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Ecology and Sustainable Food: Jennifer Blesh

Jennifer Blesh discusses the historical and environmental impact of the agriculture industry.
Welcome back to this teach out on food sustainability. I’m here today with Jennifer Blush, who’s an assistant professor at the School for Environment and Sustainability. She’s also an affiliate of University of Michigan’s Sustainable Foods Systems Initiative. And the principle investigator in the Soil and Agroecosystems Lab here at U of M. In this segment, we’re going to talk about how insights from the field of ecology can help us think about sustainability, especially when it relates towards food systems. Thank you so much for joining us today. » Great, thanks for having me. » Yeah, so let’s start talking about the kind of the size and the scope about this issue.
So what can you tell us about the agriculture sector’s kind of impact on climate change? » Well, according to the IPCC, that’s the Intergovernmental Panel on Climate Change. Agriculture contributes about 10 to 12% of global greenhouse gas emissions. So the agricultural sector is an important contributor to the problem. This started mostly following World War II and the green revolution where we had a big change in farms in the US. So farms became larger and more industrial and highly simplified, growing just one or two crops at a time, often. And so that meant the need for external chemical inputs in order to sustain yield without having all of the functions that, in the past, were provided by plant diversity on farms.
And so that simplification and these chemical inputs have meant greater carbon dioxide emissions. For example, most of those inputs that go into agriculture require a lot of energy to produce and then there’s also the energy used to apply them. Agriculture also contributes substantial quantities of methane mostly through livestock production, also through rice. And there’s also a big contributor to nitrous oxide emissions and those are methane and nitrous oxide emissions are really important and powerful greenhouse gases. So for example, in the United States, 77% of all nitrous oxide emissions come from agricultural soils. And this is largely due to inputs of nitrogen fertilizer. So we really need to look at agriculture to affect climate change. » All right, that’s really interesting.
Can you talk a little bit more about kind of the impacts on agriculture and on these systems that grow our food? » Yeah, that’s an important point. Agriculture causes climate change, but it’s also going to be effected by climate change. Some of the main changes that we’re expecting to see are things like increased heat stress on crops and livestock. Just like us, livestock also feel stress from hot temperatures. Longer summer droughts, increased flooding because more rainfall will fall in these extreme precipitation events. So all of these things are going to mean the potential for reduced crop and livestock yields unless we work to improve the sustainability of agricultural systems.
Great, so let’s talk a little bit more about that and those opportunities for improvement. So what can we learn from your work in ecological sciences that may help us manage or even change how our current practices of food production are actually carried out? » Yeah, I would say the good news is that we actually know a lot about how to manage our agricultural systems more sustainably. As humans, we actually have a lot more experience growing food without chemical inputs, about 10,000 years versus this recent history. And all farms are essentially ecosystems and they’ll part of nature so they have basic ecological principles.
And the issue with industrial agriculture is that we’ve tended to ignore those biological processes on farms and instead, apply inputs for crop production. But if we apply an ecological lens, we can think about well, what are those biological processes? How can we understand them better, know how they work? And then think about intentionally managing them to sustain crop production, but also environmental sustainability and other ecosystem functions. So a key way to do this, putting it most simply, is to increase plant diversity on farms. So we can basically manage plant diversity from field to landscape scales for things like adding nitrogen to soils. So a key example for my work might be legume cover crops. We’ve already brought up nitrogen fertilizer.
So that’s the number one use of energy on farms right now. And legumes are plants that have an association with symbiotic bacteria in the roots. And those bacteria can actually convert nitrogen that’s in the atmosphere into forms that plants and other organisms can use. So cover crops, I don’t know if I defined that, but those are crops that are basically, they’re not harvested, but they’re grown in rotation with other primary crops. So if farmers grow legume cover crops, they can use that as an organic nitrogen source and reduce the need for this energy expensive fertilizer. Another example might be reintegrating crops and livestock. So we also talked a little bit about livestock earlier.
Currently, most lifestyle production is happening in these concentrated feed lots. But if they’re grown together on the same farm, livestock eat things like perennial forages, pasture. These perennial crops that can add diversity into crop rotations and help improve sustainability. So one of the things that’s really important from an ecological perspective is we’re going to have all of these effects of climate change. There are ways that farmers will have to adapt. But we also know that improving soil management is really key to both adaptation and mitigation of climate change. So things like legume cover crops and perennials build soil organic matter.
Can you talk a little bit more about kind of the opportunities in terms of adaptation and then opportunities in terms of mitigation and kind of what are the differences between those? » Sure, so thinking about organic matter specifically, it can build the capacity to store and retain water. It can also cycle nutrients. So microbial processes in soil actually provide nutrients to crops. Which, again, allows for reducing these energy expensive inputs. It can reduce some disease pressure. Farmers may also have to adapt in other ways. There are reasons to believe they might have to think about growing slightly different types of crops eventually, potentially increasing irrigation. But improving soil management and soil health are also really important ways to adapt.
And then from a mitigation perspective, not to harp on this issue too much, but soil organic matter is really important. That’s where the carbon is stored in soil. So it basically practices that build organic matter sequester atmospheric carbon dioxide in the soil. » Great, so I image that the individual farmer, and the degree to which they can or are willing to adhere to some of these practices that you’re talking about is going to to be really dependent on state or federal policies around food. Can you tell us a little bit more about kind of currently what’s in the works there and what’s the status food policy is?
Sure, I mean that’s absolutely right that individual farmer decisions are shaped a lot by the policy and market conditions that we currently have, whether it’s in the US or globally. The main overarching policy that influences all of this in the US is our Farm Bill. And the new Farm Bill was actually just passed in December. It’s called the Agricultural Improvement Act of 2018. But Farm Bill started way back with Roosevelt. And at that time in the 1930s, 25% of the US population lived on farms. And there were big economic and environmental crises like the Dust Bowl that sort of motivated that support.
And then through time, the focus of farm policy really shifted with the green revolution and industrialization of agriculture. So if you think about the 1950s, the Farm Bill focused on producing surplus qualities of commodity crops to secure sort of US interests abroad. Then in the 70s, we had Earl Butz with his get big or get out platform. Really thinking about further intensifying and industrializing large scale farms. And that was also through the form of direct payments the farmers for just a small number of crops, like corn, soybeans, wheat, rice, cotton.
So that sort of legacy has left us with what amounts to tax payer support for just a few crops grown in monocultures that have all of these unintended consequences for the environment. So that’s sort of the background of the Farm Bill and where we are today. But there’s also another side to that and farm policy’s really important for conservation. So I mentioned starting in the 1930’s we were thinking about the Dust Bowl and erosion. Well even in the 80’s we started working in these different conservation practices into the Farm Bill, that are things like land set aside, or what we call working lands programs.
So those programs allow farmers to change practices in their fields to improve sustainability and they get cost sharing for doing that. So those things are all really positive. And my understanding in 2014 and now, is that they’ve been increasing to some extent. But they’re still a drop in the bucket compared to those payments that we have for commodity crops. Which today, are through the form of insurance rather than direct payments? So there’s a lot of public pressure and these are increasingly contentious debates. And people are saying we need to think about how we can shift more of the incentives over to conservation payments rather than payments for large monocultures. » That’s really helpful insight.
Can you give us maybe an example or provide us with a little more context on how farmers are kind of applying some of these ecological practices? Especially with kind of the changing evolution of what the Farm Bill looks like. What does that look like in practice? » Sure I mean, a nice example is one of the Working Lands programs which is called EQIP. And under the 2014 Farm Bill, payments for cover cropping under EQIP tripled. And so farmers can plant a non-harvested crop in their rotation in the off-season and receive a payment to help support that practice. There are now payments that support transitioning to organic production, or even some money for ecological pest management and rotational grazing.
So the language that’s in there is quite innovative and relevant to ecological science. The problem is what actually ends up getting funded in practice might be more of a focus on no till, for example, or even just the status quo. And that’s a result of, we know that there are a lot of corporate interests now in agriculture in the US, and that sector has huge lobbying power. And so there’s all of this pressure to maintain things as they are, along with this group of diverse actors that are thinking about how to improve foreign policy for climate change and just general sustainability. » Super helpful. So let’s jump into kind of the household level local context here.
So in other parts of this teach out, we’re talking about kind of the benefits of a household level garden, for example. So from your perspective, and coming from kind of the agro cosystem side of things and using kind of the ecological lens. What would the value of kind of shifting toward more of a locally grown produce at the household level look like? » Yeah, great question. I would say simply that people should grow gardens wherever possible. [LAUGH] It’s always a great idea, particularly for meeting our needs for fruit and vegetable consumption. So I believe that currently in the US, we actually don’t produce enough fruits and vegetables to meet recommended dietary intakes for fruits and vegetables.
So we have a gap there and gardens could help to meet that need. There are other benefits of gardening that are so important. We know they have mental health benefits. There was a recent article about the importance of getting your hands in the soil. [LAUGH] And there’s potentially microbial mechanisms going on there that help reduce depression. There are community communication benefits that we know are really important just starting conversations in your neighborhood about how to grow food more sustainably or about healthy diets. So, there’s all of these potential benefits to gardening. And then what I also in general, gardens tend to be managed more sustainably than large scale farms.
And there are things people can do to manage them even more sustainably if they want to, going back to our building soil organic matter theme, you can do that at home as well. You can grow a cover crop in your garden or apply compost that’s made from home or yard waste. So there’s lots of things that people can do to increase sustainability at the individual level. But I should also point out, from my perspective, there are some limitations as well that we have to keep in mind. An individual gardener, currently, in the US probably can’t grow most of their staples unless they’re a full time farmer. So things like grains and beans.
And so if we really want to deal with this issue of the global food environment and affecting people’s food choices. Then we’re going to have to have those things happening in tandem, right? More gardens alongside changes to food and agriculture policy. » Sure, yeah, that’s super helpful. So many people are starting to talk about sustainable diets which kind of sit at this intersection of better for the environment and better for your health. And have a lot really interesting kind of overlapping domains and areas of expertise involved. Can you tell us, from your perspective, what is a sustainable diet and where do you see this leading us in the future? » Yeah, the sustainable diets concept is really useful.
The general definition is a diet that meets dietary guidelines for long-term human health while avoiding degradation of natural resources and the environment. So we’ve been talking earlier about the role of crop diversity and how important it for improving environmental sustainability, well, crop diversity is also linked to dietary diversity. And that’s a key component of a sustainable diet. So in general, it’s understood that a more diverse diet is important for disease prevention and general human health. There are new, more expanded definitions of sustainable diets that include aspects like cultural acceptability, economic affordability, and access.
And general speaking, our definitions of food security have also expanded in recent decades to think not just about food ability or even economic and physical access to food. But also the quality of food, and then the quality of our diets for human nutrition. So this is an important concept that’s gaining a lot of recognition. It’s now part of several national dietary recommendations. So many countries in Europe have adopted it, and it’s also being used in Brazil. So it’s appearing more and more on these international policy agendas. So the issue is thinking about how we might get there from here. How do we actually have policies that support sustainable diets? We really need interdisciplinary approaches to do that.
So there is growing calls for, what we call, a social ecological systems research approach. That essentially says, food is both social and ecological. So we need people tackling this issue from many different angles. So thinking about ecological approaches to food production. But also the social realm like political and institutional constraints to food security in very different contexts. And also these social issues, like equity and access to resources, that also really affect who has access to a sustainable diet. And then this is also filtering into the international agenda through the UN’s Sustainable Development Goals. So the second Sustainable Development Goal is called Zero Hunger. And it links targets for sustainable agriculture with targets for food security.
So that’s a really innovative direction to go. And I think in order to actually achieve that, we need to think about changes on the ground that involve changing policy. But also coordinating efforts from all of these grassroots movements that are talking about this issue. Whether it’s issues of farm workers rights or restaurant worker rights. What else, food justice, food democracy, local food, right, you hear all of these different terms out there. And basically, that means that we need to coordinate rural and urban interests which have been sort of artificially separated in recent decades as we’ve become more and more urban.
But to fully tackle this issue and realize policies that get us to sustainable diets, we’re going to have to have all of those diverse voices at the table. » That’s a really great way to end the conversation. It sounds like kind of starting to connect those dots. Bring down the silos and start kind of bringing in interdisciplinary, multidisciplinary teams to about these issues in the future. While at the same time encouraging folks to go out and get their hands dirty and plant a garden. » That’s right. » Awesome, well, thank you so much for joining us today, Jennifer, and- » Great, thank you. » Thank you all for joining us.
We hope that you jump into the discussion forums and continue to speak with your fellow learners. And we’ll see you in the next segment.

In this segment Jennifer Blesh and Benjamin discuss how insights from the field of ecology can help us build a sustainable future food system. You will learn about the size and the scope of the agriculture sector’s contribution to climate change and what lessons we can learn from ecological science that may help us manage and change our current practices around food production. We will also talk about issues of food policy, ecological insights into backyard gardening, and the concept of “sustainable diets.”

Jennifer Blesh is an Assistant Professor in the School for Environmental Sustainability and an affiliate of UM’s Sustainable Food Systems Initiative. She is also the Principle Investigator of the Soil and Agroecosystems Lab at the University of Michigan. Full Bio Here.

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