Focus 580; Nitrogen Pollution In North America

In this hour of the show the second hour of the program we'll be talking about nitrogen pollution and particularly concentrating on North America. Our ability to take nitrogen and put it into a form that can be readily used by plants has certainly been a good thing for agriculture in many ways and it has increased agricultural production but now it seems that there are those growing number of scientists who are concerned about pollution that is too much nitrogen both in the air and in the water and the possibility that it could have some negative effects on human health. We'll try to explore the basic issues this morning in this part of the program as we talk with Robert Howard. He is David Atkinson professor of ecology and environmental biology at Cornell University and is here visiting the campus to Doc about this very subject with people here in Champaign Urbana is good enough to come and spend some time with us. And as we talk questions are certainly welcome people who are listening I can call and ask your own question. The number here in Champaign Urbana 3 3 3 9 4 5 5. We do also have a toll free line that is good anywhere that you can hear us and that is 800

to 2 2 9 4 5 5 so any point here if you have questions please do pick up a telephone and a call. And thank you very much for for being with us. Thank you. Please be here. Nitrogen obviously is a naturally occurring element. It's in the air and it's a basic sort of constituent of the natural world. But I guess that what we're talking about here though is an increase in nitrogen as a result of human activity. One way or another and I guess basically on one source would be burning fossil fuels and the other would be what we have done to make it as I said something that's useful as a fertilizer in there we can put on plants and both of those ways apparently we have added greatly to the amount of nitrogen that's out there and I gather that relatively recently within say the last 10 15 years there's been a very large. Very large growth in the amount of nitrogen we're we're putting out.

Yeah that's exactly right and nitrogen is critical to all life that's critical to agriculture it's a good thing it's a nutrient in the natural world. Ninety nine point ninety nine percent of the nitrogen on earth is the molecular nitrogen that surrounds us in the atmosphere and it's dissolved in the oceans and it's it's availability to the organisms is very low the bacteria can catalyze this reaction and make it available but it's a slow process globally. Humans have managed to duplicate that process and we've had the scientific know how to do that for maybe in less than 100 years really hasn't caught on as an industrial technology until after World War Two and it's Excel rated since then so. So as you say there are two things going on One is that when we burn fossil fuels we inadvertently take some of this molecular n2 around us and make it reactive biologically available that's a mistake. The other thing is purposefully creating fertilizer synthetic nitrogen fertilizer and you know I think we have to say that's a good thing that the

population we have on Earth today starvation will be massive if we didn't have that technology supporting agriculture. Did you have to view as a good thing but. We've done that quite recently and we've done so without full realisation of what the consequences are. I mean that as you mentioned a lot of this has happened the last 10 to 15 years. Half of all of the synthetic nitrogen fertilizer that's ever been used on Earth has been used in the last 15 years. That's a really a mark of a statistic I believe that came out of your research some research that you were in one solve it it's using data from the United Nations if you Negra Cultural Organization program in the United States you know we started using synthetic nitrogen fertilizer a little bit in the 60s it really took off in the 1970s. But the rates been going up a little bit since then but now we've moved at a moderately stable situation for the last 20 years or so but you look at developing countries India and China and their use of fertilizer has just exploded in the last five to 10 years. Well I guess we have sort of two major issues or two major

avenues ways that it gets in the environment. On the one hand we have automobiles and I guess Liquor City generating plants that are burning fossil fuels and so it gets into the air and breathing it and causes certain kinds of consequences. Then the other issue the main issue I suppose is the fertilizer that we put on we put it on farm fields. We also put it on golf courses. People put it on their lawns and that runs off and eventually that ends up getting into water into groundwater into rivers streams lakes and the oceans. Taking out that first part first. How if you look at the total amount of nitrogen that that we have through human activity put into the environment how significant is the air component. It's if you look at the global alteration of the nitrogen cycle what we're doing in agriculture is a bigger and bigger flux. Globally

three quarters 80 percent of the of the increased nitrogen supplies associate with agriculture and only 20 25 percent with this fossil fuel source. But that varies a lot regionally. Nitrogen is reactive stuff in these forms. So you see a lot of regional variation across the globe across the continent. So in the Northeast United States where I live the atmospheric components by far the biggest source of fossil fuels are the biggest problem here in the Midwest you know agriculture is definitely the biggest problem and the biggest source. Well let's talk about that a little bit more since that is I'm sure that there are people who are listening who are involved in agriculture and here that's a prime concern of people at the university. So those are the main If we're looking at where the biggest source is it is going to be from nitrogen fertilizer that is deliberately put put on the ground again. It's not just agriculture. There are there are these other cases because I do put it on their lawns and. They put out golf courses and things like that. You

know they're there it's no we can't. It's not all farmers fault. And I'm sure that farmers like to point out the fact that yeah maybe they're doing it but they're not and they're not the only source. So when you look at all all of those things. How significant is each of those components as a contributor. Well it really I mean you're correct fertilizers used in all sorts of places in golf courses and homeowners grossly over fertilised compared to what farmers do. But still a lot of farmland out there and farmland is where most of the fertilizers used. Ninety five percent of it say here in the Mississippi River basin. You know overall I think I don't want to lay the blame on farmers but I really do believe that the use of synthetic nitrogen fertilizer has a allowed a level food production that made the earth a better place to live overall. But. Farmers could do a lot more to reduce the loss of nitrogen off of their fields. And you know some of them are beginning to understand that more and I think we're

moving in a direction that is encouraging. Farmers are bright people and they but they're of the prime motive is to return to profit off of their farms. Secondarily many of them do care about environmental issues. I think the real key here is to is to better educate the farmers on how they can maintain their productivity while also helping with this environmental issue. And there are all sorts of things they can do that the beginning to do. Well how much how much could you do simply by applying less. And could you get the see you could you get the same FACT that thing that you're looking for and at the same time apply less which I'm sure also farmers would would say well that's a good thing because the less I have to less I have to buy them some money and save some money because that's a good that's a big cost of production. Yeah exactly. You know farmers vary a lot. The farm to farm use of fertilizers very variable but if you look at the statistics overall for the average farmer in the upper Midwest here particular during the

1990s farmers use more fertilizer than is even in their economic interest. They if they use less fertilizer and save some of that the cost of the extra fertilizer their yield really wouldn't have suffered they would have earned a higher profit. They've started to realize that they're using less fertilizer now than they would have been five or ten years ago. I think the data suggest they could use less fertilizer yet and still maintain an excellent yield and there are some innovative programs that are moving them in that direction. Part of the problem is that you know farmers are risk averse. They live in a business where the profit margin is small. They have a tremendous amount of capital invest in their land and equipment. They really need that they can't afford to take risks with with their investment and so they they tend to use fertilizer at moderately higher rates higher than research suggests is necessary just in case they have that perfect growing year where they get a great crop if they use that extra

fertilizer they want make sure they maximize their profit. There's a there's there are some efforts and I'd highlight one which is the American farmland trust is set up. It's a experimental program nonprofit non-governmental organization is essentially set up an insurance pool to take the risk out of having farmers use less fertilizer. So farmers join this program. They use less fertilizer. They save money by using less fertilizer and they take some of that savings and they invest it in the nonprofit fund insurance pool basically. And then on their fields they have some test strips of land which are heavily fertilized very heavily fertilized. And at the end of the growing season one goes out and compares the productivity on the land as a whole with what it is in the very heavily fertilized trips if in fact their productivity is lower on the average lamb because they've used less fertilizer than this fund reimburse them the cost of the last year

otherwise the fund keeps the funds and keeps accumulating. Either way the farmer saves money in less fertilizers used. And what we're finding is that indeed the fund very seldom pays out because the farmers have been over fertilizing. But this allows them to see so in a way that. There is no economic risk to them. Our guest in this part of focus 580 is Robert Howard. He's professor of ecology and environmental biology at Cornell University and he's visiting the campus of the University of Illinois Urbana-Champaign we're talking about nitrogen pollution questions are welcome 3 3 3 9 4 5 5. That's for champagne or been a Folks we do also have a toll free line that is good anywhere that you can hear us 800 to 2 2 9 4 5 5 we do have a caller over by Danville in Belgium nearby and line number four. Hello good morning sir. I'd like to explore fertilisation itself and that is

you know people one in town spading know fertilizer is just what they sprinkle in their yard as is its granules and it incorporates itself into the yard or in the garden and fertilizes the animals that the farming the plants. However the way it's done in agriculture is it's injected as money like ammonium hydroxide you know ammonium money my drugs but I'm only I'm guessing way and it's plowed into the ground fairly deeply and owned it. Done. Oh not quite now but maybe a moment from months from now when it's all a bit colder. Now it seems that there's been a great deal more lost because of it's being injected into the ground and exasperate into the air and just generally dissipate much quicker because of the cast structure. Why hasn't there been some technology to move in a different direction and thereby also reducing the amount of nitrogen that's placed on the ground and subsequently less loss going down the

Mississippi River in the Gulf of Mexico. Well that's a good question and there is a there is a tremendous amount of research on how to better use nitrogen fertilizer. A lot of it's done on this campus and a lot of other other campuses across the country in fact there's a lot of complexity behind it. You referred to the ammonia use in the hydrous ammonia is a major fertiliser use less so now than would have been through 10 15 years or so ago. And in fact the deep injection of the ammonia helps if you surface supply the ammonia you lose more to the atmosphere so the technology that you refer to for deep injecting there actually is more effective at keeping it in the soil. That's an improvement that was made whole probably in the late 1980s early 1990s that the latest trend in fertilizer use at least nationally I'm not sure but locally here but on average in the upper Midwest. Is towards using your Rio. And Yuri is an organic nitrogen form but again it's made

synthetically using fossil fuels. And it's it has its home with its advantages to the farmers it's easier to handle it's not as if it's explosive or toxic. It weighs less than say nitrate forms as a fertilizer so it's cheaper to move around. But it has its own set of problems and a lot of it can valise off to the atmosphere. A lot of it can leach directly to surface waters where was some recent evidence suggesting it more than average fertilizers might perpetuate harmful algal blooms. So there are problems associated with that use. I think there's a lot you mentioned also in your question that farmers maybe in the next month will get out and start spreading the fertilizer. They do that because the ground firmed up it's frozen seas yet the tractors out there they have time on their hands. But there's plenty of research showing that when you fertilize in the fall or winter in the sort of climate you lose a lot of that fertilizer in the spring runoff period and that you're if you can handle it

you're more effectively using the fertilizer. If you apply it in the spring or during the summer much much better for the environment. I think oh I have another question just faded. Mike thanks very much for the well other questions are welcome. 3 3 3 9 4 5 5 here in Champaign Urbana toll free 800 to 2 2 9 4 5 5 and again our guest Robert Howard. He's professor of ecology environmental biology at Cornell University. Perhaps I should give you the opportunity to talk a bit more about the environmental impact of this nitrogen because we've sort of passed over sort of took it for granted the fact that it's a problem particularly when it gets into the way that we're talking about runoff that ends up in streams rivers in coastal waters. How is it that is a problem. Well the coastal problem is really a major problem globally now but also in the United States that this nitrogen that runs off much of it

does reach reach coastal waters there it acts like a fertilizer and it stimulates algal growth and we end up with excessive amounts of growth which are the most obvious effect of that is when the material dies it consumes oxygen in the in the water and we have all sorts of ecological damage from that. The more subtle effects to lose sea grass habitat. We have subtle ecological changes alteration in the food webs which are deleterious for the sort of things we care about fish and fisheries. Here in the United States we believe that two thirds of our coastal rivers and bays are now either moderately or severely degraded from this nitrogen pollution. So that is probably the biggest pollution problem facing the oceans at least in the United States perspective. There's less data on that in many parts of the world outside the United States but the United Nations environmental program issued a report last spring saying that this nitrogen coastal pollution is perhaps one of three or four greatest global environmental challenges facing the Earth as a whole.

I saw it and it's not just a problem in the United States a problem all over. That's correct. And creasing Li as we see synthetic fertilizer used more in the developing world. It's good I mean. It's good for the people of China and India. Starvation is way down the diet and health is improved. There's no doubt about that. But we need to all to be cognizant of the environmental consequences of that in those countries too are beginning to realize that they're beginning to try to grapple with how and balance of these. And as as we said before there can be there can be a variety of sources. And there has I think been some controversy about the the contribution of Agriculture and I suppose depending upon where it is you're talking about. You could be talking about different sources but at least here if we talk about the Midwest and particularly the concerns of a lot of people have voiced now for a number of years about what's happening in the Gulf of Mexico for example there there we seem to get into some arguments about well OK who is responsible what is primary responsible there is it

as far as you're concerned is it pretty clear that really what we are talking about here is run off from farm fields and agriculture is that it. Absolutely in this area. I mean let me preface my response by saying that I think in some parts of the country in some parts of the world it isn't clear at all. If you look at Chesapeake Bay which has a terrible problem of nitrogen pollution the scientific evidence on sources is very confused. There are several different contradictory studies and I don't think we have a good handle on what's going on and just be. On the other hand for the Mississippi River and the Gulf of Mexico situation. There's a large body of science several diverse types of information brought to bear all of which show pretty conclusively that the hypoxia is caused by nitrogen in the nitrogen is coming from the upper Midwest predominately agricultural sources at least 70 percent of it from their cultural sources. I really think that's beyond question at this point. Is this something that's reversible.

Yes I believe it's reversible. The time between the use of fertilizer and it's running down the rivers. There are huge lags associated with that mean that the best the best study of the reversibility we have is an inadvertent experiment with the collapse of the Soviet Union agriculture. Basically disappeared from Eastern Europe in a very short period of time. So it you know was subsidizing that era with synthetic fertilizer that source went away hasn't really been replenished. Now as of the late 1980s the Black Sea which is a coastal water body downstream of that area and by the Danube looks at her was suffering exactly the same sort of problems that we see in the Gulf of Mexico a large deterioration of water quality that occurred over about a 15 or 20 year period leading up to that with the collapse of synthetic fertilizer use of the Black Sea started to recover within three to four years and have been covered markedly it's its health now would. Be similar to what was

40 40 years ago. Prior to that he's a synthetic fertilizer so that that tells us that at least at that landscape the recovery is fairly rapid I think we know enough to suggest that would all to be true in the Mississippi. Maybe we talk a bit more about what exists and what we have seen happening in the Gulf of Mexico because people really aren't or have not followed the story and are really really sure about what the effect has been. You know they may have heard about this they may have heard the term like hypoxia or they may have tired but stuck by dead zones. But may not exactly sure what is it what is it depends on you know what is it that you are talking about. The problem is one of excess nitrogen stimulating excess phytoplankton growth of the microscopic algae living up in the water column of the mouth of the Mississippi River. The currents in the Gulf of Mexico move this water along the continental shelf along the Louisiana shelf to the to the west. And as they get a large increase in the growth of phytoplankton there as it dies off and sinks

into the bottom water the oxygen levels are diminished. That's what we call hypoxia. We're looking at concentrations of oxygen that might be. A quarter of what they would normally be. And that starts to put a large stress on the animal community that would live in the area in extreme advance. The oxygen will actually go to zero. Of course that's deadly to lots of things. The Dead Zone isn't isn't dead in that organisms don't live and in some ways it's a it's a misnomer because what we have is too much phytoplankton life. But it's a it's a diminishment in the sort of animal life that society values and it's covered a fairly large area the best work on those by Nancy rebeling from Lousiana University Marine Consortium and she and colleagues have shown that they've tracked this now over several years. Some areas the the hypoxic area the low oxygen areas much larger than others. I think we know of an excellent understanding from her work and from people that know is like Dawn's

KVOA. Can very accurately predict what the area will be based on the climate in the Mississippi. How much nitrogen. What years brings more of this fertilizer down than dry years. So we see year to year variation in the in the pox examine associated with that and also storm events in the Gulf of Mexico hurricanes are a good thing and they break up the the water column and replenish the oxygen and can can change that. But there's a general trend towards Assyria getting larger over time subject to this in renewal variability due to storms and climate. Yeah and so you're what you're having is over stimulation of growth of organisms that would be that have been there anyway. That's right there would be a normal part of the ecosystem. It's just that by pouring all this and this nutrient in there you're you're overstimulating one sort of component. Yeah that's right were overstimulating them resulting in more growth than those overall healthy for the for the community and you're also in that you're selecting for different types of algae and you're selecting for things that are probably not as good for the ecological structure that would lead to

say the fisheries. Yeah and that really is the bottom line with the the problem has been or it has been a problem for commercial fishing because now this means that if you're going to if you're going to fish you've just got to go further and further out. You have to go further on that. That's correct yeah. We have another caller here let's talk with them in Urbana. Lie number one. Well yeah you know in terms of Smaug what the impact on you. And it is you know it is growing more and more evidence there. What about the impact on humans and this one you know direct impact in terms of problems that you know individuals can have. Well in terms of the coastal water quality I think we're largely talking about degradation of environmental quality loss of fishery resources and of course that has indirect effects on health but not a direct health effect. There is no direct health effect. No there is because associated with this. We're also seeing increased incidences in occurrences of what we call increased duration of what we call harmful algal blooms and these are these are specific types

of algae that produce talke substances. They're naturally occurring organisms they've been around you can read about blooms of these things in the Bible so we know they've been around for for millennia. But we also have good evidence at this point that the length of these blooms and where they're occurring is increasing and it seems to be stimulated by nitrogen pollution so these are things which are produced talks and that might accumulate in shellfish and can cause human. Poisoning sometimes death sometimes paralysis more commonly diarrheal sort of things. There is also some evidence that this coastal nutrient pollution. Can increase the occurrence of vector borne diseases like cholera. We don't see it the United States but in developing countries where color is already present when we degrade the coastal water quality the color bacterium is longer lived it seems to be carried along with these blooms and we see increased diseases of that

sort. More broadly I mean nitrogen isn't just degrading these coastal waters it's. It is contaminating the atmosphere and you mentioned smog. I mean the odes on pollution is a big big public health problem the American Lung Association. Estimates that there are thirty thousand premature deaths of Americans each year from ozone pollution in the air. That ozone pollution is caused by nitrogen pollution coming from fossil fuel sources. So I understand what the Midwest is is one of the. Concentration right in terms of nitrogen they create. So if the atmospheric sources Well not in terms of ground. Yeah in terms of groundwater it's very high. And the another another issue is nitrate in drinking water and there are all sorts of health risks associated with that. One of which is what we call blue baby syndrome. Just the hemoglobin in babies is tied up by the nitrate and isn't as effective in moving

oxygen through some of the health risks. But but nitrate in groundwater also poses a cancer risk and can increase other diseases as well. Thank you. I think also I think one of the things that I read about it was that increased nitrogen in water somehow makes it more hospitable to mosquitoes and that it's actually good for them and their breeding and of course that leads to concern because we have mosquito borne diseases like encephalitis and West Nile and more mosquitoes. Theoretically that could mean more disease. You know you're referring to a paper that Ellen Townsend the University of Colorado let a group on a year or so ago and he basically got a bunch of medical scientists and ecologists and all to think as creatively as we could about what nitrogen what this human alteration of the nitrogen cycle means for health. The mosquito aspect is one part of it because of course there are a variety of different mosquitoes carry diseases and they

vary a lot in their ecological responses to the environment. Some of those species definitely are encouraged by water flow or water quality. The one that carries West Nile fever is clearly associated with that and so we we do believe that nitrogen pollution could contribute to West Nile fever spread from malaria it's more complicated because there are many different species of mosquitoes and involved and some of them like dirty water and some of them like clean water and that's what we tried to call for is more of a Science Challenge to think more broadly about this issue that people have. But let me mention one other health intervention which which came out of that same report by Alan Thompson and that refers to allergies and. We we know that allergies are way up in the United States over what they were a few decades ago in their variety of reasons that might be true. There's a tremendous My debate in the medical literature about that. But one of the things we also know is that there's a lot more pollen in the atmosphere than there used to be and a lot of the pollen that people are allergic to ragweed things of that sort are

weeds that are highly responsive to nitrogen fertilization. You fertilize ragweed and you increase its growth a little bit but you increase its pollen production incredibly because that's what it means to be a weed you throw out more material as you try to reproduce and spread yourself around. So we believe that's at least plausible hypothesis that this increase in nitrogen flux through the atmosphere is responsible for the increased pollen in the at least part of the epidemic of allergies that we see in the United States. We have someone else to talk with. This is again. Urbana and urban a listener line to you. Hello. Yeah it's good to hear your issue being discussed because the same issues that where there's a direct cargo war between both economy and pollution a fact including in public. Eco systems disruption are often difficult to

get on locally so this is really great. I have a quick question and I've got to hang up and listen to you on the air. But I understood that the Netherlands and Europe was also a big hotspot for nitrogen nitrogen pollution and if that's so I was wondering if you if you knew anything about the way they were handling that between the Netherlands and the surrounding countries and all I'm going to have to hang up and listen thanks OK. Thanks for the call. That's an excellent question. You know Little is indeed a hot spot of nitrogen pollution. They have a credible dense population there. Most of their nitrogen problem is from agriculture. And there it's largely an animal agricultural issue they have tremendous populations of farm animals pigs but multiple tree and other

other things and tremendous amounts of nitrogen waste associated with that in a way they're a microcosm for parts of what's going on the United States here here in the United States. We grow corn soybeans here in the Midwest and we ship it to poultry farms in Maryland and hog farms in North Carolina. And you end up with a tremendous amount of animal concentration waste in those areas which is very problematic very polluting. You know if you go back 30 or 40 years those animal waste would have been returned to the field in a systematic way and reused as fertilizer. The large use of synthetic fertilizer has allowed us to break that chain that's it's cheaper to buy synthetic fertilizer than it is to move manure back to Illinois from from North Carolina. What we're seeing in the Netherlands is that they import grains from all over the place import from the United States but also from many other countries and they use that to support these really massive animal populations. And then they have

this tremendous amount of waste that they use in their local farms but it's an excess by you know huge amounts over what the crop needs there really are. They've taken they actually as opposed to what we do in the United States here. They've moved into a regulatory framework where they determine how much nitrogen a farm can actually use they've set limits on the total mass of nitrogen allowed on a farm on a per area per time basis. And they're trying to regulate it that way what they call a nitrogen management plan but with a regulatory framework behind it. They have something to excess things I think are moving in the right direction but but slowly. The consensus of their scientists now is that meeting discussing this just a few weeks ago is that they are nowhere near where they need to be there yet they have total nitrogen inputs to the farm fields that are in the neighborhood of 250 to 300 pounds per acre whereas a farmer here

in the upper Midwest might be using in terms of synthetic fertilizer maybe one hundred seven hundred eighty pounds per acre which which I still think is too much but that they're almost twice as high as that another one so they've a long way to go yet. Right. Another caller again Urbana line 1. Hello hello. Yes I was wondering if the incident third a problem with agricultural runoff with nitrogen. And couldn't in part be mitigated as part of a kind of a larger ecological problem a lack of green space and farming right adjacent to waterways. And if the runoff from nitrogen might in fact be mitigated if there were green spaces allowed for natural absorption of the nitrogen before it reached waterways I'll hang up and listen to your answer. That's another excellent question. This is the little complexity behind my answer. There are tremendous number of things farmers can do to

reduce the problem in addition to using less fertilizer in one. Let me just before I get onto your answers to is to move into different cropping systems they may be used perennial crops instead of corn or soybean. So that during the spring time when nutrient levels are often very high in soils there are meats available to take up the nutrients or let them run off if the farmer doesn't want to do that than planting winter cover crops is a huge help again. So there's living biomass out there to absorb those nutrients in the spring. The green belt idea the idea of having a buffer between the field and the waterways is a good one. It's it's somewhat effective subject to a constraint if you put a drainage ditch drain tile from your field and have that under law and go underneath the greenbelt right to the creek. Then the greenbelt looks nice but is you know effective at controlling the nitrogen flux and then a lot of cases that's what we've done in you know. Case in point in just big bay area the

state governments of been trying pretty hard since the might mid-1980s to reduce nitrogen pollution. Green belts are one of their major mechanisms for doing that but they they paid insufficient attention to whether the the green belts were really intercepting the groundwater flow of nutrients from the field or not. And we we now know that they need to pay more attention to that. Of course in a flat terrain like this if you if you don't have those drain tile underlying it then you have a hard time getting the water off of the field and the farmers will tell you it will really trash their productivity. We have about 15 minutes left in this part of focus 580 Our guest is Robert our thesis David R. Atkinson professor of ecology and environmental biology at Cornell University we're talking about nitrogen pollution how questions are welcome again 3 3 3 9 4 5 5 toll free 800 to 2 2 9 4 5. We're certainly getting into the area that I wanted to make sure that we hit and that is what is it that we can do to reduce the problem. And that fortunately there are some things that can be

done and we talked about things that generally things that farmers can do to starting out to use less and realize there and then also make sure that they lose a lass that is whatever they put on actually gets used to get steaks up taken up by the plants so that it doesn't end up just running off. Can you talk a bit more about some of the kind of advice that farmers are getting about addressing a problem in both those ways. I'm not entirely sure how effective we are yet communicating this directly to the foreign community. I think we are just beginning to get there. But the farmers receive their information in a variety of ways and I don't think they're hearing the message in a consistent voice if you will. The economic extension agents might be giving one set of advice but the Farm Bureau is probably speaking with another voice they haven't yet acknowledged. This is a problem and then they try to argue in fact that it's not. So I think we have a way to go in giving the farmer consistent information. But to me as a

as a scientist is you know worked on this issue for 25 years. The biggest frustration is that the the the need to do something is never been more clear this is a major environmental problem. And we do have technical solutions technical solutions are there for agriculture they're there for the automotive sources and industrial sources. What we lack is a good political leadership and good policy framework for moving ahead. And that's that's been frustrating. On the other hand I think we're making progress. In any event just from the ground swell up if you will I mentioned earlier that the American farmland trust which is an NGO has taken this innovative step of setting up a nonprofit insurance program to to encourage farmers to use less fertilizer. I think that sort of thing is likely be effective it's in the farmers economic interest as well as the good for environmental quality to do that sort of things I think where we're moving the right direction if slowly.

Another caller here Bloomington Indiana our toll free line line for Hello. Hi how to sewerage treatment plants. Prevent sewerage affluent so affluent from causing nitrogen pollution. OK good. Good question. I haven't mentioned sewage in some areas sewage is actually the largest source of nitrogen in the state of New York where I work now. Hudson river estuary the biggest problem the sewage that would be to of Long Island Sound as well. There's a paradoxical problem there. It's historically sewage you pulled a sewage together and in much of the United States until the 150 160 we didn't treat sewage all we we called it primary treatment but it really meant no treatment at all most everywhere in the country. By the 1980s or 90s receive what we called secondary treatment. And that's really designed to remove the organic matter out of sewage sludge you know putting on a big oxygen Lowden in the sea water bodies. It was not designed it was not intended

to do anything at all for nutrients. It does take a little bit of nitrogen and phosphorous takes about 15 percent of the total flow of both nitrogen and phosphorus out of the waste stream. But paradoxically by improving the immediate water quality downstream of a sewage treatment plant within a mile or so of the plant a lot of the nitrogen that's discharge from the plant ends up going further you're diminishing what the natural bacteria are doing right outside of the plant. And so in some cases we've seen examples where the downstream nitrogen pollution got worse after we just went to secondary treatment plants there. So we still have a problem. Oh yeah. And then there are technologies there we call them nutrient reduction technologies or maybe tertiary treatment technologies for nitrogen that the trick is to try and convert it back to into gas in which case it's no longer a problem. Technology's there for a large city it's moderately expensive it costs a round of five to 10 cents

per person on a sewage treatment plant per year in a sustained way to treat nitrogen which doesn't sound like much but get it up for a city like New York and you know you're talking big money all of us and thank you. Very much I mean things. Well this again points to the fact that it's it is a complicated problem and depending upon geographically where you're talking about the source of the problem can be something different as you have said you think that for example if you're talking about the Gulf of Mexico the primary problem is runoff from from farm fields. There may be other places in coastal areas where the problem is large livestock operations and then there may be other places where the problem are big cities that are on the coasts like New York City and and you see at other places and I'm sure you see at other places around the world and there it's basically the problem is the waste it's produced by human beings and large concentrations of human beings. So it's a different you know the point source is is different depending upon where it is that you're talking about. And then you throw in the fossil fuel atmosphere transport source of the deposition of this acid

rain containing nitrogen it's another problem. And what they have in common is that in the receding waters they'll cause the same same problem and we're seeing growth in it from all of these sources does. How much of a problem is that I guess when we were talking before about the problem of atmospheric pollution and and when you talk about its effect on human health I guess there were I'm thinking about it from the fact that people are burned it has an impact on the air quality and the air that people breathe. But again if you go to environmental issues how how how big a problem is it. Deposition through rainfall that it gets a burning fossil fuel gets up into the environment but then it also it comes back down the effect of rain and then again you end up that ends up getting in surface water and and the groundwater does that add a lot to the to the total problem.

It can in some regions that that deposition on of the landscape with subsequent transport of the nitrogen downstream can be the largest source of nitrogen to coastal waters. I mentioned earlier that we have a big debate in the scientific community about what's really going on Chesapeake Bay in terms of the sources what one of those debates is homeport and atmospheric deposition is some of us think it's the primary source of nitrogen to Chesapeake Bay. Other people disagree with that. My own science tends to say it's very high but there are you know there are problems with all of our science including mine and in that area. And so we don't entirely know it's a hot area of research. Nitrogen deposition has other ecological effects it's the United States has done a better job of controlling self your gas and you know acid rain over the last two decades but we haven't done such a good job with controlling nitrogen and nitric acid and so at this point acid rain in the United States is increasing the nitrogen problem it's a bigger problem than the sulfur pollution and beyond just

acidifying lakes and streams and controlling us by tradin downstream to coastal systems. The nitrogen can have an effect on forests and on the terrestrial landscape and there's some very convincing studies recently out of Europe showing that where atmospheric deposition is high the bio diversity of the landscape is decreasing has decreased remarkably over the last two decades and there's some new evidence out of Canada suggesting that forest product of WITI in Eastern Ontario is going down as a result of nitrogen deposition onto the forested landscape. Let's talk again with another caller this is someone in Champaign That's line one. Hello. Yes. I'm listening but I wondered if you might say. Something about the excess use of not you don't want seems to be a fairly massive problem someplace. Yeah I mentioned that just briefly early on homeowners who fertilize tend to massively over fertilizer at the

homeowners aren't as conscientious as farmers really in and not as cost conscious either. She shipped out of it in localized areas that could be a big problem if you take a coastal area like Cape Cod Massachusetts with really sandy soils and lots of green lawns that's a big part of the problem but in general in a large area here like the Mississippi it's a tiny fraction of the nitrogen compared what agriculture is doing. They must think you and again we have about five minutes left. Someone wants to call with questions I want to go real quick. We can get him in 3 3 3 9 4 5 5 toll free 800 2 2 2 9 4 5 5. Because I'm a little interested in an earlier comment you made and I know have want to get too political in the conversation but I guess that I wonder about cases where arguments like this or discussions like this do become politicized and that certain positions become associated with certain political persuasions and that that

somehow makes sometimes the discussion difficult because you know one one side ends up being labeled sort of the liberal way of looking at things and one side is the conservative way of looking at things. And it seems that it would be it would be more productive in a scientific sort of sense if we just toss that stuff aside and just look at it more straight forward kind of discussion about OK what's the problem. What are the sources what do we do about it I mean is this in case in which you think politics is actually getting in the way of our understanding what's going on and then moving toward a solution. You know actually I don't I don't think politics has gotten way very I made a comment about the failure or the lack of political leadership but it's not easy. I think it's been a bipartisan good. I don't think this topic is on the radar screen of most politicians of any political persuasion. It's surprising to me because you talk to the scientific community who study it and we all do

believe it's a major problem compared to many other environmental issues which are discussed with much more prominence in the press or politically. But it might be because of the complexity of sources and the complexity of issues it's also a problem which is still relatively recent It's these issues of just cropped up in the last few decades and you know maybe it takes that long for science to sink into the public consciousness. Well it's interesting you know and given given the amount of attention for example the just devoted to it an issue like global climate change. Which is also complex. It's sort of surprising that then this that seems to be equally important and you can demonstrate that it has effects on human health hasn't got the amount of attention. Maybe that's a media issue that for some reason that the news media just hasn't grabbed on to that the way that they have grabbed on to the other. I think it takes time. I mean I remember first hearing about global climate change when I was an undergraduate student in my early days of graduate school back in the early 1970s

and there were plenty of scientists then talking about global change as an issue. It certainly wasn't in the media at that time it took a few decades for it to come around. This nitrogen issue really has developed since then you know this is an issue that has come into its own in terms of the problems during the 1980s and 1990s. It is a global change issue it's the result of humans changing the face of the earth very very quickly in some ways what we're doing with nitrogen is much more rapid rate of change than what we're seeing with climate or carbon dioxide in the atmosphere. But precisely because it's so rapid and relatively new I think is a long lead time here before it's complex science sinks into the public consciousness trying to Norm or call or hear someone on another person listening this morning in Bloomington Indiana our line for Hello. Good morning. Yes I need a recommendation of a book. Will science that you think would be helpful a political tool. Layman homeowners who have not read the

Nature and property of soils by Foxman and Brady don't have access to the 57 year book of Agriculture the book on the photo. Can you think of something or not off the top my head and then. True confessions I'm a I'm an oceanographer by training so I talk a little bit about agriculture here I'm not a soil scientist. I will say though that the University of Illinois here has some excellent people and it has some very well informed nitrogen experts in the department its resources in particular I'd refer you to them. OK surely over there in Bloomington somebody that the university there or maybe up at Purdue would be able to answer that question right. There's also an excellent book by a backless mill which came out I think in 2003 called enriching the earth and sort of the history of change in nitrogen over the last century fascinating reading and a great introduction to the general topic. Well David I did take the agronomy courses at Purdue but I was left with this challenge of introducing this whole complex to Reno soil science

to homeowners here in Bloomington. And I realize that very few people were going to take. It's time to go to Purdue or read the Nature and Property Book of oil by blocking and Brady both from Cornell and flight line not all recommending certain chapters from the 57 year book of agriculture which is basically oriented towards farmers and people who would not go on to university but I was hoping that there was something a little bit. Had it been crystallized a little bit more directly toward my concerned homeowners another series might look at it a little off the topic in terms of just the soil science but the Ecological Society of America has been putting out a series of reports to the coal issues in ecology in there about 10 to 12 page things very solid science behind them they're endorsed by panels of the Ecological Society but they're done written for the lay public and Peter of the two Zick wrote one of those in 1907 on this global nitrogen issue.

I was the lead author of one in 2000 on the coastal nitrogen issue and I think both of those would be good general sourcebooks on the nitrogen problem. Oh terrific thank you. Thanks for the call well which is about the part we're going to have to finish I guess the question I'm left with is is this something that you think we are going to be hearing more about. Or is it that the problem's not going away. And I'm sure we'll be hearing a great deal more about it I the science is becoming increasingly clear cut and I think the scientific communities increasingly becoming dedicated to moving this on as a topic that needs solving I view where we are with this nitrogen issue is about where we were with reaching the public with climate change 20 years ago. I'm sure we'll be hearing more about it. Well I thank you very much for being with us to talk about it. Appreciate the update and do something our guest Robert Hall with he is David R. Atkinson professor of ecology and environmental biology at Cornell University here visiting campus of the University of Iowa.