(rearranged and rephrased intro)
(→‎In regards to nutritional value: removed most of the section, consider it unfixable. Added opening paragraph citing meta-studies)
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* [[Water pollution]], including fertilizer runoff causing [[eutrophication]]
* [[Water pollution]], including fertilizer runoff causing [[eutrophication]]


===In regards to nutritional value===
===Human health===
The view that organic foods are ‘healthier’ than conventionally-produced foods appears to be based on the perception that organic foods have superior sensory attributes, contain lower level of pesticides and synthetic fertilizers and have higher levels of nutrients and protective phytochemicals.  
Organic foods are usually assumed to be healthier than conventionally-produced foods. Hundreds of studies have attempted to assess the whether conventionally-produced foods have different health effects from organically produced ones. In the last few years a few meta-studies have drawn differing conclusions based on those earlier studies. One meta-study of 237 studies conducted at Stanford concludes that "There isn’t much difference between organic and conventional foods, if you’re an adult and making a decision based solely on your health."<ref>http://med.stanford.edu/news/all-news/2012/09/little-evidence-of-health-benefits-from-organic-foods-study-finds.html</ref>. Another meta-study lead by researchers at Newcastle University based on 343 earlier studies found that conventionally-produced crops contained 18-69% less [[antioxidant]]s, were four times as likely to contain pesticide residues, and had, on average 48% higher concentrations of [[heavy metals]] (including [[cadmium]]) than organically-produced crops. <ref>http://research.ncl.ac.uk/nefg/QOF/crops/page.php?page=1</ref>


A limited number of studies have compared the nutrient compositions of organically- and conventionally-produced crops.  Upon review of the studies, it is obvious that clear-cut conclusions cannot be drawn from the present scientific literature, since very few of the studies conducted to date adhere to ideal criteria for evaluating effects of the two growing systems on nutritional quality <ref>Williams 2002</ref>.
Many supporters of organic agriculture rely on personal experiences and beliefs when choosing organic over conventionally-produced food. "Although, as scientists, we may deplore the fact that people are swayed by non-scientific views, the fact is that a lot of them are. Despite the arguments presented by Trewavas, many people believe that organic production systems produce better food, care more for animal welfare and are kinder to the environment," <ref>[http://www.nature.com/nature/journal/v412/n6848/full/412677a0.html "Organic movement reveals a shift in the social position of science"] Annette Mørkeberg & John R. Porter ''Nature'' Number 412, page 677, August 2001</ref>.
 
However, there is disagreement.  Regardless of the presence of scientific literature, many people hold the belief that there is a difference in nutritional value between organically produced food and conventionally produced food.
 
The extent of disagreement is well illustrated by two diametrically-opposed statements currently published on the web.  Whereas an editorial on the website of the American Council on Science and Health states “Not a single published study has shown any difference in the nutrient content of organic versus conventional farm produce,” <ref>The above text was not directly cited. No article containing that exact phrase is currently hosted on acsh.org. Reference should be replaced.</ref>  the Mothernature site (www.mothernature.com) supports the view that organic food is healthier than conventionally-grown food “… based on research in Denmark and Germany showing that organically grown foods contain higher levels of nutrients.” <ref>The domain mothernature.com now hosts a different website than the one referenced here. The original source was probably of low quality to begin with. Reference should be replaced.</ref>
 
Many supporters of organic agriculture rely on personal experiences and beliefs that make them more receptive to the idea that there is a difference between organic and conventionally produced food. "Although, as scientists, we may deplore the fact that people are swayed by non-scientific views, the fact is that a lot of them are. Despite the arguments presented by Trewavas, many people believe that organic production systems produce better food, care more for animal welfare and are kinder to the environment," <ref>[http://www.nature.com/nature/journal/v412/n6848/full/412677a0.html "Organic movement reveals a shift in the social position of science"] Annette Mørkeberg & John R. Porter ''Nature'' Number 412, page 677, August 2001</ref>.


=== Why do farmers use chemicals? ===
=== Why do farmers use chemicals? ===

Revision as of 07:44, 25 February 2016

Conventional farming, also known as industrial agriculture, refers to farming systems which include the use of synthetic chemical fertilizers, pesticides, herbicides and other continual inputs, genetically modified organisms, Concentrated Animal Feeding Operations, heavy irrigation, intensive tillage, or concentrated monoculture production. Thus conventional agriculture is typically highly resource and energy intensive, but also highly productive. Despite its name, conventional agricultural methods have only been in development since the late Nineteenth Century, and did not become widespread until after World War 2 (see: Green RevolutionW).

Conventional farming is usually contrasted to organic farming (or sometimes sustainable agriculture or permaculture), as these respond to site-specific conditions by integrating cultural, biological, and mechanical practices that foster cycling of resources, promote ecological balance, and conserve biodiversity.[1] Rather than using synthetic fertilizers, pesticides, growth regulators and livestock feed additives, organic farming systems rely on crop rotation, animal and plant manures as fertilizers, some hand weeding and biological pest control [2]. Some conventional agriculture operations may include limited polyculture, or some form of Integrated Pest Management.

Conventional versus organic farming

Advantages and disadvantages

What we are doing with new agricultural technologies has positive and negative consequences. It is not easy to decide what is good and bad, but if we analyze the positive and negative aspects of the way that we produce food, perhaps we will be able to improve upon the good things, and reduce the negative impacts of the bad.

With conventional farming it is possible to produce much larger quantities of food, on less land and with less input of (some) resources and manual labor than ever before in history. With rising food costs and millions of people starving all over the world, it seems like we have a moral obligation to use conventional methods to produce large amounts of food at affordable prices.

Because many of the effects of conventional farming are unknown, and because of how many of the effects may be irreversible and harmful, it may be safer to stick to what we have been doing for hundreds of years. It may be considered irresponsible to continue using pesticides, irradiation and GMO’s when we really don’t know what the side effects are.

As a result of these industrial farming conditions, today’s mounting environmental stresses are further exacerbated. These stresses include: declining water tableWs, chemical leachingW, chemical runoff, soil erosion, land degradationW, loss in biodiversityW, and other ecological concerns.[3]

In regards to ecology

There is a common perception that organic farming will save the environment. Is this true? Note that there are many factors in how sustainable farming practices are, besides use of chemicals. E.g.:

Human health

Organic foods are usually assumed to be healthier than conventionally-produced foods. Hundreds of studies have attempted to assess the whether conventionally-produced foods have different health effects from organically produced ones. In the last few years a few meta-studies have drawn differing conclusions based on those earlier studies. One meta-study of 237 studies conducted at Stanford concludes that "There isn’t much difference between organic and conventional foods, if you’re an adult and making a decision based solely on your health."[4]. Another meta-study lead by researchers at Newcastle University based on 343 earlier studies found that conventionally-produced crops contained 18-69% less antioxidants, were four times as likely to contain pesticide residues, and had, on average 48% higher concentrations of heavy metals (including cadmium) than organically-produced crops. [5]

Many supporters of organic agriculture rely on personal experiences and beliefs when choosing organic over conventionally-produced food. "Although, as scientists, we may deplore the fact that people are swayed by non-scientific views, the fact is that a lot of them are. Despite the arguments presented by Trewavas, many people believe that organic production systems produce better food, care more for animal welfare and are kinder to the environment," [6].

Why do farmers use chemicals?

Modern farmland is claimed to produce 200 percent more wheat than the same area did 70 years ago. Hence switching to organic farming would lead to a reduction in output, e.g. by 20% for corn.[7] The figure is plausible, but we need more than one unattributed figure.[8]

Pesticides

Most of the pesticides in our food, by far, are natural pesticides produced by the plants. This leaves open the question of whether the artificial chemicals are worse for us. After all, not all substances are the same, and some (such as DDT) linger in the environment for far longer. It's also true that something is harmful given to lab rats in large quantities, yet not significantly harmful in small quantities - or even beneficial, since there has been research suggesting that toxins in small doses actually benefit an organism by making it react to the mild stress.[verification needed]

Many natural chemical compounds are also toxic or carcinogenic in large quantities, but we consume them in small quantities. Everything has a toxic dose - even water, salt or any nutrient.

There is a common perception that "the poisons are killing us." So why are we living longer than ever? If there is a negative effect from these traces of chemicals, the effect is much smaller than positive changes in modern times (e.g. better medicines and medical treatments).

Note that these arguments are not saying that "pesticides are good for you" - using them inappropriately, without following directions, has the potential to be very harmful. But when used properly, they appear to not be significantly harmful, and may not be harmful at all. Worrying about them may do us more harm than the chemicals themselves.

Fertilizers

There's actually little doubt that fertilizers harm ecosystems. But is this inevitable, and what are the alternatives?

Limited use and precise application reduce the effect of eutrophication on waterways.

More recent discoveries, e.g. the role of soil fungi, the impact of compost teas, and terra preta, show that there may be much greener ways to create abundance in food production.[verification needed] However, this knowledge is still in its early years - the knowledge is still being developed, and the valuable knowledge that already exists has not yet spread widely.

Nitrogen sources

Borlaug said:[8]

Even if you could use all the organic material that you have--the animal manures, the human waste, the plant residues--and get them back on the soil, you couldn't feed more than 4 billion people (and) you would have to increase cropland area dramatically... At the present time, approximately 80 million tons of nitrogen nutrients are utilized each year. If you tried to produce this nitrogen organically, you would require an additional 5 or 6 billion head of cattle to supply the manure.

This appears to not consider the impact of nitrogen fixation,W for example by legume crops. (This is another argument for vegetarianism and veganism being greener - less methane-producing cows, and more legume crops to replace them, which will also produce nitrogen.)

Currently enormous amounts of nutrients are thrown away in our sewage. Through humanure this can be salvaged, but may not be suitable for many food crops, especially where the food is close to the ground.

GMO's

Conventional food production often utilizes GMO’s (genetically modified organisms) which are different from plants and animals that have been selectively bred.

There are environmental drawbacks of using GMO’s. One is that it is difficult to control the reproduction of plants, especially when they are growing in an open environment, and not contained within a structure such as a greenhouse. When there is a farm with GMO’s nearby another farm, there can be a problem with crossbreeding between the two varieties of plant. This can result in genetic drift which can have negative impacts for farms which produce heirloom varieties. When this effect is coupled with the terminator gene (a gene inserted in plants by companies which produce GMO’s, which prevents their seeds from producing viable offspring) this can have devastating effects on heirloom varieties, and for farmers who have been keeping their variety for generations.

Notes

  1. Definition according to the USDA
  2. "Nutritional quality of organic food: shades of grey or shades of green?", Christine Williams Proceedings of the Nutrition Society 2002
  3. Brown, Lester R. Plan B 4.0: Mobilizing to Save Civilization. W.W. Norton, 2009.
  4. http://med.stanford.edu/news/all-news/2012/09/little-evidence-of-health-benefits-from-organic-foods-study-finds.html
  5. http://research.ncl.ac.uk/nefg/QOF/crops/page.php?page=1
  6. "Organic movement reveals a shift in the social position of science" Annette Mørkeberg & John R. Porter Nature Number 412, page 677, August 2001
  7. Exposing the organic myth, BusinessWeek.com (msnbc.com). (The claim about the 200% increase for wheat is made on page 2).
  8. 8.0 8.1 Billions Served: Norman Borlaug interviewed by Ronald Bailey, April 2000, on Reason.org - this is a consistently skeptical and conservative site, including against mainstream science, so it needs to be checked for bias and selective reporting; however BorlaugW is a Nobel laureate and an influential scientist, so his interview is certainly notable.
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