Sustainable Agriculture and Food Security1 PDF

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The highlights sustainable agriculture as the main solution to the global food security, and draws the connections between sustainable agriculture an food security....

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LECTURE NOTES Prof. R. O. Mosi SUSTAINABLE AGRICULTURE

What is Sustainable Agriculture? Sustainable agriculture has assumed global and, to some extent, traditional importance because of the adverse social and environmental effects of modern agriculture. Modern agriculture is characterized by:   

use of high yielding crop varieties and livestock breeds; high external inputs; and Non-renewable energy.

Modernization of agriculture has been adopted as a means of development and transformation of rural communities and nation’s prosperity. However, the excitement about these potential benefits were lost because of the following factors:   

regional imbalances; social inequity in development; and rapid environmental degradation.

Massive and injudicious use of inorganic fertilizers and toxic pesticides and herbicides, besides large scale irrigation, has led to huge damage to ecosystem and, more importantly, the human and animal health. Pretty (1966) reported that such impacts include: 1. Contamination of water by pesticides, nitrates, and wastes, causing harm to human livestock and wildlife, and disruption of ecosystems; 2. Contamination of food and fodder by pesticide residues; 3. Damage to farm and natural resources by pesticides; 4. Contamination of atmosphere by ammonia, methane, etc.; 5. Ozone depletion, global warming and atmospheric pollution; 6. Overuse of natural resources causing depletion of ground water; 7. Replacement of adaptive traditional crop varieties and livestock breeds with less adaptive but high yielding varieties and breeds; and 8. Emergence of new hazards due to agrochemicals---during field sprays and working agromanufacturing industries. Imprudent and rampant use of chemical fertilizers has led to imbalance in soil nutrient status, thus depriving crops of essential nutrients. Furthermore, imprudent and rampant use of pesticides has resulted introduced pesticide residues in blood as well as mothers’ milk; exposed human and animals to deadly diseases; and threatened the existences of some organisms. 1

Realizing the catastrophic impact of pesticides, the famous American writer, Carl Rachel, in her famous book, “The Silent Spring”, has warned that human beings are an integral part of nature and any war against nature is the war against self. She further advocates that often the technological advancements become so antagonistic with the nature’s activities and system that it is wise to put it off. On their hand, the proponents of modern and exploitive agriculture still argue in their favour and advocate for their continuance for food security and prosperity. This debate is ongoing between modernists on the one hand, and environmentalists and conservationists on the other hand, over issues related to sustainable agriculture and food security. However, it should be noted that, while ensuring food security to the growing population is an important, global concern, conservation of natural resources and protection of environment to derive benefits sustainably are equally important. Consequently, vision and action towards balanced and sustainable agriculture have been recognized and accepted by agricultural scientists, policy makers and development agencies.

Concepts Philosophy of Sustainable Agriculture The word sustain has been derived from a Latin word root sustenere (sus meaning “from below”, and tenere meaning “to hold”) means to keep or maintain through long-term support or permanence. According to Jennings and Ikerd (1994), the concept of sustainability first came up during the energy crisis of the1970 in relation to the global supply of oil. At that time, the term was defined as “maintaining the present without compromising the future” In the context of agriculture, sustainability implies “satisfying the needs of the present generation in terms of food security, environmental and social quality, and prosperity without compromising the opportunity of the future generation for the same needs,” and it recognizes the nexus between agriculture, environment and people. Therefore, sustainable agriculture has three dimensions: social, economic and ecological. Sustainable agriculture has been defined by Food, Agriculture, Conservation and trade Act (FACTA, 1990) as ‘an integrated system of plant and animal production practices having a site specific application that, in the long term:     

Satisfy human food and fiber needs; Enhance environmental quality; Promote efficient use of renewable energy and resources; Sustain economic vitality of farm operations; and Enhance quality of life for farmers and society as a whole.

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Goals for Sustainable Agriculture A sustainable agriculture is any system of food or fiber production that systematically pursues the following goals: 1. Thorough incorporation of natural processes such as nutrient recycling, nitrogen fixation and pest-predator relationships into agricultural production processes. 2. A reduction in the use of off-farm, external and non-renewable inputs. 3. A more equitable access to productive resources and opportunities, and progress towards more socially just forms of agriculture. 4. Productive use of the biological potential of plant and animal genetic resources. 5. An increase in self-reliance among farmers and rural people. 6. Long term sustainability of the current production levels. 7. Profitable and efficient production with emphasis on integrated farm management, and conservation of the soil, water, energy and biological resources.

Dimensions and parameters of sustainable agriculture In order to practice sustainable agriculture, farmers must have a holistic understanding of what is required. Researchers have identified 12 major dimensions of sustainable agriculture covering: 1. Technologically appropriate 2. Economic feasibility 3. Economic viability 4. Environmental soundness 5. Temporal stability 6. Resource -use efficiency 7. Local adaptability 8. Social acceptability 9. Political tact 10. Administrative manageability 11. Cultural desirability 12. Equity and Productivity The main physical and biological features of sustainable agriculture include: 1. Diversity of agricultural genetic resources 2. Selection of crops and livestock that are adapted to a particular environment 3. Preference for farm generated resources rather than purchased materials 4. Efficient control of nutrient cycles to minimize nutrient losses 5. Livestock housed and grazed at low stocking density 6. Enhancement of storage of nutrients in the soil 7. Maintenance of protective cover on the soil 8. Rotation that includes deep rooted crops and control of weeds 9. Use of soluble inorganic fertilizers 10. Use of pesticides for crop protection only as a last resort 3

Guiding principles of sustainable agriculture CUESA (Center for Urban Education about Sustainable Agriculture), San Francisco (2005), envisages a healthy world fed by sustainable food systems. The guiding principles for sustainable agricultural production advocated then emphasized on environmentally sound, humane animal management, and economically viable and socially just technologies 

Environmentally sound Farmer’s activity create and sustain cultivated landscapes that are complex, diverse, and balanced biological systems. Producers use practices that conserve and restore resources.

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Humane Animal Management While being raised, animals should be allowed to engage in the natural behaviors that are important to their health and are harvested in ways that minimize stress to the animals the environment.

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Economically Viable Farmers operate within a framework of sound business planning and pursue integrated business planning and pursue integrated and proactive approaches to marketing and sales.

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Socially Just Farmers and their employees receive fair and reasonable compensation and work in safe and respectful environment.

Sustainable Agriculture: Pragmatic Roadmaps Transformation to sustainable agriculture cannot be an instant event. Farmers first need to have a connection about the potential of sustainable agriculture in meeting the ever growing demands for food, feed, fiber and fuel for the families and community at large. Currently, there is a global debate on whether food sufficiency could be achieved and maintained with sustainable agricultural practices or it will revert to subsistence level. There are, however, good evidence to prove that with sustainable agricultural practices not only the level of productivity could be sustained, but also the production could be replenished and rejuvenated. A realistic roadmap to sustainable agriculture requires integrated emphasis on adoption of resource-conserving technologies, participation of farmers and unions, partnerships and political support. A part from the above factors, value-orientation and perception of practitioners toward sustainable agriculture is of great importance. Sustainable agriculture must put emphasis on:      

Conservation and replenishment of natural resources (soil and water). Use of eco-friendly methods of pest management. Conservation of energy resources. Conservation of biodiversity. Recycling of organic waste. Location specific crops and breeds of livestock.

Main steps to sustainable agriculture: 4

1. 2. 3. 4. 5. 6.

Create and conserve healthy soil. Conserve water and protect its quality. Manage organic waste without pollution. Manage pests with minimum environmental impact. Select crops and livestock that are adapted to the prevailing environment. Promote biodiversity. 7. Increase profitability and reduce risk.

Shift in value-orientation and Perception of Practitioners and policy makers Values are guiding forces of human behaviours and are key to the evaluation of sustainable society. Consequently, in order to facilitate transformation to sustainable agriculture, it is imperative to start from the level of change in the value- orientation as well as the perception of individuals. Furthermore, in order to enhance sustainable agriculture, it is important to learn to live in harmony with the animals in order to co-exist with nature, wisdom, values and methods are closely integrated in traditional agricultural systems. Thus, farmers need to adopt some of the good indigenous knowledge and integrate them into the modern agricultural practices to achieve sustainability in the process. Documentation, validation, integration and scaling up of indigenous technologies and practices are necessary for standardization of sustainable agricultural practices.

Promotion of systems approach Farming must be viewed in a system perspective with sufficient attention to interrelatedness and interdependence of important components or elements of the whole systems. A rural farming system possesses five basic assets: natural capital; social capital; human capital; physical capital; and financial capital, all of which are transformed by processes, institutions and policies to deliver outcomes to farmers in form of deliverables for sustainability. Thus, sustainable agricultural system is one which accumulates and increases these bases overtime. On the other hand, a system which depletes its capital base is called an unsustainable system. For sustainability to prevail it is desired that activities are planned and implemented in a systematic perspective i.e. taking into account the impact and consequences of one activity on another related activities.

Adoption of resource- conserving technology and the impact The great desire for high productivity has led to great increases in food grain production and selfsufficiency in some developing countries such as India. Unfortunately this has been achieved at the greater social and environmental cost. In many developing countries, one of the most critical disadvantages has been the disappearance of integrated and mixed farming systems. This has been due to agricultural intensification that has led to high degree of specialization of crop cultivation and animal production systems. This has further led to the following adverse effects:     

over-reliance on external inputs; overexploitation of ground water; ecological pollution; degradation of land and water bodies; and health hazards.

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The damage to the production system can be greater because of the disconnect of farm crop and livestock enterprises which in traditional Systems, operate as integral component and help in rejuvenating the system. The principles of integrated farming are a key to sustainable agriculture and, therefore, a variety of technologies and practices for pest, nutrient, soil and water management are required for practicing sustainable agriculture.

Management of soil and water resources Sub-Saharan Africa (SSA) has diverse forms of soils, which presents varying land quality (capability). Most of the land areas are prone to soil related constraints, including draught, high temperatures and nutrient imbalance. This requires sustainable management practices for higher water use efficiency (WUE) and increasing crop yield sustainably. The status of water resources is also not encouraging. Of the total annual rainfall, high losses are incurred due to soil infiltration, run-off and evaporation, and the magnitudes of these losses vary according to the agro-ecological zones. Another greater concern is the low efficiency of water use for irrigation. It has also been observed with concern that per capita availability of fresh water resources in SSA is declining annually. Consequently, arid and semi-arid lands are likely face severe water shortages in the near future. In such situations, it is prudent to promote adoption of technologies and practices for soil and water conservation on farm.

Soil-water management The principles to be adopted for improved soil-water management should aim at:  increasing water infiltration with improved soil aggregation;  decreasing run-off with use of contours, ridges and vegetative hedges, and  reducing evaporation with the use of crop residues mulch.

Soil surface management The main aim in soil surface management are to increase soil water retention by largely reducing soil water evaporation. Technologies to achieve these include: deep tillage; conservation tillage, and mulch farming etc., while soil conservation practices should include: conservation tillage, contour farming, mulches and cover crops, silt traps and gully fields.

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