Episode 567 Water Sustainability

Nandita Basu is a professor at U. of Waterloo who studies the processes on farms and wetlands that affect the pollution of water in lakes. She is a modeller, so she collects data about fertilizer use and animal manure around the world, combining the data to see overall patterns is the whole data set, since particular areas differ. For the video, audio podcast, transcript, and public comments: https://tosavetheworld.ca/episode-567-water-sustainability.


Nandita Basu



wetlands, phosphorus, thinking, great lakes, water, soil, data, lake, algal blooms, blooms, restore, algae, methane, papers, talking, pollutants, farm, manure, called, apply


Nandita Basu, Metta Spencer

SUMMARY Episode 567 – Water Sustainability

In the conversation Metta Spencer hosts Nandita Basu, a data science researcher and modeler at the University of Waterloo. Basu is a joint professor in the Civil and Environmental Engineering department as well as the Earth and Environmental Sciences programs. Her focus is on water sustainability and ecohydrology.  She works with available datasets collected by various entities, including government agencies and other researchers. She utilizes AI and machine learning techniques to analyze and model the data to predict the outcome in several scenarios.

In some situations, it is challenging to collect data from various regions due to the language barriers. Much of her research is garnered from reviewing research papers and digitizing information from graphs and charts. She provides an example of a student from China who collaborated with her on a project assisting with Chinese-language papers. The student’s proficiency in the language provided a vast amount of data from that region.  The implications of the political climate can influence research accessibility in some locations.

In this meeting Basu discussed water quality, agricultural practices, algal blooms and their effects on the Great Lakes as well as other bodies of water. She touched on some of the challenges posed by nutrient pollution, especially excess phosphorous and nitrogen from agricultural runoff, and how this causes eutrophication, algal blooms, and other water quality issues.

Basu discussed the impact of livestock manure and chemical fertilizers as sources of nutrient pollution. She also explains that improper manure management can contribute to nutrient runoff into bodies of water complicating the problem.  This is particularly true in concentrated animal feeding operations (CAFOs) or feedlots where a high number of livestock produce a large amount of manure. Yet, there are potential solutions such as using biodigesters to convert manure into energy as well as effective management of nutrient application to reduce pollution. She explained the importance of finding the right balance between using manure as fertilizer for crops and preventing environmental degradation.

There can be benefits to using manure on fields as it recycles nutrients back into the soil improving soil quality and fertility.  This is where controlling the timing, location, and application rate are crucial to protect our water sources and groundwater. Cover cropping, buffer strips, and precision agriculture can also assist in mitigating negative effects.

Algal blooms were also discussed, and Basu explained they are primarily fueled by phosphorous and nitrogen runoff into water bodies. Despite this, not all algal blooms are harmful, but some do produce cyanotoxins which can pose a risk to human health as well as aquatic ecosystems. This is most prevalent in shallow bodies of water like Lake Erie and is due to limited buffering capacity.

It is also necessary to shut down drinking water treatment plants when toxins are present, fish populations are harmed due to oxygen depletion, and if there are risks to pets and wildlife. Algal blooms are increasing in frequency, and they impact various lakes and ponds. This affects cottage owners and those trying to enjoy recreational activities at these water locations. Hydrogen sulfide occurs in low-oxygen condition.  Basu mentions a case in California where the emission of hydrogen sulfide gas led to the tragic deaths of individuals, underscoring the importance of effective management.

Basu touches on the challenge of legacy phosphorus in lake sediments which can contribute to ongoing nutrient loading and algal growth. She explains it is necessary to use a multifaceted approach to address water quality issues such as reducing runoff from agriculture and urban areas, improving manure management, and possibly implementing technologies like biodigesters to mitigate pollution. This is where research, monitoring, and proactive management are important for water quality.

The conversation delved into the role of wetlands in improving water quality downstream. The wetland acts as a natural filter, trapping nutrients and pollutants before reaching water bodies. Basu discussed a study that investigated wetland restoration on water quality in the Mississippi River Basin.

Basu’s most recent paper focused on wetland restoration and its impact on water quality. The study aimed to determine how much wetland restoration is needed to improve water quality in the Gulf of Mexico and Mississippi River Basin. It highlighted the significance of wetland restoration in reducing pollutant loads and improving water quality throughout the basin.

Basu ends the discussion talking about her future research goals which include further attention and exploration to water quality issues. She mentions a new project called “solution scapes” which will create maps to identify optimal locations for interventions such as wetland restoration and biodigesters. The conversation ends with Metta Spencer asking Basu to stay connected so they can further the conversation in the future. 


The following transcript has been machine-generated using “otter.ai.” Prior to using information from the transcript, please watch the video to catch any obvious errors.

Metta Spencer  00:00

Hi, I’m Metta Spencer, today we’re going to go not very far away, we’re going to go to Waterloo, Ontario. It’s just an hour or so away from where I am now. And we’re going to meet a professor who is an expert on water sustainability, Nandita Basu. And she works into departments I gather in civil engineering and in some sustainability project program too. So I’m gonna get real smart today, I just need all kinds of education about water sustainability, and especially some of the challenges of the Great Lakes, which I believe Nandita has made a breakthrough of some kind on I read, I came across her name in a newspaper or something, and I thought, this is somebody I ought to meet. Because I want to know more about what’s wrong with eutrophication in the Great Lakes, if that’s what she does. So good morning, Nandita. How are you? Good morning, Metta?

Nandita Basu  01:04

Good morning Metta, I’m good. How are you?

Metta Spencer  01:05

Great. Okay, let’s get acquainted, we have met now, a good three or four minutes ago. And I’m a retired professor too. So kind of know a little bit about the academic world, but not very much about water sustainability. And what tell me what it was that I saw, as saying that you had, I don’t know, receive some kind of recognition for some research breakthrough. So tell me about your your glory, and and then we’ll run out from there. What did you do that was noteworthy that everybody’s celebrating. .

Nandita Basu  01:48

So I don’t know exactly Metta? The what the, the piece that you read, there’s been a couple of things that our group has been engaged in or working on in the Great Lakes, I lead a project called Lake futures. And the idea of this is to think about the Great Lakes and the future of the Great Lakes. So how do we maintain the water quality or improve the water quality in the Great Lakes while keeping on with economic activities, crop production, and there’s also a lot of urbanization that happens there. What are the solutions to these, we do work on wetlands, thinking about wetlands and what they do in terms of improving water quality. So multiple, multiple different areas of work, but broadly thinking about our water resources, and what threatens our water resources.

Metta Spencer  02:39

You know, before you get down to telling me what I asked you about, I’m already going to sidetrack you with another question that’s not quite relevant. I want you to tell me about wetlands because I am not clear. My original impression. And it’s not totally based on nothing, is that wetlands are a source of methane, that things like rice paddies, and swamps. And things are places where we have the possibility not only of methane, but other things like swamp gas, hydrogen sulfide, and that, that overall, the wetland is a source of bad things. But I’m everywhere I go, now, I’m reading articles saying we got to save her wetlands, because that’s our future. Please explain to me what the truth of the matter is.

Nandita Basu  03:44

So that’s a really good question Metta,, because I think that’s one of the challenges with wetlands, right. So there’s different things about them that are all true in different ways. Right? And and sometimes we get lost in kind of the many different ways. So yes, MATLAB and wetlands can and do emit some methane. But my wetlands also sequester carbon, because all the vegetation in the wetland, they capture the carbon dioxide from the atmosphere and store the carbon in there, right. So there is there is a good and a bad and I think scientists are still grappling with is the good better than the more than the bad or the bad more than the good. It’s not it’s not an easy story, right? And that’s one of the challenges is yes, they capture carbon and they build up carbon over the years. And specifically, if you’re looking at older wetlands that have been there they are net sinks of carbon. So there’s carbon that comes in and gets stored. And there is also methane, which is also carbon that gets emitted like which is more, is it more getting more in or getting more out? Depends is a little bit of the answer to that and people are trying to figure it out. There’s studies that show that Despite the methane emission if you for example reworked peatlands, you get a net carbon sink. Also, on the whole, it’s better. But this is exactly one of the questions that we are tackling in our new project called solution escapes. So thinking about wetlands in, in these agricultural landscapes, and, and and thinking about all the goods and the bads, and kind of tallying them up to say, where can we get more of the goods because all wetlands are not the same, a wetland in one location might be different. So trying to really understand which wetlands might have a better in that good ball mode. And then good for what, right. So there’s different different values that it provides. So that’s kind of some of those questions that we are answering what part of it but wetlands also take up a lot of the nutrients and store them again, because they store these things. They prevent them from going to your lake. So when the nutrients do not go to your lake, your algal blooms are less.

Metta Spencer  06:00

Okay, well, that relieves me because I thought I was dumb, but I’m not totally dumb then. Good. That’s because it’s a real question. Amazing.

Nandita Basu  06:13

It’s not an answer, it is something that.

Metta Spencer  06:17

Okay, thank you for that. But what what, by the way? Would you say something? They’re not all equal? Can you give me a tip about what kinds of factors determine whether it’s good or bad? For example, I believe I, some months ago, a year ago, I saw something saying that the you know, there’s a lot of wetland on the south west of Hudson Bay, large wetland. And and I believe I read that that is a major source of methane that they’re getting a lot of methane from that area. But then I couldn’t find the reference. And I didn’t get any explanation for why it’s true. What, what’s the truth of the matter?

Nandita Basu  07:07

So the Hudson Bay one, I don’t know. But I will say generally there is whenever, whenever wetlands, the methane emission also always should be looked down together with the carbon sequestration, because those are the two pieces of the puzzle. So So in that example of that, I would say what is the net effect? Right, so if they are emitting methane, but they’re also sequestering carbon? What’s the net effect? In a more kind of things that we have done? We do a lot of work on water quality. And and one of the we actually wrote this opinion piece of a couple of years ago, there was this wetland complex in in Ontario, that was going to be paved over. And one of the arguments about paving over this wetland complex was that they did some environmental impact assessment on this wetland complex. And they found that well, there was a lot of contaminated sediment that it was in that because you know, there’s there’s things that have happened, our area, our lands, our region is very developed, so there’s contamination in there. And their argument was that it’s not the best wetland, you’re wetland in the Algonquin Park. So in those natural wetlands are better, right? And so it’s okay to destroy maybe this one for for something and then we’ll build something over there. We construct an opinion piece we wrote with another colleague of mine, Rebecca Rooney, who’s a biologist, is primarily the main idea being that a wetland that is near your agricultural area or your urban area is capturing those pollutants that you need to be captured before the water goes to your shore. A wetland and Algonquin Park has other benefits, but it won’t capture those pollutants because they’re not there. It’s or it’s around there. Right? So wetlands, different areas provide different function. And wetlands in our very developed Southern Ontario are kind of like the water filter in your home. They clean your water before it goes to the lake. And all these beach fouling are these regular things. We have beach closures, so they lessen that.

Metta Spencer  09:15

And if they paved over this wetland, would it? I presume it would keep it from ever functioning in that way again, as a filter, right? Exactly. Yeah. Now I have heard the most remarks that I’ve heard saying we have to save our wetlands have to deal with the notion of reversing the fact that so much wetland has been drained and that that is always bad is that always the case or not?

Nandita Basu  09:49

Always the case. We have drained so much of our wetlands and the wetlands are kind of this unique ecosystems. They provide so many functions like you. They provide protect against flooding, they improve the quality of our water. They sequester carbon, biodiversity, they are extreme biodiversity hotspots. So there’s just so much value to wetlands. But also wetlands soil is very fertile, right? Because there’s a lot of carbon in that soil. And so there, this is the reason we have drained wetlands. Because when you drain that wetlands, that’s prime agricultural land if you can drain it well, right. And so we put these drains that are called tile drains under these wetlands, because water puddles there, and we want to take the water away, because we want to grow crops, so they have been drained over in I mean, in our regions, I would say we trained at least 70 to 80% of our wetlands.

Metta Spencer  10:42

Okay, and that makes them not a sink anymore. Right? Also, my, I have a lot of contacts with Russia. And I remember about three or four years ago, they had huge fires that were underground, the wet the peat from, you know, hundreds of miles apparently caught fire, and apparently, it’s almost impossible to put out. So even there was smoke. I don’t know how the smoke got out. But there you go. My friends were having to move out of their apartments and homes because of the smoke. Is is that? It is is I mean, I presume that means that the main advice we can say is don’t ever do that don’t drain it, and can you restore land that has had that done to it? During …

Nandita Basu  11:36

So the short answer to that is, is is No, when you restore a wetland for you to get back to the natural wetland, it will take many many years. But that doesn’t mean you should not restore wetlands, which you should restore wetlands because they do even when they are not fully functional as they were in the original state. Still, they are very useful. So we are studying a set of these eight wetlands in in southern Ontario with ducks Canada. And and one of the things that we are seeing is and these are all small wetlands in Formula farms, right? So spawn ponds more, and they are so effective at catching nitrogen and phosphorus in them. So and these are restored wetland in these form fields.

Metta Spencer  12:25

Okay, so it can be done, but it takes time. Okay. Thank you. I’ve diverted you now from the telling me about your your wonderful accomplishments. So thank you for the side trip. But nevertheless, let’s get back to work.

Nandita Basu  12:40

No but it’s a big, so wetlands are one of my the ideas of wetland conservation and protection and restoration is one of the key pillars of our work. And and one of the things we are doing is asking this question specifically, right, which wetlands to restore, and what kinds of benefits that we will get by restoring them. And also being very honest about it, what kind of negative things might happen to really understand what are the pros and the cons and and try to understand that like, Florida wetland here versus a wetland in the Algonquin versus so different kinds of wetlands can provide different kinds of functions or values. And it’s important for us to understand that.

Metta Spencer  13:25

Can you do anything experimentally? In other words, could you take a piece of land and wet it, and just measure the methane emissions and see whether it was, you know, at and also, how much carbon sequestering and just get a ratio one to the other?

Nandita Basu  13:44

Yes, and there’s people there’s people in in Canada and all over the world that have done and are still continuing to do that there’s a huge amount of wetland restoration, and that’s ongoing. The study we are doing in Ontario is that where there’s a bunch of wetlands that have been restored, and my colleague, Tony Alden Santo is studying methane emissions from those wetlands versus national wetlands. What our group does is a lot of kind of data assimilation, because there’s so much experimental data that’s available. We do what we call meta analysis, which is gather everybody’s data from all over the world from many years, and then kind of put all that data in a big pot together and say, Can we see some of the things coming out of it? Because when you study one wetland in one place, you could see well, your wetland is different from why wetland because there’s just so much heterogeneity. So as you get more and more data in this part together, you can get more and more confident.

Metta Spencer  14:46

Okay, that sounds good. But that depends on your being able to measure everything that you would need to measure. I’m not sure whether you can’t Can you tell me how much you can expect to do by way of measuring methane emissions and measuring carbon sequestration.

Nandita Basu  15:07

So there’s many methodologies people have been working on not my area of expertise. But generally, there’s there’s methane when met, methane is emitted, it can be kind of diffusing out through the water, it can go through the plants. So there’s many ways of measuring it. And people have been perfecting those ways. They put these funnels in the water and kind of get the gases trapped the gases in the funnel. So there’s many methods and many instruments to do that. So yes, you can, of course, these methods keep getting better and better, and no end to improvement. But we have ways of estimating how much how much methane is emitted. And also the way people do carbon sequestration is they would take the soil columns from the wetland, and then he would understand what data the soil columns figuring out what part of the soil came, what’s the age of that soil and figure out carbon sequestration?

Metta Spencer  16:03

And, well, I’m glad there’s progress. It sounds hopeful. Thank you. Now get back to telling me about your glories. What have you done that’s, that I should remember from having read but don’t.

Nandita Basu  16:16

Um, so as I said, I saw that this is, broadly our goal is to think about water quality in Lake Erie, a part of our work focuses on thinking about this question of legacy nutrients. So the idea is that you’ve been applying nitrogen and phosphorus to our soil from the 1970s 1960s. Right, it’s been a long time, and some of the phosphorus gets stored in the soil. So that even if you reduce applying phosphorus that can bleed out. So we’re trying to figure out how much where it’s stored in the landscape? And how can you use that effectively. So we map out we look at agricultural data, kind of map out what the phosphorus inputs and outputs are, where the hotspots are, and and how much potential legacy phosphorus can be in our sediment in our soils. The plus of this is if there’s legacy in our soils, then you can apply less fertilizer and get the same crap out of it, but you can protect your water. So that’s one kind of area of our work that we are looking at.

Metta Spencer  17:30

Okay, that sounds a little familiar to me, because I’ve, I’ve already had conversations with people about the dangers of of chemical fertilizers, or synthetic fertilizers. And I believe most of the problem does come from fertilizer. That’s it.

Nandita Basu  17:49

Yes, fertilizer Well, so what Realizer as in chemical fertilizer, but also livestock manure is a big part of that equation, too. So it’s both chemical fertilizer and livestock manure that is responsible for the extra nitrogen and phosphorus we see in our water.

Metta Spencer  18:08

Yeah. Now, you’ve mentioned something that kind of threw me off balance, because I’ve been thinking of I have only heard of manure, animal manure, as something highly desirable as a way of adding fertility to the soil. But now you’ve thrown it in together with this bad stuff. That’s a pollutant. When is it a good thing? And where is it? pollutant?

Nandita Basu  18:41

So it’s, again, the same idea, right? That something can be both good and bad, depending upon where and when. So you’re absolutely right. I mean, your adds nutrients to the soil adds carbon to the soil. And traditionally, when people had small farms and small livestock operations, that’s what they would use on their crops, they would use the manure on their crops. But what happens with livestock manure a lot of times is that they are produced a lot in some locations. And it’s, when you apply it, view need to apply to over a much larger area. So you’re not applying too much too much as nothing is good. It’s the same thing about our food, like we need food, but if you eat too much, we get sick. Similarly, manure is a good thing. It’s needed for the crops, it’s the nutrients, but a lot of times because many or is also not easy to transport to further places, if you’re producing it at one location, you might apply it near that area, and you might apply too much. So if you’re driving

Metta Spencer  19:45

So a feed lot for example, it would be a place where you get too much in one place. Is that it?

Nandita Basu  19:53

Exactly, exactly. Now, a lot of times you can smell it when it’s applied and a lot of times it’s applied sometimes it’s also applied on top have snow, which is a really bad thing to do, because then even then the event crops are not there to take it out. So it just runs off into your water.

Metta Spencer  20:11

Okay, now, okay, now, again, you’re triggering an association of mine, which I hadn’t expected to explore with you, but let’s do it. And that is, I’m going to be publishing on the next issue a magazine, a transcript of a conversation I had two years ago with a professor at the University of California Davis, who specializes in the emissions of enteric emissions from cattle. And he is very much in favor of, of the meat industry, of ranching and so on, and defends against, well, I can, loosely saying, against the vegan world. And so I thought it was extremely interesting and was very controversial, I expect, all my friends are going to hate me because my friends are becoming vegans. But at any rate, the argument there is, and he does, he was not particularly the one promoting this argument. In fact, he doesn’t, he says he’s not an advocate of this holistic management approach of Allan Savory and his followers. But I’m, you know, I tend to be very impressed by Allan Savory, his work, and the people who are using his ideas. And the idea there is that you want just the right amount of manure, and urine and other things to be applied to the soil, and sort of the soil should be roughed up a little bit. So if you keep herds of animals in big clusters, and move them from one paddock to another, at just the right time, they will have stirred up the soil, eaten the grass, and left their poop and stuff in just the right amount so that they enrich the soil and make it fertile again. So they I’ve seen dozens or hundreds of photos of land that has been restored from desertification, by this method of herding animals and stead of allowing them to scatter freely over large pasture, you keep them bunched together, and move them at specific times when the they’ve done just the right amount of of work on the soil, and that it does involve adding the nutrients from the manure and kind of stirring it into the, into the top of the soil. Tell me what your impression is of this theory? Because I’m going to call it a theory and well, it is an approach, let’s say, and does that have any bearing on, on what we’ve just been talking about in terms of the the, the predominance of the polluting quality of manure as opposed to being a benevolent thing for the soil.

Nandita Basu  23:25

So I’m not an expert on dairy systems, but I would broadly say my understanding based on peer review literature, is that at the rate of meat consumption that we have, the density and and wood that we need and the consumption of water and other nutrients that cattle production needs. There is inherent unsustainability with it and and some of these viewpoints about it could be done stainability I’ve not seen peer reviewed numbers that really speak to that well. So that’s kind of broadly there’s multiple ways people talk about doing it. There’s there’s there’s some that are better than the others. But and, and part of it is kind of like this is more personal. It’s to me it’s not about these extreme, extreme viewpoints about let’s all go vegan versus everything is okay with, it’s more about recognizing meat consumption and thinking about it in a holistic way. Thinking about maybe reducing it but not going completely. So there’s just these these multiple layers of of that that conversation, but livestock production takes up a huge amount of just to feed the livestock right? If you forget everything else, just to feed the livestock. There’s huge amounts of 10 times more or 100 times more pasture crops that you need and to grow that you would need nutrients to be added to the soil. So there’s there’s many, many There’s a two line argument.

Metta Spencer  25:03

That’s very informative. Yeah, because I want to hear all sides. And it certainly is controversial. Okay, again, I’ve I’ve steered you away from your, your preferred area, you want to talk about the Great Lakes. And..

Nandita Basu  25:18

Yes, one of the things is this livestock piece. So one of the things that we realized with our work is, we always definitely blame chemical fertilizers. And I think chemical fertilizers is definitely a big piece of the puzzle. But livestock manure is also an important part of that puzzle. And, and, and proper manure management. So some of the models we developed basically says that if we focused our attention on proper manure management, we could address some of these issues much better. And so this is kind of led to another project that we have, which is asking the question, if you added biodigesters, to the landscape, so when you take them in urine converted into energy and figure out ways for effective taking the digestate and applying it to soils, in amounts that you need, might be a economically viable options. So we have this project that’s evaluating how feasible it is at the landscape scale, what are the costs and benefits and things like that?

Metta Spencer  26:23

Okay, when you say biodigesters, to the new word for me, what’s that about?

Nandita Basu  26:28

So these are, these are a plant these are where basically, you take money, or you might take food waste, and you have bacteria digest this material, break up this material, or like in a wastewater treatment plant, right, so they’re breaking it up, and you actually can generate methane out of it, you can capture that map pain and convert it into energy. So there’s local options, while local, like larger scale dairy farms sometimes have these anaerobic digesters on their on their farm, where you can actually use that and get energy out of it. And so you can, you can have electricity for your region with that. And then you also produce digestate, which is kind of the solid material that comes out of your Digester. And then that digested also has nutrients in it. So then you have to figure out where you apply the nutrients, but sometimes those might be easier to transport over larger distances, so you can apply it to the landscape.

Metta Spencer  27:31

[Inaudible] that I talked to two years ago was talking about, he lives in California. So he says it’s a big business now, they have lagoons he calls them lagoons where they put the animal waste and then nowadays they put a plastic or some kind of tarps over the top of the lagoon to keep the methane from escaping and then they captured and can use it and I think then it I don’t know whether he didn’t say the about bio digesters, but I think he was assuming that it does on its own produce methane and then the residue can be used as fertilizer.

Nandita Basu  28:20

So that is one of the kind of lower end but there’s much more also technologies available that to fasten up the process so it becomes economically efficient at a larger scale, and there’s…

Metta Spencer  28:33

What would they put into the the waste material to..

Nandita Basu  28:40

Bacterial and various chemicals again, our the functioning of the digester is not something that I have expertise in but it’s it’s it’s similar to your wastewater treatment plant right in a in a wastewater treatment plan when you get wastewater and solids that you put them through these digesters biological digester systems with that that break down so so in a natural system, there is bacteria that would break it out but you want to speed up that process so you get more energy out of it for the tiny are investing in it. So and there’s multiple technologies and technologies are getting better and better. There is also Canadian Biogas Association. So there’s companies that that to build these digesters and, and there is also this is not just about livestock waste, it’s also about municipal waste. So there’s…

Metta Spencer  29:29

It’s like a tank and they put chemicals in the tank along with the waist. Exactly. Okay. Now, are there people actually doing this now or is this kind of a dream? Sure thing.

Nandita Basu  29:43

It does exist so there’s there’s it exists a farm scale yesterday, a colleague of mine was telling you about one farm in Elmira that has it it’s done in municipalities. I have a colleague in at a who is doing a lot of these anaerobic bio digesters for municipal waste, the technology exists, it’s good. There’s a group of people in Waterloo and elsewhere that are doing research on how to make this technology more and more efficient. The technology exists, but it’s still not done on a large enough scale, because there is this cost benefit aspect to it. If you are a large enough farm, you can afford it. If you’re a smaller operation, you can’t really afford it. The project that we are doing is kind of asking this question, if there were trackers that tracked them to a centralized location, how many we wouldn’t be cost effective? Like how many would you need across Ontario? Where would they located? And what are the costs and benefits of those kinds of processes?

Metta Spencer  30:47

Now, this cannot be really completely new idea. Because I was in China as a visitor in 1980. And I think it was, you know, they’d probably showed us around to their, their showcase farms and not typical farms. So I doubt that this was widespread, but we visited a family in their firm that had a system whereby they collected their human and animal waste and got it and collected the effluent I mean, not the effluent that I suppose the gas, it must have been methane, but I don’t think they told me what the chemical, you know what the gas was. But they use the gas as a fuel or as a lighting system. I think they had like kerosene lamps or something equivalent that they use for their for their lighting, and use the products of their farm that way. So that was 1980. I’m sure that what you’re talking about is vastly more sophisticated. But this this was certainly a primitive precursor, I would assume.

Nandita Basu  32:01

Yeah, yeah. And the technology is not new, the technology has been there. And it’s improving what what our work is focusing on is asking, it’s still not used in a widespread way. And that’s because about the cost and benefit of the process. It’s, it’s not economically so if you do the math, you will see you have to be have this many cows for it to be economically feasible for you to undertake the capital cost of this technology. Right. So only larger operations habit, what our project is looking at is, if you wanted smaller operations, to have smaller farms to also use them in your that way, you need somewhat of a centralized system, where many forms would pool into this resource. And then you would have to think about like, if you want to track your money or to a centralized facility, what are the costs of that? Who is doing it? So that’s kind of what we’re trying to do and where do you want them? We want these facilities to be there. So that’s kind of figuring out how we can be made cost effective at a large scale, the technology does exist.

Metta Spencer  33:08

Okay, well, let’s talk about the Great Lakes. And what I suppose I want to ask you about eutrophication, but also other algae, I believe your work involves something about how to manage algae in Great Lakes, tell me about it.

Nandita Basu  33:28

So, so, in essence, the idea is that we put fertilizers on on our crops and fertilizers have nitrogen and phosphorus and phosphorus is has been shown that it is what is causing these excess algal blooms. And and and sometimes these algal blooms can also be toxic. So they emit these toxins. And so what our work focuses on is, is understanding how to reduce that phosphorus application while having the same kinds of crops that you want. What aspects of the landscape are important when you’re thinking about phosphorus, how to manage. So this is why like one of the solutions, and this is put wetlands and then we say, well, where do you want to put this wetlands? Where if you want to maximize your Phosphorus Removal, right, which which locations? If you another solution is well, you do not put so much extra manure on the land. Well, what do you do with it? You can just tell the farmer don’t put it they have to do something with it. So this is where the biodigesters can we make a cost effective way of thinking about this digesters across the landscape, that will reduce the extra phosphorus that you’re putting in that will mean that there’s extra pastures that goes to your lake and causes these algal blooms.

Metta Spencer  34:48

Okay, so you’re not out there in the in the water so much as you’re on land, trying to take care of the things that are gonna get into the water before it gets there. Okay. Ay, ay. Yeah. Okay. That’s that is.

Nandita Basu  35:06

And so in the broader project of like future is not my work. There’s others that work on the lake, right? So there’s there’s there’s so our, our our subgroup works on the land that drains into the lake. And there’s also a SAR group that works on more the lake processes and also thinking about lake sediments. So there’s legacy phosphorus in lake sediment and what that means in terms of water quality.

Metta Spencer  35:30

Oh, all right. Well, tell me a little bit about that. Because I hadn’t thought about that. What? So if there’s, there’s legacy phosphorus or nitrogen in the lake, it’s at the bottom? And does it do any harm? Or is it…

Nandita Basu  35:48

So it can, it can potentially release into your water column and provide phosphorus. And that’s the part that we’re trying to figure out how much comes from the sediments released to the water column, because when you have sediments that is released from the sediment to the water column, that’s called internal loading, that phosphorus can also be used by algae to grow. Right, so we’re trying to figure out how much of it comes from today’s land, how much of it comes from pastures that you applied 10 years ago, versus how much of it is in the sediments sitting in there. So really trying to understand the different pieces to see where if you go and make a change, you will see improvement.

Metta Spencer  36:31

Now I believe that not all the great lakes are equal in the extent of their pollution or their eutrophication. And I you you mentioned Lake Erie is Lake Erie the most advanced in its [inaudible].

Nandita Basu  36:50

Yes,  it’s shallow, one of the reasons it is so so much of a problem. So when a lake is shallow, then it heats up in a different way. So when you add pollutants to a shallow lake, there’s not as much buffer to absorb the pollution. So that’s why you get more algal blooms in the lake versus the same pollution in a lake like Lake Michigan, which is deeper might not give rise to as severe problems as you see in Lake Erie.

Metta Spencer  37:23

So what is the actual you know, problem with Lake Erie? What how who’s being adversely affected by the the state of the water? And is anything being done to try to clean it not not your end event where you’re going to prevent it from happening, prevent it’s happening, but clean it up? Now that it has happened? What is being done that way?

Nandita Basu  37:54

Um, so multiple different things. The first saying who’s post question about who’s being adversely affected — multiple. What happens in the process of eutrophication is every year you get the phosphorus from the land that comes to the lake in spring runoff when you have your snowmelt runoff, and that fuels this blooms of algae that grow. Sometimes you get toxic blooms, and there was this one case where Toledo the drinking water treatment plant in Toledo had to be shut down a few years ago when there was this huge toxic bloom that happened. Also when you have a toxic bloom of course you take your take your dog to the beach, and there’s there’s incidences in different regions where where they’ve gotten sick. So

Metta Spencer  38:50

They’ve been poisoned the dogs.

Nandita Basu  38:53


Metta Spencer  38:54

So are they more more susceptible than people?

Nandita Basu  38:57

Yes, and also they are in the water more than people like if you a lot of times there’s warnings but then dogs will still go in. So so there’s there’s there’s when you have toxic blooms, that’s a big, big challenge. And the one thing I would also like to reiterate we think a lot about the Great Lakes what we also really are encountering which we should talk more about is all the other smaller lakes that are in Ontario. It’s not just the Great Lakes so I my project manager Laura, she was talking about some blooms being spotted in the lake on which her cottages and and she’s disappointed that she can go swimming because some blooms have been spotted right? Because whenever there are blooms that are spotted and you and this these blooms were blue green algae which had the potential to be toxic blooms you don’t want to go swimming in that lake.

Metta Spencer  39:51

Can you see it? If you’re if you’re walking along the edge of the lake, can you tell there’s a spot of it?

Nandita Basu  39:59

So you can say If that there are algal blooms in the lake, there are some kinds of algae that those are the Bluefin algae you might be able to see and but whether they are toxin producing or not, that’s not as easy to detect that way. There’s multiple tests to figure out. But blue green algae, you can, you can see. And then also there are these things where you can find reports on if there’s algae watch, and a lot of other organizations that work on detecting and providing information to public so don’t go there. But that’s one of the…

Metta Spencer  40:35

I’ve seen lakes that have green scum on it. Slime. Now, obviously, I’m not gonna go into that lake. But in fact, I think I’m thinking I used to teach at the University of Toronto Mississauga. And there’s a pond there. I haven’t been out there in ages, but they did have the slime on it. But the ducks and the geese nevertheless, were there was is it okay for for ducks and geese? Or do they ever get poisoned? Or, by it.

Nandita Basu  41:08

So all of the green scum is not necessarily toxic algae, right? So there’s a ton of just algal blooms that you would see. And they those algal blooms are, are, are, have their own problems. So even if you don’t think about toxic blooms, regular algal blooms, what happens is that there’s a lot of plant matter, right, so these ugly algae then sink when they die to the bottom of the water, bacteria degraded consume oxygen and turn the water to be low in oxygen content. And when that happens, you have fish oils and things like that. So that’s kind of one of the impacts of algae, whether they are toxin producing or not.

Metta Spencer  41:48

Okay, so it kills the fish. And I guess it also kills the ducks and everything else, right.

Nandita Basu  41:56

But they would probably, I mean things that can move away, a lot of times will move away. I think a lot of times when you have those three times, they won’t stay in those regions. But as you go around, it’s everywhere, like every pond that you go in somewhere has an algal bloom around these regions, right. It’s tough to find ones that don’t.

Metta Spencer  42:17

Really okay. What I was wondering is if it if it happens one year, can you be sure that it’s going to keep going when next year is on? Or do you sometimes have an outbreak and then clean for years?

Nandita Basu  42:34

So it’s not necessary? So depends on which lakes we’ll be talking about. So a lot of times when you’re thinking about these lakes that are more in forested areas, or not so much agriculture, lakes that you have cottages by, and those lakes blooms have been increasing, which means that you’re not necessarily seeing it every year, but the frequency of you seeing it is increasing. So and it varies from year to year. Because it depends on when your rains happened, when the temperatures increase the specific kind of climate thing. So it varies from year to year.

Metta Spencer  43:15

And the wintertime it’s going to die that this stuff has gone right?

Nandita Basu  43:21

Yes, yes. But then it comes.

Metta Spencer  43:24

But it’ll come back. Okay. Mm hmm. Okay, well, so this is affecting cottagers? Is that right? That they are concerned? They don’t want to go in the water that can they? How do you tell? I’ve heard I can’t remember the name of it. But there’s one particular kind of an algae that I think is supposed to be really, really bad really dangerous, does it start with a “c?” [Cyanobacteria]. Okay, the cyano sort of implies that it contains cyanide, is that true?

Nandita Basu  44:03

So I don’t know so much about the toxin content honestly. So to be able to do but those are Cyanotoxins are what these what these algal blooms are and those are the toxic blooms and they are coming up they come up in sometimes in our reservoirs and then there are there are warnings that our drinking water treatment plants have. So when they detect that then they would have to figure out ways to treat them or get other sources of water till that goes away. So it is it is a very real continuous problem that is increasing in our waters.

Metta Spencer  44:37

Okay, but now some of these cottagers I assume use buckets of water from the lake and might not know what what’s in it.

Nandita Basu  44:49

So I mean, I think a lot of the cottagers that I talked to have talked to the at least for their drinking water, always do bottled water and I always recommend always do bottled water because even when you’re not seeing anything visually, there’s a ton of stuff in these waters that are not treated, you do not want to drink them. So if you’re using them for other purposes, maybe that’s okay as as long as there’s no sign of toxins in it, but definitely not for drinking.

Metta Spencer  45:25

Now, one of the things that I’ve heard also is hydrogen sulfide, I think it’s called swamp gas. When does that occur? And is that I remember reading about a year ago, but a couple and their dog and maybe a child were out walking in, I think it was in California. And they were all found dead. And nobody knew what you know, went wrong. They just all dropped dead, apparently. And apparently, they the best thing, configure is that what there was hydrogen sulfide emitted from something in the vicinity. Tell me about that. If you don’t have any worry about let’s start worrying about hydrogen sulfide.

Nandita Basu  46:11

There are many reasons why that can happen, right? And it’s tough to I mean, there’s there’s natural sources of hydrogen sulfide gas from very reducing conditions. So whenever whenever a condition, if there is sulfur in a system, and it goes in this condition, that’s very reducing condition, low oxygen condition, you might see emissions of hydrogen sulfide gas. The case in California, you mentioned I remember that I don’t know whether they came to any conclusion on what exactly happened in that scenario, but broadly, I would say our, our, our, our, there’s, there’s incidents of these blooms, and these toxins in areas that we normally think are more pristine, and would wouldn’t think twice about going in a river and drinking water in some areas. And I think the fact that we are seeing more incidences of blooms in these areas is something that we should take seriously.

Metta Spencer  47:10

Okay, so you’re you are doing the research, tell me what you’re, how you’re researching it, tell me you know, how you spend your days? What is it you are looking at? And what’s your, you know, methodology.

Nandita Basu  47:27

So I am a data scientist and a modeler by training. So what I do is, I work a lot with available datasets that others have collected, this includes the province that is collecting water quality data, other researchers that have collected data, and we use a lot of artificial intelligence and machine learning kinds of approaches to try to understand the data, right. So to try to make sense of the data because data can be very messy, and to try to develop models to say, Well, if you do this, what will happen?

Metta Spencer  48:05

Right, so if you give me an example of what have some, some output, your most recent paper, tell me about your most recent paper.

Nandita Basu  48:17

Um, so let me give you one example, since we were talking about wetlands, one of our papers that came out in, in nature in the journal Nature a few years ago, and the main idea of that paper was to ask the question, if you lose wetlands, what will happen if you restore wetlands, what will happen? Right? And in this case, we were asking the question in the Gulf of Mexico, Mississippi River basin, and ask the question, if you restore wetlands, if you if you take away all the wetlands that exists in the Mississippi River Basin, what will happen? And what we found was that if you did that your pollutant load would double or no would go four times to the Gulf, which is a large number. Oh, no. And then if you want to restore wetlands, how much wetlands do you need to restore to improve water?

Metta Spencer  49:18

Okay, now that’s interesting because, of course, I’ve visited Louisiana and I never thought about the notion that the miss it you’re saying that the quality of the Mississippi River and the pollutants that’s going to dump in the, in the, in the, in the Gulf of Mexico is affected by the wetlands on the shore?

Nandita Basu  49:43

Not on the shore wetlands everywhere within the basin every farm fields, right, so it’s not just those wetlands on the shore. It’s wetlands…

Metta Spencer  49:50

How does the water from the river get into all this wetland?

Nandita Basu  49:57

So, it’s the other way around, right. So if you think about a river system. There are form fields that drain that have water from, but that rains on the form fields that drains into the Mississippi River. And then the Mississippi river goes into the Gulf. So it’s all connected. There’s 3 million square kilometers, that is all of the waterfront that 3 million square kilometer goes to the Gulf. So when you put a wetland that traps your nitrogen or phosphorus before it enters the Mississippi River, you’re improving the quality of water in the Mississippi River. And that water? Is that water that goes to the Gulf, you get less pollutants in there.

Metta Spencer  50:39

Oh, okay. Well, I would have assumed that most of the river water had flown 1000 miles from, you know, the upper upper states in the US, and it picked up all of the pollutants there. And that may be too late. By the time it gets to the, I guess they call it a delta.

Nandita Basu  51:00

That’s what I’m saying. That is what I’m saying though Metta. So they do pick up all the pollutants there. But that’s where we restore the wetlands, you restore the wetlands, not in one location in Louisiana, we were talking about restoring in the upper areas over the entire base. Kind of making the point, if you want to solve this problem, you won’t have to solve all of it. You just can go solve at where you’re seeing the problem..

Metta Spencer  51:24

Okay, okay, that makes sense to me. Oh, gosh, that would be very ambitious. I mean, for one thing, I can’t imagine the US government buying it. I mean, imagine what it would take, you need to buy up everybody’s farm. And no?

Nandita Basu  51:42

No. And that’s the thing about this paper. It’s not you don’t need to do that. All you and this is true about Lake Erie, all you need to do is every farmer saying I have this plot of land. And a lot of times these are big plots of land that you have for agriculture. And there’s this low lying spot in my land, which doesn’t get the best crops anyway, I will convert that spot to a wetland. And if every person says that they will do that, it’s like little things, and they will add up to really clean your waters. The same idea in the Lake Erie Basin, you’re not talking about taking away people’s farmland and converting them to wetland, you’re just saying every person has one wetland or two wetlands, that is within their farmland while they are growing crops around it, which some people are doing, then they are cleaning their own water. It’s their own private water treatment filter before it goes and so the water will be cleaner.

Metta Spencer  52:37

Okay, so you just are doing a little public relations or persuasion from not? Could you have legislation? Or do they consider it in terms of say every farm has to do this or that because this is an emergency.

Nandita Basu  52:57

Legislation is always challenging, right. But there are also ways to get funds both in US and Canada towards it. And one of the things we showed is if you did do your most ambitious goal of restoring that many wetlands, the amount of money that you would spend is actually not different than the amount of money that is already spent on a lot of these kinds of things. So what our project are finding is that if you took that money and focused it in ways where you do it, where it’s most efficient, you can actually address the problem better.

Metta Spencer  53:31

Right? So it did you say this was published in Nature that’s a prestigious journal didn’t have some political impact. Did anybody get in touch with you and say,…

Nandita Basu  53:42

So I think the path from the path from when you publish to when it starts getting an impact is a long and circuitous path. What did happen with that paper? Is that du Canada, a duck’s Canada came in and do international which in two CEUs came to us and say, Hey, we got some money to restore wetlands, which wetlands do you think is the best to restore? And so we now have a project in the Lake Erie Basin, asking that question, right. So it’s not that and honestly, in the world of wetland restoration, there is money that’s coming in from like a climate perspective on wetland restoration, both in the US and Canada. And what we where we would like to see our work go is the effective use of this money to restore those wetlands that will have the most effect.

Metta Spencer  54:35

Hmm, sounds like one of the elements of it is simply getting the word out. Because I mean, how many, I’m trying to think of how many people are going to watch the show, and how many of them are going to be farmers with wetland? Probably not many question is how we could get this kind of information out to those people because they’re the ones who might need to be informed about it.

Nandita Basu  54:59

Exactly Metta, and one of the farmers that I was talking to who has the set of wetlands. He talks about it so beautifully about the legacy of this land that he’s leaving. He says, I love my farmland and the farming that I do. But I actually really prized this wetland that I’ve built over here, because that’s what I leave to my grandkids that space and has this beautiful kind of sitting area beside it. It was just a gave me goosebumps to just talk to him how proud I was.

Metta Spencer  55:29

That’s wonderful. Okay, now you mentioned Well, the girl that what you do as a meta analysis, you collect data from all over the world as much as you can get, and put it in one big pot? And do the analysis on that huge data set? Where do you get your data? And is it difficult? And I think that is an interesting challenge, where how does that work?

Nandita Basu  55:53

So it is difficult and time consuming. So the way we would do it is we would first collect hundreds of papers. And then we would go in and see what is the information that they have provided in those papers. Sometimes those might be in forms of graphs, and then we will have to digitize them to figure out that information. So it is really bad braking in terms of that. But our group has this philosophy is that there’s a ton of work that is done. And we really want to learn to build on that work and me. And so that’s kind of a big part of what we do. But it is it is a lot of work to do it.

Metta Spencer  56:29

Well do a lot of other countries collect a lot of data? Or is it it’s really almost all say North America and Europe? And then you just here and there get a little piece of information elsewhere.

Nandita Basu  56:45

That is also a really interesting question, Metta. I’ll tell you why. So when we did the wetland work, we did that. And one of the things we found is that most of the wetland data that we got was from North America and Europe. And then I had a student from China reach out to me and and want to work with me. And I said, What about data in China, because you have a lot of funding that focuses on environmental pollution Do you collect data? And so he now has a paper with us that has done a similar work using papers that are written in Chinese language. And turns out there’s a huge amount of data in China, I didn’t read it and see it as a global community. And he’s now published this paper with all of this data points from China.

Metta Spencer  57:27

So he is able to get access to it, would you be able to get access to it for your own purposes?

Nandita Basu  57:34

So the access in this case, a lot of this data is not government data, it is researchers data, so it sits in publication. So the way you get access to it is kind of go through the papers and, and get that data from that. And these papers are open access. But the work in kind of getting all of that is a lot of work. And for me, I would not be able to do that because I would not be able to read those Chinese language papers and be able to get that data which he was able to and now it’s in an English language journal, and it’s accessible and usable for others to see and be able to use.

Metta Spencer  58:11

Have you thought of and I wonder whether it’s possible to use AI, you know, chatbot stuff to translate. I just did a little translation, I wrote a letter to people in all Latin American countries, short letter and I had GPT four translated into Spanish. I have no idea what it wound up telling them probably who knows what it was actually sent. But it did translate it. And nobody has, as a written me in shock saying, what do you mean by this?

Nandita Basu  58:49

So, of course, I mean, chat. GPT can do a lot of translation. But when you’re thinking about doing this for hundreds of papers, trivial but and also, more importantly, I think it’s important when you’re working with these datasets to help people from that country because they know and live and understand that data in a way that no chat GPT or AI could do right. So to me part of it is also the student who’s now in my lab for a year he’s actually leaving and of this is it’s nice to really understand the context and the value and what’s happening. So it’s not just about mining that data is understanding that data and making sense of it in that context. So I think there is value to having kind of building these bridges because I grew up in India, but I grew up having English as a language that I was very comfortable with. But having being able to bring this information that exists in different languages and different cultures together, I think is really…

Metta Spencer  59:48

Did you find much in India?

Nandita Basu  59:50

Um, so not yet. I mean, I none of my I mean, there is data that exists but I don’t have any specific collaborators right now[inaudible] has to be the right person to do the right thing.

Metta Spencer  1:00:04

Because I’d be curious to know where people are doing research. My impression is that there’s a lot that goes on in China, probably less in India. And I think that the my impression is people in Russia, who are trying to do research probably don’t have an easy time of it. Because I think the government is not enthusiastic about saving the world from climate change. And I don’t know how much that affects their research capacity. Do you? Is that your impression that it has deleterious effects on the quality of research they’re able to do?

Nandita Basu  1:00:44

Absolutely. I mean, it’s amazing to see what’s happening in China with the amount of research that goes on there and funding. And so and it depends on on that as to how much is being done or not.

Metta Spencer  1:00:59

But Russia is the question did you get…

Nandita Basu  1:01:01

I do not know enough about about Russia to be able to, to be able to say anything in the space, my knowledge of Russia goes back to some of the older data sets and papers where I’ve seen amazing data come out of Russia. But I wouldn’t be able to say anything about current current datasets.

Metta Spencer  1:01:20

But of course, now there’s it’d be difficult to interact with them because of the war. But the my impression that was already there was a wet blanket over research on on climate change in in Russia. And I don’t know enough to, I’ve not been able to contact a lot of people that I’d like to interview. Let’s put it that way. Yeah. Well, we’re getting close to the end. This has been extremely informative. Very, very interesting. Where are you going with your research? Next? What are some of the issues you’d like to unpack with your next study?

Nandita Basu  1:02:00

So what I’m really excited about is in the next phase of the research, kind of thinking about these solutions in our new project called solution escapes and other grants. So thinking about developing these maps to say like, which wetlands? Where do you want to put the biodigesters? For many, what are the costs and benefits? What are the trade offs? And doing that at a large scale, both in the Lake Erie Basin, but also in the prairies? Scale this, this, these things up and, and really keep working on all these ideas?

Metta Spencer  1:02:33

Well, I hope you’ll keep me informed about what you’re doing. Because it’s so interesting. And it is really, to some extent, connected to some of the other interviews that I do. I’m doing a lot about various proposals for helping solve global warming issues. So this is part of it, you know, you’re really right in the middle of things. So keep me posted, if you will. And let’s have another go at this some time, perhaps with some other colleagues who can think of who will think no doubt about questions that wouldn’t have occurred to me, right. Okay. Thank you so much. So much. I’ve enjoyed every minute and hour and I hope to see you again on this. Okay. Bye.

Nandita Basu  1:03:23

Thank you very much, take care.

Metta Spencer  1:03:23

Bye. Project save the world produces these shows, and this is episode number 567. Watch them or listen to them as audio podcasts on our website tosavetheworld.ca you can share information there also about six global issues. To find a particular talk show it or its title or episode number in the search bar, or the name of one of the guest speakers. Project save the world also produces a quarterly online publication Peace magazine. You can subscribe for $20 Canadian per year. Just go to pressreader.com on your browser. And in the search bar, enter the word peace. You’ll see buttons to click to subscribe.




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