Industrial scale agriculture suffers from yet another problem. Soil degradation. Declining soil quality is not just a problem in the global south. It is happening all around the world. In Europe, about 12,5% of arable land is estimated to suffer from moderate to high erosion. This is equal to an area larger than the entire area of Greece. At the University of Copenhagen, Christian Bugge Henriksen is trying to help farmers with this challenge. My name is Christian Bugge Henriksen. I'm associate professor and research group leader of the climate and food security group here at the University of Copenhagen. We are working on sustainable food systems, with a focus on food production, but also covering the entire food value chain. We are also focusing on the transition towards less meat and more plant-based diets. I am currently involved in the Horizon 2020 project LANDMARK, and in this project, I'm leading the development of the soil navigator, which is a decision support tool for agriculture, for farmers and advisors, that will advise them in how to optimize their soil functions. The drivers behind the issue are many. We are working on soil, because we are currently facing a number of threats to our soil resources. These threats include population growth, urban expansion, pollution, climate change and unsustainable management practices. All these threats are drivers of soil degradation. Erosion is one of the central types of degradation. When the soil is eroded by either wind or water, it may lose 75% to 80% of its organic matter content, and also its nutrient content, with consequent release of carbon to the atmosphere. With lower carbon content, the soil will also lose its ability to hold and supply water for the plants. Another consequence can be a decrease in soil biodiversity. Heavy machinery can cause yet another type of soil degradation, as it compacts or seals the soil. Finally, acidification and soil pollution are additional contributors to soil degradation. All in all, the different types of soil degradation can impair the five basic functions of the soil: Primary productivity is the capacity of the soil to provide food, fiber, feed and energy. Nutrient cycling is the capacity of the soil to receive, store, supply and recycle nutrients. Water regulation and purification is the capacity of the soil to remove harmful compounds from the soil and also to supply sufficient water for the crop use. Habitat and biodiversity is the capacity of the soil to provide a habitat for a wide range of soil organisms. The carbon sequestration and climate regulation function is the capacity of the soil to store carbon in a stable form, mainly as organic matter, and also to reduce net greenhouse gas emissions, including CO₂, nitrous oxide and methane. The Soil Navigator system, that Christian has been a part of developing, is built up around precisely these five functions. In the LANDMARK project we are developing the Soil Navigator decision support system. The Soil Navigator will assist farmers and farmer advisors in maintaining long term sustainability and soil fertility. Whereas other agricultural decision support systems focused mainly on the yield and nutrient management - the Soil Navigator will work on all soil functions simultaneously. In the Soil Navigator we have then developed decision support models for each of the five soil functions. We have established teams of experts to develop the models, based on the input data that the farmer or the farmer advisor gives on the farm, and this is both in terms of the soil and the management and the environmental conditions. The Soil Navigator's data input inform about many different aspects of the soil. This means that the farmer can get specific recommendations from the system: First the farmer provides data on how the farm is managed. So, whether it is managed organically or conventionally, what amount of tillage that is applied, what kind of crops that are grown if there's a crop rotation, if there are any catch crops, what kind of fertilization is used and so on. Then the farmer will also need to provide data on the soil. What type of soil is it? Is it a sandy soil or a loamy soil or more clay soil. And also, if the farmer has input on soil measurements. What is the nitrogen level in the soil? What is the carbon content in the soil? If there any measurements of earthworms, the farmer will also be able to enter this data. Finally, also the Soil Navigator by itself extract information about the climatic conditions, from weather stations, and the farmer can go and correct this data, if he has more precise data. So this is the first step of the navigator - it is to input the data. So, based on this input the Soil Navigator will then assess the initial status of all the soil functions, so the farmer will be able to see, for each of the soil functions, if they have a low, medium or high level. And based on this assessment, the farmer will then be able to decide for example, if we have a very high primary productivity, a rather good nutrient cycling, but quite low climate regulation. Maybe, the farmer wants to increase the climate regulation, and he can then indicate this in his priorities, and run the Soil Navigator again to optimize the soil functions. Based on this, the Soil Navigator will then come with very specific recommendations, for how the farmer can increase the climate regulation on the farm. This could for example be, by increasing the number of the crops in the crop rotation, it could be, by implementing more catch crops in the crop rotation, and it could also be, for example to reduce the nitrogen input to avoid nitrous oxide emissions, and also to reduce tillage. So there can be many different recommendations, that will be very specific depending specifically on what data the farmer has provided. The Soil Navigator is financed through the EU Horizon 2020 program. More research innovations like this, are needed if soils shall retain their fertility, and continue to supply the food we need, in the coming decades.
