► The food system contributes substantially to global greenhouse gas emissions. ► Technological mitigation approaches, while necessary, may not be sufficient. ► Dietary shift away from meat and dairy products is also needed. ► This could yield health benefits for developed world consumers. ► But it would pose major nutritional challenges for developing countries. ► A nutrition oriented agriculture that sits within environmental limits is needed. This paper reviews estimates of food related greenhouse gas (GHG) emissions at the global, regional and national levels, highlighting both GHG-intensive stages in the food chain, and GHG-intensive food types. It examines approaches that have been proposed for mitigating emissions at each stage in the chain and looks at how these sit within wider discussions of sustainability. It finds that efficiency-focused technological measures, while important, may not only be insufficient in reducing GHGs to the level required but may also give rise to other environmental and ethical concerns. It gives evidence showing that in addition to technological mitigation it will also be necessary to shift patterns of consumption, and in particular away from diets rich in GHG-intensive meat and dairy foods. This will be necessary not just in the developed but also, in the longer term, in the developing world. This move, while potentially beneficial for food secure, wealthier populations, raises potentially serious nutritional questions for the world’s poorest. A priority for decision makers is to develop policies that explicitly seek to integrate agricultural, environmental and nutritional objectives.
► Nitrogen fertiliser inputs to agriculture are essential for global production of sufficient food. ► Methane is the most efficient hydrogen feedstock and energy source for nitrogen fixation, and reserves should be protected in the absence of alternative hydrogen sources. ► Current known and potential reserves of phosphate rock are quantified. ► The requisite aggregate annual intake of phosphorus in food by the global population is estimated. ► It is essential that phosphorus is recycled to avoid exhaustion of reserves of this unsubstitutable nutrient. Without the input of fertiliser nitrogen it is estimated that only about half of the current global population can be supplied with sufficient food energy and protein. The anticipated increase in the population to 2050 will increase the dependency on fertiliser inputs. The paper examines the different potential sources of energy and hydrogen required for this essential fixation of atmospheric nitrogen into plant-available nitrogenous fertiliser and concludes that methane from natural gas is clearly the most suitable source. In the absence of a cost-effective alternative source of hydrogen it is recommended that an on-going requirement for methane is acknowledged and that consideration be given to strategic reserves for the production of food. Phosphorus is also an essential and unsubstitutable nutrient for plants and animals, but while the global reserves of atmospheric nitrogen are effectively unlimited, the reserves of phosphate rock are finite. Recent estimates of the reserve suggest that at the current rate of use this resource will become exhausted within some hundreds of years. The annual increment of phosphorus contained in the human population is estimated to be in the order of 1 Mt/yr, which is a small proportion of the quantity mined. There is a clear requirement to ensure that phosphorus is recycled to a large extent, so that the rate of exhaustion of the reserves of phosphate rock is significantly reduced. Legislation relating to the management of phosphorus appears entirely associated with its potential to upset natural ecosystems, with apparently no regulations yet requiring the efficient use and reuse of a scarce resource.
► An integrated analytical framework addresses competition for land arising from the ‘energy-food-environment’ trilemma. ► Land-use change risks from increasing demand for food are at least as great as those from biofuels. ► Biofuels and biomaterials are destined to be globally significant technologies for many decades. ► Strategic political direction of innovation is necessary to achieve sustainable intensification of agriculture. The paper addresses the new competition for land arising from growing and changing demand for food when combined with increasing global demand for transport energy, under conditions of declining petro-chemical resources and the urgent need to reduce greenhouse gas emissions. The paper starts from the premise of a ‘food, energy and environment trilemma’ ( ), where all demands to expand the area of cultivated land present high risks of increasing the carbon footprint of agriculture. Having reviewed the main drivers of demand for food and for liquid transport fuels, the paper weighs the controversies surrounding biofuels arising from food-price spikes, the demand for land, and consequent direct and indirect land-use change. It suggests that we need a more complex, and geographically differentiated, analysis of the interactions between direct and indirect land-use change. The paper then reviews evidence of land availability, and suggests that in addition to technical availability in terms of soil, water, and climate, political, social, and technological factors have significantly shaped the competition for land in different global regions, particularly the three major biofuel producing ones of the USA, Brazil and Europe. This point is further developed by reviewing the different innovation pathways for biofuels in these three regions. The main conclusion of this review is firstly that any analysis requires an integrated approach to the food-energy-environment trilemma, and secondly that strategic political direction of innovation and sustainability regulation are required to bring about major shifts in agriculture leading to sustainable intensification of cultivation ( ), rather than the continued expansion of cultivated area. The consequent perspective is one of considerable global variety in technologies, agricultural productive systems, and use of natural resources. This contrasts sharply with the world of a dominant global and integrated technology platform based on petro-chemicals to which we have become accustomed.
► We review soil issues relevant to global food security and ecosystem functioning. ► We suggest actions for each issue including policies, communication or research. ► Organic matter content is essential for improving many soil physical properties. ► Policies to make fertilizers affordable in developing countries are essential. ► Practices to cut greenhouse gas emissions from intensified agriculture are needed. Requirements for research, practices and policies affecting soil management in relation to global food security are reviewed. Managing soil organic carbon (C) is central because soil organic matter influences numerous soil properties relevant to ecosystem functioning and crop growth. Even small changes in total C content can have disproportionately large impacts on key soil physical properties. Practices to encourage maintenance of soil C are important for ensuring sustainability of all soil functions. Soil is a major store of C within the biosphere – increases or decreases in this large stock can either mitigate or worsen climate change. Deforestation, conversion of grasslands to arable cropping and drainage of wetlands all cause emission of C; policies and international action to minimise these changes are urgently required. Sequestration of C in soil can contribute to climate change mitigation but the real impact of different options is often misunderstood. Some changes in management that are beneficial for soil C, increase emissions of nitrous oxide (a powerful greenhouse gas) thus cancelling the benefit. Research on soil physical processes and their interactions with roots can lead to improved and novel practices to improve crop access to water and nutrients. Increased understanding of root function has implications for selection and breeding of crops to maximise capture of water and nutrients. Roots are also a means of delivering natural plant-produced chemicals into soil with potentially beneficial impacts. These include biocontrol of soil-borne pests and diseases and inhibition of the nitrification process in soil (conversion of ammonium to nitrate) with possible benefits for improved nitrogen use efficiency and decreased nitrous oxide emission. The application of molecular methods to studies of soil organisms, and their interactions with roots, is providing new understanding of soil ecology and the basis for novel practical applications. Policy makers and those concerned with development of management approaches need to keep a watching brief on emerging possibilities from this fast-moving area of science. Nutrient management is a key challenge for global food production: there is an urgent need to increase nutrient availability to crops grown by smallholder farmers in developing countries. Many changes in practices including inter-cropping, inclusion of nitrogen-fixing crops, agroforestry and improved recycling have been clearly demonstrated to be beneficial: facilitating policies and practical strategies are needed to make these widely available, taking account of local economic and social conditions. In the longer term fertilizers will be essential for food security: policies and actions are needed to make these available and affordable to small farmers. In developed regions, and those developing rapidly such as China, strategies and policies to manage more precisely the necessarily large flows of nutrients in ways that minimise environmental damage are essential. A specific issue is to minimise emissions of nitrous oxide whilst ensuring sufficient nitrogen is available for adequate food production. Application of known strategies (through either regulation or education), technological developments, and continued research to improve understanding of basic processes will all play a part. Decreasing soil erosion is essential, both to maintain the soil resource and to minimise downstream damage such as sedimentation of rivers with adverse impacts on fisheries. Practical strategies are well known but often have financial implications for farmers. Examples of systems for paying one group of land users for ecosystem services affecting others exist in several parts of the world and serve as a model.
► We review the land sparing vs. wildlife-friendly farming debate. ► Few appropriate data exist: we detail what data are required. ► Wildlife-friendly farming is ineffective for many wild species. ► Conserving many species will depend on restricting global agricultural expansion. ► Effective land sparing requires both habitat protection and yield increases. Should farming and conservation policies aim broadly to separate land for nature and land for production (land sparing) or integrate production and conservation on the same land (wildlife-friendly farming)? Most studies that try to address this question suffer from flaws in sampling design, inappropriate metrics, and/or failure to measure biodiversity baselines. We discuss how these failings can be addressed, and what existing information tells us about the key debates on this topic. The evidence available suggests that trade-offs between biodiversity and yield are prevalent. While there are some wildlife-friendly farming systems that support high species richness, a large proportion of wild species cannot survive in even the most benign farming systems. To conserve those species, protection of wild lands will remain essential. Sustainable intensification could help to facilitate sparing of such lands, provided that as much attention is given to protecting habitats as to raising yields. We discuss the general circumstances under which yield increases can facilitate land sparing, recognising that policies and social safeguards will need to be context-specific. In some situations, bringing degraded lands into production could help reduce pressure on wild lands, but much more information is needed on the biodiversity implications of using degraded lands. We conclude that restricting human requirements for land globally will be important in limiting the impacts on biodiversity of increasing food production. To achieve this, society will need to integrate explicit conservation objectives into local, regional and international policies affecting the food system.
► The study addresses the potential and challenges of carbon sequestration in agricultural soils. ► Technical potential of C sequestration is 1.2-3.1Gt/yr. ► Increasing C pool in the root zone by 1t/yr can increase production in developing countries by 24-32 million t/yr for food grains and 6-10 million t/yr for roots and tubers. ► The strategy is to adopt conservation tillage, cover cropping, manuring, agroforestry, biochar and other amendments. ► Rather than subsidies, adoption of these technologies can be promoted by payments for ecosystem services. Soils of the world’s agroecosystems (croplands, grazing lands, rangelands) are depleted of their soil organic carbon (SOC) pool by 25–75% depending on climate, soil type, and historic management. The magnitude of loss may be 10 to 50 tons C/ha. Soils with severe depletion of their SOC pool have low agronomic yield and low use efficiency of added input. Conversion to a restorative land use and adoption of recommended management practices, can enhance the SOC pool, improve soil quality, increase agronomic productivity, advance global food security, enhance soil resilience to adapt to extreme climatic events, and mitigate climate change by off-setting fossil fuel emissions. The technical potential of carbon (C) sequestration in soils of the agroecosystems is 1.2–3.1 billion tons C/yr. Improvement in soil quality, by increase in the SOC pool of 1 ton C/ha/yr in the root zone, can increase annual food production in developing countries by 24–32 million tons of food grains and 6–10 million tons of roots and tubers. The strategy is to create positive soil C and nutrient budgets through adoption of no-till farming with mulch, use of cover crops, integrated nutrient management including biofertilizers, water conservation, and harvesting, and improving soil structure and tilth.
► We conducted a nation-wide choice experiment to assess consumer preference for food safety attributes in urban China. ► We model heterogeneity in consumer preferences using a random parameters logit and latent class model. ► We find that consumers value direct government involvement in the food safety system more over other options. Food safety issues often arise from asymmetric information between consumers and suppliers with regards to product-specific attributes. Severe food safety scandals were observed recently in China. These events not only caused direct economic and life losses, but also created distrust in the Chinese food system domestically, as well as internationally. While much attention has focused on the problems plaguing the Chinese government’s food inspection system, little research has been dedicated to analyzing Chinese consumers’ concerns surrounding food safety. In this paper, we measure consumer preferences for select food safety attributes in pork and take food safety risk perceptions into account. Several choice experiment models, including latent class and random parameters logit, are constructed to capture heterogeneity in consumer preferences. Our results suggest that Chinese consumers have the highest willingness-to-pay for a government certification program, followed by third-party certification, a traceability system, and a product-specific information label. The results of this study call for the direct involvement of the Chinese government in the food safety system. A stricter monitoring system will not only improve consumer well-being in the short-run, but also restore consumers’ trust leading to a social welfare increase in the long run.
► We studied environmental impacts of food production and transport. ► Protein efficiency in terms of energy used and emissions of GHGs were obtained. ► Protein efficiency was much higher for plant-based foods than for animal-based. ► Plant-based protein efficiency increases with increasing protein content of the food. ► A more vegetarian diet greatly decreases impacts to feed a growing world population. The production, transport and processing of food products have significant environmental impacts, some of them related to climate change. This study examined the energy use and greenhouse gas emissions associated with the production and transport to a port in Sweden (wholesale point) of 84 common food items of animal and vegetable origin. Energy use and greenhouse gas (GHG) emissions for food items produced in different countries and using various means of production were compared. The results confirmed that animal-based foods are associated with higher energy use and GHG emissions than plant-based foods, with the exception of vegetables produced in heated greenhouses. Analyses of the nutritional value of the foods to assess the amount of protein delivered to the wholesale point per unit energy used or GHG emitted (protein delivery efficiency) showed that the efficiency was much higher for plant-based foods than for animal-based. Remarkably, the efficiency of delivering plant-based protein increased as the amount of protein in the food increased, while the efficiency of delivering animal-based protein decreased. These results have implications for policies encouraging diets with lower environmental impacts for a growing world population.
► US and Thai monthly export data used to re-examine causes of global food crisis. ► Export restrictions and demand surges explain nearly all of surge in rice prices. ► Droughts, export restrictions and demand surges a major factor in wheat markets. ► Trade shocks even a major factor for maize, and soybean prices followed maize prices in the future more emphasis should be placed on trade-based policy solutions. Although fundamental factors were clearly responsible for shifting the world to a higher food price equilibrium in the years leading up the 2008 food crisis, there is little doubt that when food prices peaked in June of 2008, they soared well above the new equilibrium price. Numerous arguments have been proposed to explain overshooting, including financial speculation, depreciation of the United States (US) dollar, low interest rates, and reductions in grain stocks. However, observations that international rice prices surged in response to export restrictions by India and Vietnam suggested that trade-related factors could be an important basis for overshooting, especially given the very tangible link between export volumes and export prices. In this paper, we revisit the trade story by closely examining monthly data from Thailand (the largest exporter of rice), and the United States (the largest exporter of wheat and maize and the third largest exporter of soybeans). In all cases except soybeans, we find that large surges in export volumes preceded the price surges. The presence of these large demand surges, together with back-of-the-envelope estimates of their price impacts, suggests that trade events played a much larger and more pervasive role than previously thought.
► A survey of 428 supermarket shoppers evaluated the use of environmental food labels. ► Consumer demand is strong for carbon labels but interpretation can be confusing. ► Younger consumers favour of carbon labels most, but for within-product comparisons. ► The success of policy initiatives is limited whilst relying on consumer responsibility. ► More effective linkages between food policy and food market actors are needed. Both the process of carbon footprinting and carbon labelling of food products are currently voluntary in the UK. Both processes derive from the UK’s policy for sustainable development and in particular, the UK’s Framework for Environmental Behaviours that strongly advocates a social marketing approach towards behavioural change. This paper examines whether carbon footprinting and labelling food products, borne from an overarching policy imperative to decarbonise food systems, is a tool that will actively facilitate consumers to make ‘greener’ purchasing decisions and whether this is a sensible way of trying to achieve to a low carbon future. We do so by drawing from a survey exploring purchasing habits and perceptions in relation to various sustainability credentials of food products and particularly ‘carbon’, using a combination of descriptive and cluster analysis. The data, from 428 UK supermarket shoppers, reveals that whilst consumer demand is relatively strong for carbon labels with a stated preference rate of 72%, confusion in interpreting and understanding labels is correspondingly high at a total of 89%, primarily as a result of poor communication and market proliferation. Three statistically distinct clusters were produced from the cluster analysis, representing taxonomies of consumers with quite different attitudes to carbon and other wider sustainability issues. Whilst the majority of consumers are likely to react positively to further carbon labelling of food products, this in itself is unlikely to drive much change in food systems. As such, the data imply that a concerted policy drive to decarbonise food systems via voluntary carbon footprinting and labelling policy initiatives is limited by a fragmented and haphazard market approach where retailers are being careful not to disaffect certain products by labelling others within the same category. Consumers may want to make choices based on the carbon footprint of products but do not feel empowered to do so and relying on consumer guilt is inappropriate. The paper concludes that the establishment of effective linkages between food policy and food market actors to drive a targeted and coherent carbon labelling policy is needed. This would provide consumers with the opportunity to make informed choices, especially within food product categories and negate the need for retailers to depend on the demand side of the supply chain to achieve carbon reduction targets.
► Low irrigation contributes to Sub-Saharan Africa’s low agricultural productivity. ► We assess area potential with a combined bio-physical and socioeconomic analysis. ► We find profitable expansion potential of 24 million ha over the next 50 years. ► This is a 177-percent increase over existing area of 13 million hectares. ► Both small- and large-scale irrigation are profitable. Although irrigation in Africa has the potential to boost agricultural productivities by at least 50%, food production on the continent is almost entirely rainfed. The area equipped for irrigation, currently slightly more than 13 million hectares, makes up just 6% of the total cultivated area. More than 70% of Africa’s poor live in rural areas and mostly depend on agriculture for their livelihoods. As a result, agricultural development is key to ending poverty on the continent. Many development organizations have recently proposed to significantly increase investments in irrigation in the region. However, the potential for irrigation investments in Africa is highly dependent upon geographic, hydrologic, agronomic, and economic factors that need to be taken into account when assessing the long-term viability and sustainability of planned projects. This paper analyzes the large, dam-based and small-scale irrigation investment potential in Africa based on agronomic, hydrologic, and economic factors. We find significant profitable irrigation potential for both small-scale and large-scale systems. This type of regional analysis can guide distribution of investment funds across countries and should be a first step prior to in-depth country- and local-level assessment of irrigation potential, which will be important to agricultural and economic development in Africa.
► Article looks into the development of the Chinese dairy sector since 2000 in relation to food safety. ► Problems caused by melamine contamination are linked to unregulated development of dairy sector. ► China faced with demands to upgrade its regulatory framework to meet international standards. ► A reform of the dairy sector as well as public food safety control agencies is called for. ► Official controls will have to increase in number from the currently very low levels. ► Costs and benefits outlined by benchmarking, i.e. by comparing the situation in China with that in EU. This article examines the development of the Chinese dairy sector since 2000 and investigates how this has affected food safety. The ongoing problems caused by melamine contamination are linked to the rapid and unregulated development of this sector. Currently, China is faced with demands – both from home and abroad – to improve its food safety record. This will necessitate it upgrades its regulatory framework to meet the standards of Codex Alimentarius and the EU. A serious restructuring of the dairy sector as well as of the public food safety control agencies is called for. The costs and benefits to be accrued by these reforms are the subject of this article.
► Common metrics of food insecurity and undernutrition are critically reviewed. ► Particular focus on FAO approach, food consumption surveys, and anthropometrics. ► All have methodological/empirical problems; true extent of undernutrition is unknown. ► Concrete suggestions for improvement and further research are made. ► Key component is more household surveys linking food consumption and anthropometry. In this article, we critically review the three most common approaches of assessing chronic food insecurity and undernutrition: (i) the FAO indicator of undernourishment, (ii) household food consumption surveys, and (iii) childhood anthropometrics. There is a striking and worrying degree of inconsistency when one compares available estimates, which is due to methodological and empirical problems associated with all three approaches. Hence, the true extent of food insecurity and undernutrition is unknown. We discuss strengths and weaknesses of each approach and make concrete suggestions for improvement, which also requires additional research. A key component will be the planning and implementation of more comprehensive, standardized, and timely household surveys that cover food consumption and anthropometry, in addition to other socioeconomic and health variables. Such combined survey data will allow much better assessment of the problems’ magnitude, as well as of trends, driving forces, and appropriate policy responses.
► Biofuels are important components for future transport energy demand. ► Biofuels are produced from conventional crops (‘first generation’) and ‘new’ biomass sources (‘second generation’). ► Co-products from 1G crops and efficient biorefining of 2G biofuels enhance fuel GHG savings vs fossil fuels. ► Competitive and synergistic interactions can exist between biofuel production and food agriculture. ► Policy development that seeks to deliver both sustainable fuel and food production is currently a major international focus. The potential global demand for biofuels and the implications of this for land use and its interaction with food agriculture is reviewed. It is expected that biofuels will form an important element of global transport energy mix (in the order of 20–30% of total requirement) over the next 40 years and beyond. Over this time, there will be a transition from so called first generation biofuels, based on commodity agricultural crops with food/feed uses, to advanced biofuels, sometimes called second and third generation biofuels, based primarily upon lignocellulosic feedstocks. It remains unclear whether these advanced biofuels, based on lignocellulosic materials, will entirely replace first generation or if second generation will be supplemental to first generation. This expansion in biofuels will be coupled to a substantial increase in alternative fuels (electricity, hydrogen, biogas and natural gas) and modal shifts. Biofuel production from agricultural commodity crops that exhibit strong sustainability criteria will remain important (e.g. sugarcane) with supportive and competitive aspects for food security. Land requirement projections estimated for a range of potential biofuel development trajectories range widely and are inherently uncertain. Under the most active scenario that delivers substantive greenhouse gas reductions in transport by 2050 (relative to 2005 levels), approximately 100 Mha of additional land is projected. In the ‘business-as-usual’ scenario, in which transport energy demand rises by 80% by 2050 from present levels, a land use requirement of 650 Mha is projected. Significant potential exists for producing biofuels that possess high productivity and sustainability profiles through continued research, development and demonstration. Policy and regulation at a global level, that focuses biofuel development on these goals in ways that are synergistic with food agriculture, will simultaneously help to decarbonise transport and maintain a diverse and financially robust agricultural (and forestry) sector.
► We analyze the role of contracts for market channel choices of farmers. ► Modern market channels mostly work with contracts; village traders purchase without. ► There are significant differences between marketing channels and contract features. ► Farmers generally prefer non-contract marketing options. ► Certain factors like provision of inputs increase the attractiveness of contracts. There is an emerging body of literature analyzing how smallholder farmers in developing countries can be linked to modern supply chains. However, most of the available studies concentrate on farm and farmer characteristics, failing to capture details of institutional arrangements between farmers and traders. Moreover, farmers’ preferences have rarely been considered. Here, we address these gaps by analyzing different market channels for sweet pepper in Thailand. Using data from a survey and choice experiment with farmers, we find that there is a general preference for marketing options that do not involve a contract. Additional provision of inputs and credit can increase the attractiveness of contracts. Yet, the most important factor for farmers is to personally know the buyer they deal with, which may be related to issues of trust. Some policy implications are discussed.
This paper examines the impact of non-farm work on household income and food security among farm households in the Northern Region of Ghana. We analyze the impact by employing propensity score matching method that accounts for self-selection bias. The matching results show that participation in non-farm work exerts a positive and statistically significant effect on household income and food security status, supporting the widely held view that income from non-farm work is crucial to food security and poverty alleviation in rural areas of developing countries.
► Resource scarcity rarely leads to food and water wars. ► Water and food insecurity are mostly explained by power and gender relations. ► Food/water security through global trade is called into question by various policy initiatives. ► Water and food management will face major challenges and uncertainties due to climate change. This article looks at the interrelationship between water and food security. More specifically, it examines the resilience and sustainability of water and food systems to shocks and stresses linked to different levels and intensity of conflict, global trade and climate change. The article makes four points: (1) that resource scarcity as a driver of conflict is inconclusive especially at regional and national levels (2) most insecurities surrounding water and food are explained by political power, social and gender relations; (3) global trade has enabled national food and water security, but that is now threatened by increasing food prices, food sovereignty movements and land ‘grabbing’ (4) and that water and food security will face major challenges under conditions of climate change.
► Third party certification (TPC) may impact catfish farmers in Vietnam and Bangladesh. ► We assess the implications of TCP for catfish producers and the environment. ► Environmental gains from TPC are likely to be somewhat limited. ► Inequalities in market access are likely to deepen among Vietnamese producers. ►TPC supports the interests of food buyers and standard setting organisations. Certification is an increasingly pervasive form of market governance through which retailers and NGOs are able to exert control over producers of primary products in order to secure their commercial and institutional interests. This paper assesses the likely outcomes of emerging certification standards intended to govern production of a new global commodity, Pangasius catfish. This evaluation focuses on Pangasius producers in Vietnam and Bangladesh, and one of the key areas which standards seek to regulate; the environment. We conclude that certification is likely to result in greater differentiation and polarisation between larger and smaller farm operators and will increasingly act to exclude of the latter from access to Western European and North American markets, and that any local environmental gains produced may be of relatively minor significance.
► Transfers allowed households to increase food expenditures and improve dietary diversity. ► Cash recipients smoothed food consumption and reduced hunger during the rainy season. ► A variety of food is available in local markets. Transfers link poor households to markets. ► Transfers increase both the likelihood of having and the quantity of food stores. ► Policymakers are optimistic about the cash transfer, but the sustainability of the SCTS is unclear. The Malawi Social Cash Transfer Scheme (SCTS) was launched in 2006 to improve food security by directly providing cash transfers to the country’s most destitute households. Although government-implemented cash transfer schemes have gained popularity throughout Latin America, these schemes are just emerging in Africa. While where there is evidence of the beneficial impact of cash transfers on food security from Latin American countries, there is a dearth of evidence from resource poor countries in Africa. In order to fill this gap, we conducted a longitudinal, randomized community control study of the pilot SCTS in Mchinji, Malawi from March 2007 to April 2008. In this study, we describe the impact of approximately US$14 per month on food security among recipient households compared to control households using indicators of food consumption and expenditures and dietary diversity. We present compelling evidence, whereby each of the tested outcomes yields large effect sizes that are highly statistically significant, demonstrating a sizeable impact of cash transfers on food security and food diversity in rural Malawi. The SCTS appears to be an effective tool within the National Social Welfare Policy for improving food security in the country’s destitute households.
► Alternate wetting and drying reduces famers’ hours of irrigation use by about 38%. ► Alternate wetting and drying does not reduce yields and profits of rice farmers. ► Panel data is needed to better control for selection problems in future analysis. This article evaluates the impacts of a controlled irrigation technique in rice production called alternate wetting and drying (AWD). Propensity score matching (PSM) and regression-based approaches applied to farm-level survey data are used to achieve the objective of the study. The PSM and regression-based approach accounts for the potential bias due to selection problems from observable variables. Results of the impact analysis using both empirical approaches indicate that AWD, particularly the “Safe AWD” variant, reduces the hours of irrigation use (by about 38%), without a statistically significant reduction in yields and profits. This reduction in irrigation time translates to corresponding savings in the amount of irrigation water and pumping energy used. However, further analysis of the impact estimates suggests that the potential magnitude of the selection bias based on variables may still be able to eliminate the measured impact from the PSM and regression-based techniques that only control for selection based on variables. Hence, the current impact results have to be interpreted with caution and further data collection is needed to construct a panel data that would allow one to account for selection problems due to unobservable variables and, consequently, better estimate the AWD impact.