The resilience of these dynamics directly depends on the globalization of food through trade, including the amount of food traded, the number of links describing trade between countries, and the topological properties of the trade network. Using reconstructions of food production and trade based on FAO data , this analysis shows that in the past few decades the system has become increasingly vulnerable to instability as an effect of demographic growth, dietary shifts, and the increasing inter connectedness of the trade network. Indeed, some nodes are starting to show the first episodic signs of instability, particularly in water-poor and trade-dependent countries . This analysis of the long-term response to shocks is in agreement with the short-term propagation of perturbations in the trade network during a food crisis ; both approaches have shown how the fragility of the coupled food-demographic system has increased as an effect of the growing globalization of food through trade. If trade and interconnectedness have the effect of reducing the resilience of the system as a whole, it is paramount to investigate to what extent it would be possible to globalize without becoming more vulnerable. A possible solution of this problem is suggested by ecological systems, which often exhibit some degree of modularity.There is evidence that systems with a modular structure—that is, with groups of countries that interact more among themselves than with countries from other modules—are able to contain the spread of perturbations within the targeted module, whereas the other modules remain only marginally impacted . In other words, the modules act directly to buffer the propagation of shocks to other communities, thereby increasing the stability and resilience of the entire system . Interestingly,tower garden the virtual water trade network exhibits a growing degree of modularity with a ratio between internal and external fluxes that is approaching 70% . To date, however, the effect of modularity still needs to be investigated in the context of the resilience of trade and food security.
An alternative approach to understand the impact of virtual water trade on population growth is through carrying capacity plots , which distinguish different strategies and their success by showing the historical evolution of a region or population’s local food supply potential and net food imports relative to their local and post trade carrying capacity. Porkka and collaborators confirm that food import is the strategy nearly universally used to overcome local limits to growth. Nevertheless, they also highlight that these strategies are implemented to varying extent and with varying success . Therefore, whether dependency on imports is necessary and desirable, a clear policy priority at both local and global scale is needed and it ideally would attempt to keep the demand of food under control .There is wide agreement that humanity’s rate of resource use exceeds what can be sustainably generated and absorbed by Earth’s systems . Substantial uncertainty persists for an apparently basic question—by how much is food demand likely to grow in the coming decades—with estimates typically ranging from a required 60% to 110% increase by the year 2050 over circa year 2005 levels . More recently, Hunter et al. estimated that an increase in cereals production of 25–75% over 2014 levels could be sufficient to satisfy projected demand in 2050. The breadth of future GHG emissions trajectories—and the magnitude of their cascading consequences for agricultural productivity—leaves considerable unknowns regarding future food production under a changing climate . A radical transformation of the global food system is likely required in order to increase production while faced with the considerable uncertainties related to demand and climate impacts. New strategies for achieving FEW security worldwide may benefit from adoption of an integrated approach aimed at an improvement in the availability, access, and nutritional properties of food while enhancing the provision of affordable, clean, and reliable energy . Moreover, a secure FEW system will incorporate a sustainable use of natural resources, maintain environmental stream flows, and restore ecosystem services.
The FEW system will need to invert the ongoing trend of increasing vulnerability and enhance its resilience with respect to climate shocks, demographic growth, and consumption trends. The previous sections have highlighted the existence of several major challenges in this multi-objective strategy to food, water, and energy security. For instance, the sustainability of energy production can be improved by increasing the reliance on renewable energy sources, which would decrease the rate of fossil fuel depletion, reduce CO2 emissions, and consequently allow societies to improve their ability to meet climate change targets. Renewable energy sources based on bio-fuels, however, would claim huge volumes of water and large expanses of land, thereby inevitably competing with the food system . Moreover, bio-fuel production often entails direct and indirect land use change and associated GHG emissions, indicating that in the short term these energy sources might have a negative impact on the environment . Nonfuel-based renewable energy production may also require substantial amounts of water and therefore compete with food crops in water-stressed regions . The increasing demand for food and energy by the growing and increasingly affluent human population can hardly be met with the limited land and water resources of the planet unless we transform the FEW system. As noted in the previous sections, approaches focusing on ways to increase food and energy production instead of curbing the demand would ignore the existence of limits to growth imposed by the natural resources the planet can provide and are likely to achieve higher production rates at huge environmental costs , resilience losses , and increased food insecurity for the poor. To be sure, there are still margins for increased production through improvements in efficiency, technological innovation, and agroecologically efficient farming systems, but these measures are likely to be insufficient to meet long-term global food and energy security needs . There is the need for a complete rethinking of the FEW system to develop a comprehensive strategy for food, water, and energy security, based on enhancing the production and moderating the demand . Although a conclusive answer to the question of how to sustainably meet the food, energy and water needs of the rising and increasingly demanding human population is still missing, here we review a number of new and old approaches and ideas that could contribute to future food, water, and energy security.
Such approaches can be, in general, technological , cultural , or institutional .Large yield gaps, or the difference, between current and attainable yields still exist in many parts of the world, particularly in sub-Saharan Africa and offer the potential to increase global production of major crops by as much as 58% under currently available technologies and management practices . There is broad consensus that efforts to enhance crop yields on currently cultivated lands are crucial for avoiding additional agricultural expansion , the consequences of which would be profound and undesirable for natural systems and functioning . Agricultural intensification, however, is not free of environmental impacts in that it contributes to GHG emissions, freshwater and coastal water pollution, depletion of freshwater resources, and consequent loss of aquatic habitat . In light of the environmental impacts of conventional intensification, some scientists are advocating for an approach to food security that relies on a “sustainable intensification” of agriculture , which aims to close the yield gap while minimizing the environmental impacts . Moreover, as with historical yield trends, stacking flower pot tower harvest frequencies have generally increased through time, but many places with the potential to transition to double-cropping systems have yet to do so . On the one hand, yield and harvest gap closure offers great promise for increasing the food self-sufficiency of many developing nations because the areas with the largest potential for production increases are those places that currently rely heavily on food imports and have some of the highest rates of projected population growth to mid century . On the other hand, these remaining yield gaps raise questions about how best to promote the diffusion of high-yielding crop varieties and agricultural technologies, given that these agricultural advancements have yet to reach many places even 50 years after the start of the green revolution . Moreover, it is unclear whether additional inputs are adequately available in low-yield areas and, if so, how to avoid their unsustainable use . Thus, particularly with regard to non-mobile resources, such as land and water, it will likely be essential to ensure that increases in production occur in places where and when natural resources can support it . There are social, economic, and institutional factors that need to be accounted for while advocating for agricultural intensification versus alternative farming approaches . Most of the existing literature on this subject has recognized the pros of yield gap closure as an alternative to agricultural expansion at the expense of natural ecosystems , particularly in the tropics . “Land sparing” can, in many contexts, minimize habitat losses, land degradation, CO2 emissions, and declines in biodiversity . This approach, however, is not a panacea because its profound social impacts have often been overlooked by focusing on agrotechnological solutions without considering their effect on production systems, such as smallholder farmers . Intensification efforts require investments that are increasingly made by large-scale agribusiness corporations, particularly in the developing world. Such investments may affect the system of production and its inputs, for example, through contract farming or out grower schemes or land use, access, and tenure rights, as occurs for LSLAs , which are discussed in section 9.3. Agricultural intensification is most effective in countries where relatively large yield gaps still exist, such as sub-Saharan Africa, while ensuring that new fertilizer and water are used in the most efficient way possible . To boost crop yields, investment in modern agricultural technology is required, which many rural communities in lower-income countries cannot afford. If neither local land users nor domestic investors are able to improve crop yields, in years of increasing crop prices, foreign corporations or foreign-domestic joint ventures are not likely to miss the profit opportunities existing in under performing agricultural land .
Indeed, recent years have seen a wave of investments in agricultural land in the developing world, with import-dependent nations seeking to increase the pool of land and water resources under their control and targeted countries pursuing avenues to promote rural development and agricultural technology transfers . However, there is a growing body of scientific and anecdotal evidence showing that the development and food security goals of these land deals are often not achieved and, instead, often bring substantial social and environmental consequences . Such land deals ultimately may result in the displacement of subsistence or small-holder farmers by large-scale commercial agriculture, as well as the development of new agricultural land at the expense of savannas, forests, or other ecosystems . Because most of the cultivated land worldwide is managed by small-scale farmers , this ongoing shift in systems of production may strongly reshape the agrarian landscape around the world with important impacts on rural livelihoods because it increases the dependence on a volatile food market. Thus, agricultural intensification may be the result of important transformations in land tenure, farming systems, and livelihoods. Developing countries may enhance crop yields by introducing modern agricultural technology while promoting greater efficiency in food production through a transition in their agricultural sector toward commercial-scale farming. Commercial agriculture lends itself better to capital inputs from investors and could result from LSLAs or other forms of investment, such as contract farming , or mixed out grower schemes . However, there could be negative impacts on rural communities and their livelihoods because LSLAs may turn farmers into employees and increase their vulnerability to food price volatility The transition to large-scale farming, however, might be unnecessary: small-scale farms, which account for most of the global calorie and nutrient production , can be very productive. There is evidence in the economic literature about the inverse relationship between farm size and productivity, meaning that smallholder farmers, when provided with adequate inputs, may often achieve yields that outperform commercial, large-scale agriculture. Identifying mechanisms that support yield enhancements, technology transfers, and secure land tenure to these critical stakeholders is a key component of advancing global food security, promoting poverty alleviation, and enhancing food system resilience. Overall, intensification typically requires the introduction of modern green revolution technology in areas of the developing world in which relatively large yield gaps exist.