TECHNIKFOLGENABSCHÄTZUNG Theorie und Praxis
Herausgeber: Institut für Technikfolgenabschätzung und Systemanalyse (ITAS)
|Nr. 2, 20. Jahrgang - Juli 2011, S. 45-52 [pdf]|
A major strategic decision for meeting global food needs is whether this should be attempted by continuing along the current technological trajectory, or whether divergent paths should be considered. Trends such as shrinking arable land per capita, growing water constraints for agriculture, higher energy and production input costs, and the need to preserve environmental quality give impetus for an agro-ecological approach to sustainable production intensification in which biological processes are utilized to enhance factor and total productivity. The “System of Rice Intensification” (SRI) developed in Madagascar has been demonstrating substantial productivity gains and other benefits through making changes in crop, soil, nutrient, and water management, rather than from introducing new varieties or increasing external production inputs. The scientific controversy over SRI should subside as increasing evidence supporting its claims gets accepted into the published literature.
The challenge of meeting global food demand in the decades ahead raises a question of strategy: To what extent can this goal be met by doing “more of the same” – by simply continuing along the present technological path and finding better solutions in this direction? Posing this question raises a corollary query: Should we be charting some new avenues to increase food production?
These questions do not presume that there will or can be a wholesale shift to alternative methods of production; this will not in any case be practical or feasible in the short to middle run. However, there are some facts and trends, reviewed below, that suggest we should be considering alternative strategies that diverge from our present technological trajectory.
The conditions under which the food needed to meet population demands in this 21st century will be produced will surely be different from those that shaped agricultural production in the preceding century. Alterations in these conditions indicate that significant changes will need to be made in the methods employed for food production. The economic and environmental reasons for utilizing what qualify as “agro-ecological” approaches are becoming clearer, reflecting objective realities rather than just ethical or other preferences.
In particular, experience accumulated over the past decade with a production system known as the System of Rice Intensification (SRI), increasingly reinforced by scientific investigations, is pointing to lower-cost opportunities for increasing world food availability, especially for those persons who are most in need. SRI management, applicable also beyond rice, achieves this by making more productive use of available resources. This strategy differs from most of those currently proposed for raising food production, and it makes SRI quite unprecedented, offering some new directions for agricultural technology and policy to explore and elaborate.
The first section below reviews what SRI management can contribute to meeting the challenge of world food production. This leads into a consideration of the factors and trends that are likely to make this century’s agricultural systems diverge from the practices, policies, and structures during the previous century. The article then considers briefly the origins of SRI; how it has spread and what it involves in concrete terms; then the scientific controversy and evidence surrounding it; and finally some future implications.
Which agricultural technologies prove to be most productive and sustainable over time depends upon institutional relationships and upon the relative availability and productivity of the principal factors of production (Hayami, Ruttan 1985). The combination of still-growing population, at least through to 2050, and continuing declines in arable land, both in quantity and in quality through various causes of soil-system degradation, will by 2050 reduce the food production area available per capita to about one-third of what it was in 1950.
Accordingly, the comparative advantage of large-scale, mechanized, extensive production can be expected to decline over time. While labor shortages in the agricultural sectors of poorer countries can create incentives for what are called “modern” production methods, the economic logic for intensification of production will become stronger over time in terms of relative factors availability and productivity.
This logic will gain strength when energy costs are considered. While petroleum prices cannot be predicted with any certainty even years ahead, let alone for decades, there is no reason to expect energy prices for agriculture in the 21st century to match those in the 20th century. The profitability of farm operations that depend on mechanization and on fertilizer and agrochemical inputs that derive from petroleum materials will be undermined by present and future increases in energy prices. While alternative energy sources can mitigate the financial pressure, there are limits on how far they can substitute for current fossil fuel-based agricultural inputs.
Perhaps trumping all of these influences will be the effects of climate change, for which global warming is only one element, and possibly not the most important. Farmers can, within limits, adapt to gradual increases in ambient temperature, by modifying cropping patterns as well as practices. What they cannot readily adapt to are increases in what are euphemistically grouped as “extreme events” – droughts, storms, heat waves, cold snaps. The effects of these will probably be exacerbated by intensified pest and disease problems.
There are also legitimate concerns that continuing our present heavy reliance on applying large amounts of inorganic nitrogen fertilizer will have other adverse impacts on the environment. These and other considerations make “doing more of the same” a less attractive and possibly infeasible option. Future agricultural production is unlikely to be as extensive as was evolved during the 20th century. This recasts the question to: if agriculture becomes more intensified, with what kind of intensification? The current brand of “intensification” with its heavy reliance on agrochemical inputs is acknowledged by rice scientists as not really sustainable (Cassman, Harwood 1995; Reichardt et al. 1998). There is need, but also opportunity, for a more suitable strategy of sustainable intensification (Royal Society 2009).
The magnitude of the challenge of meeting world food needs is so great that certainly there will be no single solution or single strategy for achieving this objective. Neither SRI nor the broader phenomenon of agro-ecology can suffice for this purpose by itself. However, evidence from SRI experience over the past decade suggests that making certain changes in crop management can greatly enhance the productivity of available land, labor, water, nutrient, and capital. These changes make it possible to increase food production with less rather than more cost. Achieving greater output with reduced inputs is a controversial proposition, to be sure. For the past century, higher output has been achieved with greater external inputs, but the impacts of agricultural expansion have had adverse consequences for the world’s natural resource base.
The impacts of SRI management have been reviewed in a number of publications
It can be difficult to believe all of these impacts from SRI management practices because they sound “too good to be true”. But these effects are well documented as the practices described below evoke more productive phenotypes from a wide range of rice genotypes, from traditional “unimproved” cultivars as well as from modern varieties and hybrids. It is noteworthy that the principles and practices of SRI are now being adapted to a variety of other field crops such as wheat, sugarcane, millet, maize, and even some legumes and vegetables.
The results so far do not justify a campaign to convert all crop management to SRI or related practices. But they do suggest that food production in the future can be more satisfactory than is anticipated with current purchased input-dependent technologies (Uphoff 2007).
The set of irrigated rice production methods known as SRI (originally Le Système de Riziculture Intensive) was developed in Madagascar by Henri de Laulanié, S.J., a French priest trained in agriculture who spent half a lifetime working there with poor, smallholding farmers. His empirical insights and experimentation led to an assemblage of practices in the mid-1980s that make the resources used in rice cultivation more productive (Laulanié 1993; Uphoff 2006; Uphoff, Kassam 2009).
While SRI has considerably evolved over the past 25 years, even being extrapolated to use with other crops beyond rice, in its original form SRI mostly involved half a dozen changes in conventional rice cultivation methods. All of these represent generalizable principles that are well justified by agronomic science. But in its most concrete form, SRI can be presented in terms of modifications of age-old, common practices for anaerobic or flooded rice cultivation around the world.
These methods, when used as recommended with suitable local adjustments (spacing, timing, water management), have enabled farmers in different parts of Madagascar, who had been getting average yields of ~2 tons/ha, to produce two to four times more paddy without use of purchased inputs. What is intensified with SRI is not external inputs, but knowledge, skill, and management. During their learning phase, farmers need to make greater labor inputs. But once the techniques were mastered, farmers could reduce these inputs as well as their seed, water, and costs of production (Moser, Barrett 2003; Barrett et al. 2004).
The merits of SRI’s alternative methods have gained acceptance only slowly in Madagascar, in part because they visibly contradict (and appear to disrespect) “the ways of the ancestors” which are the foundation of Malagasy culture and religious beliefs. Where there was not enough water control to apply small but reliable amounts of irrigation water, this also impeded the uptake of SRI.
In 1994, the Cornell International Institute for Food, Agriculture and Development (CIIFAD) began working with “Association Tefy Saina”, the NGO that Frère Laulanié and Malagasy colleagues established in 1990 to promote SRI. The NGO name did not mean “produce more rice” but “improve the mind/mentality,” indicative of SRI’s dual objectives, to introduce socio-economic improvements along with resource-conserving agricultural development and food security.
In 1999 and 2000, through CIIFAD efforts, the validity of SRI methods was demonstrated outside Madagascar for the first time, through trials managed by rice scientists at Nanjing Agricultural University in China, and at the Sukamandi rice research institute of the Indonesian Ministry of Agriculture. By 2011, the number of countries where SRI methods have been validated has reached 42. SRI has been shown to work in tropical, subtropical, and temperate environments and across dry, subhumid, and humid moisture climates.
To reach this extent, a great variety of institutions have given support to SRI evaluation and/or expansion at the country level:
These varied organizations working separately but in effect together, with coordination and communication through CIIFAD, have made SRI an unprecedented civil society innovation (Lines, Uphoff 2006). It is different from the more typical agricultural innovations that emanate from the scientific establishment and are transmitted through official extension agencies to farmers needing new opportunities. This could have prompted some of the resistance to SRI.
During the period 1998–2002, a series of theses on SRI was written for the Department of Agronomy at the University of Antananarivo using standard scientific methods which confirmed Tefy Saina’s reports on SRI. It was supported by two of the most eminent rice scientists in the world, Prof. Yuan Long-ping in China and Dr. M.S. Swaminathan in India, who showed SRI productivity through their own evaluations. But nevertheless, there were several contradictory articles published in 2004 which dismissed SRI methods as having no general merit (Sheehy et al. 2004), or minimized their importance by asserting that SRI is only “a niche innovation” (Dobermann 2004), or argued that even evaluating SRI would be a waste of resources (Sinclair, Cassman 2004). A subsequent article concluded that SRI is inferior to “best management practices” developed by scientists (McDonald et al. 2006). Despite rebuttals of the data and analysis presented in these critical articles (Stoop, Kassam 2005; Uphoff et al. 2008), these critiques and other objections succeeded in making SRI “controversial”, so that during the past decade, foundations and donor agencies have generally refrained from giving support for the evaluation of SRI methods in a more systematic way than NGOs and SRI practitioners could undertake without funding and research expertise. Thus far, only Jim Carrey’s “Better U Foundation” has provided support for trans-national work on SRI, also funding SRI dissemination in Madagascar, Mali, and Haiti.
Even without financial backing, however, a number of scientific studies have begun appearing in the literature, e.g., Lin et al. (2009), Mishra and Salokhe (2008), Thakur et al. (2010), Uphoff et al. (2009), and Zhao et al. (2009). Evaluations from countries as varied as the Gambia (Ceesay et al. 2007), Indonesia (Sato, Uphoff 2007), and Myanmar (Kabir, Uphoff 2007) have provided information on the empirical foundations of SRI performance.
In March 2011, the journal Paddy and Water Environment published a special issue on SRI (Vol. 9, No. 1). This contained half a dozen scientific articles plus nine country reports from Afghanistan via Iraq to Mali to Panama that brought together a strong evidential base supporting the previous claims and reports on SRI productivity. Quite possibly, attention will now focus on a better understanding of the agro-ecological mechanisms that produce SRI results – particularly the larger and longer-lived root systems and the more abundant and diverse soil biota that support higher crop productivity. There should no longer be much doubt about the potential payoff from getting a better understanding of the mechanisms, limitations, and optimization of SRI methods. Explaining and exploiting this potential and addressing sustainability questions is important and remains to be done systematically.
The productive possibilities that SRI experience and understanding are opening up will not by themselves meet the challenge of feeding the world. But there is enough evidence now to support expanding our investigation and dissemination of the principles and practices that constitute SRI, especially as extrapolated to other crops beyond rice. SRI represents a paradigm shift for the agricultural sector: from an external input-dependent approach, revolving around genetic improvements or modifications, to more of an ecological perspective and strategy.
In a way, SRI amounts to a “re-biologization” of agriculture, which has during the past hundred years been made a more industrial, engineered undertaking. Within both frameworks, the critical relationships are between inputs and outputs. But in an industrial operation, there are always proportional relations between the two sets of factors. From an industrial perspective, plants are like carbon-based machines, to be designed and re-designed to meet our purposes.
Understood in ecological terms, plants are organisms with their own capacities, strategies, repertoires, etc., that are activated in response to environmental conditions. Plants do not exist and survive separately from their surroundings, but rather they are thoroughly interpenetrated by – and for the most part benefited by – microorganisms, much as humans and other animal depend on their respective microbiomes. Instead of regarding soil mostly in terms of its inert mineral elements, this alternative perspective appreciates the potentials, limitations, and dynamics of soil systems as a living component of agro-ecosystems (Uphoff et al. 2006). Whereas most soil science focuses on soil chemistry and soil physics, with only a minority of research focused on soil biology, the latter should be the crux of soil analysis if realistic knowledge is sought. Much contemporary soil science is based on studies of soil samples that have had the life in them destroyed by fumigation or sterilization, so that our generalizations and conclusions are based on cadaverous soil, not on functioning soil systems.
When the life in the soil is husbanded, parallel to a crop husbandry that regards plants as organisms rather than as machines, we see some spectacular productivity results possible, in rice, wheat, sugarcane, and many other crops. We do not know how far the experiences with SRI and related methods can be taken; but there is reason to think that with good evaluation and further evolution of the methods and insights, some major advances can be made beyond what has been achieved so far.
Who would have thought that soil rhizobia migrating from the root zone up through the roots and stems into rice plant leaves would, by themselves and under controlled conditions, be able to increase plants’ levels of chlorophyll, rates of photosynthesis, and ultimate grain yield? (Chi et al. 2005) Or that “infecting” rice seeds with a fungus (Fusarium culmorum) could induce greater root growth and earlier emergence of root hairs that help seedlings grow more vigorously? (Rodriguez et al. 2009) There is still much to be discovered and evaluated. But this will not happen without moving beyond genocentric, input-focused agricultural strategies.
We must be careful not to let the successes to date create unrealizable expectations; but neither should the divergence of SRI practices and results from present thinking and achievements justify resistance to innovation, based on a priori reasoning or vested interests that benefit from the status quo. The challenges of the next several decades are too immense and ominous for “business as usual” to offer any sustainable comfort.
 The former chief executive of the UK’s Natural Environmental Research Council, John Lawton, has characterized the rising use of N fertilizer as “the third major threat to our planet, after biodiversity loss and climate change” (Nature, 24 February 2005), referring to the impacts of reactive nitrogen on water quality and aquatic ecosystems.
 See Uphoff and Kassam 2009; Africare/Oxfam America/WWF-ICRISAT Project 2010; Kassam, Uphoff and Stoop 2011.
Africare; Oxfam America; WWF-ICRISAT Project, 2010: More Rice for People, More Water for the Planet. WWF-ICRISAT Project, Hyderabad, India; http://www.sri-india.net/documents/More_Water_For_The_Planet.pdf (download 22.6.11)
Barrett, C.B.; Moser, C.M.; Barison, J. et al., 2004: Better technologies, better plots or better farmers? Identifying changes in productivity and risk among Malagasy rice farmers. In: American Journal of Agricultural Economics 86 (2004), pp. 869–888
Cassman, K.G.; Harwood, R.R., 1995: The nature of agricultural systems: Food security and environmental balance. In: Food Policy 20 (1995), pp. 439–454
Ceesay, M.; Reid, W.S.; Fernandes, E.C.M. et al., 2007: Effects of repeated soil wetting and drying on lowland rice yield with System of Rice Intensification (SRI) methods. In: International Journal of Agricultural Sustainability 4 (2007), pp. 5–14
Chi, F.; Shen, S.H.; Cheng, H.P. et al., 2005: Ascending migration of endophytic rhizobia, from roots to leaves, inside rice plants and assessment of benefits to rice growth physiology. In: Applied and Environmental Microbiology 71 (2005), pp. 7271–7278
Dobermann, A., 2004: A critical assessment of the system of rice intensification (SRI). In: Agricultural Systems 79 (2004), pp. 261–281
Hayami, Y.; Ruttan, V.W., 1985: Agricultural Development: An International Perspective. Baltimore, MD
Kabir, H.; Uphoff, N., 2007: Results of disseminating the System of Rice Intensification with Farmer Field School methods in Northern Myanmar. In: Experimental Agriculture 43 (2007), pp. 463–476
Kassam, A.H.; Uphoff, N.; Stoop, W.A., 2011: Review of SRI modifications in rice crop and water management and research issues for making further improvements in agricultural and water productivity. In: Paddy and Water Environment 9 (2011), p. 1; DOI: 10.1007/s10333-011-0259-1
Laulanié, H. de, 1993: Le système de riziculture intensive malgache. In: Tropicultura 11 (1993), pp. 110–114, Brussels
Lin, X.Q.; Zhu, D.F.; Chen, H.X. et al., 2009: Effect of plant density and nitrogen fertilizer rates on grain yield and nitrogen uptake of hybrid rice (Oryza sativa L.). In: Journal of Agricultural Biotechnology and Sustainable Development 1 (2009), pp. 44–53
Lines, G.A.; Uphoff, N., 2006: A remarkable civil society contribution to food and nutrition security in Madagascar and beyond. In: Kracht, U.; Schulz, M. (eds.): Food and Nutrition Security in the Process of Globalization and Urbanization. Münster, pp. 426–438
McDonald, A.J.; Hobbs, P.R.; Riha, S.J., 2006: Does the System of Rice Intensification outperform conventional best management? A synopsis of the empirical record. In: Field Crops Research 96 (2006), pp. 31–36
Mishra, A.; Salokhe, V.M., 2008: Seedling characteristics and early growth of transplanted rice under different water regimes. In: Experimental Agriculture 44 (2008), pp. 1–19
Moser, C.M.; Barrett, C.B., 2003: The disappointing adoption dynamics of a yield-increasing, low external-input technology: The case of SRI in Madagascar. In: Agricultural Systems 76 (2003), pp. 1085–1100
Reichardt, W.; Dobermann, A.; George, T., 1998: Intensification of rice production systems: Opportunities and limits. In: Dowling, N.G.; Greenfield, S.M.; Fischer, K.S. (eds.): Sustainability of rice in the global food system. International Rice Research Institute (IRRI), Los Baños, Philippines, pp. 127–144
Rodriguez, R.J.; Freeman, D.C.; McArthur, E.D. et al., 2009: Symbiotic regulation of plant growth, development and reproduction. In: Communicative and Integrative Biology 2 (2009), pp. 1–3
Royal Society, 2009: Reaping the Benefits: Science and the Sustainable Intensification of Global Agriculture. Report of Commission chaired by Sir D. Baulcombe, The Royal Society, London
Sato, S.; Uphoff, N., 2007: A review of on-farm evaluations of system of rice intensification (SRI) methods in eastern Indonesia. In: CAB Reviews 2/54 (2007), pp. 1–12
Sheehy, J.E.; Peng, S.; Dobermann, A. et al., 2004: Fantastic yields with the system of rice intensification: Fact or fallacy? In: Field Crops Research 88 (2004), pp. 1–8
Sinclair T.R.; Cassman, K.G., 2004: Agronomic UFOs? In: Field Crops Research 88 (2004), pp. 9–10
Stoop, W.A.; Kassam, A.H., 2005: The SRI controversy: A response. In: Field Crops Research 91 (2005), pp. 357–360
Thakur, A.K.; Uphoff, N.; Antony, E., 2010: An assessment of physiological effects of system of rice intensification (SRI) practices compared to recommended rice cultivated practices in India. In: Experimental Agriculture 46 (2010), pp. 77–98
Uphoff, N., 2006: The development of the System of Rice Intensification. In: Gonsalves, J. (ed.): Participatory Research and Development for Sustainable Agriculture and Rural Development, Vol. III. International Development Research Centre, Ottawa, pp. 119–125
Uphoff, N., 2007: Agricultural Futures: What lies beyond “Modern Agriculture”? In: 2nd Hugh Bunting Memorial Lecture. Tropical Agriculture Association Newsletter, September 13–19; http://www.sw-websolutions.co.uk/taa/assets/pubs/2ndBMLSept2007.pdf (download 22.6.11)
Uphoff, N.; Ball, A.; Fernandes, E.C.M. et al. (eds.), 2006: Biological Approaches to Sustainable Soil Systems. Boca Raton, FL
Uphoff, N.; Stoop, W.A.; Kassam, A.H., 2008: A critical assessment of a desk study comparing crop production systems: The example of the “system of rice intensification” versus “best management practice”. In: Field Crops Research 108 (2008), pp. 109–114
Uphoff, N.; Kassam, A.H., 2009: Case Study: The System of Rice Intensification (SRI). In: Agriculture for Developing Countries, Annex 3. European Parliament, Brussels; http://www.europarl.europa.eu/stoa/publications/studies/stoa2008-02_annex3_en.pdf (download 22.6.11)
Uphoff, N.; Anas, I.; Rupela, O.P. et al., 2009: Learning about positive plant-microbial interactions from the System of Rice Intensification (SRI). In: Aspects of Applied Biology 98 (2009), pp. 29–54
Zhao, L.M.; Wu, L.H.; Li, Y.S. et al., 2009: Influence of the System of Rice Intensification on rice yield and nitrogen and water use efficiency with different N application rates. In: Experimental Agriculture 45 (2009), pp. 275–286
Prof. Dr. Norman Uphoff
Cornell International Institute for Food, Agriculture and Development (CIIFAD)
Warren Hall, Ithaca, NY 14853 USA
Phone: +1 - 6 07 - 2 55 - 19 02
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