including soil erosion, pollution of soil, air and water, loss of lowland birds and a range of animal and human health problems associated with intensive animal production. Estimates of costs caused by such problems came to £208 per hectare (Pretty et al, 2000), almost equal to the subsidy provided by the European taxpayer for farming to continue in this direction.
Dealing with the problems of non-organic agriculture
Considerable efforts are made to deal with the environmental problems of non-organic agriculture from the inside. For example, pesticide and fertiliser use is now more regulated and targeted than previously and there is significant interest in agri-environment stewardship schemes.
However, to deal with the structural causes of the problems requires a fundamentally different approach, for example, through organic agriculture.
This raises two major questions:
a) can organic agriculture be sustainable, by avoiding negative impacts on natural and human capital?
b) can organic agriculture provide needed levels of production?
What is organic agriculture?
Some of the main objectives of organic agriculture are:
A. Natural Capital
1. Improve the structure and fertility of soil
2. Work within closed cycle systems using local resources
3. Give livestock conditions that conform to their needs
4. Maintain and encourage wildlife and their habitats
5. Minimise the use of non-renewable resources and avoid pollution
B. Human Capital
1. Produce food of high nutritional quality and sufficient quantity
2. Enable producers to earn a living and to develop their potentials
3. Create systems that are aesthetically pleasing
4. Use decentralised systems for local processing, distribution and marketing
To achieve these objectives requires a holistic view of the food chain and of the many interactions involved. Organic agriculture has standards that formalise the application of these objectives and that are under constant review.
Progress with organic agriculture
For organic agriculture in the UK, the costs of negative impacts may be only one-third of those in non-organic, while the positive benefits are greater (Pretty, 2001). And, today, average grain yields of organic cereals (Lampkin and Measures, 2001) are about 4 t/ha with potato gross yields at about 40 t/ha, about double the average yields of the late 1940s (Moore, 1949). However, over the same period, average non-organic yields have doubled again, to more than 8 t/ha for wheat and 50 t/ha or more for non-irrigated potatoes.
Why should there be such a difference in output? A major reason lies in the relative scales of research investment. The high yields from non-organic agriculture are based on an R and D budget over the last 50 years that runs into billions of pounds from both public and private sectors. This is a subsidy to 'northern' agriculture which, for the public sector, has been paid for by the taxpayer and not the farmer. There have been some spin-offs for the organic farmer, but the R and D budget that has gone directly into organic agriculture has been pitifully small and over a much shorter period.
Organic Research and Development in the North
Long-term comparisons in tomato, apple and maize production, show no differences between organic and non-organic. In the maize analysis, comparing conventional and organic systems, Drinkwater et al. (1998) showed that maize yields did not differ, but also that the organic systems sequestered significantly larger amounts of carbon and nitrogen and reduced nitrogen losses so that sustainability was improved without yield loss.
But how do we explain yields that are much less under organic than non-organic conditions? For example, in 2000, six modern wheat varieties yielded, on average, 10 t/ha across national trials (NIAB, 2000) under standard non-organic conditions. When these varieties were grown organically, the yield fell to less than 4 t/ha (unpubl.). Oat and triticale varieties under the non-organic conditions yielded, respectively, 8.2 and 6.5 t/ha. However, the same varieties grown organically yielded, respectively, 7.1 and 6.7 t/ha.
Why should there be such a discrepancy between wheat on the one hand, and oats and triticale on the other? The main reason is that wheats bred for non-organic production, are short-strawed with an open canopy, so that they compete less well with weeds than the taller, denser oats and triticales. There is a similar contrast in disease resistance. Modern wheat varieties, adapted to utilising synthetic fertiliser inputs, may also have lost some ability to interact with soil for their required nutrition, relative to older varieties (Foulkes et al. 1998). There is an urgent need, therefore, to breed organic wheat.
In the meantime, weed control can be improved by physical and agronomic means. For disease control, we can use variety mixtures. For example, a mixture of three wheat varieties in the same organic trials provided simultaneous restriction of three diseases, resulting in 16% yield increase relative to the mean of the three varieties grown as pure stands.
Variety mixtures provide disease protection and improved yield stability (Finckh et al, 2000) for an increasing area of crops world-wide including about half a million hectares of wheat mixtures in the west of the US (Garrett and Mundt, 1999). A recent initiative with rice in China (Zhu et al. 2000), demonstrated that as the area of mixed crops increases, so does their effectiveness.
Research and Development in the South
Analysis of 208 projects in 52 countries covered some 9 million farms on 29 million hectares that have adopted sustainable (largely organic) agriculture practices (Pretty and Hine, 2001). A common feature was reduced soil erosion and improved water management through the use of cover crops, inter-cropping, reduced tillage and development of mulch-based systems. Many projects revealed important interactions. For example, by introducing fish culture into paddy rice in China, local diet was improved, but, more importantly, mosquito larvae were consumed by the fish, leading to a massive reduction in malaria. Outstanding in many countries were methods for developing farmer participation in research and development.
The projects fulfilled many of the criteria of sustainability and did so with production increases often between 50% and four-fold. If such successes in developing local production and consumption while improving rural social structures could be extended, then such projects would have a significant impact on world hunger and poverty.
Future research needs for organic agriculture
To meet the twin aims of increasing production while reducing environmental impact requires R and D initiatives of many kinds at many levels. The suggestions below attempt to give an indication of some important areas and of the need for awareness of the effects that any single action might have on the whole food chain.
a) Methodologies
Reductionist or linear approaches to deal with specific questions at lower systems levels will remain important. However, there is a great need for ecological and social sciences to deal with higher systems levels. Non-linear approaches can help in the understanding of emergent properties, those unexpected developments that arise in complex dynamic systems.
There is a need for participative approaches including producers, processors and consumers. These may be concerned with different parts of the local food chain at the level of the farm, the landscape and the region.
b) Production systems
Systems need to have a wider range of functions. One example is agroforestry in which trees, crops and animals are integrated within a management unit. Such systems can also provide a basis for renewable energy generation. Complex systems encourage diversity at the biological, market and cultural levels while increasing opportunities for rural employment.
Crop rotations are understood at only an empirical level. There is potential for refining existing systems and for developing alternatives, including for example, inter-cropping and companion cropping.
b) Soil
We must improve our understanding of function and dynamics within soil microbial populations. We need to know how the functions may be modified to improve soil fertility and structure and also the disease and pest resistance of soil. Soil nutrient budgeting in current research is necessarily superficial; it needs to evolve in the light of more fundamental understanding.
In maintaining closed cycles, there is still much to learn about the development and use of manures and composts from on-farm and off-farm by-products. These vary in quality but need to be more predictable in performance and better targeted for specific needs.
d) Crops
There is an urgent need for breeding for populations or varieties adapted for organic production. Characters for selection need to be defined and prioritised. DNA technologies could be helpful in defining parents and evaluating progress. The methodology should include assessment of candidates for variety and species mixtures and for inter-cropping. There is a need for improvements in seed and transplant production methods.
Improved management of perennial grass weeds needs integration of aspects of crop breeding, rotation and cultivation management, physical methods and selection of inter-crop species that are competitive with, or allelopathic against, the weeds. We still do not fully understand the positive roles of weeds in ground cover, and in encouraging beneficial organisms, plant nutrition and disease interactions.
e) Livestock
Again, there is a need for directed breeding programmes for livestock appropriate to organic farming - DNA technologies may be similarly useful for defining parents and evaluating breeding progress.
Further progress is needed in integrating livestock nutrition into overall farm systems, in terms of closing cycles and improving energy use efficiency. Animal health and welfare is crucial, using low stocking rates integrated into systems that are environmentally acceptable and economically viable. Animal behaviour studies should contribute more to systems that encourage development of healthy animals.
The semiochemicals that generate signals among organisms are of interest for both plant and animal welfare. For example, a system of trap plants that attract pests and inter-crop plants that repel them, can control stem borer in maize and sorghum (Pickett, Herren). In animal welfare, pheromones can attract sheep blowfly to traps early in the year when the pest population is small. Control at this stage can reduce the need for sheep-dipping (Pestech, 2001).
f) Other aspects
Many other links in the food chain need research including food quality and processing, development of appropriate local marketing strategies and improving our understanding of farming systems that encourage wildlife at the farm and landscape levels.
Policy and Funding
Policy and funding changes that are needed for sustainable agriculture are happening, both within and outside government. Many European and other governments now spend more on sustainability projects than previously.
However, to plan for a major shift towards greater sustainability in the food chain needs consideration of larger-scale changes in funding to provide the engine for change. We need to reflect on the extraordinary speed of response both in research and in farming that resulted from the major investment in agricultural R and D from the 1950's.
Conclusions
Organic agriculture limits its impact on the environment by operating as far as possible within closed cycles, along the whole of the food chain. As these systems evolved, production increased, but not to the same level as in industrialised agriculture, although negative side-effects have been less. A major contributor to the difference in production is the greater investment in research and development over a longer period that has gone into non-organic agriculture.
Current research indicates that organic production levels can be similar to those from non-organic and that it should be possible further to improve production while simultaneously reducing environmental impact. Many of the required R and D activities should provide outcomes of interest for all agricultural systems, particularly in relation to environmental impact.
To deliver these objectives will require policy changes in terms of funding for agriculture, with a particular shift in funding for R and D for organic and sustainable agriculture and for its delivery to the farmer.
References
Drinkwater L E, Wagoner, P and Sarrantonio, M (1998). Legume-based cropping systems have reduced carbon and nitrogen losses. Nature 396: 262-264. Finckh, M R, Gacek, E S, Goyeau, H, Lannou, C, Merz, U, Mundt, C C, Munk, L, Nadziak, J, Newton, A C, de Vallavieille-Pope, C and Wolfe, M S (2000). Cereal variety and species mixtures in practice, with emphasis on disease resistance. Agronomie 20: 813-837.
Foulkes M J, Sylvester-Bradley R and Scott R K (1998). Evidence for differences between winter wheat cultivars in acquisition of soil mineral nitrogen and uptake and utilization of applied fertilizer nitrogen. Journal of Agricultural Science, 130, 29-44.
Garrett K A and Mundt C C (1999). Epidemiology in mixed host populations. Phytopathology 89: 984-990.
Lampkin N and Measures M (2001). 2001 Organic Farm Management Handbook. Aberystwyth: University of Wales, Aberystwyth and Elm Farm Research Centre.
Moore H I (1949). Crops and Cropping. London: George Allen & Unwin Ltd. (4th edition).
NIAB (2000). UK Recommended Lists of Cereals 2000. Cambridge: NIAB Pestech (2001). www.pestech.demon.co.uk.
Herren H and Pickett J (2001). Kenya: Vutu-sukumu (push-pull) pest management in smallholder systems. DFID-University of Essex "Reducing Poverty through Sustainable Agriculture" Conference, St James's Palace, London, January 2001.
Pretty J (2001). The real costs of modern farming. Resurgence 205: 7-9.
Pretty J and Hine R E (2001). Rural poverty, food security and sustainable agriculture: findings from research investigating 207 sustainable agriculture projects. DFID-University of Essex "Reducing Poverty through Sustainable Agriculture" Conference, St James's Palace, London, January 2001.
Pretty J, Brett C, Gee D, Hine, R E, Mason C F, Morison J I L, Raven H, Rayment M D and van der Bijl G (2000). An assessment of the total external costs of UK agriculture. Agricultural Systems 65: 113-136.
Zhu Y, Chen H, Fan J, Wang Y, Li Y, Chen J, Fan J, Yang S, Hu L, Leung H, Mew T W, Teng P S, Wang Z and Mundt CC (2000). Genetic diversity and disease control in rice. Nature 406: 718-722.