The Habitable Planet: A Systems Approach to Environmental Science
Agriculture Interview with Peter Kenmore
Interviewer: Where do you conduct your research?
PETER: Anywhere that rice is grown, most of which are in Asia, but some are in Africa and Latin America and the Middle East. I’ve been doing this for twenty five years. I like working with the people who work in agriculture because farmers are managing more ecosystems than any other group of people on earth. They’ve got interesting questions and interesting observations. And I like the idea of thinking about crops and food production from an ecological standpoint. If it’s rice, there’s also a tremendous political standpoint. And I like thinking about that as well.
Interviewer: How did you first get interested in science?
PETER: I had outrageously good fourth grade and fifth grade science teachers—one of whom had a Doctorate from MIT. She developed a science curriculum based on everything from trees to the inner anatomy of a chicken and got us all very excited about it. That’s where it started and I always liked it. I had good science teaching all the way through. Sometime in the late ‘60’s, so that means towards the end of High School and beginning ‘70’s, which means college, I got interested in ecology. That was around the time of the first Earth Days in the early ‘70’s. So instead of the ninety-five percent of my college classmates who were majoring in biology who then went on to Med School, I said I would prefer to work outdoors and thought about evolutionary biology for a while. But I felt that it was important to do applied work and so that led to AG School. To come out with a Harvard Degree in Evolutionary Biology and go to AG School was an interesting contrast.
Interviewer: Why study agriculture? Should we be more concerned about climate change and energy resources?
PETER: In this U.N. Food and Agriculture Organization, the definition of agriculture includes crops, but also includes rangelands. It includes managed forests. It includes managed fisheries, which are all the inland aquaculture kind of fisheries, but also some of the managed coastal fisheries. So there’s a tremendous scope. If you add all of those things up, it’s about forty-one percent of the Earth’s land surface. The marine stuff is much smaller. But in terms of land surface, it’s a tremendous part of the world and being managed by people who don’t necessarily have specialized education, but do have tremendous experience in local culture to bring to bear on those management questions. I think that it’s very important vis-a-vis human-generated climate change as well as other issues that you’re talking about to engage and involve agriculture in those problems and in trying to put agricultural management on a more ecologically informed basis.
Interviewer: How did you first get involved working with agricultural science?
PETER: When I was a junior in college, I read two papers. One paper was about what’s now called classical biological pest control, which means when a pest or a bad guy bug has gone to a new part of the world and thereby escaped the good guy bugs that co-evolve with it and its whole ecosystem population is unrestrained. It becomes a terrible pest. You can reunite them, bring the good guy bugs over from the place of origin of the bad guy bug, plunk them down into the same ecosystem as the bad guy bug, you can reestablish biological control. As a matter of fact that was really exciting. It was understanding ecosystems and intervening in a way that could reconstruct, or at least put on a path of reconstruction, all these kinds of ecosystems. I also read a paper about the International Rice Research Institute in the early ‘70’s, where they had recently, at that time, effectively doubled potential rice production for most of the rice growing areas by breeding strains of rice that weren’t sensitive to photo-period. That meant that you could plant rice any day of the year. And that was exciting. Both those things were happening in the early ‘70’s. And at that same time, Vietnam was winning its war with the United States. Most of us who were students were very much engaged in not only protesting the war, often for selfish reasons, but at the same time trying to think about whether we can do something to make up for what was obviously bad policy and a real misuse of American and industrial power. The idea of working in rice was very appealing. And in fact, I’ve been able to work in a lot of rice paddies since then, including in Vietnam. And that’s been very satisfying.
Interviewer: Why is rice so important?
PETER: Rice now, and probably for the last four or five thousand years, feeds more individuals of the species homo sapiens than any other food plant. Hugh Thomas, a historian who wrote a history of the world, said that a one sentence summary, if one talks statistically of the last ten thousand years, is “the age of rice farming,” because more human beings have practiced rice farming than any other occupation during that ten thousand years. For both those reasons rice is really important. Evolutionarily why is it a good bet? Because it grows in places that are flooded. You can grow it in places where other crops won’t grow. The flooding tends to kill most of the weeds that would grow up and compete with the rice. So you’ve got an added advantage. You can put it into what would otherwise be a marginal environment. Often, that environment gets a little bit of help in terms of water carrying silt and nutrients downstream from weathering of geological formations, but also the ecosystem in the water itself includes microorganisms that fix nitrogen, so that you’re adding nitrogen into every square meter of the rice paddy, maybe thirty or forty kilos of nitrogen worth every year free. For those reasons – the water is assured that the weeds are out-competed and there’s a bit of an extra kick of nitrogen – rice has been a good bet. Therefore civilizations grew up with it. You’ve got loads of places where folks have been able to count on a harvest. If you can count on a harvest three out of every four years, you’re doing much better than in a lot of rain fed areas growing things like wheat, where you may only get two out of every three years. So it’s a good bet.
Interviewer: How important is rice as a source of food for the world population?
PETER: Rice, as a direct harvest crop, is the staple food of more people than any other crop. Production of wheat is close. But more rice goes directly into people than of wheat. Wheat goes also into industrial uses and other kinds of uses. Rice mostly gets into people. And the countries and cultures that grew up on rice depend on it a lot.
Around thirty percent of the world wheat production is traded internationally. It’s more like four or five percent of the world’s rice production. It’s local. It’s an important thing in a local politics, in the local system. So it’s important for all those reasons as well as the absolute numbers of people that eat it. The quality of how rice fits into culture and politics is different from other crops.
Interviewer: Why did the “Green Revolution” happen? Why was it necessary for an intensification of agriculture?
PETER: Demographic transition, which is when things like basic nutrition and medical care and public health interventions hit a country where they haven’t been. So you get a quick increase in the survival rate, particularly infant survival and child survival; you get an increase in the number of kids that each family has. The death rate’s gone down. The birth rate goes up. And population grows very quickly. That happened to a good deal of the world with the end of colonialism after World War Two. Population zoomed up and began to outpace food production. So the Green Revolution was a way to use plant breeding, to change the architecture of particularly wheat and rice, to a lesser extent maize, but particularly wheat and rice, by putting in more grain, less straw, better light penetration of a shorter stalk, much better conversion of light energy through photosynthesis into plant tissue, and by being non-photo period sensitive so that you could grow it starting any day of the year. In most of rice growing Asia, you’d grow two crops instead of one in a year which was necessary in the sense that food supply was getting risky. After the Green Revolution, it wasn’t risky. It depended on those varieties. It depended on irrigation water.
One would have to say now it depended on the right kind of market incentives, which were often very heavily subsidized, depending on the country. There was a lot of government intervention in markets, which is the case in rice anyway. There are very few countries in the world where rice is sold at a market price, because it’s just too risky. You have to intervene to keep it within certain bounds. At that time people presumed that they would also need insecticides, in particular. This wasn’t true. It was a mistake. But the fertilizers worked and that was good. The pesticides sometimes worked and sometimes created a contradictory result, i.e., you sprayed insecticides in the rice field and you got five hundred to a thousand times more insects that were eating rice than you had without the insecticide. That was a mystery. What was the solution of the mystery? The beginning of the solution was to see that in any agricultural field, but in particular in rice, in this case, there are not just two ecological atrophic levels. It isn’t just the rice and the things that eat rice. There’s the rice, the things that eat rice, and the things that eat the things that eat rice. So you have three levels. And when you spray, you kill both top levels, except for the eggs of the pests that are inside the rice. When they hatch, there’s nothing to eat them and they go on happily reproducing. And you get a population explosion. This is called pest release or pest population release. It means that the pest population is freed from its natural controls. And that’s what happened in rice. And so you had all sorts of insect pest outbreaks when insecticide use went up together with fertilizer use in the use of the new seeds. There are interesting little anecdotes. For example, around 1968, the government of the Philippines brought out a team from the Harvard Business School. There were a bunch of seminars with people saying the whole way of increasing food production is to get people to absorb more inputs. You know – straight Harvard Business School case method, classically applied to get everybody thinking about pushing inputs based on incomplete science. A lot of what my work was – in Asia starting in ’77 through ’97 – a lot of that work was to analyze why the results were going opposite to the direction that they were expected to, and then how to convince policy makers to change incentives, to remove subsidies for insecticides.
Interviewer: Define “inputs.”
PETER: Inputs is an economist’s term. It means anything you have to buy to put into the ground or into the fields. So an input can be water if you have to build an irrigation canal. It can be seeds if you buy them, instead of reused ones from your last harvest. It can be fertilizer. And it can be pesticides. So the object of the Business School approach was to increase consumption and to increase demand for inputs. But the scientific problem was that the inputs were not all necessary and some of them created a problem instead.
Interviewer: If pesticides decreased yields, why were so many farmers using them?
PETER: They got them free in many cases. The incentives set by policies in the 1960s and ‘70s were often perverse, so that when the price of fertilizers or pesticides was reduced artificially by government investment, then farmers used more of them. Farmers weren’t being asked to make a market manager decision. They were basically told that they would become absorbers of and users of these inputs. The release of the insect pests in the rice fields didn’t happen immediately; it usually took a certain number of generations, maybe even four or five years worth. If the Green Revolution rice varieties were released in 1966, ’67, the first pest outbreaks that were being regularly reported and documented were around 1970. And from that time on, all through South and Southeast Asia, every year, different countries would report problems like this. The first response was spray more. And that often created more of a problem. The second response was breed rice varieties that taste bad to the insects and therefore control the insects with the rice variety, but keep spraying them anyway. I arrived in ’77 and this was in the middle of all of this, when they realized that once you had the first set of resistant varieties, the insects kept evolving. Mr. Darwin is still correct. Under that tremendous selection pressure, they evolved to be able to eat the resistant varieties fairly quickly so that you had a boom and bust cycle. You had pest outbreaks, resistant variety, pests collapse, selection pressure, evolution, pest outbreaks, and the pests kept breaking out because you kept spraying everything. So you made a very complicated system, driven by central governments making deals with input suppliers, whether it’s fertilizer companies or pesticide companies, and making sure that farmers used all those inputs, sometimes with encouragement from the military, depending on the country you were in. They then went into a cycle of pest outbreak followed by collapse followed by outbreak followed by collapse.
The International Rice Research Institute, which was producing most of these varieties, was curious to know what was going on. Interestingly, if one looks back at their annual reports, they describe an experiment where they were selecting rice to be resistant to the rice insect that is the sentinel species called the rice brown plant hopper. They said in the caption of one figure, in the footnotes, that we had to spray the field with insecticides in order to build up the pest population. This was in the technical description because they were good scientists and they recorded everything they did. But there was a disconnect between what was happening in the research station and the policy makers who kept saying we must use these insecticides.
Interviewer: When were pesticides first used?
PETER: In rice, insects and rice plants and human beings have been coevolving for five thousand years. Since there’s ten generations per year in most of the tropics, that’s fifty thousand generations, which is a tremendous amount of co-evolution. Until the 1960s, in most of those tropic countries, the rice was grown without any insecticides. Starting after World War Two and particularly the end of the ‘50s, early ‘60s, more insecticides were used. And once it was clear that there was enough naturally occurring biological control in rice fields that could be factored into the management by reducing the amount of insecticide used, we were able to keep the pest populations lower enough to get a good harvest of rice without using the insecticides.
Interviewer: How are pesticides applied?
PETER: Knapsack sprayers. It’s a metal can on your back that you put it on with straps. Before you put it on, you fill it up with twenty liters or more of water and you mix some highly toxic substance in it and close it down and then you carry it. You have a handle that builds up pressure inside that can and you have a lance that you can spray. But as you spray it, you’re walking into it which means you’re coating yourself with this stuff. So we put a handkerchief over our face. The problem is that if you’re walking into water vapor and you’re breathing out water vapor, and you’re sweating, in about a minute or two the handkerchief is completely saturated with water. And at that point, it doesn’t stop anything- the molecules are just happily coming through and you’re soaking them into your mouth and your nose and you’re inhaling it and you’ve got it on your tongue. So it’s a risky business. And this assumes that the sprayer is in good repair. Ninety percent of knapsack sprayers are not in good repair and the seals leak and the lance connections leak so that you’re covering your lance hand with concentrated chemical every time you tilt. And if you think about being in a rice paddy, where you have water up above your knees and you’re picking up one leg and coming down, picking up the other leg coming down, this thing is tilting through a range of about a hundred and twenty degrees. So it’s sloshing around and tilting and you’re getting soaked. It’s a risky experience.
Interviewer: What do the toxic chemicals do to bugs? What do the toxic chemicals do to human beings?
PETER: There are two kinds of toxic chemicals in killing bugs. Ninety-eight percent of the ones that are commercially used in fields attack the bug’s nervous system. The cheaper ones especially stop an enzyme acetyl cholinesterase, which keeps your nerve signals going from the end of one nerve cell to the beginning of the other. Some of them attack the nerve cell in the middle of the cell instead of at the end of the cell. Most of the organophosphates, many of these cholinesterase-stopping insecticides started out as weapons. They were the product of munitions research. The other two percent stop the insect’s ability to molt. So if you have something that disrupts that process, you dehydrate and die if you’re an insect.
The chemicals do the same thing to human beings although they have a harder time reaching the nervous system of the human beings. They may be broken down by enzymes before they reach it, but all of the chemicals, all of the insecticides, of that ninety-eight percent, are toxic to people. And working in a field, where you’re working hard physically under hot conditions, makes you even more vulnerable, more vulnerable to being poisoned. When we talk to a group of farmers between twenty and twenty-five percent of small scale farmers growing cotton can tell you explicitly how they were poisoned within the previous twelve months, how they got so sick they couldn’t work, but may never ever see a doctor or a clinic. But they can describe the symptoms so clearly that we know that they were poisoned.
Interviewer: What is integrated pest management?
PETER: Integrated pest management is the process of managing crops so that the maximum service of pest controls provided by the naturally occurring species and human interventions don’t disrupt naturally occurring species doing their job. Integrated pest management means thinking about crops as ecosystems and adding things like resistant varieties, time of harvest, cultivation practices, fertilizer levels, and, in the last step, pesticides, only when the naturally occurring pest control isn’t keeping the pests to the desired levels. Integrated pest management accepts that there will always be some pests in every field. If there are a low number of pests, they provide food for the natural enemies. If there are too many pests, one should intervene. Sometimes one can intervene with a biological introduction, which can be, for example, a pathogen, like a virus or bacteria that eats insects. Sometimes, in rare cases, one can intervene by introducing an insect from a different place, who will then naturally go in, eat pests, reproduce, and stay in the field eating the pests from then on. Integrated pest management uses all of these approaches. While supporting increased crop production and increased yields, it tries to avoid disrupting the natural ecosystem of that crop field.
Interviewer: When did Integrated Pest management (IPM) begin?
PETER: IPM generally began in the late 1950s. Pesticide-based pest management didn’t work, because insects got resistant to pesticides and because they killed natural enemies and released pests. Rice IPM was given lip service starting in the early 1970s, but it was probably the mid to late ‘70s that people made a serious attempt to use varietal resistance to replace insecticide use. It wasn’t until the late 1970s in most of rice-growing Asia that the idea of conserving the natural enemies and thinking of the rice field as a managed ecosystem began to be commonly discussed.
Interviewer: What has been the relationship between pesticide use and rice production?
PETER: Pesticide levels went down after policy interventions from central governments. Rice production continued to go up. Food grain production as a whole continued to go up. Clearly, food grain production wasn’t connected to pesticide use levels. The pesticides had overshot. There had been an over use of pesticides. In India it was possible to reduce the annual use of pesticides by about thirty thousand tons a year out of a beginning number of about seventy-two thousand tons. In Indonesia the reduction was about ten thousand tons out of an initial base of twenty-five. And rice or basic food grain production kept going up.
Interviewer: Did integrated pest management originate with Rice?
PETER: Integrated pest management started out first in cash crops and in perennial crops, such as trees. Oranges, apples, oil palm, rubber, cocoa, coconuts, all had pretty good engrained pest management before rice did. The number of rice farmers is so many thousand times greater than the number of the other kinds of farmers, that you’re reaching thousands more people. Although the science, the research side of things, was earlier in the perennial crops in terms of reach and scope and importance to the national policy makers, it was important to get into for grain crops.
Interviewer: What is a farmer field school?
PETER: A farmer field school is a school without walls. It’s a school that works in a community of farmers almost all of which are in developing countries. It’s a group of fifteen to thirty farmers that meet regularly during a crop season- from the time they start planting to the time they’re harvesting. They start by looking at the crop, by looking at the size and quality of the plants, and then by looking at the different kinds of insects and fungi that are observed, bringing samples back, counting, coming back from the field, splitting into working groups, and then each working group giving a mini seminar of five or ten minutes to the whole field school on what they observed in the field. Usually a field school will also have some special topics that may have to do with new kinds of varieties that are available or an economic analysis of an alternative crop or a discussion on irrigation scheduling or the repayment interest rate on loans, and other topics that start from the field itself but grow into different areas. Farmer field schools sustain themselves. Usually, the first season is paid for by government program. But, second, third, fourth seasons of activity by the same groups of farmers are paid for with their own money and often they will grow a cash crop, study it, optimize it, and use the proceeds of the sale of the cash crop to keep the group going.
Interviewer: What effects have farmer field schools had on rice production?
PETER: Rice yields in total production in South and Southeast Asia have been increasing prettily steadily for the last twenty-five years, in some countries even for the past forty years. The rate of increase tends to go up and down. But there is increase. The farmer field school, which is associated with a reduction in pesticide use, has been able basically to substitute brains for chemicals, and in that sense the yields stay up, the growth rate stays up, but less chemicals are used. Most of the reduction in pesticides has come about from high level policy changes that took the subsidies away. Farmers were being forced to buy pesticides at something closer to a market price instead of a heavily subsidized cheap price. Their use went down. With farmer field schools they were empowered enough to grow the rice while using less pesticides. Total number of people who have gone through field schools now is between two and three million. There are a lot of rice farmers in Asia; there’s certainly hundreds of millions. So two or three million is a very small percentage. But in those areas pesticide use has gone down. And the yields continue to go up as they do for the other parts of the country, and increasingly, national policies are reflecting some kind of a field school element in a agricultural education farm level. Something else that’s important about field schools is that these are people who have never finished formal schooling. It uses principles of non-formal adult education. It looks at inquiry- based approaches to science, which actually have been developed in elementary school science teaching around the world by important figures of the past like Brenda Lansdowne.
Interviewer: What is the relationship between scientists and farmers?
PETER: In a system of farmer field schools, where farmers learn some ecology and they learn some crop physiology and they learn things about water supply, they start asking more and more difficult questions. Governments are more open to the idea of forums that include scientists and farmers. And those forums are often a real interesting experience for scientists because they’re being asked very difficult questions by farmers in language that’s more sophisticated than they expect farmers will use. It scares them at first but usually, they come around and it gets them to be excited about the work because they realize there’s a whole lot more people that might be interested in their work than they thought there were.
Interviewer: Who has the right answer, scientist or farmer?
PETER: Scientists don’t have the answer. Scientists produce an answer. Farmers produce an answer. The experience of doing research as a farmer on one’s own farm is exciting. Discovering something new, asking a question in the field, making observations, and finding out an answer to that question gives you ownership of that answer in a way that no reading and no teacher will ever be able to do. If you hear something, you forget it. If you see it, maybe you’ll remember it a little bit longer. But if you discover something, you own it. And that becomes part of your problem solving. And because you discovered it, you can adapt it later.
It’s not about what the farmers give the researchers, although they do give the researchers a lot. It’s what the farmers give themselves when they’re doing science. We talk about experiential learning. This does not mean learning by doing. Experiential learning is a learning process that gives greater value to your own experience. It means that your experience as a farmer is worth something. The observations you make, the patterns that you perceive. When you think about a crop having two kinds of bugs, the ones that eat plants and the ones that eat other bugs, it changes the way you think about that crop. It means that you’re conserving something greater than just the leaves and the roots and the seeds. You’re conserving the crop-associated animals with the crop-associated biodiversity. And that’s part of your normal management. When you think about that, you think twice or three times before you start spraying it. You think twice or three times about the impact of a new variety. You think about ways of testing new technology instead of adopting it.
Interviewer: What is the discovery moment for the farmer?
PETER: The discovery moment that we hear about from farmers most frequently is, understanding that there are at least two kinds of bugs in the field. There are bugs that eat plants. And there are bugs that eat bugs. That paradigm doesn’t exist before the field school. For anywhere from ten to forty years both corporate and government communication campaigns have been telling them all bugs are bad. Spray all bugs and kill all bugs. When they begin to wrestle with the idea that there are two kinds of bugs, that there are good bugs and bad bugs, that there are bugs that are defending the rice, as well as bugs that are attacking it – that’s the discovery for them that they come back to again and again.
If a farmer goes into a field and picks up a bug and goes to a trainer and says, “I found this bug. What is it?” And if the extension worker replies, “That’s the wood spider.” the moment’s dead. There’s no more learning. You’ve proven how powerful the extension worker is and have nothing that the farmer can go with. Part of the training of the trainers, part of the training of facilitation, is never answer a question with an answer. Always answer a question with another question.
You say, “It looks like a bug. Where did you get it?”
“I got it over there. I got the bug in that point of the field.”
“Well, let’s go look at it. Are there more of them?”
“Yes, there’s another one.”
“Great. What’s it doing?”
“Well, nothing right now. Wait. It started moving.”
“Where’s it moving? Is it moving?”
“Well, it’s on the water now.”
“Cool, it’s on the water. Well, what’s it doing now? Let’s look at it some more.”
Every moment is responded to with another question. That’s discovery. Supporting discovery, supporting the production and, and ownership of knowledge and of using science concepts in the field: the concept of atrophic level, the concept of a predator; the concept of a bug that lives inside the egg of another bug. These are all things that can be shown. Then you go from observation to experimental manipulation.
Interviewer: Describe what happens at a farmer field school?
PETER: The first thing is farmer field schools have to happen early in the day. If you do four hours of field work starting at eight thirty in the morning, in latitude less than five degrees close to the equator, you’re falling over in an hour and a half because it’s so hot. The first thing you do is split into four or five groups and go out in the field in these different groups and look at different parts of the field and look at the plants and the bugs. You can also look at the water conditions. Make collections. Count at least five to ten plants, count how many kinds of bugs and how many of each kind you see. It doesn’t make any difference what name people use. They use a name that makes sense locally. Then they spend the next forty-five minutes or so making a poster. Just a poster, just like in a scientific conference, you have poster presentations. Then the next phase is each group will present. On one side of the plant are pictures of the pests. On the other side of the picture are the natural enemies so you get a sense of the balance of nature.
You can go through the whole season watching the plants gets bigger and the bug populations changing. Bad bugs going up. Good bugs going up. Bad bugs going down. Good bugs sort of staying the same. You watch these fluctuations. We may look at an x y coordinate graph of population against time, but the pictures are just as good. It’s an equally good visual metaphor for what’s going on as long as people know where it came from. And so you’ve got the experience of seeing it in the field, working with your group of four or five people, presenting it to a larger group, fielding questions, and reviewing it later, maybe a week or two later or a month later, to see how it fits into how the field developed. Then there can be special topics, like if people are doing insect zoos, where they’re caging plants, putting in combinations of bad bugs, good bugs or bad and good bugs together, and then visiting it every week to see what happens, to see if the bad bug population goes up or if the good bug population wipes out the bad bugs.
Interviewer: Why should farmers do experiments?
PETER: Why it is so important that farmers do experiments is because they get to test what they’ve been told so that it puts them in the position of being the critical peer reviewer of the assertions coming from the trainer. If, for example, the trainer is saying that if you spray the field, you’ll kill the natural enemies and then your field will be more vulnerable to pests coming in later, well, the way you do an experiment is you split some fields in half. Spray one half and not the other half and watch what happens. Keep track of that fundamental hypothesis as you go through. And then you say, well, I’ve got a bug here which I don’t know the name of. Nobody knows the name of. Is it going to eat rice or is it going to eat bugs? So you put it into a cage with rice and bugs and you see what it eats. And you see what is the result. And then, once you’ve determined which kind of bug it is, every time you see it, you can watch its behavior.
You can also do crop physiology. How does a crop respond to being damaged? A number of the experiments involve clipping the leaves off of the plant with scissors or with a knife and watching the recovery. See what happens. See if you take fifty percent of the leaves off a bunch of rice plants when it’s a month old, will the yield of that clump of the field be any different from the yield at the end of the season of a clump where you didn’t cut the leaves off. And if there isn’t any difference, which usually there isn’t, you can begin to own the concept that rice can absorb damage and you don’t need to spray every time you see leaf damage.
Interviewer: What do farmers learn from the experiments, for example an insect zoo?
PETER: The insect zoo experiment is trying to uncover what is the ecological role of a kind of insect. A classic example of insect zoo would have three cages. One of them will be a plant by itself to see how the plant grows. In the second cage, you have a plant plus plant-eating insects, in principal bad guy bugs. In the third cage bad guy bugs and good guy bugs, which are spiders or predacious sucking bugs, in order to see what’s the outcome.
It can be sixty, seventy, centimeters tall, pulled with the mud out of the field, and plunked in a pot. Sometimes we put the cages straight into the mud in the field and mark them off. The point is to get rid of all the bugs first before you cage it. And then put in a measured number of bugs. All this comes from the field. You’re investigating what you find in the field. Then you put in bugs that you are pretty sure are going to eat the plant and you can watch what happens. You may get an idea of what the insect eats. You may also get an idea of how long the insect takes to reproduce, of how long the generation time is. Then add spiders or aggressive assassin bugs that you pick up from the field and eventually you should get some evidence that they eat the bad guy bugs. Then you can start talking about the consequence of good guy bugs eating the bad guy bugs. Bad guy bugs eat plants. If the good guy bugs are together in the field with the bad guy bugs, maybe the plants won’t be hurt as much.
Interviewer: Are participants in Farmer Field Schools doing Science?
PETER: Is science what’s being done in internationally funded research institutions? Yes. That’s where we got the designs for the experiments. But t the question is who’s allowed to do science? If a farmer group does science, is that valid? Our resounding answer is yes.
Whether it is a ten year old sitting in a classroom or if it is a forty year old person standing in a rice paddy, they’re both doing the science. And the empowerment or the ownership and the potential of the eureka experience is exactly the same as if you are a professor at a University. It’s the same experience.
Interviewer: Are you creating better farmers or are you creating scientists?
PETER: We are supporting more powerful farmers because they are learning the language of science and technology. And they’re asking stronger questions in a more sharp-edged fashion. I think that makes better farmers. I think it makes better scientists. And it increases the number of people doing science- it increases the critical community, which, most of the time, I believe can be achieved for science.
Interviewer: Do we need to increase the scientific community?
PETER: Yes. We need lots more scientific thought. We need a lot more citizens. I don’t mean double. I mean a hundred or a thousand times more citizens in global society that use scientific concepts and rules of argument day to day when they look at the technological choices that they’re making. They shouldn’t swallow everything that they’re being given, even if it’s something that I agree with.
We need a thousand people doing science for every one we have now. That’s why science education is essential. That’s why scientific debate doesn’t just mean people with degrees. It means a global civil society that is able to talk about science.
Interviewer: Is there still a need for integrated pest management?
PETER: Well, we’ve only reached two to three million and there’s hundreds of millions of farmers. We’re not even at five percent. Someone once told me that eight percent was a trigger point we had to reach. We’re nowhere near eight percent. It works in some places. And we get groups of farmers having congresses and actually getting both research scientists and government officials to come respond to the farmer congresses. It’s cool that it’s people without any high school that are doing this. They can use the rice field science as an entry point to start that engagement. But in terms of absolute numbers, we got a long way to go. I’d like to see a hundred times more people having at least had the experience of doing science ecology in an environment that they’re managing.
Interviewer: With less pesticide use and continued population increase, is there going to be enough food for people?
PETER: Yes, there’s going to be enough food. Whether they get it or not is a different question. Food production will stay with population. There are still lots of ways that food production is growing. But there are problems. In a lot of places, like in Asia, land is going out of food production because it’s being built into factory land. In a place like Indonesia, the island of Java is a hugely dense place- hundreds and hundreds of people on average per kilometer. And yet we’re losing rice land there because it’s going into factories and an occasional golf course near the cities. Overall food production keeps going up. It doesn’t go up as fast but the overall food production is going up in places like that even with slightly less land and less prime land.
Everyone talks about the challenge of when are we going to hit nine billion people in the world? When it will taper off? There’re going to be choices that have to be made. There’re going to be choices about charging for water.
I don’t see absolute production as being the big issue. It certainly isn’t the issue in food insecurity right now. Food insecurity now has to do with conflict. It has to do with infrastructure of people just having access to markets.
Interviewer: With global population increasing will we at some point have to use more pesticides?
PETER: No, that’s mistaking an input that protects yield with an input that increases yield. That’s the science. Yield is increased when plants photosynthesize more and convert a higher proportion of that photosynthetic energy into available tissue. There’s no pesticide in any of that. By investing in brains instead of chemicals there’s a whole lot more we can do at higher and higher production levels.
It’s easy to make money on selling inputs. But the science has been around for a while and continues to grow higher and higher yields. I think the average rice yield isn’t much more than four tons per hectare right now in the world. And in a number of places, average yield in sub district level areas is six or eight tons without depending on the pesticides. Once you get up to more than double the yields now on an average, some problems may come up. I don’t think they’re insect problems. There may be fungal disease problems that need more thinking, but not insect problems.
Interviewer: Can the global community make a sustainable future for agriculture?
PETER: It’s doing it already. I think it can do better, but, it’s doing it already. People are more conscious of soil. They’re more conscious of the trade offs of using tillage, of plowing versus no till or conservation farming techniques. They can build up ecosystems in soils that deliver nutrient transformation the way good guy bugs deliver pest control services.
Societies can make political choices. We do so much more now, both in terms of moving invasive species around the world and in terms of regulating chemicals than we did forty years ago, even thirty years ago, when I started doing this. The world has said we’re going to get rid of these things. That never happened before. Society can make choices that would have seemed unthinkable thirty years ago.
In Europe, agriculture is much more of a managed landscape that people live in. In the U.S., it’s all somewhere else. People in cities interact not a whole lot with fundamental agriculture. How a society thinks of itself and how that can be informed by science education and by thinking about agriculture as ecosystems is part of that.
Pesticide sales in dollar terms in the world were flat for most of the last ten years. They’ve gone up a bit in the last year or so. Most of that’s herbicides. Insecticide sales are down relatively and absolutely compared to twenty years ago, which is important, because those are the most toxic insecticides. Those are the ones that kill people most and have a lot of side effects on ecosystems. So, in that sense, agriculture is becoming more sustainable already.
7.1 Agriculture Video
Will world population outrun food resources? The "Green Revolution" of the 20th century multiplied crop yields, in part through increasing inputs of pesticides and fertilizers. How can farmers reduce their use of agricultural chemicals and still produce enough food?
Unit 1 Many Planets, One Earth
Astronomers have discovered dozens of planets orbiting other stars, and space probes have explored many parts of our solar system, but so far scientists have only discovered one place in the universe where conditions are suitable for complex life forms: Earth. In this unit, examine the unique characteristics that make our planet habitable and learn how these conditions were created.
unit 2 Atmosphere
The atmosphere is what makes the Earth habitable. Heat-trapping gases allow ecosystems to flourish. While the NOAA Global Monitoring Project documents the fluctuations in greenhouse gases worldwide, MIT's Kerry Emanuel looks at the role of hurricanes in regulating global climate.
Unit 3 Oceans
Oceans cover three-quarters of the Earth's surface, but many parts of the deep oceans have yet to be explored. Learn about the large-scale ocean circulation patterns that help to regulate temperatures and weather patterns on land, and the microscopic marine organisms that form the base of marine food webs.
Unit 4 Ecosystems
Why are there so many living organisms on Earth, and so many different species? How do the characteristics of the nonliving environment, such as soil quality and water salinity, help determine which organisms thrive in particular areas? These questions are central to the study of ecosystems—communities of living organisms in particular places and the chemical and physical factors that influence them. Learn how scientists study ecosystems to predict how they may change over time and respond to human impacts.
Unit 5 Human Population Dynamics
What factors influence human population growth trends most strongly, and how does population growth or decline impact the environment? Does urbanization threaten our quality of life or offer a pathway to better living conditions? What are the social implications of an aging world population? Discover how demographers approach these questions through the study of human population dynamics.
Unit 6 Risk, Exposure, and Health
We are exposed to numerous chemicals every day from environmental sources such as air and water pollution, pesticides, cleaning products, and food additives. Some of these chemicals are threats to human health, but tracing exposures and determining what levels of risk they pose is a painstaking process. How do harmful substances enter the body, and how do they damage cells? Learn how dangers are assessed, what kind of regulations we use to reduce exposures, and how we manage associated human health risks.
Unit 7 Agriculture
Demographers project that Earth's population will peak during the 21st century at approximately ten billion people. But the amount of new cultivable land that can be brought under production is limited. In many nations, the need to feed a growing population is spurring an intensification of agriculture—finding ways to grow higher yields of food, fuel, and fiber from a given amount of land, water, and labor. This unit describes the physical and environmental factors that limit crop growth and discusses ways of minimizing agriculture's extensive environmental impacts.
unit 8 Water Resources
Earth's water resources, including rivers, lakes, oceans, and underground aquifers, are under stress in many regions. Humans need water for drinking, sanitation, agriculture, and industry; and contaminated water can spread illnesses and disease vectors, so clean water is both an environmental and a public health issue. In this unit, learn how water is distributed around the globe; how it cycles among the oceans, atmosphere, and land; and how human activities are affecting our finite supply of usable water.
unit 9 Biodiversity Decline
Living species on Earth may number anywhere from 5 million to 50 million or more. Although we have yet to identify and describe most of these life forms, we know that many are endangered today by development, pollution, over-harvesting, and other threats. Earth has experienced mass extinctions in the past due to natural causes, but the factors reducing biodiversity today increasingly stem from human activities. In this unit we see how scientists measure biodiversity, how it benefits our species, and what trends might cause Earth's next mass extinction.
unit 10 Energy Challenges
Global energy use increases by the day. Polluting the atmosphere with ever more carbon dioxide is not a viable solution for our future energy needs. Can new technologies such as carbon sequestration and ethanol production help provide the energy we need without pushing the concentrations of CO2 to dangerous levels?
Unit 11 Atmospheric Pollution
Many forms of atmospheric pollution affect human health and the environment at levels from local to global. These contaminants are emitted from diverse sources, and some of them react together to form new compounds in the air. Industrialized nations have made important progress toward controlling some pollutants in recent decades, but air quality is much worse in many developing countries, and global circulation patterns can transport some types of pollution rapidly around the world. In this unit, discover the basic chemistry of atmospheric pollution and learn which human activities have the greatest impacts on air quality.
Unit 12 Earth’s Changing Climate
Earth's climate is a sensitive system that is subject to dramatic shifts over varying time scales. Today human activities are altering the climate system by increasing concentrations of heat-trapping greenhouse gases in the atmosphere, which raises global temperatures. In this unit, examine the science behind global climate change and explore its potential impacts on natural ecosystems and human societies.
Unit 13 Looking Forward: Our Global Experiment
Emerging technologies offer potential solutions to environmental problems. Over the long-term, human ingenuity may ensure the survival not only of our own species but of the complex ecosystems that enhance the quality of human life. In this unit, examine the wide range of efforts now underway to mitigate the worst effects of man-made environmental change, looking toward those that will have a positive impact on the future of our habitable planet.