Global Food Security 3 (2014) 125–132

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Global Food Security

journal homepage: www.elsevier.com/locate/gfs

Food wedges: Framing the global food demand and supply challenge towards 2050

Brian A. Keating n, Mario Herrero, Peter S. Carberry, John Gardner, Martin B. Cole

CSIRO Sustainable Agriculture Flagship, Ecosciences Precinct, Block B Level 3, Dutton Park, Qld 4102, Australia article info abstract

Article history: A projection of global food demand to 2050, with assumptions on population growth, dietary shifts and Received 3 March 2014 biofuel expansion, provides an estimate of the amount of additional food needed over the next 40 years Received in revised form to satisfy human needs. This additional food demand, expressed in kilocalories, represents a “mega- 22 August 2014 wedge” akin to the carbon stabilisation wedges of Pacala and Socolow (2004). This food demand Accepted 25 August 2014 challenge consists of three component “food wedges” classed according to their target pathways: i.e. pathways that target reducing food demand; pathways that target increasing food production; and Keywords: pathways that target sustaining the productive capacity of food systems. In this paper we examine these Global food security wedges in terms of prospective pathways through which food supply and demand can stay in balance Food demand over the next 40 years. Within these wedge classes, we nominate 14 pathways that are likely to make up Food wedges the food security ‘solution space’. These prospective pathways are tested through a survey of 86 food Solutions fi Pathways security researchers who provided their views on the likely signi cance of each pathway to satisfy Framework projected global food demand to 2050. The targeting of pathways that contribute to filling the production gap was ranked as the most important strategy by surveyed experts; they nominated that 46% of the required additional food demand is likely to be achieved through pathways that increase food production. Pathways that contribute to sustaining the productive capacity are nominated to account for 34% of the challenge and 20% might be met by better food demand management. However, not one of the 14 pathways was overwhelmingly ranked higher than other pathways. This paper contributes a simple and comprehensive framing of the “solution space” to the future food demand challenge and a portfolio of investment pathways proposed to meet this challenge. Crown Copyright & 2014 Published by Elsevier B.V. All rights reserved.

1. Introduction seen by many as a “sunset industry” in the developed world and our science and business institutions were consumed by the The performance of the global food system over the last 50 “sunrise industries” of the “Silicon Revolution”. However, this years has been nothing short of remarkable. Total food supply has perception was overturned dramatically by the food price shocks increased almost threefold in the face of a twofold increase in of 2007/08 and 2009/10, a 3- to 6-fold increase in prices of population and very significant shifts in diet related to economic selected commodities, and significant human suffering and poli- development. The proportion of undernourished people in devel- tical unrest (Mitchell, 2008). Since this time there has been an oping regions decreased from 23.2% in 1990–92 to 14.9% in 2010– explosion of interest in the global food security challenge. 12 and the Millennium Development Goal (MDG) of halving the There is no shortage of reports and analyses produced over the percentage of people suffering from hunger by 2015 appears to be last five years that seek to diagnose the global food security within reach (UN, 2012, 2013). Despite this impressive progress, challenge ahead (CA, 2007; IAASTD, 2009, Beddington et al., one in eight people remain chronically undernourished in 2014. 2012). A search of the Web of Science (Thomson Reuters) database At the start of the 21st Century, a sense of complacency had reveals 1075 papers published between 2008 and 2013 with the crept into the collective global consciousness. Expanding food term ‘food security” in the title – a 4-fold increase over a decade supply to meet a rapidly growing human population was generally earlier. Such reports tend to be dominated by exploration of the seen as 20th Century problem that had been solved by the Green drivers of food demand increase and prospects for a food supply Revolution (Hazell and Ramasamy, 1991). In 2000, agriculture was response (IAASTD; 2009). Other reports target individual demand or supply interventions (Bouwman et al., 2005, Fraiture et al., 2007; Nelson et al., 2009; Valin et al., 2013). The “Safe Operating n ” Corresponding author. Space exploration of food security (Beddington et al., 2012), based E-mail address: [email protected] (B.A. Keating). on the principles of Rockstrom et al. (2009), elegantly frames the http://dx.doi.org/10.1016/j.gfs.2014.08.004 2211-9124/Crown Copyright & 2014 Published by Elsevier B.V. All rights reserved. 126 B.A. Keating et al. / Global Food Security 3 (2014) 125–132 problem and describes the interconnected forces of population and non-food commodity trajectories down to a single figure. The growth, consumption growth, environmental change and food total volume of agricultural products (in tonnes) is sometimes security. used, but this approach is deficient in that it combines very Despite the plethora of studies focused on the “problem heterogeneous commodities into a single undifferentiated unit. definition space”, there is no simple and comprehensive framing The calorific value of food products is also used as a common unit of the “solution space”. Assessing the food security solution space to develop aggregated demand trajectories from very different presents significant challenges due to the lack of available high commodities (Valin et al., 2014). This approach has some value as resolution data to study comprehensively and consistently all it can be simply related to per capita consumption statistics, but aspects globally. In addition, issues of additivity and trade-offs of care is needed in considering non-food demands such as for the different solutions, adequate costs and adoption rates, assump- biofuels and/or for animal feed, as the amounts of different tions about technological change and the breath of application of commodities could be under or over-estimated depending on the practices make such analyses difficult (Von Lampe et al., 2014). degree to which non-food uses of food products are included. Also, Traditionally, the global change community has used integrated nutritional security (Traore et al., 2012) is acknowledged as assessment tools, partial equilibrium and computable general extending well beyond meeting the food energy requirements in equilibrium models, together with crop and livestock simulation diet and these issues are not captured in a calorific measure. models to assess the impacts of a narrow set of options (yield FAO's most recent revision of agricultural demand to 2050 has increases, climate change impacts, technological change, improved used international dollar prices to weight a diverse set of com- markets) under different socio-economic conditions (Nelson et al., modities under a single index of production (Alexandratos and 2014; Valin et al., 2014; Von Lampe et al., 2014). While these tools Bruinsma, 2012). Price-weighted production metrics will capture and approaches continue to develop, even the most comprehen- changes in the agricultural production mix from lower value sive cannot fully quantify all possible pathways. Nevertheless, new commodities to higher value commodities commonly associated modelling efforts are constantly improving our understanding and with development. For example, China's food consumption per modelling of the global food system (CIMSANS, 2014; Von Lampe capita measured by FAO's price-based volume index doubled from et al., 2014). 1989–91 to 2005–07 but increased by only 16% when expressed in In this paper we seek to create a framing for the “solution terms of calories. This reflects rapid diet shifts to higher value space” for matching global food demand and supply over coming horticultural and livestock based commodities. decades. This framing parallels the carbon stabilisation wedges There are upsides and downsides of all aggregated metrics. We postulated by Pacala and Socolow (2004). We simply address the have chosen to use an energy-equivalent basis (kcal yr-1), questions of what are the options by which food supply can be acknowledging that it captures only one dimension of human diet matched to future food demand and how do these options and that it does not fully address shifts in diet preferences with compare in terms of relative significance in the global food budget income growth. and ease of implementation? Our focus is primarily on the “food Keating and Carberry (2010) constructed a simple set of food availability” element of food security. We recognise that the demand scenarios based on population forecasts (UN 2012) and physical supply of food (availability) is only one dimension of per capita consumption of food energy, either with existing food security, with other key determinants being food utilisation consumption patterns for developed and developing countries and nutritional value and food accessibility (World Food maintained, or with the developed world staying static and the Summit, 1996). developing world increasing per capita consumption to match the developed world by 2050. That analysis suggests an increase in food demand over the 2010 to 2050 period as low as 35% (with 2. Estimating future global food demand 8.1 billion people) to more likely 50–80% increases with 9.2 billion people; the variation relates to consumption per capita shifts and Establishing a food demand trajectory is an essential first step biofuel diversions. in framing the “solution space” of food supply. The basic drivers of Valin et al. (2014) recently compared the food demand routines change in food demand are well recognised and primarily relate to in ten global food system and economic models. In the reference population growth, demographics and shifts in the level and scenario (AGMIP-SSP2), food demand increases by 59–98% composition of diets with income changes and urbanisation. between 2005 and 2050, slightly higher than the most recent Societal changes in attitudes and values, as well as environmental FAO projection of 54% from 2005–2007. The range of results is change, affecting food preferences and/or supply might also large, in particular for animal calories (between 61% and 144%), impact on demand trajectories but these appear to be minor caused by differences in demand systems specifications and influences to date in the face of the key demographic and diet income and price elasticities. Four estimates of future food drivers. demand are compared in Table 1. The analysis developed here is The diversion of food products to biofuels also adds to the independent of the absolute estimate of demand, but it is demands on global agricultural land, water and production activ- conceptually important for the demand estimate to include all ities and it is logical to include a biofuel demand element in future sources that are relevant to the supply pathways under considera- agricultural production targets (Searchinger et al., 2008; Havlík tion. For this reason, we have used the upper bound of the Keating et al., 2011). Finally, the issue of food waste from producer to and Carberry (2010) analysis, given it includes waste and biofuel consumer is a important term in the global food balance (Godfray considerations. et al., 2010). Some food waste is implicitly embedded in food consumption data (e.g. at the processing, distribution and house- hold end of food supply chains), while other sources of food waste 3. A “mega wedge” of additional food demand (e.g., at the producer and farm-gate end of the supply chain) are excluded. We were inspired in our work on the food security challenge by A figure of 70% expected increase in food demand by 2050 is the work of Pacala and Socolow (2004) who were confronted with often quoted and attributed to FAO (Bruinsma, 2003). a similar problem in exploring the global greenhouse gas abate- Alexandratos and Bruinsma (2012) explain the source of this ment challenge. They identified two projections for atmospheric figure and the pitfalls inherent in reducing a complex set of food greenhouse gas emissions, namely an upper “business as usual” B.A. Keating et al. / Global Food Security 3 (2014) 125–132 127

Table 1 Some estimates of food demand in 2030 and 2050 relative to 2010.

Reference Food demand % Change 2010 Notes (kcal yrÀ1 Â 1015) to 2050

2010 2030 2050

Alexandratos and 7.0a 9.0 10.3 45 Updated FAO forecasts – excludes on-farm waste and biofuels Bruinsma. (2012) Valin et al. (2014) 7.0 8.9 10.5 50 AGMIP SSP2 scenario based on GLOBIOM model. Excludes biofuels and on farm waste Pardey et al. (2014) 7.1 9.2 10.9 53 iAP Model based on ecometric estimates of crop-based food demand augmented by biofuel demand estimates Keating and Carberry 7.3– 9.8– 12.0– 64–71 Range depends on assumptions around biofuels on-farm waste. Assumes developing and developed (2010) 8.9 12.3 15.3 per capita consumption converge by 2050

a 2010 estimate interpolated from 2005/07 data and 2030 estimate. projection and a lower projection which represented the abate- ment profile the world needs to achieve if it is to limit global warming in 2050 to under 2 1C. These two projections formed a triangle the area of which approximated the 175 GtC that needs to be kept out of the global atmosphere to avoid dangerous climate change in 2050. Pacala and Socolow (2004) proceeded to sub- divide this triangle into “wedges” each representing 1 GtC/yr in 2055 and then to explore the prospects for current or prospective technologies, practices or polices to deliver on the necessary wedges. By selecting the upper bound of food demand projection suggested by Keating and Carberry (2010), we can approximate the additional food demand to 2050 as a triangular mega-wedge of cumulative global food demand for the period 2010 to 2050 (equivalent to 127 Â 1015 kcal). (Fig. 1a). This calculation of the “mega-wedge” has two implicit simplifying assumptions, namely that global food demand and supply were in broad balance in 2010 and that the 2010 to 2050 demand trajectory can be approximated by a linear relationship. With regard to the first assumption, it is reasonable for our purposes here given broadly similar numbers of under and over nourished in the world and relatively stable food stocks – implying a net balance at the global level. The second assumption on demand linearity is needed to work with simple triangular wedges and this is appropriate to the close to linear demand estimates shown in Table 1. This simple “wedges” frame- work will not be viable in situations where there is significant non-linearity in the upper bound of the demand trajectory. Any actions that reduced global food demand can reduce the size of the overall mega-wedge (Fig. 1b). Four pathways are proposed as “demand reduction” actions (Table 2). In an analogous manner, the lower bound of the mega-wedge is not fixed and any drivers that reduce current or future food supply will increase the size of the mega-wedge. It is critical for actions that contribute to “sustaining the current productive capacity” are included in any prioritisation of global food security efforts and four such path- ways are proposed (Table 2). A further six solution pathways represent the opportunities to fill the “production gap” caused by population growth and diet shifts and they include many of the traditional pathways by which food supply has kept pace with Fig. 1. Additional food demand from 2010 till 2050 represented as (a) A single food demand in the past (Table 2). “mega-wedge” of additional demand and (b) three conceptual “wedges” of equal size reflecting different strategies in the solution space. 3.1. Pathways that reduce food production demand

3.1.1. Reducing waste along the food value chain Waste occurs throughout the food value chain, on farm, in developed and developing world. For example, most food waste storage, in processing, in the marketplace and in households. in the developing world occurs before it reaches the consumer due Estimates vary, but figures in the 20–40% range are reported to poor harvesting practices, lack of adequate storage systems, (Godfray et al., 2010; FAO, 2011). A host of complex technical, lack of cold chains, pests and diseases. In contrast, most waste in economic and social drivers are implicated. The location of the the developed world is due to sell-by dates in supermarkets, waste and the significance of the drivers differ between the restaurants and households. Any reductions in waste within the 128 B.A. Keating et al. / Global Food Security 3 (2014) 125–132

Table 2 The “mega-wedge” broken down into three distinct strategies with nominations for the key pathways under each strategy. The per cent contribution is as ranked by stakeholders in the field of agriculture and food security research.

Strategy Pathway Overall contribution (%) Standard deviation

A. Pathways that target reducing the food production demand curve 20.4 12.6 1. Reducing food waste from farm to consumer 6.1 4.3 2. Reducing over-consumption in human diets 4.1 3.8 3. Rebalancing the livestock component of future diet 5.0 4.4 4. Developing “smart” biofuel policies and/or technologies 4.1 3.0

B. Pathways that target filling the production gap 46.0 17.7 5. Expanding the land resources used for agricultural production 3.4 3.1 6. Expanding the water resources used for agricultural irrigation 5.1 4.2 7. Expanding aqua-culture (on land or in oceans) 5.9 3.9 8. Closing yield gaps in existing crop and/or livestock production systems 14.8 9.2 9. Developing new farming systems that intensify land/water use 9.1 6.2 10. Crop and/or livestock improvement to lift the genetic potential 7.3 4.5

C. Pathways that involve avoiding losses in current or future production potential 33.6 15.9 11. Maintaining pest and disease resistance and biosecurity 8.2 6.9 12. Avoiding soil and water degradation 10.4 6.5 13. Minimising climate change through mitigation that maintains food security 5.4 4.0 14. Adaptation to climate change that can't be avoided. 9.2 5.2

Note: percentage ratings for individual pathways (1–14) do not add to the individual wedge percentages because they exclude the 1.9% of total votes placed by survey respondents against additional pathways. production and consumption systems would reduce the global 3.1.4. Developing smart biofuel policies and technologies food demand trajectory. In 2011, 15% global maize production (largely in the USA), 10% vegetable oil production (largely in Europe) and 14% sugar pro- duction (largely in Brazil) were diverted to biofuel manufacture 3.1.2. Reducing over-consumption in Human diets (data sourced from FAOSTAT and USDA). The prospects are that the Some of the current and projected food demand arises from demand for biofuels will continue to grow, depending on cost over-consumption of food with growing health consequences in competitiveness with conventional and unconventional fossil both the developed and some segments of society in the devel- fuels, technological advances such as cellulose to biofuel and oping world. Global estimates suggest 1.4 billion adults, 20 and policy settings. Advances in biofuel technologies and/or policies older, are overweight, compared to 1.0 billion undernourished that mean biofuels will be less competitive with food crops (or the (WHO, 2008). Of these overweight adults, over 200 million men land and water used to produce food crops) represent a pathway and nearly 300 million women are obese. Reducing over- towards food security in 2050. consumption and achieving more balanced and nutritious diets could help reduce future food demand trajectories and deliver associated health benefits such as reduction in cardiovascular 3.2. Pathways that increase food production diseases, diabetes and metabolic syndromes (McMichael et al., 2007). 3.2.1. Expanding the net land footprint The land footprint of global agriculture is estimated at 4894 million ha in 2010 (FAOSTAT, 2013). Over the period 1961 to 2000, 3.1.3. Balancing the livestock component of future diets the land footprint grew by only 11%, while agricultural output Livestock products make up 17% and 30% of the global kilo- grew by 153% (FAOSTAT, 2013). In much of the world, food demand calorie and protein consumption respectively. Livestock product was met by increasing food output per unit land and only consumption is growing in response to rising living standards, modestly by increasing land devoted to agriculture. Sub-Saharan especially in the fast growing economies in Asia, Latin America Africa was an exception with land expansion the major source of and parts of Africa (IAASTD, 2009). While there are nutritional increased food production (36 million ha). Some of the future food benefits associated with a livestock-derived component in diets, demand to 2050 could be met by expanding agriculture onto land dietary shifts towards livestock products are driving over half of not previously cleared or cultivated. Estimates of additional arable the future food production demand. Producing calorie energy and land vary, but Alexandratos and Bruinsma (2012) report up to protein from livestock takes an estimated 2.5 to 100 times more 1.4 billion ha of either good or prime land that could be brought resources than from grain (Herrero et al., 2013). Currently, one under cultivation if needed, albeit with some loss of pastures and third of the world's cereal grain supply is used for livestock feed, significant infrastructure investment. Lambin et al., 2013 have resulting in lower energy efficiencies (De Fraiture et al., 2007; FAO, used a fine scale bottom up approach and suggest much lower 2006). Projections suggest that livestock feeding will account for areas of land suited to expansion of arable agriculture when all close to 50% of cereal grain use by 2050 (IAASTD, 2009). An constraints are considered. Clearing or cultivation of forestland or increase in the direct cereal consumption by humans would boost grassland comes at the price of a significant greenhouse gas load the global food system's energy efficiency, although the reality is with climate change implications as well as biodiversity impacts. that cereal consumption per capita has remained constant in many parts of the world (FAOSTAT, 2013). Garnett et al. (2013a, 2013b) note that behavioural shifts in existing diets in developed coun- 3.2.2. Expanding the irrigation water supply tries and aspirational diets in developing countries will not be Agricultural production is estimated to use 70% global fresh- readily achieved. However, the definition of sustainable, diverse water resources from rivers, lakes and groundwater (blue water). diets and socially-acceptable diets is an area that merits consider- These withdrawals produced 20% global food, with the remaining able additional research. 80% produced from rain-fed agriculture (CA, 2007). Further B.A. Keating et al. / Global Food Security 3 (2014) 125–132 129 irrigation development could contribute a pathway to meeting because it is fundamentally focused on lifting the yield potential global food demands in 2050, particularly in regions such as Sub- for a particular production environment. The approach may Saharan Africa given its current low levels of irrigation develop- interact with other pathways but the primary differentiation is ment (IAASTD, 2009). There are pressures (climate change, that the pathway is focused on genetic advance in crops, pastures, resource degradation) on existing irrigation regions and consider- trees or animals using conventional or advanced techniques able uncertainty on the extent to which irrigation can be sustain- (genomics and other -omics). Such advances may offer significant ably expanded to meet future food demand. Hence, increasing the technological breakthroughs in the future, and significantly mod- efficiency of global rain-fed agriculture is also of paramount ify our understanding of how to increase global food production importance for the sustainability of the global food system (CA, (Fedoroff et al., 2010). 2007).

3.3. Pathways that target avoiding losses in current or future 3.2.3. Expanding aquaculture production production potential Currently, fish products account for around 15% animal source food protein globally (WHO/FAO, 2002). Until 2000, two-thirds of 3.3.1. Maintaining control of biotic stresses, biosecurity and food fi fi the global sh supply came from capture sheries in marine and safety inland waters, with aquaculture from both specialised aquaculture While practices for controlling weeds, pests and diseases are fi and integrated crop-livestock- sh farming systems, contributing critical components of current crop and livestock systems, biotic fi the remaining production. While capture sheries have stabilised, stresses are continually evolving and research effort must be fi or in some cases declined, most increases in future sh production maintained to retain even current production levels and reduce will come from aquaculture (Delgado, 2000). Aquaculture can pesticide use (Lewis et al., 1997). Maintaining disease resistance in make use of land and water not otherwise suited to food produc- crop varieties and integrated pest and weed management systems tion provided sustainable feeding systems can be established. that protect against chemical resistance are example imperatives Additionally, aquaculture can be integrated into mixed crop- aimed at avoiding future losses of current productivity. Biosecurity fi ’ livestock and sh systems, improving nutrient cycles and farmers efforts contribute in a similar way by restricting the spread of yield incomes. Currently aquaculture systems and aquaculture might reducing biotic stresses from the spread of pests, diseases and represent one of the pathways rapidly growing in the developing weeds; without them there would be losses in production which world for food security in 2050. would add to the scale of the food security challenge. Finally, maintaining food safety standards will help avoid future losses in 3.2.4. Closing yield gaps in existing crop and livestock production food supply through food safety recalls. systems Yield gaps are defined as the gap between the yields currently being achieved by farmers and the yields that are attainable if 3.3.2. Avoiding land and water degradation existing varieties, technologies and farming practices are adopted Research, management and policy efforts to reduce or avoid (Lobell et al., 2009; Van Ittersum et al., 2013). Yield gaps vary from land and water degradation will contribute to future global as low as 10–20% in developed countries up to 60–80% in some food security by protecting against the loss of current or future developing regions, such as Sub-Saharan Africa (World Bank, productive capacity. This pathway includes efforts aimed at redu- 2008; Foley et al., 2011; Tittonell and Giller, 2013; van Ittersum cing soil degradation processes such as erosion, salinity, acidifica- et al., 2013; Carberry et al., 2013). There are many reasons why a tion, organic matter rundown and compaction, and reduced yield gap might exist and it is not as simple as farmers not being overloads of N and P in groundwater and rivers (Giller et al., willing or able to adopt a set of technologies and practices. Input 2011). Degradation of water supplies used in agriculture, such as or output markets prices, climatic variability or other conditions siltation of dams, is another example of efforts to maintain may make it unattractive for farmers to make the investments or agricultural productive capacity (CA, 2007). take on the risks to close the yield gap. Closing the yield gap within a commodity production system through the application of 3.3.3. Minimising climate change through mitigation existing technologies and knowledge is a potentially important Climate change potentially reduces current agricultural pro- pathway towards food security in 2050. ductivity and in some regions is likely to restrict future production activities. Agricultural emissions contribute gases to the atmo- 3.2.5. Developing new farming systems that intensify land and water sphere that are forcing the global climate. These gases include CH4 use from livestock, N2O from agricultural soils and fertilisers and CO2 fi Evolving new or modi ed farming systems that make more from land clearing and soil organic matter rundown. Reductions fi ef cient and complete use of land and water resources is another in agricultural greenhouse emissions will in part moderate climate food security pathway, differentiated here from closing yield gaps change, acknowledging that major drivers come from other by the novel nature of the system that is developed (Havlik et al., sectors. The estimated technical mitigation potential in the agri- 2013). Double or triple cropping (crop rotations or intercropping) culture, forestry and land use sectors is 1.5–4.3 Gt CO2 eq. per year in a historically single cropping system is one example. Another is for technical options, while those including food demand manage- the introduction of novel cropping elements into historically ment practices could increase this potential to up to 15.3 GtCO2 eq. livestock grazing systems, as often observed in parts of Sub- ( et al., 2013). There is a risk however that some agricultural Saharan Africa (Herrero et al., 2010). This pathway could be mitigation efforts such as reductions in livestock farming, reduc- considered as closing the yield gap through farming systems- tions in N fertiliser use and conversion of agricultural land to level innovations rather than commodity level innovations. carbon forests, might place additional pressures on food security and hamper economic and social land use activities. Hence, 3.2.6. Crop and livestock improvement to lift genetic potential activities that can reduce agricultural emissions without reducing Developing new genetics provides the prospect of lifting yield agricultural production represent another important pathway to ceilings to levels not previously possible for a given production meet the future food security challenge (Havlik et al., 2013; Valin environment. In this way it is different to closing yield gaps et al., 2013). Since all of these activities are largely interconnected, 130 B.A. Keating et al. / Global Food Security 3 (2014) 125–132 it is essential to examine trade-offs between all the strategies Finally, respondents were asked to indicate what perspective implemented. they were applying in their responses – were they considering a specific region, or were they responding from a global perspective. 3.3.4. Adapting to unavoidable climate change Most respondents (49) reported that they used a global perspec- The projected impacts of climate change on agriculture have been tive; one focussed on China, one on South East Asia and the Pacific, estimated to lead to reduced crop and livestock yields, increased two on Australia/New Zealand, 8 on South Asia, and 19 on Sub- prices and trade and an increase in children malnutrition of 20% by Saharan Africa. A further 6 respondents did not answer this 2050 (Nelson et al., 2009). Under these circumstances, efforts that question. can adapt agricultural practices and systems to the unfolding climate The results of the survey are presented in Table 2. In terms of will help reduce the losses of existing and future food production and the relative importance of the three strategies, targeting filling the also curb malnutrition. Nelson et al. (2009) estimated that invest- production gap was ranked as the most important strategy with an ments in adaptation practices up to US$7.3 billion would be needed average rated contribution of 46%. The expressed contributions to reduce the impacts of climate change on agriculture. from avoiding reductions in the future production potential and food demand management are 33.6% and 20.4% respectively. This result is not surprising as there seems to be significant evidence 4. A survey on prospects for the solution pathways coming from the integrated assessment studies (Foresight, 2010; IAASTD, 2009; Nelson et al., 2009) showing the beneficial impact In the absence of a comprehensive global food system model that and great scope for increasing productivity, especially in the is adequate to assess the significanceofalltheproposedpathways,we developing world (World Bank, 2008). conducted a survey of 86 experienced stakeholders in the field of In terms of individual pathways, several observations can be agriculture and food security research to establish what they thought made. Not one single pathway overwhelmingly dominates the were the most important pathways for feeding the world in the future. solution space, although closing yield gaps was ranked the highest The survey was anonymous but respondents could separately with 14.8% relative contribution. The highest rated pathways come provide an email contact to facilitate sharing of results. Survey from different strategies. Stakeholders consider that food security recipients were briefed on the conceptual framing of the analysis will result from combinations of pathways – for example, exploiting as described in this paper and asked to assess “the relative yield gaps, avoiding soil and water degradation, adapting to climate contribution that will be made by each of the three general change and simultaneously developing new farming systems. This is strategies for meeting food demand”. In answering this question, an important finding as it shows that investing in the future of respondents were asked to “consider both the technical/bio- agriculture will require a balanced portfolio approach. physical potential and the social/economic feasibility of the Interestingly, our expert panel considered expanding land and different strategies”. Views on relative contribution were assessed water resources would contribute on average 8.5% of the solution via the distribution of 100 points across the three overall strategies – a low number at first glance but not completely out of line with initially and subsequently a second round of voting allocated 100 the 11–20% arable land expansion seen over the 1970–2010 period. points to the pathways nominated within each strategy. The final A surprising result is that only 7.3% of the allocated solution was rated contribution of individual pathways was calculated as the aligned to lifting crop or livestock genetic potential. This may reflect a product of the overall strategy percentage and the individual paucity of crop and livestock breeders in the expert panel, although pathway percentage. This calculation results in a total of 100 this contribution doubled to 15.4% if the maintenance of pest and percentage points being allocated by each expert. Respondents disease resistance is regarded as largely a genetic improvement issue. could allocate zero points to strategies or pathways considered In contrast, pathways with a stronger agronomic focus (closing yield irrelevant and could nominate and vote points against new path- gaps, intensifying farming systems, avoiding soil and landscape ways if they felt the 14 pathways proposed (Table 2) missed a degradation) accounted for 34.3% of overall allocations on average. pathway or more. Finally, participants were asked to nominate Climate change adaptation and mitigation responses that avoid their field of expertise, years of experience and geographical future losses of current productivity amounted to an average 14.6% perspective that shaped their responses. contribution to future food security. The respondents reported a range of professional backgrounds. There was considerable diversity in individual responses with Thirteen worked in agricultural policy development, 21 in agricultural approximately normal distributions and standard deviations were productivity research, 1 in crop/pasture/tree/livestock breeding, 1 as a in the order of 5 to 10 percentage points in the vote allocation. donor/investor in agricultural productivity, 5 in food/nutrition research The 14 nominated pathways received over 98% of the allocated and development, 22 in natural resource management or environ- votes. A small number of respondents voted points against additional mental research, 11 in research management, and 6 as some other nominations, the most common being control in the growth of the category. A further 6 respondents did not report their background. We human population. Other nominations included novel foods such as could detect no significant differences in the average ratings of insect or bio-engineered foods (artificial meat as an example). strategies and pathways across these different backgrounds. The analyses showed some differences in average ratings of path- Respondents also indicated their years of experience in their ways depending on the respondents’ perspective. There was one profession. One reported fewer than 5 years experience, 12 significant effect for Pathway 6 (Expanding the water resources used reported 5–10 years, 8 reported 11–15 years, 14 reported 16–20 for agricultural irrigation): respondents focussing on sub-Saharan years, and the majority (45) reported more than 20 years of Africa rated this strategy as more important than did than other experience. Six people did not provide a response to this question. respondents. There was also a marginally significant effect for Pathway With two exceptions, no significant differences in the average 12 (Avoiding soil and water degradation): respondents using a global ratings of strategies provided by respondents with different levels focus rated this strategy as less important than other respondents. of experience were observed. There were two marginally signifi- cant effects, however. Respondents with lower levels of experience tended to provide slightly higher ratings of importance for Path- 5. Conclusions way 13 (minimising climate change through mitigation that maintains food security), and slightly higher ratings for Strategy The Pacala and Socolow (2004) analysis demonstrated there are C (avoiding losses in current or future production potential). no “silver bullets” in the armoury to address the greenhouse gas B.A. Keating et al. / Global Food Security 3 (2014) 125–132 131 stabilisation challenge and concerted effort across the suite of prevents us from acknowledging them in person. The survey options is critical if the challenge is to be met. A similar result was component of this work was conducted under the guidance and obtained from our stakeholder consultation. A lesson from this approval of the CSIRO Ethics in Social Research Committee. work is that elegant simplicity that assists in communication of concepts and breaks a big complex and somewhat amorphous References challenge down to more easily understood parts is very valuable.

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