The Science of Everything Podcast - Episode 2: Organic Agriculture Part 1

Episode Date: July 18, 2010

A discussion of the history of organic agriculture, the philosophy behind it, and the main methods used. Also includes a look at the environmental benefits of organic farming, including the effects on erosion, water pollution and biodiversity. If you enjoyed the podcast please consider supporting the show by making a paypal donation or becoming a patreon supporter. https://www.patreon.com/jamesfodor https://www.paypal.me/ScienceofEverything

and welcome to episode two of the Science of Everything podcast. I'm your host, James Fodor. In this podcast, I discuss a wide variety of topics in both the natural and social sciences, exploring the many fascinating insights that the scientific method yields about the world around us. The topic for this episode today is organic agriculture. Just as a very brief introduction, organic agriculture is basically the idea of producing food without the use of artificial pesticides and fertilizers and other such things. but I'll give a bit more of an introduction later on.

So in this episode, I want to talk about, first of all, what is that organic agriculture? Give a bit of a background to the history, the core concepts of it, and the sort of size of the industry, and the outlook for the industry today. And then I want to move on to look at some of the core claims of organic agriculture, the arguments for why it should be adopted. The main ones are that it's good for the environment, and that organic food is of a higher quality, nutritionally in terms of taste and other things. And then I also want to look at the efficiency of organic agriculture in comparison to conventional

farming in terms of yields and costs and other such things. Okay, so first we'll start with what is organic agriculture. And before I get into that, I just want to make a note on the sources that I've used for this podcast and you can find the complete list in the show notes. I've tried to stay away from any publications or websites that were overtly pro-organic agriculture, you know if they said something to the effect of our mission is to promote the adoption of organic agriculture, etc. I didn't consider that to be a sufficiently non-biased source to be credible. I stuck mainly with government reports and journal articles and other sources that I found to be reliable.

Okay, so first of all, we'll start with the historical background to organic agriculture. Now, the term organic farming was first used by the UK agriculturalist Lord Northbourne in his 1940 book, Look to the Land. And another important work of the organic movement was called An Agricultural Testament, which was written by Sir Albert Howard, who was an agricultural advisor in British India. And he published his book around the same time as well, early 1940s. Both of these works made fairly similar arguments about the need to treat the farm as an organism in a sense, and utilizing the interdependencies found in natural ecosystems as a guide for how to construct a farm. Now, interestingly, the main focus of the organic movement today is

about artificial pesticides and fertilizers being bad for human health and also having a negative impact because of runoff into rivers and other things like that. But at the time, Northbourne and Albert Howard were mainly concerned about artificial pesticides and fertilizers because they considered they used to be unsustainable in the sense that it was sort of adding something external to the farm rather than building a self-sufficient, self-contained system like natural ecosystems did. So the concern of the sort of founders of this movement was somewhat different to the concern of those many agricultural proponents today, which is, I think, somewhat interesting. Later books built upon these pioneering works and included such things as Silent Spring

by Rachel Carson. That was published in 1962. which was about the effects of DDT and other toxins on birds and wildlife, and the one straw revolution by, and someone whose name I can't pronounce, Foucau or something like that, in 1975. These ideas about the problems of artificial pesticides and the need for a holistic, naturalistic approach to agriculture, all sort of got tacked on to the environmentalist movement, which grew up over the course of the 1970s and 1980s,

and all sort of got mixed up with that. and it all became came into the mainstream around the 1990s, which is when we see the takeoff of the organic food as a significant industry, and since then it's been growing very rapidly. Now, I just want to make a brief note on the anti-scientific attitudes of the original pioneers of the organic movement, particularly Northbourne and Albert Howard. I had a brief look at parts of their original writings,

and was quite, well, disturbed at their attitude towards science. I'll just read you a few brief quotes, and you can sort of make up your own mind. North Warren said, and this is a quote from his book, and you can see the full reference on the show notes, quote, food of better quality is food which has vitality, individuality, freshness. And then later on in his book he admits that vitality is a very unscientific term, end quote. Another one, quote, we have to live our lives in practice, and can very rarely wait for scientific verification of our hypotheses.

If we did, we should all soon be dead, for complete scientific verification is hardly ever possible. It is a regrettable fact that a demand for scientific proof is a weapon often used to delay the development of an idea, end quote. And Albert Howard also speaks very favourably of the agricultural methods used in 1940s, which is the time he wrote, India and China, even though such methods were responsible for the fact that hundreds of... of millions of people in those countries were living in dire poverty at the time, and in fact still are.

But anyway, that's just a bit of a side note. You can see that the basic point I wanted to make it with that is that the original proponents of organic hergogic did not base their conclusions on really good science. I mean, they did have some scientific background, and they made some arguments related to that, but it was primarily an ideological thing about, you know, they just felt that sort of self-contained farming system based on what traditional methods was better for various reasons. Okay, now, the basic concepts of organic agriculture. A fundamental principle in organic farming is to minimize its environmental impact as much as possible

while sustaining the farming system, end quote. According to the National Organic Standards Board, Organic Agriculture is, an ecological production management system that promotes and enhances biodiversity, biological cycles and biological soil activity. It is based on minimal use of off-farm inputs and on management practices that restore, maintain, and enhance ecological harmony, end quote. Basically, the idea is making the organic farm as self-sufficient as reasonably possible, that instead of basing the fertility of the soil on input of use of fertilizers, artificial fertilizers, this is achieved through other methods, which I'll talk about a bit more later, but particularly, application of manure. Another important idea is the maintenance of soil fertility and the quality of the soil, you know, keeping earthworms and other things in the soil, making sure it's

of a high quality, rather than just providing the nutrients need for the plants. There's a focus on the quality of the soil in and of itself, and just generally trying to minimize the environmental impact of the farm. And recently, organic agriculture has been steadily acquiring sort of new territory and concerns, including the whole movement of bi-local, local agriculture, the idea of carbon footprint, animal rights, fair labour laws, etc. But still, the fundamental core of organic agriculture has been, and still is, opposition to artificial fertilizers, herbicides and pesticides. That's the core element, and then there are these sort of other things that are tacked on. Opposition to genetic engineering is also another thing that generally goes along with organic

agriculture, but I'm not going to talk about that in this podcast because genetically modified food isn't, I think, deserving of a separate podcast all to itself. Okay, so what methods of production do organic farms use? You know, if they don't use too many pesticides or herbicides or artificial fertilizers, how do they keep their farm working? Well, weeds are indeed one of the biggest problems in organic agriculture, but there are a wide variety of methods that they use to deal with these. And these include mechanical cultivation, just weeding by hand or through machinery, crop rotation, which is moving crops around from season to season, so that they're not always growing in the same place. Cover crops, water management, pre-germination of weeds, a buried drip

irrigation, and a wide variety of other methods. From what I could tell, cover crops and mechanical cultivation and crop rotation are the three big ones that are used to keep weeds under control, I should say that cover crops are basically where you plant an additional crop sort of over or mixed amongst the main crop, and that helps to, it also helps to prevent erosion, but I'll talk about that a bit more later, but it, you know, by sort of taking up space and some of the excess nutrients, it, you know, prevents weeds from coming in and competing with the main crop. Cover crops usually, though, are not edible in and of themselves, so they do sort of detract from the main sort of resources of the farm, you know, you have to buy the seeds for them and plant them and so on.

So that's why they're not used so much in conventional agriculture because there are costs to doing so. US regulations require that organic foods be grown without synthetic pesticides without growth hormones. You also can't use antibiotics or anything that's genetically engineered. Chemical fertilizers and sewage sludge are also banned. Now, animals, to be certified as organic meat, they must consume only 100% organic feed, and they cannot receive antibiotics or vaccinations, which I find particularly bizarre, but I'll talk a bit more about that later. And there are also, in the UK at least, and I should say that the standards for what can be certified as organic differ from country to country, but they're generally fairly similar. In the UK, there are a whole bunch of requirements as to that the animals must have, you know, access to... to a certain amount of free space and a certain amount of certain size areas to live in and so on.

And I've got those in multi-tale on the show notes, but I just wanted to make the point that there are an extensive number of requirements to be certified organic, both in the inputs you use and the methods you use and how the animals are treated, etc. Okay, so a bit on the size of the industry. As of 2003, about 2% of food sales in the US and Europe were of organic foods. But the size of industry is growing very rapidly, about 15 to 20, per year, that's much more rapidly than the food industry as a whole. So organic foods are becoming increasingly popular in the West. Total land under organic cultivation varies wildly throughout the world.

The levels are generally much lower in the developing than in the developed world, which is perhaps not surprising, and they're higher in Western Europe than anywhere else. To give a few sort of benchmark figures, Switzerland and Austria have around the highest levels in the world, about 10% of land area, organic. UK and Germany are pretty high, they're both around 4%, Australia is about 2.3%, France and Spain, sort of more typical for some of the other European countries, are about 1.5%. The US is quite low, only about 0.2%. And China and India are very low, well, well below 1%. Now, initially, organic food production focused mainly around small farms, locally sold produce, etc. Today, organic food has become a big industry, with growth of 15% to 20% per year.

And so there's an increasing trend towards large-scale organic producers. You have corporate farms based on conventional technologies. You're increasingly seeing corporate farms based on organic technology because it's big business, very profitable. For example, in California in the late 1990s, over half of the organic food produce came from only about 2% of the organic farms, which obviously means that these 2% are very big farms and commercially run farms. So that's a bit of an outline to organic agriculture.

history and the current state of the industry. So next we're going to move on to the topic of, is organic agriculture good for the environment, which is probably the main claim made for organic agriculture, that it's good for the environment. Now, there are several topics that I want to look at that are generally argued to be the main benefits of organic agriculture for the environment. First, there's issue of pesticides. Organic agriculture doesn't use artificial pesticides, and that's argued to be of benefit. So we've got pesticides. Nitrate runs off and pollution, energy usage, biodiversity and erosion. So they're kind of the big five. And so I'll look at those in turn and then have an overall examination of the environmental impact

of organic agriculture. So pesticides. One big problem with pesticides is not so much their residues on the food, but actually just farm workers who are directly exposed, the pesticides, can contract a wide variety of illnesses as a result. According to the World Health, organization in 1992, about 3 million pesticide poisonings occur annually worldwide and result in about 220,000 deaths. So that's quite significant. But aside from those direct harmful consequences, there's also the issue of pesticides affecting the wider population. The main methods through which pesticides, which include herbicides, insecticides and fungicides, they're also grouped under the broad category of pesticides, the main ways they end up in the environment are through

aerial drift, so you know you spread fertilizer through by dropping it from planes or whatever, and it's blown away by the wind. Evaporation, surface runoff and leaching into groundwater. So surface runoff is, you know, you drop it on the surface and it runs off as a result of dissolving in rainwater and runs off on the surface, leaching into groundwater is pretty much the same thing except that it dissolves into the water once it's already underground and then flows underground to the groundwater. Now, the U.S. National Water quality assessment program reported that more than 95% of streams and nearly 50% of shallow wells were found to contain agricultural pesticides. Organic agriculture also suffers from this problem

of pesticide runoff, however, only about 10% of organic farms use pesticides on a regular basis, so it's a much smaller problem for organic farms. Now I should clarify that organic farms are allowed to use some pesticides, but only quote-unquote natural ones. And there's a list of ones that they're allowed to use, which basically are just the non-artificial ones. Now, just because something's artificial, just because something's natural doesn't mean it's safe, obviously. For example, arsenic is natural, a wide variety of drugs that are artificially made, which are good for us. So the fact that pesticide is natural really is largely meaningless, except that organic farmers are like to use them. But more to the point is that most organic farmers

don't use any pesticides at all, or only very small amounts. So that's why pesticide runoff is much smaller risk for organic compared to conventional farms. In one study of the four herbicides applied to a conventional plot of land, one of the herbicides had no current EPA maximum contaminant level, two were not detected at all in the water, and one was detected in the surrounding water, mostly below the maximum contaminant level of the EPA but sometimes peaking above the maximum contaminant level. And so that begs a question, what is a maximum contaminant level? Well, the important thing to realize is that just because

pesticides are found in most streams and wells, as I mentioned before, that doesn't necessarily mean that they're harmful. Because pretty much everything in any chemical or any substance is only harmful once a certain threshold is reached. And in fact, generally there's a dosage-dependent response so that the more of it you have, the more harmful it is. And in fact, for some things you have a little bit of it and it's beneficial, but then if you have too much, it becomes harmful. That really applies to pretty much anything you can think of, even water that applies to. If you drink enough water, eventually you'll drown yourself. So there's really

no such thing as a poison. One of the quotes that I read when I was researching for this podcast is that everything is a poison. It's just dependent on how much you have. So if you have too much of anything it can kill you. Conversely, sufficiently small doses of pretty much anything can be harmless. So just because pesticides are found in water doesn't really necessarily mean that they're a bad thing that's harmful, that we have to worry about that. It's all about how much it is. And so the EPA has set maximum contaminant levels for a whole bunch of different pesticides so that determinations can be made about whether or not it's harmful. And generally, of the study I mentioned before, 95% of streams have pesticides in them,

most of those are below the EPA thresholds for health. The conclusion is that organic farms do produce hardly any pesticide compared to conventional farms, but pesticide runoff probably isn't that big of a deal even for conventional farms. But I will talk a bit more about that later in the section about organic foods being of higher quality. So now I move on to nitrate pollution. Nitrate leaching refers to the phenomenon whereby nitrate leaching refers to the phenomenon whereby nitrate, in agricultural soils become dissolved in rainwater and are then carried down through the groundwater, collecting in nearby lakes and rivers. And this can have potentially negative impacts for human health,

and can also lead to eutrophication. Utrification is the process where, whereby a build-up of organic nutrients and rivers, wetlands, and lakes, leads to a population explosion of algae and other photosynthesizing organisms. Now, you might think this is a good thing, you know, we're getting more photosynthesizing organisms that seems to be helping the natural environment. But the thing is, once these organisms start to decay, aerobic bacteria begin to break them down. Basically, they start to rot. And in the process, the process of decomposing them uses up so much oxygen from the water that many fish and other aquatic creatures, and then by extension the birds and other species that are dependent upon those fish, are adversely impacted.

So basically, if you increase the organic nutrient content of lakes and rivers, you get a population explosion of algae. and then there's algae decay. In the process of decay, so much oxygen is taken out of the water that fish and other things die off in large numbers, and that's a big problem. I should say that nitrate is just a compound that's found in the soil that is a main sort of means by which nitrogen is stored in the soil. Nitrogen is a very important nutrient that plants need to grow, and it's one of the main things that's added to plants by artificial fertilizers is nitrogen, because it's often a limiting factor in plant growth. They need more nitrogen, and not enough of it is in the soil.

So, you know, that's why we add nitrogen. That's why we need fertilizers to add nutrients back into the soil that are not in there in sufficient quantities. Trouble is, as I said before, we add the fertilizers to the soil, but some of it gets dissolved in the groundwater, which is then carried into nearby lakes and rivers, and we get this problem of eutrification. Now, organic agriculture does not totally eliminate this problem,

but virtually all studies show significantly lower levels of leachable nitrates inorganic compared to conventional soils, often several folds. So organic is much better than conventional in this respect. Now, some studies have shown that levels of nitrates in drinking water do sometimes exceed regulatory limits. One study showed that 20% of conventional systems water found around conventional farms were above the limit. compared to about 15, 12 to 15% of organic systems exceeding limits. So there's a significant difference there. So it seems that organic farms reduce nitrate runoff mainly through their, first of all, their low use of nitrogen inputs.

They don't use artificial fertilizers, so there's less nitrogen put in the soil in the first place. Also, the use of cover crops and straw-based manure and lower stocking densities, which means lower number of cows or sheep or whatever, pigs per land area. These factors all help to limit the amount of water that's going to leach into the ground and then dissolve the nitrogen, the nitrate that's in there. So that seems to be why organic farms are better in the nitrate pollution area than conventional farms. Okay, so so far we've looked at pesticides and nitrate pollution and organic farms do come off significantly ahead of conventional farms. So now energy usage. Most studies agree that organic agriculture uses less energy than conventional agriculture.

Energy inputs include all things, all inclusive, so that includes the energy needed to produce pesticides and herbicides, energy needed to run the farm machinery, etc. However, when you factor in the lower yields of organic agriculture, and I will talk more about yields later on, and various other factors that come into play, total greenhouse gas emissions per unit of output of organic farms may not be significantly different to conventional farms, and that's very hard to measure, so not all studies show the same thing in that regard. As sort of implied before, organic agriculture definitely does have a lower energy usage on per area basis, but because of lower yields and lower stocking densities, when you take that as per

output, not necessarily so much difference. Okay, so the next question is biodiversity. Now, it's argued that organic farms encourage biodiversity. I mean, first of all, they reduce pesticide and nitrate pollution, which are, of course, inimical to biodiversity. You know, they kill animals and disrupt food webs. So that's obviously going to have a positive effect. But it's also argued that by maintaining cover crops and crop rotation, non-application of fertilizers, and higher organic nutrient content in the soils, that organic farms tend to attract, you know, they have a high diversity and number of microbes in the soil of earthworms and the soil of fungi, of other plants and insects living in the soils,

around the farm and studies have generally borne that up as being true. Organic farms definitely do have more nutrient-rich soil because of the fact as I just mentioned above, carbon crops, crop rotation, not as many fertilizers, etc. And this increase in the organic content of the soil does seem to be responsible for reducing water leaching and also protecting the crops from parasites and diseases in fact. It kind of makes sense in one degree. First of all, if the soil is healthier, plants are going to have more of a reserve of nutrients to a fight off parasites and diseases that might come up that might impact them. Also if plants are being treated with herbicides and pesticides, that's going to, there's going to be less need for them to develop their own

natural defense systems. And so when something comes up that the pesticides and herbicides don't help against, then the plants are going to be more vulnerable. So yeah, it does seem that organic farms are more conducive to biodiversity, both on the farm itself and in the wider, in the wider ecosystem. Last of all, I want to talk about erosion. Erosion is probably the biggest environmental problem facing agriculture at the moment from the research that I've done. A number of studies have shown that organic agriculture, mostly through use of crop rotation and cover crops, cover crops are particularly important because they kind of keep the soil held down and prevent it from being washed away, which is, you know, what erosion is. Removal of soil through water and wind,

basically. So studies have shown that organic agriculture can reduce this by some 30 to 50% which is significant. And as I said before, the main methods through which organic agriculture does this is to have cover crops or undercrops, less dense stocking rates. So for example, if you have fewer cows per hectare, then they're going to be eating up less grass. So you're going to have more grass on the paddock. And so there's going to be less tendency for wind and rain to erode the soil. However, there are some organic practices which would tend to increase erosion. For example, some organic techniques at least are tilling up their land more frequently as a need to keep out to combat weeds because they don't use pesticides, so that would tend to increase erosion.

Basically, erosion goes up, the more you turn over the soil, and goes down, the more plants and other things you have growing on the soil as a basic rule. However, overall, it does seem that organic heraldure does have much lower levels of erosion, as mentioned before. but once again, not zero levels of erosion. It's not like it totally prevents it. Okay, so what's the overall conclusion? Quote here from one of the papers I read, quote, a review of over 300 published papers

found that out of 18 environmental impact indicator areas, organic farming systems perform significantly better in 12, and worse in none, end quote. Another quote, a study carried out went further and calculated that the total external cost to the environment and to human health of organic agriculture was much lower than for conventional agriculture. End quote.

So it does seem that the claims made by the organic movement about having environmental benefits are valid. The fact that they don't use pesticides does result in much lower levels of contamination in the environment, although those environmental contamination levels that do occur are not necessarily as bad as they make out, and I will talk more about that later. Nitrate pollution, nutrification, and other related issues

are definitely much lower for our organic agonautical. basically because they don't use artificial fertilizers. Energy usage of organic agriculture is probably lower, although the impact of CO2 and greenhouse gas emissions is a bit more ambiguous. Biodiversity is definitely raised or maintained better by organic systems, and erosion, largely owing to the use of cover crops and a manure, which also helps to keep the soil down, is definitely much lower in organic systems. So overall, a big tick for organic agriculture in terms.

of environmental impact. I'm going to split this up into two. Next podcast I'll come back and talk about the remaining two questions, is organic fruit of higher quality and is conventional farming, how do they compare in terms of efficiency? And then I'll offer my concluding thoughts on the topic. So hopefully you learn something from this podcast. If you enjoyed this podcast, please help to spread the word by posting a positive review on iTunes or by sharing the podcast with a friend or someone else you know. If you have any questions, comments or suggestions, please feel free to contact me at my email address, FODS-12, that's FODDS12, at gmail.com.

You can also find the show notes for this podcast and leave comments at FODS12.Podbean.com. Thank you for listening, and I'll talk to you next week.