Sustainable agriculture includes a number of farming systems that are designed to allow food (or fiber) to be successfully produced indefinitely – sustainably.  It tries to reduce expensive and artificial inputs, such as petroleum-based fuels, fertilizers and pesticides.  It tries to reduce negative environmental and health effects, from soil degradation to water pollution to human sickness.

 Sustainable agricultural systems typically seek to improve soil conditions and to grow healthy plants and animals, which should then become healthful human food.  They basically try to work with nature, or natural processes, so as to maximize plant and animal production, while causing the least environmental disturbance or harm.  Thus by relying on the earth’s regenerative natural processes, sustainable agriculture can continue indefinitely.

For the most part, gardening is a type of sustainable agriculture on a small scale.  Organic agriculture is a type of sustainable agriculture in which the farmer uses no synthetic fertilizers, herbicides, pesticides or animal production stimulants, such as hormones and antibiotics

Conventional agriculture

Sustainable agriculture is often compared or contrasted to “conventional” agriculture, sometimes called “chemical-intensive” agriculture.  Those terms refer to various food and fiber producing methods that have mainly become widespread since the end of World War II (the mid-twentieth century) and which are now dominated by an interactive aggregation made up of agricultural colleges; fertilizer, seed and chemical product manufacturers and sellers; and commodity marketing and speculative enterprises.

Conventional agricultural systems are often promoted as being highly efficient at producing large quantities of food and fiber relatively cheaply.  They use the latest high-tech innovations, such as genetically modified crops that can fight crop diseases or which are resistant to weed-killing herbicides, and GPS (global positioning system) devices that allow a field to be tilled or planted very precisely.  Cloned and genetically modified animals are on the verge of becoming commonplace.  Conventional systems rely heavily on artificial and toxic methods to force higher plant and animal production and to fight diseases, weeds and pests.  Their basic approach to food and fiber production is to overpower and control nature, or natural processes, by using man-made materials and methods.

Unfortunately, the possibility of severe environmental problems is very high under conventional agriculture, such as soil loss (erosion) and degradation (including desertification, the spread of desert-like conditions), pollution by toxic chemicals, extermination of beneficial species (such as honeybees), and contamination of plant or animal foods by disease-causing microbes (for example, E. coli).

How do they compare?

A brief comparison of the principles and effects of sustainable and conventional agricultural systems is found in the accompanying table.  Some of the main differences include their basic underlying philosophies, which we mentioned previously, and their long-term environmental effects.

Conventional systems do much less recycling, but use expensive petroleum-derived fertilizers, herbicides and pesticides (both systems will also use petroleum fuels to operate tractors and other machinery).  We cannot continue using the earth’s finite petroleum reserves indefinitely.

Many, if not most, of the chemical inputs that conventional systems use have some degree of toxicity or other negative side-effects (for example, some fertilizers can kill beneficial soil organisms and cause soil to become hard).  These toxic chemicals can cause stresses to both plants and animals, often leading to poor health and disease or pest attack.  Unhealthy crops or animals produce poor quality food for people, with poor human health a likely result.

The advocates of conventional agriculture often point to its supposed efficiency and the low cost of food to consumers.  But that is only half the story, because they do not take into account the environmental damage and health-care costs, which are long-term in nature and are not direct agricultural expenses.  It is difficult to put an exact cost to millions of tons of topsoil eroded into the ocean, the treatment of sick people and animals, or the extinction of a species.

Sustainable agriculture tries to work with natural processes and to rely on recycling nutrient-containing materials (such as manure or crop residues) into the soil, where they are broken down by a multitude of beneficial soil organisms (from bacteria and fungi to earthworms and insects) and are made available to future crops.  Sustainable farmers (or gardeners) believe that healthy, low-stress plants or animals are able to resist diseases and pests naturally, and that they also produce high quality, nutritious food for people.  When healthful food is eaten, people should be healthy, so health-care expenses will be lower.  Toxic chemicals are seldom if ever needed in sustainable systems.

Sustainable farmers do as much as possible to preserve and maintain the natural environment.  Although the retail cost of sustainably-grown food is often higher than conventionally-grown, the value of more nutritious food and less environmental damage more than makes up for it.  Some comparison studies of the nutritional content of conventional and organic foods are found here.  In these comparisons, the organic foods consistently had more of desirable nutrients and less of potentially harmful substances (cholesterol, saturated fat, nitrate).

The critics of sustainable systems often say that they cannot produce as high yields of crops as can conventional systems, and that for the large amounts of food needed in today’s world, sustainable methods are inefficient, impractical and unprofitable.  Yet many comparison studies show just the opposite . . . at least much of the time.

There are many variables that can affect the results, but comparisons of conventional and sustainable (usually organic) systems in the United States and Europe have found that for most crops in most weather conditions, the sustainable crops yielded essentially the same or somewhat lower than conventional crops (only bulk quantity as volume or weight was measured, not nutritional value).  But where sustainable crops really excel is under drought or dry conditions, where because of the water-holding ability of “healthy” soil, crop yields far exceeded those of conventional systems.

The comparison of system profitability also is won hands-down by sustainable systems.  By not using expensive fertilizers, herbicides and pesticides, the profitability and energy-efficiency of sustainable systems outshines conventional methods.  In a six-year study (1978 – 1983) by theUniversityofNebraska, the organic system earned a net income of $125.95 per acre, compared to $94.58 for monoculture corn.

Although a huge conventional farm may seem more efficient than a small family farm, it requires extremely expensive large-scale tractors, planters and combines, while a smaller farm can function well without the latest, biggest and best equipment.  If the large conventional farm grows commodities (corn, soybeans, cotton, etc.) that are subsidized byU.S.government programs, this extra injection of money may make it seem that the conventional farm is profitable.  Many of the crops grown by smaller and organic farms (fruits, vegetables, etc.) are not subsidized, putting the sustainable farmer at a disadvantage.

Outside of the developed countries, most farming is done on a small scale by families.  They generally use more or less sustainable methods and generally only raise enough  food to feed themselves and maybe a little extra to sell and buy a few essentials.  Often the effectiveness of such subsistence farming could be greatly improved by educating the farmers to make a few changes that would increase the natural fertility of their soil or improve their animals’ health.  So, when proponents of high-tech conventional methods say that switching entirely to sustainable agriculture would cause massive starvation, we can only reply – not so!

Considering the above comparisons of conventional and sustainable agriculture, which do you think is better?  With the world’s human population soaring, now nearly seven billion and predicted to hit nine billion by 2050, the challenge of feeding everyone is tremendous.  Yet, with economic and political upheavals, the increasing depletion of natural resources and alarming environmental damage, can conventional agriculture last much longer?  You decide.