Food Security and Environmental Sustainability

Autoria: 
Juliana Santilli (founding member of ISA and Public Prosecutor for the Public Ministry in the Federal District).

It is the diversity of cultivated plants and domestic animals, and their capacity to adapt to adverse environmental conditions (climate, soil, vegetation, etc.) and the specific human needs, that ensures farmers the possibility of survival in many areas subject to environmental stresses. It is the cultivation of diverse species that protects the farmers, in many circumstances, from a total loss of the crop, in cases of plague, disease, prolonged drought, etc. With monocultures, with an extremely narrow genetic base, the contrary occurs: Plagues, disease, etc. hit the only cultivated species and completely destroy the crop.


Área desmatada  / Maurício Torres

Genetic uniformity creates enormous risks and uncertainties for agricultural cultivation, which becomes especially vulnerable. The situation of genetic vulnerability1 is characterized by one plant cultivated on a large scale being uniformly susceptible to plagues, diseases, or environmental stresses, due to its genetic constitution, thus creating risks of the total loss of the crop.  Even if a modern variety has been developed to be resistant to a determined pathogen2, any mutation of this pathogen, no matter how minor, could be sufficient to break such a resistance, making the entire crop vulnerable.

One of the most famous examples of the dangers presented by genetic uniformity was the “Great Famine” that occurred in Ireland, between 1845 and 1851, provoked by the generalized devastation of the potato plantations by a fungus (Phytophthora infestans).  Ninety percent of the population of Ireland depended on the potato as their main source of food. The fungus wiped out the potato plantations and famine killed 2 million Irishmen (25% of the population). In this period, 1.5 million Irishmen migrated to the United States, Australia, and New Zealand. Many died during the voyage or soon upon arrival, weakened by malnourishment3.

There are, however, more recent examples. In the 1970’s a plant disease caused by a fungus (Bipolaris maydis), known as “the Southern Corn Leaf Blight”, attacked the corn plantations of the American states (initially from the south and moving north, hitting Minnesota, Michigan, and Maine). Some states came to lose half of their crops. This also occurred in 1971 on a Soviet plantation growing the same variety of wheat, known as Besostaja, in an area of 40 million hectares, extending from Kuban to Ukraine. This particular variety presented high yields when cultivated in Kuban, where the temperatures were more pleasant. That year, the Ukraine suffered an extremely rigorous winter that devastated its plantations and led to the loss of 20 million tons of wheat, which corresponded to 30% to 40% of the crop. As pointed out by Cary Fowler and Pat Mooney4, in both cases the blame for the losses of the corn and wheat crops in the United States and Ukraine must not be attributed to the plague that infested the corn plantations or to the to the rigorous winter in the Ukraine, but rather to the genetic uniformity of the crops5. The crops would not have been so drastically devastated had diverse varieties been planted.

Agro-biodiversity is essential to food  and nutritional security, which consists of the realization of the right of everyone to the regular and permanent access to quality foods, in sufficient quantities, without compromising the access to other essential necessities, based on health-promoting nutritional practices that respect cultural diversity and that are environmentally, culturally, economically, and socially sustainable. This is the concept established by Article 3 of Law no. 11.346 of September 15, 2006, that creates the National System of Food and Nutritional Security, with the aim of ensuring the human right to food.

Agro-biodiversity is not only associated to the sustainable production of food, as it also has a fundamental role in the promotion of food quality. Diverse food  – balanced in proteins, vitamins, minerals, and other nutrients – is recommended by nutritionists and is a fundamental condition for good health. Only agro-biodiverse agricultural systems favor more nutritive and balanced diets. The reduction of agricultural diversity and the impoverishment of diets are directly related. Genetic erosion in the field affects not only the farmers, but the consumers as well.

The models of agricultural production have direct implications for food , for nutrition, and for human health. “Modern” agriculture and the cultivation of few agricultural species favor the standardization of food habits and the cultural devaluation of native species. In the Andes, for example, many plants traditionally employed in the diets of indigenous peoples and local farmers, such as quinoa (Chenopodium quinoa), amaranth (Amaranthus caudatus), chocho (Lupinus mutabilis), kanin (Chenopodium pallidicaule), virac (Arracacia xanthorrhiza) and yacón (Polymnia suochifolia), are being abandoned and substituted by imported species, such as spinach, cauliflower, and celery, whose cultivation requires much greater use of fertilizers, including chemical ones. In the tropical regions of the Americas plants such as purslane (Portulaca oleracea, also known as “black salad,” cultivated for making salads and of nutritional value nearly the same as spinach) and nasturtium (Tropaeolum majus) have been used, which were already very important to the local agricultural systems and the food security of rural populations6


Milho cultivado na comunidade remanescente quilombola de Bombas no município de Iporanga, São Paulo. 2010  / Anna Maria Andrade / ISA

Food centered on plants (fruits and vegetables) has been substituted by diets excessively caloric and high in fats, yet poor in vitamins, iron, and zinc. Foods are prepared with an ever-smaller number of species and varieties of plants, and the derivatives of corn and soy, for example, are present in the majority of industrialized food products. In order to have an idea, it is estimated that there exist between 250,000 and 420,000 species of superior plants, of which only thirty would correspond to 95% of human nutrition, and only seven of them (wheat, rice, corn, potato, manioc, sweet potato, and barley) make up 75% of this total.  More optimistic estimates point out, however, that 103 species would be responsible for 90% of the foods consumed on the planet, and not only the twenty or thirty species more commonly mentioned7.  By any means, human nourishment is based on a reduced number of vegetable species, which compromises health.

Poorly nutritive and balanced diet responds, in part, for the worldwide epidemic of chronic diseases, such as obesity, diabetes, cardiovascular diseases, and some forms of cancer. According to the World Health Organization (WHO), close to 177 million children throughout the world are threatened by diseases related to obesity, and the forecast is for 2.3 billion people over the age of 15 to be obese by 2015. Currently there are 1.5 billion obese people in the world, whereas 854 million are malnourished. In developing countries, fighting hunger and misery necessarily involves the adoption of more sustainable agricultural practices8.

Agriculture interacts with the environment in diverse ways that affect human health. The harmful effects of the indiscriminate use of agro-toxins are well-known. In extreme cases, they are capable of provoking genetic anomalies, tumors, and cancer.  The World Health Organization estimates that there occur throughout the world close to 3 million acute agro-toxic poisonings, with 220,000 deaths, every year, of which close to 70% occur in developing countries9.Besides the poisoning of rural workers in direct or indirect contact with these products, food contamination also hits the consumers. Because of their danger to human health and the environment, agro-toxins are subject to legal controls in many nations of the world, including Brazil10. Environmental changes produced by irrigation and by deforestation also favor the development of diseases such as malaria, schistosomiasis, etc.


Cesto de pimentas colhidas por uma mulher Pira-Tapuya, na sua roça dos arredores de São Gabriel da Cachoeira Ludivine Eloy/ISA 2004  / Ludivine Eloy/ISA

Agro-biodiversity is an essential component of sustainable agricultural systems. One of its principles is precisely the diversification of crops.  A greater number of species in a determined ecosystem, associated with other ecological factors, ensures greater stability and lesser necessity of external inputs, such as agro-toxins and nitrogenized fertilizers. Diversified agricultural systems also provide harvests of different crops in alternate seasons of the year. Crop failure, or the reduction in price of a determined culture, does not cause as much damage as in monoculture systems11.

The diversification of an agro-ecosystem can be undertaken in several ways, from the consortium of cultures, crop rotation (or “alternate harvests”), or even agro-forest systems, which are a system of forest management which looks to reconcile agricultural production and the maintenance of arboreal species. These systems promote the increase of organic material in the soil, decrease erosion, and preserve the diversity of species. When riparian forests are recovered, the decrease of water turbidity and an amplifying of water resources12.

Every agro-ecosystem, however, presents distinct characteristics, and demands specific solutions. Sustainable agriculture requires an understanding of the complex interactions among the different components of agricultural systems. Every agro-ecosystem should seek find adequate solutions to their environmental, economic, and social conditions. The specialization of productive systems and the genetic homogeneity that characterizes them not only provoke the decrease in the diversity of species and varieties as it also reduces species important to the balance of the agro-ecosystems, such as nitrogen-fixing bacteria, fungi that facilitate the absorption of nutrients, pollinators, seed dispersers, etc. They also compromise the resistance and resilience of the agro-ecosystems, making them more vulnerable to attack by plagues, droughts, climate change, and other risk factors13.

Find out more

SANTILLI, J. . Agrobiodiversidade e direitos dos agricultores. São Paulo: Peirópolis, 2009.

Notes and References

  1. NATIONAL ACADEMY OF SCIENCES. Genetic vulnerability of major crops. Washington: 1972.
  2. Patógeno é qualquer organismo capaz de causar doença infecciosa em plantas, ou seja, fungos, bactérias, vírus, nematoides e protozoários.
  3. Consultar: Woodham-Smith, Cecil. The great hunger: Ireland 1845-1849. Londres: Penguin Books, 1991; Bartoletti, Susan Campbell. Black potatoes: the story of the great Irish famine, 1845-1850. Michigan: Gale, 2002.
  4. FOWLWE, C. & MOONEY, P. Shattering: food, politics, and the loss of genetic diversity. Tucson: The University of Arizona Press, 1990. p. IX-XI.
  5. Ibid., p. XI.
  6. FAO. Plant Production and Protection Division. Seed and Plant Genetic Resources Service. “Seed policy and programmes in Latin America and the Caribbean.” In: Regional Technical Meeting on Seed Policy and Programmes in Latin America and the Caribbean, 20-24/3/2000, Merida, México. Proceedings. Roma: FAO, 2000. p. 32. (FAO Plant Production and Protection Paper, 164).
  7. WALTER, B. M. T et al. “Coleta de germoplasma vegetal: relevância e conceitos básicos.” In: WALTER, B. M. T. & CAVALCANTI, T. B. (eds.). Fundamentos para a coleta de germoplasma vegetal. Brasília: Embrapa, 2005a. p. 28-55.
  8. Consultar: Stern, Linda Jo et al. “Trabalhando agricultura e saúde conjuntamente.” Agriculturas: experiências em agroecologia. Rio de Janeiro: AS-PTA; Leusden: Ileia, v. 4, n. 4, p. 18-22, dez. 2007; Jhamtani, Hira & Jenny, Putu Anggia. “Superando a desnutrição com cultivos e sistemas alimentares locais.” Agriculturas: experiências em agroecologia. Rio de Janeiro: AS-PTA; Leusden: Ileia, v. 4, n. 4, p. 23-25, dez. 2007.
  9. Em 2008, o Brasil assumiu a liderança no consumo mundial de agrotóxicos. As vendas de agrotóxicos totalizaram 733,9 milhões de toneladas e movimentaram cerca de 7,1 bilhões de dólares, segundo o Sindicato Nacional da Indústria de Produtos para a Defesa Agrícola (Sindag). O Brasil superou o recorde dos Estados Unidos, maior produtor de alimentos do mundo, que consumiu 646 milhões de toneladas de agrotóxicos no mesmo período. Fonte: “No reino dos agrotóxicos: a Anvisa pode banir 13 pesticidas do Brasil, novo líder mundial de consumo”. CartaCapital, 20/05/2009, nº 546.
  10. A Lei nº 7.802/1989 regula a utilização, comercialização, transporte, armazenamento, importação e exportação de agrotóxicos.
  11. EHLERS, E. . “Agricultura sustentável.” In: Instituto Socioambiental. Almanaque Brasil Socioambiental: uma nova perspectiva para entender o país e melhorar nossa qualidade de vida. São Paulo: ISA, 2008. p. 414-419.
  12. BEZERRA, M. C. & VEIGA, J. E. (coords.). Agricultura sustentável. Brasília: MMA; Ibama; Consórcio MPEG, 2000. p. 75.
  13. EHLERS, op. cit., p. 419.