Achieving Food and Nutrition Security: The Role of Agroecology
Agroecology is defined as the application of ecological principles and concepts to the design and management of sustainable agricultural agroecosystems (Altieri 2005). Agroecosystem forms the basic unit on which agroecological principles are applied.
The population of the world has increased in recent years and is projected to reach between 9.6 billion in 2050 and 12.3 billion by 2100 (Gerland et al. 2014). The population of the world is expected to continue increasing for the rest of the century, with at least a 3.5-fold increase in the population of Africa. The population of Asia (mostly South Asia) and Africa (mostly sub-Saharan Africa) are expected to record a great share of the projected increase in population (Lichtfouse et al. 2009). The increase in population would definitely be associated with an increase in demand for food, energy, and other natural resources. Food security would therefore be mostly threatened in the regions where the greatest population increases are projected. In an effort to meet this growing need, most developed countries have adopted intensive form of agriculture that relies heavily on external inputs such as pesticide and fertilizer application for soil improvement and technologies including the use of machinery for land preparation and harvesting. This has caused a decline in the quality of natural resource base associated with agriculture (Altieri 2005). Inappropriate agricultural practices have led to pollution of soil, water, and air and loss of biodiversity and the provision of ecosystem services (Duru and Therond 2015). In the developing world, an extensive form of agriculture notably shifting cultivation has been practiced, which was sustainable in the past due to low population growth. Shifting cultivation, though adapted to the physical environments of some countries especially in West Africa and elsewhere in the tropics, is increasingly becoming unsustainable with increasing population growth. It also has led to decreased ecological regulation of water quantity, air and water quality, climate, erosion, and pests and diseases (Kremen and Miles 2012; Zhang et al. 2007). In most parts of the world, agricultural lands are producing below their capacity (e.g., van Ittersum et al. 2013). Though many developed regions have experienced on average high yield of major food and industrial crops over the years, productivity has been lowest in the poorest regions of the world where food is most needed (Chauvin et al. 2012).
Biodiversity and the ecosystem services it supports are crucial for achieving sustainable agriculture. Agriculture, in particular, relies on a wide range of ecosystem services including pollination, biological pest control, maintenance of soil structure and fertility, nutrient cycling, and watershed control (Gomiero 2016; Power 2010). Many traditional agricultural systems and nearby landscapes especially in Africa harbor a significant amount of the world’s wild biodiversity, which serves as alternative sources of food and income for poor farmers. Often these systems help to preserve genotypes of species with unique and desirable traits that have been found suitable over decades (Johns et al. 2013). Agriculture, biodiversity, and ecosystems therefore are highly interconnected in their impacts and challenges. Decreasing forest cover, degraded ecosystem services, loss of biodiversity associated with oversimplification of agricultural systems, and climate change are a few of the challenges that need to be addressed if food production systems are going to be sustainable (Landis 2017).
The major challenge therefore is to increase agricultural yield while ensuring environmental sustainability with a focus on conserving soil, biodiversity, and ecosystem services it provides. Development of framework, concepts, and strategies to balance agricultural productivity with the needs of ecosystems and biodiversity to ensure that they are all able to deliver their services in a holistic and sustainable manner is what needs to be the new focus (Pretty 2003, 2008; Holt et al. 2016). Agroecology has been put forward as a science, a set of practices, and a movement that is likely to provide solutions to many of the problems in the agricultural and food production systems and its subsequent effects on poverty, food, and nutrition security.
Agroecology has evolved over the years and is perceived differently by diverse schools of thought. The use of the terminology in science dates back to the 1930s. It was considered a farming practice in the 1970s and a social movement in the 1980s (Silici 2014; Wezel et al. 2009). Since the year 2000 the definition had been broadened to include food systems instead of agricultural systems (Wezel et al. 2009). It is considered as a science, as a set of agricultural practices, and as a movement (Gliessman 2006; Migliorini and Wezel 2017). As a science, its emphasis is on the study of the interaction of the biotic and abiotic components of agroecosystems. There is an ongoing debate among scientists if agroecology is entirely a new discipline or a discipline that integrates other well-established disciplines. Other authors have indicated that agroecology is an integrative discipline that encompasses elements of agronomy, ecology, sociology, and economics (Dalgaard et al. 2003). As a set of practices, it promotes sustainable farming systems that optimize and stabilize yield. As a practice it includes a number of already existing methods of agriculture, e.g., no-tillage, minimum tillage, conservation tillage, organic agriculture, eco-agriculture, evergreen agriculture, conservation agriculture, and organic farming, each focusing on a specific feature of agroecology (Hainzelin 2014). As a social movement, it promotes food sovereignty and multifunctional roles of agriculture systems (Kremen et al. 2012; Silici 2014). As a result of the different meanings, the usage, and interpretations of the terminology in different regions (e.g., the USA, Europe, and Latin America) as well as from the point of view of different authors, it becomes necessary to properly define the perspective from which the terminology is discussed. According to Hainzelin (2014), the concepts and the methods of agroecology as a science are still under development and therefore create a conceptual space that provides an opportunity to evaluate agricultural sustainability using strong interactions between science and society, with a suite of concepts, questions, and tools. The seeming lack of consensus on the definition or what agroecology really is also offers an opportunity for continuous debates that generate new ideas and concepts. In this paper the focus is on agroecology as a practice, the main principles underlying its application, benefits and challenges, and how agroecology can contribute to sustainable agriculture, food and nutrition security, and ending hunger as contained in the Sustainable Development Goal 2.
Core Principles of Agroecology
Generally, agroecology does not provide specific recipes, technical packages, standards, or prescriptions but rely on some basic principles which include recycling, efficiency, diversity, regulation, and synergies (Gliessman 2007; Tittonell 2014). The main aim of an agroecological design is to integrate different components to improve biological efficiency, preserve biodiversity, and maintain the productivity and self-regulating capacity of the agroecosystem rather than focusing on individual species of trees, varieties of crops, and breeds of animals (Altieri 2005; de Schutter 2010). The system is expected to mimic the structure and functions of a local natural ecosystem where ecological interactions and synergies between biological components provide the mechanisms for the systems to sponsor their own soil fertility, productivity, and crop protection (Altieri and Rosset 1996). Agroecology focuses on the use of local resources. As a result, its application would depend on a given social-ecological context since there are differences in different localities in terms of natural resources and climatic factors such as rainfall. In a recent publication, Silici (2014) grouped agroecological principles into three main categories, namely, the planning phase, resource use, and field and landscape management. A number of other principles have been outlined by other authors (e.g., Altieri 2005) some of which overlap with the principles outlined in the work of Silici (2014).
In planning the design and management of an agroecosystem, the principle is to use a holistic approach. The agroecosystem is regarded as one entity, and the health of the whole system is deemed more important than the productivity of a single variety of crop or a breed of an animal. Thus, steps are taken to integrate the farming system with the productive potential and physical limit of the surrounding landscape (Silici 2014).
Many ecological principles are applied to the design of an agroecosystem. Notable among them are the recycling and optimization of nutrients and energy on the farms (Silici 2014; Altieri 2005). Particularly, biomass recycling is improved with the aim of enhancing the decomposition of organic matter and nutrient cycling over time. Efficient cycling of nutrients in the agroecosystem can be assessed using metrics that include reduction of runoff and erosion, reduction in leaching, improved soil carbon, and improved soil water holding capacity (Tully and Ryals 2017).
Another principle is the conservation and regeneration of soil water resources and agrobiodiversity to minimize loss of energy, water, and genetic resources. Across the globe soils are being managed to provide multiple benefits especially in the era of climate change to meet the ever-increasing food demand, filter air, purify water, and store carbon (C) to offset the anthropogenic emissions of CO2 (Blanco-Canqui and Lal 2010). Consequently, soil conservation measures such as zero tillage or no-tillage, minimum tillage, and conservation tillage, which are all features of agroecology, have emerged as strategies in modern farming that adequately protect the soil from erosion and at the same time provide solid economic returns and enhanced environmental benefits. No-tillage system has been found to increase soil microbial biomass, soil carbon, and nitrogen contents than conventional tillage methods (Mathew et al. 2012).
Agroecology avoids or minimizes the use of agrochemicals such as inorganic fertilizers and pesticides that have severe effects on environment and which often lead to immediate and long-term effects (Bhandari 2014). The use of locally available resources such as manure from livestock will improve the nutrient level of the soil within the agricultural systems. Additionally, avoiding the use of technologies that rely on fossil energy will contribute to reduction in greenhouse gas emissions. Energy from renewable sources such as biomass can be used to fuel farm machinery such as tractors and harvesters.
Field and Landscape Management
Implementing sustainable management practices on the farm and the entire landscape promotes the needed biological interaction and synergies among the various components of the agrobiodiversity. This would promote ecological processes and services rather than production of individual species of trees, varieties of crops, and breeds of animals. In addition, there should be a focus on efforts to prevent infestation of pests and diseases instead of control.
Maintenance of a high level of biodiversity and agrobiodiversity at both field and landscape level is key to achieving sustainability. The internal regulation functions of an agroecosystem hinge on the level of plant and animal diversity (Altieri 1999). This is because a number of renewal processes and services such as recycling of nutrients, regulation of microclimate and local hydrological processes, and suppression of undesirable organisms are biological and in part facilitated by biodiversity and therefore their persistence is critical for continued maintenance of the biological integrity and diversity of agroecosystems (Altieri 1999). Diversity is key in an agroecosystem for a number of reasons which include the following: (1) increasing diversity comes with the opportunities for beneficial interactions among coexistent species and synergies among agrobiodiversity components thus resulting in the promotion of key ecological processes and services and improved sustainability of agroecosystems; (2) a greater diversity also promotes better resource use efficiency; and (3) there is increased resistance to herbivores brought about by greater abundance of natural enemies of insect pests that keep the population of herbivores in check. Diversity in crops especially in marginal areas reduces risk for farmers as income from other successful crops compensates for crops that fail (Gliessman 1998). One way to ensure diversity and adaptation to changing environmental condition is the use of locally adapted varieties of crops and breeds of livestock instead of exotic species.
Benefits and Challenges of Agroecology to Food and Nutrition Security
Agroecology has evolved as a practical approach that has the potential to transform the different forms of agriculture of the world into more sustainable forms and systems. It is expected to have a positive impact on food and nutrition security and contribute to ending hunger as has been targeted by the global community (Lappe et al. 2013). Several authors (Altieri and Toledo 2011; Holt-Gimenez and Altieri 2013; Kremen et al. 2012) and international organizations have examined the benefits of agroecology. Some institutions have arrived at various conclusions through the assessment of some agricultural practices such as agroforestry, integrated pest management, no-tillage, and organic farming, which are integral to agroecology. Because agroecology depends heavily on locally available natural resources such as nature and richness of the soil, available biodiversity, the environment, and climate, particularly amount and distribution of rainfall, the expected benefits would differ from location to location (FAO 2015). Key benefits that were outlined by Silici (2014) include environmental sustainability, climate resilience, high overall productivity, and optimization of yields, livelihoods, food and nutrition security, and sovereignty.
Environmental Sustainability and Climate Resilience
Resilience of agroecosystems to environmental perturbations has become a concern in the global community. Reported increased variability in climatic factors such as frequency and intensity of rainfall and drought due to climate change has had negative impacts on the natural environment. In agricultural systems where principles of agroecology have been adopted and applied, increased resilience to climatic changes and resistance to pests have been reported (Silici 2014). A high degree of crop and animal diversification expected to be associated with agricultural systems applying agroecological principles usually reduces risk and provides options for future adaptation to changes in climate (Altieri 2004). Increase in above- and belowground biomass through diversity in crops also provides several other environmental advantages such as climate change mitigation through carbon sequestration by both the soil and plants. Minimal use or nonuse of agrochemicals and less use of fossil fuel-based machinery reduce emissions of some greenhouse gases, which ensure environmental stability. These benefits are said to be more pronounced in marginal environments and under adverse climatic conditions, where agroecological practices are often more productive than conventional farming. A number of studies have been carried out to compare forms of farming that integrate aspects of agroecological practices with conventional agriculture. In most cases the agroecological system shows better resilience to environmental and social perturbations than the conventional type of farming mainly due to diversification in the former system (Perfecto and Vandermeer 2010). Nicholls and Altieri (2017) reviewed a number of such studies. A study conducted in the hillsides of Central America to assess the response of crops after Hurricane Mitch showed that there was less damage on farms where diversification practices such as cover crops, intercropping, and agroforestry were applied compared with neighboring farms where conventional methods (monoculture) were implemented (Nicholls and Altieri 2017). Similar results have been reported for studies conducted in other countries. Nicholls and Altieri (2017) reported results from a survey of more than 1800 “sustainable” and “conventional” farms in Nicaragua, Honduras, and Guatemala. According to their report the “sustainable systems” showed a 20–40% more topsoil, greater moisture content, and less erosion and also experienced smaller economic losses than the conventional farms. Additionally, data from 94 experimental studies showed a longer return interval for crop failure in response to disaster (i.e., one in 36 years) for plots where sorghum was intercropped with pigeon pea compared with a shorter return interval for crop failure (one in 8 years) when only sorghum crop was grown. This indicates that intercropping shows greater yield stability and less decline in productivity in response to the effects of adverse weather conditions (Nicholls and Altieri 2017). Similar patterns were reported in other case studies in Bolivia, Kenya, and China in which local crop diversity was critical in enabling farmers to adapt to worsening pests, drought, and increased climate variability (Nicholls and Altieri 2017).
Better Overall Productivity and Optimization of Yields
One of the major objectives of agroecology is to enhance the multifunctional role of agricultural systems rather than increase in the yield of individual varieties of crops. Compared to input-intensive conventional agricultural systems, many agroecological systems do not produce crops with higher yield (Silici 2014; Epule and Bryant 2016). However, the total agricultural output is larger than conventional system because farmers rely on a diversified pool of crops and livestock. Furthermore, greater resilience to extreme climatic events and resistance to pests and other environmental stresses make yields more stable over time (Holt-Gimenez and Altieri 2012). The overall productivity of agroecological farming system would be increased and optimized when the provision of other ecosystem services is taken into consideration.
Livelihoods, Food and Nutrition Security, and Food Sovereignty
Agricultural lands now cover over 40% of the global land surface area and constitute the ecosystem at the center of human livelihoods (Wood and DeClerck 2015). Especially in the developing world, majority of the inhabitants depend on smallholder farms for their livelihood and food needs. About 84% of the world’s farms are small (≤2 ha) (Lowder et al. 2014) and contribute to world’s food production. According to former UN Special Rapporteur on the Right to Food – Olivier de Schutter – agroecology is a farming approach which has been found to show strong conceptual connections with the right to food as well as food security. Achieving food security in its totality is a daunting global challenge as it is a problem for both the developed and developing countries though in different magnitude. There are four dimensions to food and nutrition security, namely, the physical availability, economic and physical access to food, utilization of food, and stability of the mentioned dimensions over time. The physical availability indicates the supply aspect of food which is determined by level of food production, stock levels, and net trade (Bokeloh 2005). Access to food is influenced by physical, social, and policy environments, which determine how effectively households are able to use their resources to meet their food security objectives.
Utilization especially at the individual level refers to the ability of the human body to take food and convert it into energy that is used for either daily activities or stored. In addition to having adequate diet, a healthy physical environment including safe drinking water and proper health care, food preparation, and storage processes are required to ensure sufficient energy and nutrient intake. To achieve total food and nutrition security, stability of the three dimensions of food and nutrition security over time is important. Periodic inadequate access to food which increases the risk of deterioration in nutritional needs can render farm families or households food and nutrition insecure. Other factors such as adverse weather conditions, political instability, or economic factors (unemployment, rising food prices) may have an impact on the food and nutrition security status of households or farm families (Haile 2005). Agroecology provides a system that potentially helps in satisfying all the four dimensions of food security (Gliessman and Tittonell 2015). Application of agroecological practices to most agricultural lands contributes to food security by promoting diversity in production (and thereby in diet) and by enhancing the nutritional value of crops. In addition, agroecosystems with high biodiversity are also generally more resilient to environmental perturbations and thus enhance secure food supply (Frison et al. 2011; Wood and DeClerk 2015).
Nutrition security has three determinants, namely, access to adequate food, care and feeding practices, and sanitation (Wüstefeld 2013). Agroecology can improve local food production and improve access to food as well as provide right dietary preference which promotes nutritional security within an environment that is stable and free from poor sanitation and diseases. The provision of a wide range of ecosystem services such as air and water purification on farms implementing agroecological principles also enhances the well-being of farmers.
The application of agroecological principles in farming places the farmer and the household at the center of decision-making concerning food production and thus contributes to food sovereignty. Due to the reliance of locally sourced or self-produced inputs, farmers are spared the trouble of having to depend on expensive and often hard to access products and thus become less vulnerable to price fluctuation.
Challenges to the Adoption of Agroecology
Implementation of agroecological principles requires knowledge and capacity in biological interaction of plants and animals on a farm field and the entire landscape. This may pose a challenge to majority of smallholder farmers who have little formal education in spite of the skills that they have acquired over the years employing somewhat sustainable indigenous methods of farming. Insecure land tenure systems and lack of or inadequate access to natural resources can also inhibit the uptake of agroecology by discouraging farmers from adopting practices such as agroforestry and soil conservation practices that require investment in land and other assets. Extension officers in some developing countries lack the requisite skills and knowledge to offer extension services to farmers to facilitate the adoption of agroecological principles. Many agroecological practices that have been implemented on small scale are location specific. There could be challenges in scaling up similar practices in other regions and thus inhibit their adoption.
There is a lack of policy especially in most developing countries to promote agroecology and support its implementation on smallholder farms. Government efforts in many developing countries that seek to develop and modernize agriculture are focused on increased yield of crops and not necessarily on the overall health of agroecosystems and the provision of environmental services such as carbon sequestration and pollination. There are no special loan facilities that help famers to pay for the initial labor and other inputs that are required for applying agroecological practices to farms. Additionally, food produced from farms applying agroecological principles does not attract a premium (to pay for environmental services) in most countries. Income from such premium payment could be useful in offsetting some of the initial investments making the production profitable in the short term.
Current agricultural education in most countries does not yet focus sufficiently on the functioning of cultivated ecosystems, which is the central focus of agroecological practice. In cases where attempts have been made to incorporate agroecosystem functioning in such training courses, farmers’ knowledge and know-how have not been sufficiently harnessed (Wezel et al. 2018). There is inadequate investment in agroecological research, which affects the scope. For instance, agronomic research focuses less on agroecological solutions therefore affecting the transfer of such solutions to farmers.
There has to be a paradigm shift in the way agriculturalists are taught to conduct on-farm research and the way extension workers are trained to reflect the complex nature of agroecosystem taking into account agroecological principles. The focus on new studies should rely on multidimensional analyses that measure not just crop yields but also other outputs, such as feed available for livestock, mulching crops, and provision of ecosystem services. Cost-benefit analysis of complete or partial implementation of agroecological principles should be conducted. New matrices for assessing productivity of farms that take into account ecosystem services should be developed. Based on results of the cost-benefit analysis, incentive or subsidy packages can be implemented especially in developing countries where food insecurity is on the rise due to rapid growth in population and the degradation of most agricultural lands. Farmers should be encouraged to gradually shift from the conventional methods of farming to sustainable design using agroecological principles (Kremen and Miles 2012). The right investment in agroecological research to improve organic management systems could significantly reduce or remove the yield gap found between organic and conventional farming for some crops (Ponisio et al. 2015).
Other examples of specific actions that should be taken to make it easier for farmers to adopt agroecological principles and practices include policy interventions, innovative and transformative processes, postharvest handling, diversification, and integration.
There is the need to focus support on interventions that make a significant contribution to farm efficiency, in particular, extension services and access to markets (Kansiime et al. 2018). An example of policy intervention is to transform the current outlook and delivery of agricultural extension services as indicated by Aflakpui (2007). Transforming the outlook and delivery of extension services would not only help enhance the capacity and empower smallholder farmers to demand extension services but to also apply improved technologies in an informed way. Enhancing the role of smallholder farmers may be done in a variety of ways such as (a) empowering women farmers through improved advocacy for the rights of women to own land in countries where land tenure is a challenge, as well as livestock and other assets for production and processing of farm produce, and (b) improved education of farmers especially women with a variety of key messages on nutrition education and improved household nutrition.
Another example of policy intervention is to focus on pro-poor and social protection strategies. Pro-poor growth strategies, which ensure that the weakest participate in the benefits of market integration and investment in agriculture, would improve their income and investment opportunities in rural areas. Combining social protection with pro-poor growth will help meet the challenge of ending hunger and addressing the triple burden of malnutrition and extreme poverty through healthier diets. Building resilience to protracted crises, disasters, and conflicts and preventing conflicts by promoting inclusive and equitable global development would contribute immensely to eliminate permanently hunger, malnutrition, and extreme poverty (FAO et al. 2017).
A policy on crop insurance is another intervention that could enhance the capacity of farmers to intensify agriculture. The lack of insurance mechanisms in agricultural production, for instance, has been reported to hamper investment in agricultural assets, such as machinery needed for conservation or minimum tillage, as variable weather conditions render these investments too risky to be affordable. Adiku et al. (2013), in a study with Climate Change, Agriculture and Food Security (CCAFS) project, demonstrated the feasibility of extending a microscale crop insurance product directly to farmers. The farmer-tailored product was for maize and sold at a premium of US$5.00 per acre (approx. 0.5 ha). In a pilot project at Lawra (Upper West Region of Ghana), an initial number of 15 farmers and extension workers were trained on crop insurance, but as many as 80 farmers had purchased the crop insurance product for the following season.
Innovative and Transformative Processes
The Food and Agriculture Organization (FAO 2017) has indicated that sustainable food and agricultural production cannot be delivered by high-input, resource-intensive farming systems. This is because it is this system which has caused massive deforestation, water scarcities, soil depletion, and high levels of greenhouse gas emissions. The FAO (2017) asserts that innovative systems that protect and enhance the natural resource base, while increasing productivity, are the ways to go. Transformative processes that encourage holistic approaches such as agroecology, agroforestry, climate-smart agriculture, and conservation agriculture (Aflakpui et al. 1993, 2007; Marks et al. 2009) which also build upon indigenous and traditional technical knowledge are promising and should be pursued.
Improved postharvest handling through optimal harvesting, storage, and value addition will reduce losses after harvest. Proper handling will preserve valuable nutrients especially the micronutrients. Diversifying crop species and breeds of animals as a means of encouraging and enhancing biodiversity will help fight the scourge of malnutrition and undernutrition. Encouraging integrated farming systems where crops and livestock coexist independently but interact to create synergy with recycling allowing the maximum use of available resources will surely enhance sustainable production.
The use of mobile telephony to make farmers have time-bound access to extension services and updated information on opportunities, state-of-the-art practices, and markets to sell their produce is one of the innovative and transformative ways that would enhance incomes of households and farm families. Access to information is vital for consumers and farmers as access is an important aspect of food and nutrition security.
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