Biodiversity For Food Security
by Dr. Deryck Pattron
Why Biodiversity? Biodiversity refers to the multiplicity of plants and animals in a biological community and the many ecological niches that they may occupy. Biodiversity is a fundamental principle of ecology. Diversity in animals and plants species leads to greater stability of the ecosystem. The ecosystem functions more efficiently with different species occupying more niches and extracting full benefit from energy and nutrient availability. This in turn facilitates greater adaptability in the face of environmental challenges. Ecological niches occupied by different species may partly overlap and allow substitutions if one or more are lost.
Biological diversity is fundamental to agriculture and food production. People rely on the variety of food, shelter and goods for their livelihood. Yet, humans put increasing pressure on species and their environments. As a result, many plants and animals are at risk, as well as essential natural processes such as pollination, photosynthesis and the regeneration of soils by microorganisms.
In order to feed a growing population, agriculture must provide more food at an acceptable rate of production. It will also be essential to increase its resilience by protecting a wide array of life forms with unique genetic characteristics, such as plants that survive drought or livestock that reproduce in harsh conditions. Sustainable agricultural practices can both feed people and protect the oceans, forests, prairies and other ecosystems that harbor biological activity.
Global efforts have so far been insufficient to reach the World Food Summit and related Millennium Development goal of reducing the number of hungry by half by 2015. Adequate food is a basic necessity of life, a prerequisite for growth and healthy development. Yet hunger and malnutrition continue to affect the lives of hundreds of millions of people every year in all parts of the world. Some of the possible reasons for the declining food resources that increase the prevalence of hunger and malnutrition and the necessary corrective actions are discussed in relation to the biodiversity concept.
Causes Of Declining World Food Resources • The growth rates of arable land and irrigated areas have been consistently declining almost everywhere since the 1960s. There was a corresponding decline, especially in the 1980s in all major areas, in both developed and developing counties. Major soil-related problems prevented the expansion of arable land in the tropics and also water quality. Existing technology does not provide sustainable solutions to some of these problems.
• Land and water resources are currently losing productivity from deforestation, overgrazing, salinity, acidification and waterlogging of arable land because of mismanagement and misuse of technology. New farming systems will have to be developed to sustain the productivity of land and water resources and reverse degradation. Particular problem areas include finding alternatives to traditional slash-and-burn techniques of maintaining soil fertility in the humid tropics, integration of crop and ruminant livestock production and substitution of intensive irrigated rice monoculture by a rice-maze wet-and-dry season cropping system.
• Growth rates of yield of all major cereals have declined overall in most developing and developed regions during the 1980s and fertilizer growth has also declined. Previous worldwide yields of crops have largely been due to adoption of improved varieties along with chemical fertilizers and pesticides. But, this approach is short lived because of serious environment consequences. Promising new approaches are unlikely to eliminate the need for fertilizers and pesticides, but measures must be put in place to improve the efficiency with which these inputs are used.
Possible Remedies To Ensure Sustainable Food Production Using Biodiversity • Adopt, maintain and follow technological advancements for sustained agricultural growth. New varieties of plants and agricultural methods will have to be developed using biotechnology that are appropriate for agroclimatic conditions where the potential for growth exists. To raise yields, not only technology but also infrastructure research and extensions services. Strategies for new technology should not be imposed on farmers, but through effective communication, training and research should be phased in with the help of competent agricultural extension services. These measures should form part of an integral biotechnical approach that provides appropriate cultivars, plant nutrients and pests management.
• Control major physical constraints on crop yield and production. (i) Soil acidity affects large areas of mainly rainfed land in developed and developing regions, imposing serious limitations on yields, particularly in parts of Africa and South America. Research strategies on possible remedies have suggested the use of lime, organic manure and adjustment in fertilizer use to neutralize acidity and increase soil fertility. (ii) Irrigation expansion can increase the area under multiple cropping and can generate growth in yield. Factors that lead to significant increase impact on production include optimizing the irrigation potential of land, improving water conservation and diverting investments to irrigation. Water harvesting is an important method for collecting runoff water for supplementation irrigation which if used can increase soil fertility and increase yield. (iii) Fertilizer use can be increased in non-Green Revolution areas to increase yields. Fertilizers provide the necessary minerals and organic elements necessary for growth. Soil fertility is enhanced by burning vegetation and by using animal manure.
• Salinity decreases soil fertility and reduces crop yields. Improving or implementing irrigation systems to improve water distribution, water-use efficiency, reduce seepage, prevent waterlogging and micronutrient problems and remove and dispose of drainage water efficiently to avoid local salinity and off-site externalities.
• Reduce degradation of soils. Maintaining soils cover and improving organic matter content are considered to be the most effective in preventing runoff and erosion, as well as increasing soil moisture and fertility, with potential yield increases of 50 to 100 %. Measures designed to reduce degradation of soils include planting cover crops, green manuring and stubble mulching. Minimum tillage should be practiced to reduce the number of cultivation operations, cut costs, avoid excessive soil compaction and maintain residues on soil throughout the year.
• Agricultural intensification. Crop intensities are currently low in many countries in both rainfed and irrigated land. The exact reason(s) for this is unknown. Most intensive land use can be achieved by multiple cropping of annual crops. But, intensive cropping normally involves greater use of chemicals and mechanical technologies. There is greater demand for well-trained advisory services. (i) The integration of livestock into farming systems may improve crop intensity. Inadequacy of pasture to meet current demand is clear from the increasing use of supplementary feed for ruminants in many countries. Poor nutrition rather than poor breeding is the first constraint to increasing productivity of most ruminants in developing countries and this is linked to susceptible to diseases and parasites. Productivity of both pastures and ruminants could be increased by rearing young animals on pastures and then fattening them on arable farms in the dry season when pastures are unproductive and susceptible to damage from overgrazing. The range-reared stock could be fattened to greater weights and the land would benefit from their manure. (ii) Feed supplies may be improved on both natural pastures and in farming systems. Phosphate application and rotation grazing may increase natural pasture productivity, while the productivity of farming systems may be increased by incorpororation of leguminous forages or temporary pastures into crop rotations.
• On-farm technology for increasing yield of key crops. The adoption of the Green Revolution concept by developed and developing countries have led to the use of agricultural technology based on new cultivars with a high grain-to-straw ratio, the use of chemicals to supply plant nutrients and to control pest, disease and weeds and to use mechanization to eliminate drudgery and facilitate more timely and efficient cultivation, seeding and harvesting.
• Maintaining healthy plants. Biotic stress from insects, fungi, bacteria, viruses and weed take a heavy toll on plants during growth and storage. Chemical pest control reduces predators, but reliance on pesticide is quite costly. The application of pesticides can affect on-farm health and social costs of environmental externalities affecting soils, microorganisms water supplies.
• Changes in cultural practices. (i) Adjusting cultivation practices. (ii) Planting methods and planting or harvesting dates. (iii) Varying plant population and density. (iv) Managing nitrogen fertilizer use to discourage pest buildup. (v) Develop crop rotation to avoid monoculture.
• Use of biotechnologies to increase global food production. (i) Embryo transfer. (ii) Biological nitrogen fixation collection. (iii) Collection, selection, production of appropriate strains of bacteria. (iv) Plant tissue cultures. (v) Plant protoplast fusion. (vi) Monoclonal antibody production. (vii) Recombinant DNA diagnosis of plants and animals diseases. (viii) Genetic engineering of animals and plants. (ix) Development of vaccines. (x) Biological agents to control plant pests and diseases.
• Develop appropriate legislation for the conservation of natural resources including fisheries and forests.
• Develop proper management strategies that would reduce production costs.
• Improve access to land, water and other productive resources.
• Increase investment in agriculture.
Biodiversity alone cannot end hunger and undernourishment. Mobilization of Governments, the public and private sectors, the civil society, the international communities and the pooling of collective and individual resources are all needed if people are to break out of the vicious inhumane circle of chronic hunger and undernourishment both locally and internationally.
References Mcwilliams, M. (2000). Food Experimental Perspectives. New Jersey: Prentice Hall. Pattron, D.D. (2004). Recent Research in Public Health. New York: Scientific Publishers. United Nations Population Division (1998a). World Population Prospectus. New York: The 1996 Revision. http://www.cdc.gov http://www.fao.org/biodiversity http://www.paho.org
About the Author
Dr. Deryck Pattron, Chaguanas, Trinidad, West Indies
Learn more about food security, biodiversity
Dr Deryck D. Pattron is a Public Health scientist and specialist in Management in the Ministry of Health, Trinidad.