Tag: agriculture

The Interconnected Challenges of Nitrogen and Protein in the Netherlands – A broader Vision is needed for Spacial Planning including the Opportunities for Change!

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The Netherlands faces a confluence of two critical and interconnected challenges: the nitrogen crisis and the protein transition.These issues are symptomatic of a broader societal debate about land use, sustainability, and the future of agriculture. Contentious aspects include balancing the expansion of urban areas with preserving natural habitats, managing agricultural emissions while ensuring food security, and addressing the economic impacts of transitioning to sustainable practices. As I argued in a recent interview, the question underpinning these challenges is simple yet profound: what do we want our country to be?

Part 1: The Nitrogen Crisis – A Spatial Planning Issue

At the heart of the nitrogen problem lies the excessive emission of ammonia (NH₃), primarily from livestock farming. This has led to stringent government policies that have strained farmers, businesses, and broader society. As a physicist and modeler by training, I see significant flaws in how nitrogen models are used to guide policy. These models, while valuable as tools for monitoring and scenario analysis, have often been applied in a reductive and rigid manner.

One of the key failures is the lack of integration between disciplines. Decisions about nitrogen are deeply tied to spatial planning—an area where the Netherlands once excelled. My father, as part of the team that designed and developed Southern Flevoland, worked in multidisciplinary teams of engineers, urban planners, and sociologists. Their approach balanced long-term visions with immediate practical decisions. Today, such integrated thinking seems lost, in part due to shifts in governance that prioritize sectoral policies over interdisciplinary collaboration. Changes such as increased bureaucratic fragmentation and a reliance on short-term managerial goals have replaced the long-term, multidisciplinary approaches that once defined Dutch spatial planning. We rely on fragmented decision-making processes where jurists and managers dominate, often paralyzing progress.

The nitrogen debate exemplifies this. Policies have been reduced to calculations of critical deposition values (critical loads), which in turn narrow the focus to ammonia emissions. While these are valid considerations, they fail to address the larger question: how should we organize our land to balance agriculture, nature, and urban development?

Part 2: The Protein Transition – An Opportunity for Change

Parallel to the nitrogen crisis is the ongoing protein transition—the shift from animal-based to plant-based proteins. This movement is not just about sustainability but also about recalibrating our agricultural systems. Livestock farming consumes vast resources, from land to feed crops, while generating significant environmental externalities, including ammonia emissions.

The transition to plant-based proteins presents an opportunity to mitigate these challenges. For example, reducing livestock numbers could lower nitrogen emissions, freeing up land for other uses or more sustainable farming practices. Yet, this transition is not without hurdles. Plant-based protein products, such as meat alternatives, are often priced higher than their animal-based counterparts due to inefficiencies in scaling production, higher costs of raw materials, and underdeveloped supply chains compared to the well-established meat industry. These barriers must be addressed to make sustainable diets more accessible.

One potential solution is to implement policies that incentivize sustainable practices while disincentivizing resource-intensive ones. This could include taxes on meat and dairy products or subsidies for plant-based alternatives. However, such measures must be balanced to ensure they are socially equitable and do not disproportionately burden lower-income households.

Part 3: The Need for a Broader Vision

What ties these issues together is the need for a cohesive national vision for land use. The Netherlands is a small, densely populated country. Balancing competing demands for housing, agriculture, industry, and nature conservation requires a return to integrated spatial planning. The nitrogen crisis and protein transition are not isolated problems; they are symptoms of a larger failure to define and pursue a shared vision for the future.

Modern tools, such as scenario modeling and gamification, can support this process. For example, in Germany, scenario modeling was used to assess land use changes for renewable energy projects, enabling policymakers to balance ecological preservation with energy goals. Similarly, gamification tools have been employed in urban planning to simulate the impacts of zoning changes, fostering more informed community discussions. Imagine using interactive models to explore different visions for the Netherlands—from rewilding large swathes of land to creating high-tech agricultural hubs. These tools could help policymakers and citizens visualize trade-offs and make informed decisions.

Part 4: Moving Forward – A Holistic Approach

To address the nitrogen crisis and accelerate the protein transition, we must adopt a holistic approach. This means:

  1. Reintegrating Disciplines: Bring together scientists, policymakers, and practitioners to craft solutions that account for ecological, economic, and social dimensions.
  2. Redefining Metrics: Move beyond critical loads and ammonia emission levels to broader indicators of sustainability, including biodiversity, soil health, and societal well-being.
  3. Engaging Citizens: Foster public dialogue about land use and sustainability to build consensus around difficult trade-offs. Start a national discussion about the future of the Netherlands. What kind of country do we want to build?
  4. Leveraging Technology: Use scenario modeling and gamification to make complex policy decisions more transparent and participatory.

The nitrogen crisis and protein transition challenge us to rethink how we live, farm, and consume. Addressing these issues requires adopting a holistic approach: reintegrating disciplines, redefining sustainability metrics, engaging citizens in public dialogue, and leveraging tools like scenario modeling to guide decision-making effectively. By reconnecting these debates to the larger question of what kind of country we want to be, the Netherlands can turn these challenges into opportunities for innovation and progress.

“The Oversights in the Nitrogen Dossier Listed” – an explanation of the uncertainties and qualitative interpretation where nitrogen science still has some weaknesses. (See also the publication and discussion on Foodlog, December 12, 2023)

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Why is the nitrogen dossier such a protracted affair, and what can be done about it? Wouter de Heij, an engineer trained in Delft, was captivated by environmental issues from a young age. Now at 50, he shares his judgment on the scientific and administrative inadequacies in addressing nitrogen.

“Do you want to write a scientific paper on deposition? Or perhaps a report, and even better, a book?” These were questions I received regularly in recent years. Indeed, the dossier is so complex that an article quickly falls short. Should you start with physics, chemistry, biology, or ecology? Or with the (awkward) legislation? Or with collecting data for the models we use to calculate nitrogen? Or the models themselves? Or maybe with spatial planning, tackling it by freeing up environmental space for construction. Ultimately, nitrogen revolves around artificially added fertilizer and the question of how much environmental damage people are willing to allow to realize their living space within that of nature.

From almost every perspective or discipline, an explanation can be given for why there is so much attention on nitrogen.

Following on from “The Politics Must Learn to Dance,” in this text, I want to emphasize the science behind reactive nitrogen (the form that over-fertilizes nature) and explain how its dispersion works from the source that emits it. In a previous text, I introduced a conceptual framework on which I build here. I begin with a paragraph expressing my personal opinion, criticizing the messy way in which politics handles its policy tasks.

Afterward, I attempt to provide a rational and scientific interpretation of the physical aspects (emission, dispersion, and deposition) of nitrogen. Finally, I conclude with advice to policymakers and politicians on how to get the stalled situation back on track. A later text will be dedicated entirely to deposition.

My Political Opinion

As a child, I already heard about manure surpluses. As a teenager, I learned about acid rain. As a young student, I studied greenhouse gases and the ozone layer. This year, I turned fifty. Looking back, I believe that the Netherlands has made a mess of things.

We long believed that our country was “finished” and, as a result, we no longer engage in spatial planning. The current generations of civil servants and politicians work from tightly formulated coalition agreements and believe they can perform their duties through legal processes and influencing communication. There is no room for looking ahead based on vision, content, and discussion.

If I immediately zoom in on the nitrogen dossier from these remarks, I draw several conclusions. Scientific researchers and practitioners of their work should not have allowed a lack of budget for practical measurements. These same researchers should have been more humble and not rushed to a model as the best approximation of reality. There should have been incentives to motivate farmers and industries to continually reduce their emissions to soil, air, and water. Politicians and policy officials should not have believed in ‘silver bullets’ (such as focusing only on CO2 and nitrogen); moreover, they should not have handed over their task of governing the country and making policies to lawyers, judges, scientific institutions, and NGOs. We are wealthy Westerners in the penthouse of Maslow’s pyramid. Because we have the means, I believe we also have the responsibility to be frugal with our environment and to pass on our country ‘more beautiful,’ ‘cleaner,’ and ‘more prosperous’ to the next generations.

Background of Reactive Nitrogen

Since the discovery of fossil fuels and the Haber-Bosch process, which allows us to concentrate nitrogen fertilizer from the air using fossil fuels, we have been able to ‘create’ reactive nitrogen on a large scale and release it into the air. Especially in densely populated areas with a high density of people and livestock (such as the Netherlands, the Po Valley in Northern Italy, and the Ruhr area in Germany), you can observe the adverse effects on air quality. Nitrogen is primarily a local issue (within hundreds of kilometers) and operates on a relatively short time scale (from several to tens of years). In short, it concerns local (living) environments now and in the near future. In the Netherlands, we have experienced periods with mainly (too) much livestock. We are now entering a period with (too) many people. If we accept that but also want to maintain a clean living environment, there are two policy tracks: a) less activity (reduction), b) making existing activities cleaner (innovation); preferably while maintaining prosperity and employment in our country.

There are two types of reactive nitrogen. NOx, nitrogen oxides, mainly released during the combustion of fossil fuels in factories and vehicles, and ammonia. NH3, ammonia, is primarily released in livestock farming through the liquefaction of solid manure and urine. But there are also industrial sources of ammonia. In a barn, you can capture ammonia with, for example, a scrubber, assuming a perfectly sealed chicken coop or pigsty. Ammonia emissions can also be reduced by not mixing urine and manure or by feeding animals differently. Ammonia emissions in the Netherlands are mainly caused by ruminants (cows).

These numerous emission sources result in high concentrations of ammonia and NOx in the Netherlands, but this ‘blanket’ is not equally thick everywhere. The thickness of the blanket depends on the weather (rain, wind), the season, and the import and export of reactive nitrogen from the sea (ships and wind) or our neighboring countries (Belgium, with input from France).

With modern sensors, we can conduct point measurements that map NOx and ammonia concentrations. Satellites can give us an impression of the column concentration (a satellite looks two-dimensionally and can poorly measure differences in height). In addition, we can perform indirect measurements (consider soil acidity) or ecological observations on the ground and flora and fauna that correlate with nitrogen concentrations in the air. Finally, we can try to predict how reactive nitrogen spreads across the country (and to the ground and higher air layers) using computer models. The OPS model used in the Netherlands is a well-known example, a so-called CFD (computational fluid dynamics) model. CFD is a 2D and 3D approach widely used in the engineering world (FEM is another example). There are very few places at Dutch universities where students come into contact with FEM/CFD models since this skill is only relevant to a few science programs, especially at technical universities. In any case, it involves measuring or estimating the concentration of reactive nitrogen in the air.

Both types of reactive nitrogen, NOx and NH3, affect air quality, the health of citizens, and the quality of natural areas. However, the quality of natural areas is not solely determined by nitrogen. Temperature, drought, wind, soil quality, the presence (or absence) of phosphate and other minerals, and management play an equally significant role. I am still missing many factors. Ecosystems are dynamic and extremely complex. It is naive to look at them reductionistically. For this reason, I previously stated that models are the devil in the political system.

Uncertainties

Nitrogen emission, dispersion, and deposition may seem like a relatively straightforward field, but it is more complex than it appears. It consists of various disciplines, each with its own specialization. The involved mathematicians are seldom trained in biology. Ecologists have limited knowledge of dispersion models. Meteorologists lack insight into the complexity of ecology and biology. Lastly, soil scientists, for example, from Wageningen UR, are not adequately involved in the calculation models maintained by RIVM (Aerius).

There is considerable scientific uncertainty in six subtopics.

Firstly, the emission sources themselves are unclear. The actual situation regarding nitrogen sources, import, and export is unclear. In a chemical factory, you can measure the nitrogen concentration coming out of the chimney and multiply it by the emission flow to precisely determine it. This is manageable in a closed pig farm as well. However, in a pasture with cows or along a highway, this becomes much more complicated. How much nitrogen do we import via the air that was not emitted on Dutch territory? I suspect that the uncertainty margins of total emissions are in the tens of percentages.

The dispersion of components through the air. We cannot predict the weather accurately for even two weeks. The better we can predict the weather, the better we can predict the dispersion of components in the air, provided we know the emission sources well. Because policies work with average wind and rainfall, the margin of uncertainty is large. In the literature, this is estimated to be at least tens of percentages. Only the local nitrogen concentration seems to be fairly well predicted with models, as shown in the recent study by the University of Amsterdam.

The breakdown of reactive nitrogen by sunlight and UV in the air. Also, the precise processes of denitrification and nitrification in the soil. These are all dynamic chemical processes. Since these processes occur in a column upwards (the ‘z-direction’), and there is little to no measurement at greater heights, these are largely experimental scientific domains. There is simply not enough known about them. Satellites measure in a column in the ‘z-direction’ and cannot provide sufficient answers. Knowledge about these degradation processes is crucial but mostly overlooked.

Rain and wet deposition. Wet deposition can be measured by collecting rainwater and determining the nitrogen concentration in the rainwater. The monitoring network in the Netherlands is very small. Ideally, we should set up a few hundred measurement points per province. This is not complicated, not extremely costly, and offers the possibility to determine factual monthly data per location. Calculating with OPS is then no longer necessary and saves a lot of discussion about model errors that always need correction. Note that the fertilizing effect of wet deposition is only relevant when it rains, which occurs in the Netherlands about 7% of the time. Due to abundant rainfall, it is logical to expect that the share of wet deposition in 2023 will be higher than we think. I personally expect that the total actual deposition will turn out to be lower than the models calculated by RIVM.

Dry deposition. To get straight to the point: dry deposition is not directly measurable and can only be indirectly estimated and calculated. In the 1990s, considerable practical research was conducted. Around 2000, the monitoring network was virtually halted. There are about six so-called COTAG poles in the Netherlands. They conduct so-called flux measurements (from the last century) and calculate dry deposition through a model. I fear it is a theoretical black box with the appearance of real measurements, and I think working with biomarkers provides better measurement quality and meaningful model calculations. This is not cheap, but determining policy and monitoring the results of implementation without proper practical measurements seems unfair and incorrect to me. I have now read dozens of scientific papers and dare to conclude that the most commonly used models overestimate deposition by at least a factor of 2. I do not rule out a factor of 3 to 4. In a subsequent article, I will specifically address this shaky science. Dry deposition is the elephant in the room of nitrogen policy.

Soil activity and specifically soil chemistry. The soil is a dynamic phenomenon, perhaps even a dynamic equilibrium. Dynamic equilibria are systems where the concentration of a component in the soil is relatively stable, but there is still an influx and efflux. Wet deposition can also drain into deeper soil layers and flow back to groundwater without increasing nitrogen in the soil. Additionally, nitrification and denitrification also occur. Both processes are not included in Aerius. There is a broad call to take soil samples – I am not against it – but there must be a correct scientific interpretation.

All this makes the entire dossier a strange combination of legally strict laws and a scientific domain that spans many disciplines and is full of uncertainties. It is not an exaggeration to state that it has certainly slipped into a theoretical reality played out in computer models. Policy and goals have become detached from reality and are evolving far from practice. This should not be true, but it is. The nitrogen field can only grow well if there is sufficient budget for collaboration at multiple universities. The overly dominant role of RIVM does not contribute to the progress of the field.

Aerius, the Shell around OPS

In the media, much is often mentioned about the Aerius model. It is the graphical shell over the actual mathematical model with the aforementioned name OPS, as mentioned several times before. OPS calculates the concentration of components in the air. Aerius allows users to perform scenario calculations with OPS and estimate how much deposition according to the model ends up ‘on the ground.’ Whether this also happens in reality is, as I have already made clear, a separate matter.

Aerius uses a comprehensive list of emission sources as input (compiled via RIVM and WUR). This list includes all industrial users as well as farmers with their barns and the quantity of livestock. Practical research on emissions from livestock in barns was conducted at DLO (now part of WUR) decades ago; I am unaware of how often these have been modernized. In recent years, several errors have been regularly discovered in this emission list. The list itself is not entirely public due to privacy legislation (AVG), but I see no reason not to release the data for research. Only then can politics and science adequately verify whether the list is justified and relevant.

In addition to emission per source (expressed in mol of nitrogen per year per source), the heat capacity of the source and the height of the emission source (whether there is a chimney or not) play a significant role. OPS itself is best seen as a weather model; it predicts the convection of substances in the air and how they subsequently spread over (the surface of) the Netherlands. The emission source input is used to determine, via the model of a Gaussian plume curve, how high substances such as NOx or ammonia rise and how far they are then dispersed from the source in the air. OPS is, therefore, a model that tries to estimate the average concentration per point location of NOx or ammonia. OPS also includes a module titled DEPAC (DEPosition of Acidifying Compounds). This module then estimates the dry and wet deposition based on the concentration of ammonia and NOx as estimated by the OPS dispersion model, using a table. This is not particularly robust; I prefer to call it ‘weak science’ due to a lack of real data. Soon, I will address dry deposition measurements (which are almost non-existent) and how well DEPAC estimates dry deposition. Spoiler: not very well.

How about the Critical Deposition Value (KDW)?

I just explained that a lot is estimated without hard data. Aerius estimates, via OPS with DEPAC, the fertilization (dry and wet deposition) per hectare of nature per year. In Aerius, this hectare is called a hexagon because of the shape it has been given in the model. However, ecologists have also classified the Netherlands into similar hexagons, but based on the type of nature. Ecologists then determined at what total nitrogen deposition there are no risks, and above which deposition risks may arise.

The Netherlands has given the Critical Deposition Value (KDW) a role in laws and regulations. This is a risk norm and not a hard value. On the highways in the Netherlands, you can drive at 100 km/h (or slower), above that, you get a fine. That is a hard limit. This is not how it works with the KDW. Below the KDW, ecologists are convinced that – based on experiments in flower pots in a lab – there are no risks of changing the ecosystem. Exceeding the KDW increases the likelihood of changes. Only at very high deposition values do the risks increase if there is no nature management. The KDW is best compared to guidelines for drinking alcohol: between 0 and 1 glass per day, the risk is negligibly small, and above that, the risks gradually increase. But at 2 glasses, you won’t get sick right away; you really have to drink dozens of glasses a day and every day to get really sick. To put it simply and clearly: the experts at RIVM don’t know what a KDW means, while the ecologists who determine the KDW rarely know what Aerius/OPS calculates.

Policy Evaluation

If you look at the dossier from the perspective outlined above, you can hardly conclude anything other than that many clumsinesses have found their way into this dossier. The dossier is primarily legally stuck due to very strict laws and regulations that are scientifically on quite shaky ground. The dossier is also stuck due to the inability of the central government to make choices on spatial development (what do we want and do not want in our country). The nitrogen dossier has led to a blockade in the development of our country.

The next government can take three steps:

  1. Acknowledge that we have made a mess together. From there, a new step can be taken: reset the framework and existing Dutch regulations.
  2. Acknowledge that the Netherlands has a spatial planning issue and that the question is on the table of how we want to deal with so many people, activities, and ambitions in our small country. It may be that we have to take away the protected status of small pieces of nature, it may be that we need to handle immigration more consciously, and it may be that we need to create more high-rise buildings in the Randstad. It may also be that we need to reclaim a part of the North Sea. Anyway, this is a process where designers can provide visions, and thus the Ministry of Spatial Planning and the Environment (VROM) may need to be reinvented.
  3. Acknowledge that the use of a complex model like Aerius/OPS in granting permits or evaluating policies was awkward. Despite computers being faster than ever, policy should be made by people proposing rational ‘rules’ that can be adopted by our politicians (or not). Our democracy should not be handed over to Kafkaesque functioning computer models. In the nitrogen dossier, very simple policy guidelines can be formulated, for example: a) farms with livestock must be at least 500 meters away from nitrogen-sensitive Natura 2000 areas, b) we will implement an emission reduction program for all sectors, c) we will revoke the status of some nitrogen-sensitive Natura 2000 areas or invest extra in their management.