Bio-Waste & Agriculture #1: Soil Health & The Carbon Quest
Transcript from the Episode
Camille Duran (CD): At a time where there is so much buzz about the circular economy, increasing recycling rates, and activating “the bio economy” across Northern Europe, there is a tension in the system and that is more and more visible. And of course, we HAD to cover this issue – and it may get a little bit uncomfortable for some people in the region – but that’s ok – because we’re not here to judge, we’re just trying to get things moving in the right direction.
Let’s dive in.
You’re listening to The Green Exchange.
Part one of our series about Bio-Waste & Agriculture: Healthy Soil and Carbon quest.
HEALTHY SOILS, AGRICULTURE AND THE CARBON QUEST
CD: You know when you have two problems that can actually solve each other?
For instance you have a sock with a hole because too often you forget to cut your big toe nail and it ends up making a hole in your sock – and that’s one problem. On the other hand you need something to protect your golf clubs… Well you just need to introduce your old socks to your golf clubs – and there you go!
You get the idea.
It’s a little bit the same with our topic today. We have two problems that could solve each other. The two first episodes of this new series will help us set the stage. I will take you through two short chapters – one at the city & one at the farm – and we’ll start a discussion from there.
First off – we go to the farm. This first chapter is called ‘Healthy Soils & The Carbon Quest’.
I should clarify that in the following segment, we’re talking about the regions of Scandinavia where agriculture is the most intensive: So southern Sweden, southern Norway, pretty much the whole of Denmark, Finland also have some highly productive regions.
Denmark is probably the most interesting because of the role that food production plays in the economy. Not only the arable land covers more than 60% of the territory, but the country is also known in Europe for its intensive approach to growing grain, for its 22 million pigs, large dairy farms and very influential cooperatives. We can keep that in mind.
So what’s this first problem?
The problem with intensive agriculture and what became ‘conventional farming’ is that it seriously degrades the soil. And it’s putting our food production system in danger. I’m sure you’ve heard about this, right?
I am taking you to a place where agriculture is probably as intensive as it gets.
We’re talking to Dan Noble, he is one of the good guys over there, and one with great expertise and vision, his group is trying to make ‘healthy soils’ mainstream.
CD: Hello Dan, how are you?
Dan Noble (DN): Hi Camille, I am great. how about you?
CD: Very good. Dynamite, thanks for being with us.
CD: Dan, for the record, you’re the Executive Director of the Association of Compost Producers in California. Your focus is on renewable carbon management which includes the formation a portfolio of products made from organic feedstocks & organic residuals of all types.
DN: And we’re looking at the economic and industrial development of the whole bio-products economy in California but of course in interfaces with the U.S. and globally.
CD: We’re talking about a complex issue here so I am going to add a few comments & sounds as we go so we don’t lose anyone, okay?
CD: But tell me, first question, what’s the problem in the way we treat our soils in most intensive agriculture models?
DN: Well the main problem is that we have developed a method of aerating the soil, which involves tillage, and the use of synthetic fertilizers.
CD: To clarify, tillage is used to aerate the soil and degrade whatever organic matter happens to be left over from the previous crop cycle. It sounds like this:
[SOUND OF TILLAGE]
DN: And while it does aerate the soil, it tends to destroy and oxidize the Soil Organic Matter and in addition to that, if the soil left fallow and not planted with cover crops specially over winters and during rainy seasons, and there’s often more erosions and soil loss during the winter.
CD: Right, and all these are very serious issues here as well. Okay so tillage degrades the soil and you also mentioned synthetic fertilisers which are “man-made” inorganic compounds – usually coming from by-products of the petroleum industry. It can be applied to the fields in a solid palletised form or liquid form – which is even more energy intensive.
DN: The question is, “How are we going to manage the nitrogen cycle, basically the fertilizer cycle in the soils?” And that’s where organic farming comes into play.
CD: And last time we talked, you were explaining how our fertilising practices are unsustainable. I try to explain: We add just a few macronutrients to the plant when fertilising (like Nitrogen, Phosphorous and Potassium, NPK), and we and forget all the micronutrients that are also needed, plus we tend to kill the biology in the soil. And last but not least, Dan, I leave it to you…
DN: There is a net carbon loss in the soil.
CD: So, good transition to my next question: How do we define a healthy soil?
DN: The basis of what is called healthy soil is to have high Soil Organic Matter, meaning total soil carbon. A healthy soil is usually a compliment of a high amount of organic matter, but then in addition to this organic matter is the form of nitrogen and the nitrogen is staying in the soil or whether it’s running off or polluting ground water or surface water, which is of course throughout the world.
CD: And it definitely is a problem here at Scandinavian farms… Here is the very important question: Can we say that with conventional fertilising practices we cannot build healthy soil?
DN: Well that’s absolutely true. Conventional fertilizers do not include carbon. Period.
CD: Well I hope this is clear to everyone now… [Laugh]
COMPOST VS. SYNTHETIC FERTILISERS – DO WE HAVE THE FEEDSTOCKS WE NEED?
CD: Ok so we know tillage is doing damage, releasing carbon into the atmosphere, we know synthetic fertilisers, in addition of being synthetic and energy intensive, obviously don’t do the job because they return just the macronutrients, and we know that if you want your soil to be healthy, you need proper amounts of Soil Organic Carbon. I go slow here and I recap here because all this is fundamental.
By the way, we have produced a whole episode about this last year. It’s called “Increasing Soil Organic Carbon in the Öresund Region”, we are just re-contextualizing here to bring everyone up to speed so we can advance the discussion. Check it out in our favourite podcasting app or in our websites. It is a little bit more detailed about this specific issue. Our guest in that previous episode was John Wick, the Carbon Farming Guru from the Marine Carbon Project in California. And if you remember, here is what he told us:
John Wick: So the system is crashing, degraded. We’ve lost carbon, so what we are talking about is simply starting a restoration of previous carbon levels. The most available form of carbon is biologically stable form which is compost. It is a biologically stable carbon-nitrogen complex. That goes into the soil in a plant absorbable rate, different than fertilizer; different than manure and so here we have a material that is stable.
And we know the profile of the emissions to create it where when the soil system is dusted with it, we don’t ever turn it or till it, we dust it in half inches, not much, quarter inches even less. A quarter inches of dusting of compost and from then on that system starts taking carbon in. This is not a big idea, it’s simple. We are just giving back a little bit carbon that has been lost.
CD: So compost seems to be the product of choice; it is a carbon-nitrogen complex that is biologically stable, you can simply dust it on the land, just a thin layer, available at a plant absorbable rate, and from then on you’re rebuilding your soil. We’re just starting to realise the true potential of applying compost to the land on a large scale. There are couple of products that are starting to appear and we will talk about those as well. And I can already hear a couple of objections coming from the farmers. Hang on to it, we’re going to discuss this in length.
Dan, back to our discussion to finish this first chapter…
CD: What are the bio materials – or feedstocks I should say – that we should consider for producing compost or other organic amendments?
DN: Well in the paper, we divide the feedstocks into five different categories. Biosolids, one that is already mentioned, which is basically processed human manure. along with the other waste that happens to be present there. The other is of course food scrap, which is kind of the new thing, and you have done a lot of programs on that.
There’s the green material that comes from the landscapes and also the woody materials that either comes from landscapes, agriculture or forest by-products. So that’s high-cellulose.
The green material, the more green it is, that means the more vegetative or protein material it has available in it. And then of course, there’s all the ag[riculture] residues, both the plant residues, from crops, crops residues, or when you tearing down an orchard that has passed its time, or bush plants or vines; there can be woody material or green material in there. Of course, with every crop there can be green material, either be tilled in or used as animal feed and of course lots of agricultural crops are also animal feed crops, so that means you are feeding lots of animals and then you have a huge amount of manure.
CD: Ok, so at any moment animal manure is collected already, we can access that.
Bio solids, human manure – that’s creating a little bit of discussion but there are some interesting projects going on, and we’ll probably dedicate a whole episode to that topic in the coming few months.
Woody materials coming from forestry waste, we know how to access that, although a lot of it is going to biomass – that’s another story. But really the two material streams that are becoming increasingly interesting are green waste coming from gardens, parks and landscapes, and food waste, coming from your kitchen! And why are they becoming so interesting? Well because they are going to become widely available… How come? This is for our second Chapter: We called it “The Wonderful World of EU Recycling Targets”. And we’ll publish this part in a few days. Stay tuned.
I’d like to thank The Organic Stream for making this episode possible. The Organic Stream is an international media channel covering all topics related to the organic material value cycle: soil health, bio-waste collection, composting, anaerobic digestion, sustainable agriculture etc. If you never heard Eleen Murphy before, go find The Organic Stream podcast in your favourite podcast app, or visits www.organicstream.org and check all their resources. Make sure…