Appropriate focus by the development community on sustainable agriculture as providing adaptation, mitigation and increased productivity options, a ‘win-win-win’ scenario for agricultural development is possible in facing climate change.

Sustainable Organic Agriculture: Win-win Measures for Climate Change and Food Security

Introduction

Agriculture is a substantial contributor to climate change and is in turn seriously affected by it. Agriculture releases to the atmosphere a significant amount of carbon dioxide (CO₂), methane (CH₄) and nitrous oxide (N₂O). It accounted for an estimated emission of 5.1-6.1 GtCO₂-eq/yr in 2005, about 10-12% of global anthropogenic emissions of greenhouse gases (Smith et al., 2007). Of global anthropogenic emissions in 2005, agriculture accounted for about 60% of N₂O and about 50% of CH₄. If indirect contributions (e.g. land conversion to agriculture, fertilizer production and distribution and farm operations) are factored in, some scientists have estimated that the contribution of agriculture could be as high as 17-32% of global anthropogenic emissions (Bellarby et al., 2008). Emissions are increasing rapidly in agriculture and between 1990 and 2005 these increases are estimated to have been in the order of 17%. Emissions are expected to continue to increase due to increased demand for food as populations grow, and shifts occur in diets towards more meat consumption (Verchot, 2007).

Some of these emissions are caused by conventional practices in agriculture. Indeed, conventional and intensive agriculture characterized by mechanization and use of agro-chemicals (mineral fertilizers, herbicides, pesticides) and reliance on high external inputs (chemicals, irrigation, fossil fuels) have led to high environmental and social costs, including contributing to climate change, that may undermine future capacity to maintain required levels of food production.

At the same time, agriculture is also seriously impacted by climate change, the prognosis of which is sobering (IPCC, 2007b). On a global scale, the potential for food production is projected to increase with increases in local average temperature over a range of 1-3°C, but above this it is projected to decrease (IPCC, 2007b). Given that warming by the end of the 21st century (2090-2099) will be worse than expected and that the best estimates project a rise of 1.8-4°C, and a likely range of 1.1-6.4°C (IPCC, 2007a), the world is likely to see a decline in food production, if we continue business as usual.

For developing countries, including where some of the poorest people live and farm, the projections of climate change’s impacts are dire. Agricultural production, including access to food, in many African countries and regions, is projected to be severely compromised (IPCC, 2007b). The area suitable for agriculture, the length of growing seasons and yield potential, particularly along the margins of semi-arid and arid areas, are expected to decrease. This would further adversely affect food security and exacerbate malnutrition in Africa. In some countries, yields from rain-fed agriculture, which is important for the poorest farmers, could be reduced by up to 50% by 2020.

Given the dual relationship of agriculture and climate change, there is a need to mitigate emissions from agriculture on one hand, and to simultaneously undertake adaptation measures to ensure sustainability of food production and farmers’ livelihoods on the other hand. In this context of climate change, two questions thus arise: Can agriculture and farmers, particularly in developing countries, adapt to the adverse impacts of climate change, and are there ways to mitigate the impacts of agriculture on the climate?

A growing body of evidence is emerging to indicate that small-scale, sustainable agriculture may be the answer to both questions. This paper thus explores sustainable organic agriculture as a tool for mitigation of climate change and for adaptation, while at the same time being an effective tool for increasing food production and ensuring rural livelihoods.

Sustainable Organic Agriculture and Climate Change Mitigation

Agriculture is estimated to account for about 10-12% of the total global anthropogenic emissions of GHGs or between 5.1 and 6.1 GtCO2e per annum (Verchot, 2007). Of these, (1) methane (which has 20 times more global warming potential than carbon dioxide) accounts for 3.3 billion tonnes equivalent; (2) nitrous oxide (which has 300 times greater global warming potential than carbon dioxide) accounts for 2.8 billion tonnes annually; and (3) carbon dioxide emissions are 40 million tonnes (ITC 2007 in Khor, 2008).

Of the direct emissions, the main forms are:(1) nitrous oxide emissions from high nitrogen levels in the soils from synthetic fertilizers (2.128 billion tonnes), which are mainly associated with nitrogen fertilizers and manure applied to soils. Fertilizers are often applied in excess and not fully used by the crop plants, and some of the surplus is lost as nitrous oxide to the atmosphere; (2) enteric fermentation of cattle (1.792 billion tones); (3) biomass burning (672 million tones); (4) rice production (616 million tones),(5) manure handling (413 million tonnes) (Greenpeace 2008 in Khor, 2008).

Agriculture also contributes indirectly to emissions, through the energy intensive production of fertilizers, other farm operations and changes in land use. Long distance trade of agriculture products also contributes to emissions through transportation.

This indicates two things. First, most agricultural emissions come from chemical and energy intensive agriculture practices; secondly, there is a large potential for climate change mitigation in agriculture. Indeed, agriculture has the potential to change from being one of the largest greenhouse gas emitters to a much smaller emitter and even a net carbon sink, while offering options for mitigation by reducing emissions and by sequestering CO₂ from the atmosphere in the soil. The solutions call for a shift to more sustainable farming practices that build up carbon in the soil and use less chemical fertilizers and pesticides (Bellarby et al. 2008, ITC and FiBL, 2007, Ziesemer, 2007).

There are a variety of sustainable farming practices that can reduce agriculture’s contribution to climate change. These include crop rotations and improved farming system design, improved cropland management, improved nutrient and manure management, improved grazing-land and livestock management, maintaining fertile soils and restoration of degraded land, improved water and rice management, fertilizer management, land use change and agroforestry (Bellarby et al., 2008; Niggli et al., 2008, Smith et al., 2007).

The role of organic agriculture in reducing energy use, lowering greenhouse gas emissions and increasing carbon sequestration is described briefly below.

Reducing direct and indirect energy use in agriculture

The United Nations Food and Agriculture Organisation (FAO), reported in 2002 that, “Organic agriculture performs better than conventional agriculture on a per hectare scale, both with respect to direct energy consumption (fuel and oil) and indirect consumption (synthetic fertilizers and pesticides)”, with high efficiency of energy use (Scialabba and Hattam, 2002).

Organic farming is more energy efficient mainly because it does not use chemical fertilizers. Nitrogen (N) fertilizer is the single most energy intensive input, accounting for 53.7 percent of the total energy use. It takes 35.3 MJ of energy on average to produce each kg of N in fertilizers. UK farmers use about 1 million tonnes of N fertilizers each year (Biermann et al, 1999; Soil Association, 2007)

Since 1999, long-term comparative trials at the Rodale Institute in the United States have reported that energy use in the conventional system was 200 percent higher than in either of two organic systems – one with animal manure and green manure, the other with green manure only – with very little differences in yields (Petersen et al, 1999). Research in Finland has shown that while organic farming used more machine hours than conventional farming, total energy consumption was still lowest in organic systems Lotjonen, 2003); that was because in conventional systems, more than half of total energy consumed in rye production was spent on the manufacture of pesticides.

Organic agriculture was also found to be more energy efficient than conventional agriculture in apple production systems (Reganold et al, 200; PAN, 2001). Other studies in Denmark compared organic and conventional farming for milk and barley grain production (Dalgaard, 2003). The energy used per kilogram of milk produced was lower in the organic than in the conventional dairy farm, and it also took 35 percent less energy to grow a hectare of organic spring barley than conventional spring barley. However, organic yield was lower, so energy used per kg barley was only marginally less for the organic than for the conventional.

The Soil Association (2007) found that organic farming in the UK is overall about 26 percent more efficient in energy use per tonne of produce than conventional farming, excluding tomatoes grown in heated greenhouses. The savings differ for different crops and sectors, being the greatest in the milk and beef, which use respectively 28 and 41 percent less energy than their conventional counterparts.

Lower greenhouse gas emissions

The FAO estimated that organic agriculture is likely to emit less nitrous oxide (N₂O) (Scialabba and Hattam, 2002). This is due to lower N inputs, less N from organic manure from lower livestock densities; higher C/N ratios of applied organic manure giving less readily available mineral N in the soil as a source of denitrification; and efficient uptake of mobile N in soils by using cover crops.

Greenhouse gas emissions were calculated to be 48-66 percent lower per hectare in organic farming systems in Europe (Stolze et al, 1999), and were attributed to no input of chemical N fertilizers, less use of high energy consuming feedstuffs, low input of P, K mineral fertilizers, and elimination of pesticides, as characteristic of organic agriculture. Niggli et al. (2008) estimate that a conversion to organic agriculture would diminish N₂O emissions by two-thirds due to no external mineral nitrogen input and more efficient nitrogen use. Organic agriculture is also self-sufficient in nitrogen due to recycling of manures from livestock and crop residues via composting, as well as planting of leguminous crops (ITC and FiBL, 2007).

Many experiments have found reduced leaching of nitrates from organic soils into ground and surface waters, which are a major source of nitrous oxide. A study reported in 2006 also found reduced emissions of nitrous oxide from soils after fertilizer application in the fall, and more active denitrifying in organic soils, which turns nitrates into benign N₂ instead of nitrous oxide and other nitrogen oxides (Kramer et al., 2006)

It is also possible that moving away from a grain-fed to a predominantly grass-fed organic diet may reduce the level of methane generated, although this has yet to be empirically tested. Mike Abberton, a scientist at the Institute of Grassland and Environmental Research in Aberystwyth, has pointed to rye grass bred to have high sugar levels, white clover and birdsfoot trefoil as alternative diets for livestock that could reduce the quantity of methane produced (Organic Inform, 2007).

Increased carbon sequestration

Soils are an important sink for atmospheric CO₂, but this sink has been increasingly depleted by conventional agricultural land use, and especially by turning tropical forests into agricultural land.

Niggli et al. (2008) estimate that a conversion to organic agriculture would considerably enhance the sequestration of CO₂ through the use of sustainable techniques that build up soil organic matter. Organic systems have been found to sequester more CO₂ than conventional farms, while techniques that reduce soil erosion convert carbon losses into gains (Bellarby et al., 2008, ITC and FiBL, 2007, Niggli et al., 2008).

The evidence for increased carbon sequestration in organic soils seems clear. Organic matter is restored through the addition of manures, compost, mulches and cover crops.
The Sustainable Agriculture Farming Systems (SAFS) Project at University of California Davis in the United States (Clark et al, 1999 and 1998) found that organic carbon content of the soil increased in both organic and low-input systems compared with conventional systems, with larger pools of stored nutrients. Similarly, a study of 20 commercial farms in California found that organic fields had 28 percent more organic carbon (Drinkwater, et al, 1995). This was also true in the Rodale Institute trials, where soil carbon levels had increased in the two organic systems after 15 years, but not in the conventional system (Peterson et al, 1999). After 22 years, the organic farming systems averaged 30 percent higher in organic matter in the soil than the conventional systems (Ho, 2005).

In the longest running agricultural trials on record of more than 160 years, the Broadbalk experiment at Rothamsted Experimental Station, manure-fertilized farming systems were compared with chemical-fertilized farming systems (Rothamsted Research, 2006). The manure fertilized systems of oat and forage maize consistently out-yielded all the chemically fertilized systems. Soil organic carbon showed an impressive increase from a baseline of just over 0.1 percent N (a marker for organic carbon) at the start of the experiment in 1843 to more than double at 0.28 percent in 2000; whereas those in the unfertilized or chemical-fertilized plots had hardly changed in the same period. There was also more than double the microbial biomass in the manure-fertilized soil compared with the chemical-fertilized soils.

Sustainable agriculture helps to counteract climate change by restoring soil organic matter content as well as reducing soil erosion and improving soil physical structure. Organic soils also have better water-holding capacity, which explains why organic production is much more resistant to climate extremes such as droughts and floods (Ho, 2005), and water conservation and management through agriculture will be an increasingly important part of mitigating climate change.

Sustainable Organic Agriculture and Climate Change Adaptation

Adaptation to climate change can be both autonomous and planned. Autonomous adaptation is the ongoing implementation of existing knowledge and technology in response to the changes in climate experienced; planned adaptation in the increase in adaptive capacity by mobilizing institutions and policies to establish or strengthen conditions that are favourable to effective adaptation and investment in new technologies and infrastructure (Easterling, 2007).

Autonomous adaptation is highly relevant for smallholder farmers in developing countries (IFAD, 2008). Crucially, many of these autonomous adaptation options are met by sustainable agriculture practices. By increasing resilience within the agroecosystem, sustainable agriculture increases its ability to continue functioning when faced with unexpected events such as climate change (Borron, 2006).

Practices that enhance biodiversity allow farms to mimic natural ecological processes, enabling them to better respond to change and reduce risk. Resiliency to climate disasters is closely linked to farm biodiversity, so farmers who increase interspecific diversity via sustainable agriculture suffer less damage compared to conventional farmers planting monocultures (Altieri and Koohafkan, 2008, Borron, 2006, Niggli et al., 2008). Moreover, the use of intraspecific diversity (different cultivars of the same crop) is insurance against future environmental change.

Sustainable farming practices that preserve soil fertility and maintain or increase organic mater can reduce the negative effects of drought while increasing productivity (ITC and FiBL, 2007, Niggli et al., 2008). Water holding capacity of soil is enhanced by sustainable agriculture practices that build organic matter, helping farmers withstand drought (Altieri and Koohafkan, 2008, Borron, 2006). In addition, water-harvesting practices allow farmers to rely on stored water during droughts. Other practices such as crop residue retention, mulching and agroforestry conserve soil moisture and protect crops against microclimate extremes. Organic matter also enhances water capture in soils, significantly reducing the risk of floods (ITC and FiBL, 2007, Niggli et al., 2008).

Indigenous and traditional knowledge are a key source of information on adaptive capacity, centered on the selective, experimental and resilient capabilities of farmers (Altieri and Koohafkan, 2008, Borron, 2006, IAASTD, 2008, ITC and FiBL, 2007, Niggli et al., 2008). Many farmers cope with climate change, by minimizing crop failure through increased use of drought-tolerant local varieties, water-harvesting, extensive planting, mixed cropping, agroforesty, opportunistic weeding and wild plant gathering. Traditional knowledge, coupled with the right investments in plant breeding, could yield new varieties with climate adaptation potential.

New knowledge related to sustainable agriculture, when practiced through farmers’ participation are also effective adaptation measures. A well known example is the System of Rice Intensification (SRI) approach to rice farming, which can be an adaptation strategy in drier areas. In Indonesia, the applicatIon of SRI has been hailed as an effort to revive rice production self-sufficiency in the country through the use of local resources and less water. A 46% reduction in water use and yields of up to 10-12 tons per ha have been reported in Indonesia. This has eased the problems of rice farming in the dry seasons. Some 10 thousand farmers have used the organic SRI method in 13 provinces in Indonesia, covering about 6 thousand ha. (http://beras-organik.blog.com/2523857). In some cases, the SRI method is adopted through sharing of knowledge with farmers, showing that new techniques that are adaptable by the farmers and that do not create dependence on outside inputs can be easily adopted by farmers.

Food Security and Rural Livelihoods

Sustainable organic agriculture is a win-win solution for tackling climate change and to enhance food security as well as promote rural livelihoods. Evidence shows that in general, yields from sustainable agriculture can be broadly comparable to conventional yields in developed countries. In developing countries, sustainable agriculture practices can greatly increase productivity, particularly if the existing system is low-input, which is largely the case for poor subsistence farmers.

The following provides a brief description of the potential of organic agriculture to enhance food security and rural livelihood, based on global modelling and reviews of projects.

A recent study examined a global dataset of 293 examples and estimated the average yield ratio of different food categories for the developed and developing world (Badgley et al., 2007). On average, in developed countries, organic systems produce 92% of the yield produced by conventional agriculture. In developing countries, however, organic systems produce 80% more than conventional farms. Organic methods were also found to hypothetically produce enough food on a global per capita basis to sustain the current human population, and potentially an even larger population, without putting more farmland into production.

In a review of 286 projects in 57 countries, farmers increased agricultural productivity by an average of 79%, by adopting “resource-conserving” sustainable agriculture (Pretty, 2006, Pretty et al., 2006). A variety of sustainable technologies and practices were used, including integrated pest management, integrated nutrient management, conservation tillage, agroforestry, water harvesting in dryland areas, and livestock and aquaculture integration.

The work built on earlier research, which found that for 89 projects for which there was reliable yield data, farmers had, by adopting sustainable agriculture practices, achieved substantial increases in per hectare food production – the yield increases were 50-100% for rain-fed crops, though considerably greater in a number of cases, and 5-10% for irrigated crops (Pretty and Hine, 2001). Disaggregated data show that average food production per household rose by 1.7 tonnes per year (up 73%) for 4.42 million small farmers growing cereals and roots. There was an increase in food production of 17 tonnes per year (up 150%) for 146,000 farmers cultivating roots. Meanwhile, total production rose by 150 tonnes per household (up by 46%) for the larger farms in Latin America.

The database was reanalyzed to produce a summary of the impacts of organic and near-organic projects on agricultural productivity in Africa (Hine and Pretty, 2008). The average crop yield increase was even higher for these projects than the global average: 116% increase for all African projects and 128% increase for the projects in East Africa. Moreover, all case studies that focused on food production where data have been reported showed increases in per hectare productivity of food crops, challenging the myth that organic agriculture cannot increase agricultural productivity.

There are many other examples of increased yields following the application of sustainable approaches, with concrete benefits for smallholder and subsistence farmers and their households (Hine and Pretty, 2008, Parrott and Marsden, 2002, Pretty and Hine, 2001, Scialabba and Hattam, 2002). Benefits include a shift from cereal deficit to producing annual surpluses; reduction in chemical use with ensuing health and environmental benefits; soil fertility improvement and conservation of traditional seeds.

Policy Challenges

The information provided above indicates the potential of sustainable organic agriculture to deal with the multiple challenges of climate change, ensuring productivity to provide for food security, particularly for the poorest and most vulnerable, and ensuring environmental sustainability. However, some challenges have to be overcome in order to tap the potential of organic agriculture.

The first challenge is the need for extensive and intensive documentation on the benefits of organic agriculture, especially in developing countries. There is a deficit of data and information from developing countries on climate change mitigation and adaptation in agriculture, despite the fact that many farmers practice organic agriculture and have played a part, to a certain extent, in managing climate change. This is mainly because many farmers do not keep records, while universities and governments do not consider organic agriculture as a priority (as opposed to highly mechanized, technology intensive agriculture) – in other words simply a lack of interest and support for organic agriculture. The other factor is the fact that farmers in different regions, within a country, practice various methods of organic, agro-ecological farming systems, in different climate zones and ecosystems, and therefore one standard research methodology cannot be used for all regions and practices. Also, while documentation on productivity and environmental sustainability of organic agriculture is increasing, the data on climate mitigation and adaptation potential is still in deficit.

Second, there has been prolonged neglect of the agriculture sector, even conventional agriculture, at the national level, and in terms of international cooperation. This is evident from the fact that the World Development Report 2008 called for greater investment in agriculture in developing countries (World Bank, 2008). While it now appears that there is a resurgence of agriculture on the development agenda it is clear that a new agricultural paradigm is needed, one that can deal with the multiple challenges, including climate change. The overarching priority is therefore to put the idea of sustainability at the centre of agricultural policies rather than at the edge (Pretty, 2006).

Third, organic agriculture is not yet broadly recognized as a potential development strategy, and even less as climate change mitigation and adaptation strategy (Müller 2009). Thus there is a policy deficit of support to organic agriculture in many countries, particularly developing countries. Policy support is needed to provide incentives to encourage farmers to shift to organic agriculture, and to intensify research and development of approaches that can help farmers.

Fourth, policies are often sectoral in nature, while organic agriculture is supposed to address multiple challenges. Thus, an integrative, holistic policy approach is key to tapping the potential of organic agriculture to address climate change and food crises. Many autonomous adaptation measures found within sustainable agriculture are effective against climate variability, while also contributing to poverty reduction, and need to be urgently supported by the development community and integrated into development projects. Mitigation measures related to organic agriculture likewise have potential to contribute to sustainable rural development.

This is related to the fifth challenge, which is the need to give voice to farmers. Supporting and facilitating farmers’ knowledge on mitigation and adaptation measures need to be critically enhanced, as they have been by-passed in the past (IAASTD, 2008). This requires creating space for diverse voices and perspectives and a multiplicity of options, as well as enabling farmers to do more through capacity building programmes.

Sixth, is the issue of incentives. For example, there is significant room for promoting pro-poor mitigation measures through increasing the profitability of sustainable agriculture practices (Rosegrant et al., 2008). Incentives for smallholder farmers from developing countries to adopt mitigation practices need to be enhanced, including payment for environmental services (IFAD, 2008; Rosegrant et al., 2008). At the same time, because some options may not have favourable outcomes for smallholder farmers, these need to be critically assessed, and mechanisms to buffer farmers against negative impacts are essential.

However, in the face of accelerating climate change and other crises, it is necessary that incentives are integrated into development projects, policies and strategies. In this case, the financial requirements of organic agriculture as an adaptation and mitigation strategy are low. The appropriate institutional structure is more of a priority need. While the market has a role to play, the main incentives should be built into the public financing of integrated development strategies.

Seventh, there is also deficit in the development of knowledge and technologies that are community-based, environmentally-friendly and socially viable. The long-term viability of organic agriculture needs knowledge and techniques on seed breeding, post-harvest processing, and cultivation methods that are easily adaptable at the local level, and are not hindered by proprietary rights.

These challenges can be overcome, through investing more resources, research and training into, providing appropriate policy support to, and implementing national, regional and international action plans on sustainable agriculture. Priorities for development agencies and governments towards sustainable agriculture include investing in research and extension for agricultural sustainability, as these are essential for adapting and transferring technologies; technical assistance and capacity-building for relevant ministries; land reform to encourage investment in asset building; agricultural development programmes that build rural social capital, particularly for women to access credit; supporting small-scale agribusinesses in rural areas; supporting urban agriculture; working with farmers’ and rural people’s organizations; and establishing appropriate economic and regulatory incentives to encourage transitions towards sustainability (Pretty 2006).

Conclusion

The challenges facing agriculture are immense. However, with appropriate focus by the development community on sustainable agriculture as providing adaptation, mitigation and increased productivity options, a ‘win-win-win’ scenario for agricultural development is possible.

Given the many advantages of organic farming and sustainable agriculture, in terms of climate change as well as social equity and farmers’ livelihoods, there should be a much more significant share of research, personnel, investment, financing and overall support from governments and international agencies that should be channelled towards sustainable agriculture. Promotion of sustainable agriculture can lead to a superior model of agriculture from the environmental and climate change perspective, as high-chemical and water-intensive agriculture is phased out, while more natural farming methods are phased in, with research and training programmes also promoting better production performances in sustainable agriculture.

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