Sustainable City Farming in the Oosterwold: An
Interdisciplinary Research
Noud van der Ven, Martijn de Vries & Max Frings University of Amsterdam
Abstract. In the bottom-up structured area of Oosterwold in which the inhabitants
are responsible for the development of the area, creating a sustainable city farming system proves to be a challenging task. In order to be sustainable, this system has to reduce the environmental burden, be economically viable and socially acceptable. This study will analyze the difficulties and opportunities facing the bottom-up structured area of Oosterwold in developing a city farming system whilst simultaneously conducting an interdisciplinary analysis on what type of city farming is most beneficial for the area. It has been found that reducing the environmental burden is inversely related to the economic viability. Additionally, although the governance structure is properly arranged, more participation of the inhabitants is required in order to create a properly functioning city farming system.
Index
Index 2
Introduction 3
Theoretical Framework 4
Maintaining Soil Quality 4
Economic Viability 6
Social Acceptance 7
Research Problem & Research Question 7
Research Problem 7 Research Question 8 Complexity 8 Interdisciplinary Approach 9 Yield 9 Labor 9 4 Farming Methods 9
Methods & Data 10
Yield Potential 10
Economic Production Function 11
Social Dimension & Spatial Rules 12
Results 15
Aquacrop Model 15
Economic Production Function 18
Economic Viability 18
CBNRM Analysis 20
Spatial Rules on City Farming 22
Conclusion 22
Discussion 23
Recommendations 24
Literature 25
Appendix A: Soil Description 29
Appendix B: Economic Production Function 31 Appendix C: Interview with Stefan Poot 37
Introduction
Throughout human history, the shaping of landscapes has shifted from a bottom-up approach, overseen by local inhabitants, to top-down policy, guided by city planners, project developers and politicians (Reps, 1965). The Oosterwold project in Flevoland, The Netherlands, aims to shift the power of shaping your surroundings back to individuals, allowing the people that are going to live here to shape an area of 4.363 hectares as they seem fit (Gebiedsteam Oosterwold, 2018b). While only having to apply to 10 rules, which provide a basic framework around how the landscape should be organized (Gebiedsteam Oosterworld, 2018a). Therefore, it is a unique place in the Netherlands where 15,000 household are set to be built according to this bottom-up approach. One of the 10 principles states that city farming has to be an important feature of the area:
“Meer dan tweederde van het oppervlak van Oosterwold zal groen zijn en ecologische kwaliteiten toevoegen aan het gebied. Er is plaats voor vele soorten groen, zoals landbouw, bos, recreatiegebieden en moes- en siertuinen. Deze verschillende vormen van voedselproductie zijn onderdeel van het zelfvoorzienende karakter van Oosterwold.” (Gebiedsteam Oosterwold,
2018c).
This implies that the inhabitants will have to develop a sustainable food provisioning system that also has social, environmental and sustainable benefits (Gebiedsteam Oosterwold, 2018a). Developing such a system in Oosterwold is challenging for various reasons. There is no central planner or developer and the inhabitants responsible for the development do not possess all the relevant knowledge needed to construct a sustainable city farming system (Lekkerkerker, 2016). Additionally, if the development of the city farming system is to be deemed sustainable it must simultaneously reduce the environmental burden, be economically viable and socially acceptable at the same time (van Mierlo et al., 2010).
This study will analyze the difficulties and opportunities facing the bottom-up structured area of Oosterwold in developing a city farming system. Hereto, a framework that takes sustainable city farming as its focal point and integrates the three dimensions (environmental, economic, social) will be used. The first dimension will make sure that long-term soil quality is maintained whilst the potential crop production remains constant. Subsequently analysis of the costs related to production will ensure the economic viability of city farming. Lastly, in making sure that the farming practices are in accordance with local spatial planning rules and that the system satisfies the preferences of the local residences, the difficulties regarding the bottom-up structure will be analyzed.
The integration of these three dimensions of sustainability will yield an understanding of the potential implementation of city farming in Oosterwold. Our goal is to identify a spectrum of city farming methods that can be implemented, for which every method the extent to which they comply with the three dimensions of sustainability is described. The inhabitants can use this information to compare potential successful city farming methods in line with their preferences.
This report will elaborate on the theoretical framework that integrates the three dimensions of sustainable city farming, after which the research question and objectives will be indicated. Subsequently, an explanation on the integration and research methods will be provided. Lastly, the results will be presented, followed by the conclusion, discussion, and recommendations for further research.
Theoretical Framework
Maintaining Soil Quality
Environmental sustainability will be assessed by the concept of soil quality, since this term encompasses most aspects that are vital processes in a sustainable farming system, Doran and Zeiss (2000), defined it as:
“The capacity of soil to function as a vital living system, within ecosystem and land-use boundaries, to sustain plant and animal productivity, maintain or enhance water and air quality, and promote plant and animal health” (p.1).
These characteristics of soil quality can be found in the framework for the evaluation of soil quality made by Karlen et al. (1997), the most cited article for soil quality evaluation. Therefore, this framework for soil quality evaluation will be used as a guide in developing a sustainable city farming system in Oosterwold. Karlen et al. (1997) state that soil quality consists of three major components: plant and animal health, environmental quality and sustained biological activity. These components depend on the 10 soil quality indicators as defined by the authors in the table below.
Indicators of soil quality and some processes they impact
Measurement Process affected
Organic matter infiltration Nutrient cycling, water retention
Infiltration Runoff and leaching potential, erosion potential
Aggregation Soil structure
pH Nutrient availability
Microbial biomass Biological activity, capacity to degrade pesticides
Forms of N Availability to crops Bulk density Plant root penetration
Topsoil depth Rooting volume for crop production Conductivity or salinity Water infiltration
Available nutrients Capacity to support crop growth
Through literature research, four farming methods were found that influence all soil quality indicators in the table above: no-till agriculture, intercropping, crop-residue management and the implementation of Arbuscular Mycorrhizal fungi.
The indicators of infiltration, aggregation and bulk density can be improved by No-till agriculture. This is defined as as farming systems without the practice of tilling (Niggli et al. 2017; “Bulk Density” 2018; Karlen et al. 1994).
Preferred forms of N without the need for chemical fertilizer use in combination with a healthy layer of organic matter can be realized by intercropping, which is defined as growing different kind of crops in close range to each other. The intercropped species can help to sequestrate nitrogen without fertilizer use (Vandermeer, 1992; Stern, 1997; Eaglesham (1981).
Crop-residue management, a farming approach which leaves crop residuals on the field, improves the soil quality indicators of organic matter, infiltration, aggregation and microbial biomass (Collins et al. 1992).
The implementation of Arbuscular Mycorrhizal fungi manages the pH in the soil and increase the amount of nutrients available to plants (Islam & Katoh, 2017; "Mycorrhizal Fungi and pH of Soil or Water" 2018).
A sufficient topsoil depth is the result of a constant influx of organic matter in combination with minimal mechanical or human disturbances in the field which mixes soil layers in order to give the topsoil time to develop (Thompson et al. 1991). Another secondary benefit of the influx of organic matter is the improved conductivity (Helling et al. 1964).
At last, a healthy aggregate stability is a by-product of an organic layer, which protects the underlying layers for erosion (Franzluebbers 2002; “Aggregate Stability” 2018).
Figure 1 on the next page presents an overview into which soil quality indicators are influenced by the four different farming methods.
Figure 1: an overview of the 4 proposed farming methods and the soil quality indicators they improve. It shows the relationship between the four concepts of the farming systems, and the soil quality indicators they improve.
Economic Viability
After making sure that soil quality is maintained in Oosterwold, the economic viability of the sustainable city farming system is a crucial dimension as well since the costs and risk inherent in developing a system like this could potentially rise too high if this aspect is not properly analyzed. With high costs and low benefits, a system is not feasible and therefore studying the economic viability is much required.
In setting up the analysis of this dimension, a different approach has been used relative to conventional economic methods for several reasons. Firstly, most economic frameworks for measuring economic viability are rooted in utilitarianism, assuming that decision-makers make choices that maximize well-being (Mankiw & Taylor, 2014). To measure economic viability then, is to focus on welfare maximization (Snyder & Nicholson, 2012). By doing so, many different factors that affect human well-being can potentially be valued and included in the analysis. Problematic with this method is that many relevant factors have in the past been proven difficult to quantify (such as soil quality, personal preferences, or cultural heritage) leading to exclusion in decision-making processes (Bateman et al., 2011). Furthermore, the goals of city farming in Oosterwold include not only food production but also participation, short-chains and circularity (Gemeente Almere & Zeewolde, 2014), are not easily compatible with conventional economic models. Several assumptions underlying these models, such as perfect competition, perfect markets and profit maximization are violated (Mankiw & Taylor, 2014) and thus another approach is needed. Thirdly, most conventional models try to fit all variables in to one monetary value to compare the efficiency of various policies (see for example Barbier & Heal (2005); Bateman et al. (2010); NRC (2015)). In Oosterwold however, the decision makers are the inhabitants whose primary concern cannot be the efficiency of the system. In situations like this, another measure of economic viability that does not combine all variables into one monetary measure will provide more insights for the decision makers (Wegner & Pascual, 2011). Thus, in line with the other
disciplines involved in this study, the economic framework is a pluralist framework with different variables and indicators highlighting different costs and benefits of sustainable city farming, as opposed to conventional economic frameworks that put everything in one monetary value.
Studying the economic viability of city farming in Oosterwold in line with a pluralist framework as argued for above, requires a clear formulation of what variables are relevant and related to it. Since limiting the environmental burden is a prerequisite according to the principles of Oosterwold, the earth scientific research already assumes that practices must be ecologically sustainable. Therefore, non-sustainable practices do not have to be included in the economic production function and hence, the information on agricultural practices, soil quality and output (yield) is obtained through and in collaboration with earth scientific research. This can be seen in figure 1 where yield, based on soil quality and sustainable agricultural practices, enters the economic production function. Subsequently, the costs related with the outputs of different agricultural practices will be calculated. This includes estimating the time required for inhabitants to put in city farming and the cost of capital. The cost of capital contains the investments in physical capital (e.g. tools, seeds, fertilizers, etc.) required for crop production. This way, the production function will inform the inhabitants about the risk associated with setting up the city farming system.
Social Acceptance
Finally, sustainable city farming also has a social dimension (Mierlo et al. 2010), because besides its economic viability and the maintenance of soil quality it should also be socially acceptable. This means that the chosen method of sustainability should also be adopted and recognized by anyone which may be involved. Besides the social dimension of sustainability, city farming in the Oosterwold should also be organised in a bottom-up approach. This is another social aspect which should be researched for an assessment of the Oosterwold. In order to study the social sustainability and bottom-up approach the CBNRM method can be used. This method is a good fit as it analyses how a community can organise themselves in a bottom-up process to manage a resource. Thirdly there is a specific way of city farming for the Oosterwold which incorporates rules and frameworks, by studying these we’ll be able to overlook the boundaries which apply to city farming for the Oosterwold. By studying policy documents, articles, and websites this will lead to a theoretical framework which includes these three components.
Research Problem & Research Question
Research Problem
The development of a sustainable city farming system in Oosterwold poses various challenges. First and foremost, the bottom-up structure is a quite novel way of area development and is thus accompanied by unclarity regarding the responsibilities for management and maintenance (Lekkerkerker, 2016). When determining that the inhabitants are responsible for the entire development of the area, it becomes clear that educating them will be vital to the success of sustainable city farming, because for the development of a geographical area to be deemed sustainable it must simultaneously reduce the environmental burden, be economically viable and socially acceptable (van Mierlo et al., 2010). From the theoretical framework it follows that each of these dimensions and their related disciplines face their own challenges. In the earth scientific research, due to limitations of time and resources, experiments into the effect of the proposed farming methods on the soil quality indicators cannot be measured. Instead, proposed methods are based on literature research, but not specific to the Oosterwold area, thus the extent to which the soil quality indicators will be affected remains unclear. Subsequently, to be economically sustainable, the output (yield) has to be high enough relative to the cost of production in order to be viable or even feasible. Then there are also the social challenges as city farming should manage itself entirely in a bottom-up approach. This means that potentially thousands of people have to cooperate in providing feasible city farming for themselves and each other with as little guidance
as possible. Since all the lots are closely connected to each other and contain city farming for the most part the mutual influences can’t be denied. Therefore, the social dimension and sustainability is important as there are many potential challenges they have to overcome together.
Research Question
Thus, to analyse the potential of city farming in the bottom-up environment of Oosterwold, this research will set out to answer the question; what are the opportunities and shortcomings of sustainable city farming in the Oosterwold area by using their specific bottom-up approach? The division of sustainability into three dimensions is represented by the following sub-questions:
- What crops can be grown in the Oosterwold area while maintaining soil quality? - What type of city farming is economically the most viable in Oosterwold?
- What are the social and spatial characteristics on the specific bottom-up approach to city farming for the Oosterwold?
Complexity
Where the three disciplines in this study face challenges of their own, their combination in an interdisciplinary research forms an even more complex system. This is very much needed though, because the Oosterwold system is a complex system itself; diverse ‘agents’ (inhabitants) are interconnected in living together and thus form a network. They self-organize since there is no central planner, leading to unpredictability and emergent phenomena where the outcome or direction of the system is hard to predict or to reduce from local actions taken by the inhabitants. At the same time, small choices can have big effects. Consider for example the outcome of an inhabitants that decides to manage the city farming organization. Furthermore, city farming clearly linked with nature which is in itself a complex system due to the various dynamics that are at play here (Menken & Keestra, 2016).
In combining earth scientific, economic and spatial planning research, this research aims to capture the complex city farming system in Oosterwold, though there will inevitably be limitations as to what this research can capture. The most important limitation of this study is that, for practical reasons, the research follows a pluralist framework in which variables based on different assumptions and methods from different disciplines are represented. Consequently, the results of this research will also be presented in an overview separating the different variables from different disciplines. Hence, this research has an informative aim instead of trying to predict the eventual development or outcome of city farming in Oosterwold. Additionally, the development of complex systems is better supported by management focussed on experimentation and agility (Boulten & Allen, 2007), so analyzing and representing the dynamics at play in Oosterwold within the pluralist framework aids this purpose.
Although the pluralist framework aimed at informating the inhabitants has practical benefits, the complex nature of the city farming system of Oosterwold will still be represented in this research, predominantly in the overlap between the disciplines. Some concepts related to variables are applicable within more than one discipline but have different meanings and implications within them, as can be seen in figure 1. The next paragraph will elaborate on the integration techniques applied used to combine these overlapping concepts in the interdisciplinary research.
Interdisciplinary Approach
The previous sections show that sustainability consists of an economic, social and environmental dimension. Since sustainability plays a major role in the approach to city farming for the Oosterwold the three dimensions have been translated into three disciplines which are indicated with the coloured circles in figure 1. The findings of the three disciplines can therefore provide a conclusion for sustainable city farming as a whole since the three dimensions of sustainability are being researched. To do so the previous sections provided theories and concepts from the standpoint of each discipline which are indicated with the yellow blocks in figure 1. The research structure as shown in figure 1 is the multidisciplinary basis of our research. However, this section will elaborate on the interdisciplinary potential of this research since there are linkages between the concepts which are used for the different disciplines.
Figure 2 below, shows a more comprehensive research model that also reveals the interdisciplinary side of this research which can be found in the overlapping areas between different disciplines. How the concepts in these overlapping areas are integrated to the disciplines is as follows:
Yield
The concept of yield is a central part of this research, since the amount of yield that can be expected influences the three dimensions of sustainability (figure 1). Higher yields positively influence the economic viability, but also have implications for the environmental sustainability and social acceptance, since each farming methods realizes a different yield but also requires another approach to its implementation regarding spatial rules.
Yield is used very differently in earth scientific and economic research. In the former, it purely represents the amount of yield measured in some quantitative metric that a certain type of agricultural practice can obtain. In economics, normally a price is attached calculated as well that can be combined with the quantity to represent output in a monetary value. This difference is overcome by the pluralist approach elaborated on in the framework and problem description. Hence, the conventional economic concept of output has been transformed to fit the earth scientific concept of output measured in some quantitative metric. What remains different is the value attached to outcome. In economics, a low output relative to related costs will be seen as inefficient and probably unwanted, whilst in earth science, low output is not necessarily unwanted if for example soil quality is maintained.
Labor
Labor is an important variable for the economic production function. It represents a cost for inhabitants that is related to participating in city farming. In economics, labor is measured in time so that it can be compared with the labor requirements for other practices. The social research has a different scope on labor as the focus is on the organisation of labor. For this research the social side of labor will be researched in terms of its effectiveness of the approach to labor organisation. The CBNRM method will be used to see if the bottom-up approach is being organised in an effective way, if this is the case this provides a better environment for successful labor organisation. The goal here is to integrate both concepts to labor which are quantitative as well as qualitative findings to transform the concept of labor in broader terms.
4 Farming Methods
In the theoretical framework of earth science 4 methods of sustainable farming are being discussed. However, not every type of agriculture is allowed in the area since there are rules included in legal frameworks and the zoning plan that apply to the Oosterwold. These rules and laws provide restrictions to the possible farming methods in the area and therefore shouldn’t be overlooked. Secondly there are rules to what extent city farming makes up a part of the Oosterwold, this is different to every type of lot in the area. Incorporating this data into the model for farming methods
will result in a more precise estimation for the yield of every method. In terms of integration this can be seen as ‘organisation’ as the rules and laws that apply provide an arrangement and organisation of the different farming methods for the Oosterwold (Menken & Keestra 2016).
Figure 2: The interdisciplinary framework combining the three dimensions of sustainable city farming (environmental sustainability, economic viability and social acceptance). Represented in yellow: key concepts. Represented in white: indicators. Represented in purple: underlying concepts.
Methods & Data
Yield Potential
In order to analyze what crops would be most suitable to grow in the Oosterwold area while maintaining soil quality, two soil samples were taken. These samples were analyzed and classified using the FAO World Reference Base. The standardization of the soil samples is needed to implement the data in an Aquacrop model simulation in order to determine yield responses.
Three different scenarios, each with a different combination of farming methods were analyzed. All farming methods use the concept of no-till, the first scenario is coupled with CRM, the second with CRM and intercropping, the last with CRM, intercropping and AMF. The maintenance of soil quality will be analyzed using the 10 soil quality indicators by Karlen et al.
(1997), crops and management practices will be chosen in accordance the 10 indicators. Lastly, the outputs of the potential crop yield in Aquacrop simulation will be given in kilograms per hectare per year. These numbers will be put in the economic production function in order to assess the related costs and economic viability of the different scenarios.
The Aquacrop parameters were set in order to most accurately mirror the conditions in the Oosterwold area. Potato was the crop of choice since they have been successfully farmed on clay soils in the Flevoland area (Uien en aardappelen de zekerheden van Flevoland 2018).
Two sets of different crops for three scenario analyses were conducted, each comprised of a different set of farming methods. The two crops that were analyzed are potatoes and sugar beets, since these are two of the most successful crops in Flevoland and available in the Aquacrop model (Staps, 2016). The first scenario, in which no-till and CRM are applied. The second scenario, for potatoes: an intercrop system with maize, for sugar beets: an intercrop system with faba beans (El-Dein, 2015). The third scenario, implements AMF besides above-mentioned farming methods.
Fertilizer input is required in all scenarios, as the University of Idaho points out, potatoes need 247 kg nitrogen, 33.6 kg phosphorus and 336 kg potassium per hectare (Moore, Stark, Brown, & Hopkins, 2009). Sugar beets need 120 kg nitrogen, 110 kg phosphorus and 160 kg potassium per hectare ("Crop Nutrition"). In the second scenario, the intercropped system with potatoes and maize facilitates improved nitrogen uptake, thus reducing the need for nitrogen fertilizer to 100 kg per hectare, a reduction of 59.5%, according to Haque, Hamid & Bhuiyan (1994). For sugar beets intercropped with faba beans, only 75% of the nitrogen fertilizer is needed to obtain an optimal yield (El-Dein, 2015).
The third scenario, AMF facilitates improved uptake of phosphorus by plant roots, reducing the need of phosphorus fertilizer with 14.5% to 28.7 kg per hectare (Bolan, 1991).
In order to represent the farming methods in Aquacrop, different field management inputs (.MAN files) were chosen. For no-till, no field management was chosen, as no management is the equivalent of no tillage. To represent CRM, the presence of organic mulches was integrated into the model, using the file “ExampleMulch.MAN”. To represent the situation where all ten soil quality indicators are met, as in the third scenario when AMF are integrated into the system, the file “ModerateSF.MAN” was used, which influences the Aquacrop model in such a way that soil quality is not a limiting factor for yield anymore.
Scores for soil quality were given on the basis of how many soil quality indicators (table 1) were positively influenced by the farming methods.
At last, a conversion for calorie yields per hectare were calculated, in order to gain insight into which crops yield most potential energy for the inhabitants.
Economic Production Function
After establishing the yield for different scenarios and crops, the analysis of the economic viability of sustainable city farming in Oosterwold requires several variables and indicators to calculate the related costs with the economic production function (see table 2). Firstly, to calculate the labor costs (time costs) associated with the given level of output, data on labor requirements for the chosen agricultural practices will have to be collected. Important here is that this needs to be corrected for the lower efficiency level of the inhabitants of Oosterwold relative to large-scale agriculture. The investment in physical capital (cash costs) required for city farming can be calculated according to standard account practices. Firstly, it is important to determine what type of physical capital is required (e.g. seeds and fertilizer). Subsequently data will be required on the price and quantities required, to use simple accounting theory for estimating the investments required.
Table 2: The different variables of the economic production function; cash costs and non-cash costs (time) make up the total economic production function and the total cost of production.
Social Dimension & Spatial Rules
In addition to the analysis of the yield potential and its economic viability, qualitative data will be used in our analysis in order to supply context specific data of the Oosterwold area to add qualitative data besides the quantitative data used in the other studies (Bryman, 2008), this is especially important for the case of the Oosterwold since it is unique with its bottom-up approach to city farming. This approach to city farming has two sides, the social side being the specific bottom-up approach of the Oosterwold. And the other side is the spatial characteristics of city farming. To assess the aspects of a bottom-up approach to city farming both the social and the spatial effects need to be researched.
Social Dimension
To research the social aspects of a sustainable bottom-up approach to city farming the community based natural resource management (CBNRM) method will be used. A frequently used definition of this method is:
‘‘CBNRM aimed to create conditions under which most members of the community stood to benefit from the sustainable utilization and management of resources. This would occur through a bottom-up participatory approach. …. CBNRM attempts to integrate the goals of conservation, sustainable development, and community participation’’ (Milupi, Somers, & Ferguson, 2017, p. 1)
This definition of CBNRM fits the sustainable bottom-up approach to city farming for the Oosterwold very well. Firstly, the resource can be described as the land used for city farming. Secondly, the bottom-up participatory approach being the ‘people make the city’ approach of the Oosterwold. Thirdly, the sustainable utilization and management includes the social dimension of sustainability. Therefore, CBNRM can be used as an all-embracing method to research the social aspects of city farming.
The CBNRM method was introduced in the book ‘Governing the Commons’ by Elinor Ostrom (1990). The method was proposed to overcome the depletion of common-pool resources (CPR) as described in the famous article ‘The Tragedy of the Commons’ by Garrett Hardin (1968). Ostrom (1990) described how communities can organise themselves to achieve mutual agreement for governing CPRs through 8 design principles as shown in table 3. To operationalise these 8
design principles the SESMAD (Social-Ecological Systems Meta-Analysis Database) methodology will be used in this research (Dartmouth, 2018). This methodology translates each design principles into one or two questions with corresponding answer types to each outcome of a question. This methodology seems a good fit as there is hardly any literature on conducting a CBNRM analysis. Secondly, this methodology provides the necessary steps to research each design principle. And thirdly, this methodology is already used in eight peer reviewed articles (Dartmouth, 1990).
Ostrom’s design principle SESMAD question Type of
variable Answer types
Clear boundaries that define the rights of usage and access to the common-pool resource.
Are there clear rules that are followed about who and who isn't a member of the Oosterwold?
Ordinal No boundaries Unclear boundaries Clear boundaries
Clear boundaries that define the rights of usage and access to the common-pool resource.
Are the boundaries that define the spatial extent of the Oosterwold clearly defined and highly visible?
Ordinal No boundaries Unclear boundaries Clear boundaries Conflict-resolution mechanisms need
to be in place for as well as being accessible and low-cost.
Are mechanisms in place to address conflicts that arise over the use of this resource by the users?
Binary Yes/No
The users themselves engage in monitoring the quality and quantity of the resource.
How much environmental monitoring of the resource do the users engage in?
Ordinal Low Moderate High Users have the right to set up
organisations that make decisions regarding the resource without being challenged by higher authorities.
Within this governance system, do larger governmental jurisdictions recognize the autonomy of lower-level jurisdictions, and their right to make decisions regarding the resource?
Ordinal Low – no recognition, Moderate – some recognition,
High – complete recognition
Nested governance, the governance system contains multiple levels that recognise each others legitimacy.
Does this governance system contain multiple levels, with each level having a set of actors who conduct tasks with respect to the management of this commons? If so, is there active coordination across these levels, or not?
Categorical Single-level governance, Coordination among multiple levels, Multiple levels but no coordination
Collective choice arrangements, all the users can participate in changing the rules.
How high is the level of participation of this actor group in the process that determines how the resources are being governed?
Ordinal Low Medium High Congruence between the users
regarding costs, benefits and restrictions.
Is there general proportionality
group members incur and the amount of benefits received?
The users themselves engage in monitoring the quality and quantity of the resource.
Does this actor group monitor its own activities with respect to the use of the resource?
Binary Yes/No
Graduated sanctions, violating rules can be assessed with penalties.
Are sanctions applied by and to the members of this group for violations of rules regarding extraction or emission? And if so, are these sanctions graduated?
Categorical Graduated sanctions, Non-graduated sanctions, No sanctions
Congruence among users regarding costs, benefits, rules, goals and restrictions.
To what extent do the institutional arrangements of this governance system fit well with the ecological or physical features of the commons on which they are implemented?
Ordinal Low Medium High
Table 3: Ostrom’s design principles and corresponding SESMAD questions which both are adapted to fit the case of the Oosterwold (Ostrom, 1990; Dartmouth, 2018)
Spatial Dimension
The spatial side of this research will focus of the spatial possibilities and rules for city farming in the Oosterwold. The Oosterwold had specific rules which apply to city farming, by analysing these in combination with basic rules that apply to the zoning plan we’ll be able to assess the boundaries for city farming in the Oosterwold. To gather this information, we’ll be looking at policy documents and zoning plans for the Oosterwold. The gathered information forms the foundation for the farming methods since they determine what methods can and cannot be used. Therefore, it is important in making a selection of possible methods to research in the potential yield analysis.
Results
Aquacrop Model
The Aquacrop model provided insight into expected yields for the different crops and scenarios, each scenario and crop had different fertilizer requirements, as shown below.
Table 4: Potato yield per scenario.
Table 4 shows the yield potential for the three different scenarios using potato as the crop. The first scenario, using no-till and CRM yields 1284 kg/ha, the scenario that implements no-till, CRM & intercropping yields 2029 kg/ha and the scenario that implements all four farming methods yields 2167 kg/ha.
Table 5: Potato fertilizer requirements per scenario.
Table 5 shows the fertilizer requirements for potatoes, it is clear that the nitrogen requirements significantly drop from 247 kg/ha to 100 kg/ha when intercropping with maize is applied in the second and third scenario. Also, a slight drop from 33.6 kg/ha to 28.7 kg/ha in phosphorus requirements can be seen in the third scenario due to the introduction of AMF. The potassium requirement stays constant at 336 kg/ha throughout all scenarios.
Table 6 shows the yield potential for the three different scenarios using sugar beet as the crop. The first scenario, using no-till and CRM yields 1302 kg/ha, the scenario that implements no-till, CRM & intercropping yields 1927 kg/ha and the scenario that implements all four farming methods yields 2592 kg/ha.
Table 7: Sugar beet fertilizer requirements per scenario.
Table 7 shows the fertilizer requirements for sugar beets, again, intercropping reduces the nitrogen requirements from 120 kg/ha to 90 kg/ha, the introduction of AMF reduces the need for phosphorus fertilizer from 110 kg/ha to 94 kg/ha. The potassium requirement stays constant at 160 kg/ha throughout all scenarios.
Calories per kg for the analyzed crops are 767 kcal/kg for potatoes (USDA, 2018) and 430 kcal/kg ("Beets, raw Nutrition Facts & Calories", 2014).
The three scenarios have different scores for soil quality, No-till & CRM realize 7 out of 10 soil quality indicators, No-till, CRM & Intercrop realize 8 out of 10 soil quality indicators and the implementation of all four farming methods realizes all soil quality indicators.
Economic Production Function
For each scenario given above with a certain yield, an economic production function (such as in table 3) has been set up including an elaboration on the chosen parameters (see appendix B). A general elaboration on how the values of the variables are determined is provided here after which the results will be presented. It is important to stress that there are numerous limitations to the economic variables and estimates. An in depth elaboration on this is provided in Appendix B.
Variable Determination Elaboration
Seeds 𝑝𝑠 ∗ 𝑞𝑠 Total seed cost is equal to the seed price (ps) times the seed quantity used.
Fertilizer 𝛴[𝑝
𝑖 𝑓
∗ 𝑞𝑖𝑓] Total fertilizer cost is the sum of the price (pf) of a certain type (i) times the amount of fertilizer used (qf) of a certain type (i).
Time 𝑌/𝐿 Total time cost is equal to the total yield (Y) in kg divided by the average labor requirement (𝐿) per kg.
Table 9: Explanation of the determination of the variables in the economic production function. For limitations of the variables, see Appendix B.
Economic Viability
After gathering the required data, the economic production functions yield the following results. In table 10, the costs per scenario in €/ha is shown for when potatoes are planted. The cash-costs include the cash-costs of purchasing the main crop seeds and the required fertilizers. Since adding more farming practices reducing the fertilizer requirement, cash-costs decrease a little bit when practices are added.
Table 11 shows the labor (time) cost per scenario in minutes/ha/household when potatoes are planted. For the first scenario, 19,08 minutes are required, followed by 40,92 minutes and 61,14 minutes.
Table 11: Time cost per scenario per household for potatoes (assuming 15.000 households).
Table 12 shows the cash-cost per scenario when sugar beet is planted. Again, only the costs for the main seeds and for fertilizers is included and therefore costs decrease when farming practices are added. The costs are a lot lower due to lower seed costs.
Table 12: Total cash-costs including the main seed and fertilizer cost per scenario for sugar beet.
Table 13 shows the time cost per scenario in minutes/ha/household when sugar beet is planted. For the first scenario, 18,72 minutes are required, followed by 26,22 minutes and 73,14 minutes for the second and last scenario respectively.
Table 13: Time cost per scenario per household for sugar beet (assuming 15.000 households).
CBNRM Analysis
In table 14 the results of the CBNRM analysis are shown. The information to answer these questions was provided through an interview with Stefan Poot who was a project manager in the area for over a year.
Question Answer
Are there clear rules that are followed about who and who isn't a member of the Oosterwold?
No boundaries Unclear boundaries
Clear boundaries
Are the boundaries that define the spatial extent of the Oosterwold clearly defined and highly visible?
No boundaries Unclear boundaries
Clear boundaries
Are mechanisms in place to address conflicts that arise over the use of this resource by the users?
Yes
No How much environmental monitoring of the resource do the users engage in? Low
Moderate
Does this governance system contain multiple levels, with each level having a set of actors who conduct tasks with respect to the management of this commons? If so, is there active coordination across these levels, or not?
Single-level governance
Multiple levels but no coordination
Coordination among multiple levels
Within this governance system, do larger governmental jurisdictions recognize the autonomy of lower-level jurisdictions, and their right to make decisions regarding the resource?
Low – no recognition,
Moderate – some recognition,
High – complete recognition
How high is the level of participation of this actor group in the process that determines how the resources are being governed?
Low
Medium
High Is there general proportionality between the amount of costs group members incur and the amount of benefits received?
Yes
No
Does this actor group monitor its own activities with respect to the use of the resource?
Yes
No
Are sanctions applied by and to the members of this group for violations of rules regarding extraction or emission? And if so, are these sanctions graduated?
Graduated sanctions
Non-graduated sanctions No sanctions
Table 14: The SESMAD questions with the corresponding answers.
The Oosterwold did very well on most of the subjects in the analysis. Starting off with governance and organisation, the area has a well-established multi-level governance system. The highest authorities are the municipalities of Almere and Zeewolde, followed up by the area director and the board of the area. Besides those there is an increasing number of associations that specify in different services and functions for the area. At the lowest level there are the users of the Oosterwold which can organise themselves or use their individual say in managing the resources and services. Currently the bottom-up structure works with a ‘beeping system’, this means that only a higher level of governance will interfere when it is notified by multiple users about a certain problem. Only if the users themselves cannot deal with an issue, or if it is more efficient to deal with it at a higher level, it is being escalated to that level. This method ensures the bottom-up approach so that changes and organisation begins at the lowest level. Organisation among users is already happening as there are currently users collaborating with building roads for example. Regarding city farming there is not much collaboration going on, possibly because most people are now focussed on finishing their houses. However, in the last stage of this research a new initiative on city farming emerged which plans to create a dedicated square for trading foods and sharing knowledge regarding city farming (Appendix C).
As city farming is still at an early phase in the Oosterwold, the engagement, participation and monitoring by users is at an early phase too. These are likely to increase simultaneously with the development of city farming, but this is however not by default. As Ostrom (1990) describes the engagement of users at an early phase is a critical success factor as this is one of the key differences that can prevent them from going down the road of the ‘commons’. There are however, some examples of user engagement, mostly on the correct implementation of city farming as the interpretation on the practice is varying among the users. That user engagement is important also becomes clear on how water quality is being managed in the region right now. Most of the users have to treat their sewage themselves since there is no sewerage in the area. Since the treatment is not very effective, the treated water that is being dumped into water bodies and ponds is declining the water quality over time. The water quality is decreasing towards the legal norms and therefore collective action is required. If the users would have engaged with managing and monitoring the water quality earlier on they could have acted earlier on without the involvement of higher levels of governance. This illustrates the necessity of early user engagement in monitoring, usage, and participation on a common pool resource, which is the most important conclusion from the CBNRM analysis (Appendix C).
Spatial Rules on City Farming
In the Oosterwold there are different lots with different requirements regarding city farming, leisure and building. The average of all these different types of lots should dedicate 60% to city farming (Gemeente Almere, 2016). Regarding city farming the zoning plan does not state any rules on the practice. A different policy document that is dedicated to city farming describes the requirements and their definition on city farming. However, this document does not state any rules regarding the use of fertilizers or different farming practices. It rather describes the goals and some examples of city farming. Since city farming should aim for circularity this could restrict the usage of fertilizers, there are however no clear rules that restrict it. The four farming practices as described in this research fit the definition of city farming by the Oosterwold as they aim for circularity and to preserve the soil quality (Gemeente Almere, 2014). In the policy document the definition of city farming is summed up as:
‘‘City farming can be defined as the production, processing, and marketing of food (and related products) in and around the city. …. City farming is multifunctional and has many forms of appearance. City farming is mainly about food production, but also aspects such as social cohesion, participation, care, education, short (food) chains, sustainable energy and closing cycles.’’ (Gemeente Almere, 2014, p. 2)
This definition is mostly very common and is very similar to a very popular definition used by Orsini, et al. (2013, p. 700). However, the policy document expands on the social aspects a lot further as it is allowed to meet the requirements of city farming as the initiative contributes to the social cohesion without producing any foods. Therefore, this definition allows that playgrounds or campings can account for city farming which have nothing to do with farming. While discussing this definition in our interview the project manager said that this definition is more likely to cause confusion than creative initiatives which may be a cause of city farming staying behind in development (Appendix C). In addition, there is no trajectory or deadlines that the users have to follow regarding city farming which enables the users to delay their initiatives.
Conclusion
In order to facilitate a sustainable city farming system in Oosterwold, implementing more sustainable farming practices contributes to higher yields and better maintains soil quality for both crops studied. However, at the same time this significantly increases the labor costs related to city farming. Thus, there is an inverse relationship between reducing the environmental burden and the economic viability. quality and labor cost. This means that, if the inhabitants want to increase their
yield or better maintain the soil quality, it will cost them more time. Over time, by expanding and including more users with city farming the social and economic costs and benefits will become more apparent to the users. As labor increases in relation to city farming the social organisation of labor will increasingly be challenged. Regarding the governance and bottom-up approach to labor, those are likely to withstand the test of time as those are well-organised and functioning in the area. However, participation and collaboration by users is still at an early phase. Those are likely to increase simultaneously with the expansion of city farming, these are however not correlated and therefore should not be overlooked as city farming increases. Regarding the rules and approach of city farming this research found that there are not many rules that specifically apply to city farming in the Oosterwold. The four farming methods used in this research fit well with the approach and definition of city farming in the Oosterwold. However, in policy documents the definition of city farming is widely broadened to include social initiatives, e.g. a camping or playground, as city farming. This ambiguous definition is causing misunderstandings about city farming and therefore it delays the initiatives by the users.
By dividing sustainable city farming into environmental sustainability, economic viability and social acceptance this research showed the interdependence of these three concepts. Each field of research is equally important in achieving sustainable city farming. The interlinkages and recurring concepts between the fields of research prove the interdisciplinary nature of researching sustainable city farming.
Discussion
Limitations to the farming methods and Aquacrop model
This research has a several limitations. First of all it has been assumed that farming methods have to be sustainable since one of the principles in Oosterwold is that it has to be green. Therefore, the four farming methods chosen are only a variety of possible methods and thus, the results represent a comparison between those methods. Furthermore, the Aquacrop simulation yields results can be very different from actual yields, due to decentralized farming systems, no professional knowledge and other crop choices. Moreover, Aquacrop parameters were set to most closely mimic the situation as in the Oosterwold area, however, no Aquacrop precipitation and groundwater files were available for that area, so files that were available in Aquacrop which most closely resemble the situation in Oosterwold were chosen.
Out of the three scenarios used in the Aquacrop model, the scenarios that implement more farming methods show higher yields and comply with more of the soil quality indicators as compared to those that implement less farming methods. This suggests that the more time and energy the inhabitants are willing to invest into creating sustainable farming methods, the soil quality will be better maintained and higher yields can be expected. To what extent the inhabitants will be able to adopt the proposed farming methods of no-till, CRM, intercropping and the implementation of fungi will depend on how the inhabitants organize themselves surrounding the implementation of city farming, the availability of farming knowledge and the distribution thereof between inhabitants and the willingness to invest financial resources, time and energy. The economic production function deals with some of these issues, though it has several limitations on its own.
Limitations of the Economic Production Function
Most neoclassical economic models that are taught in the economics bachelor’s degree are based on assumptions of perfect competition, perfect information and perfect markets. In the economic literature review, it has been argued that these models are unsuitable for the Oosterwold area. In coming up with another way to analyze the economic viability of sustainable city farming, a pluralist framework has been chosen in order to be able to represent various economic variables that are relevant to the case. Though the economic production function used here does contain several
important costs related to agricultural production but not all possible costs. In economics, it is notoriously difficult to value everything that is of importance. The most important production costs have been included but other possible costs (e.g. taxes, land rents, depreciation costs) were not included due to the scope of the research. Another limitation of the research on the economic viability is that the only benefit related to city farming that has been included is yield. Inhabitants might realistically obtain a scala of other benefits from city farming such as esthetic pleasure, cultural values and social inclusion. These benefits have not been included because it was too difficult to value them. Lastly, there are a lot of limitations on the economic data since these are not widely available for city farming. These limitations have been included in Appendix B.
Limitations of Community Based Natural Resource Management
While working on the research it became clear that the city farming is still at an early phase in the Oosterwold. This made it hard to do an effective CBNRM analysis as a few design principles were not in place in the Oosterwold which may be in the future. Therefore, the analysis is limited to this point of measurement. When city farming would be further developed in the area it is possible to do a more in-depth analysis which enables a comprehensive review on every design principle. For this research this was not possible as all the concepts are new to the area and have to operate for a while to generate more data for the analysis.
Limitations on Interdisciplinary Research
Working together with three different disciplines also gave rise to some limitations. The theoretical framework provided a clear structure for the analysis, but difficulties arose during data gathering. For example, the economic production function required some data that the Aquacrop model did not provide, though it was assumed that it did. Some additional data was found through further research, but some relevant costs such as the cost of machinery and the cost associated with preventing soil degradation could not be included. Therefore, the inverse relation between reducing the environmental burden and the economic viability of city farming in Oosterwold might turn out differently if other costs related to city farming are included.
Furthermore, the overlapping framework of environmental sustainability and social acceptance regarded the spatial rules of city farming. However, the definition of city farming within the Oosterwold project is not clearly demarcated, making it difficult to draw conclusions about how space for city farming should be allocated.
Recommendations
Structuring city farming through a bottom-up approach is a new concept, for which research is not readily available. To overcome the limitations as specified in this paper, more knowledge and improved models are required. Firstly, the Aquacrop model is limited in its ability to represent the proposed farming methods. More complex agricultural modelling software which incorporates area-specific soil, groundwater, field management and climate data is needed to yield more accurate results. Furthermore, more research should be conducted into the labor costs of the proposed farming methods, in order to gain a comprehensive overview into the true economic viability of the different scenarios. Here we strongly recommend a close collaboration between earth scientists and economists due to the overlap between both disciplines. Proper collaboration would assist in discovering and representing the costs related to farming practices more clearly and completely. Further research into the possibilities and shortcomings for city farming in the Oosterwold area should inquire with local stakeholders beforehand. Since local knowledge about the difficulties regarding the implementation of city farming should be considered to direct new research into filling knowledge gaps, in order to fully benefit the area.
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Appendix A: Soil Description
Soil profile descriptions
In order to elaborately classify the two soil profiles the World Reference Base For Soil Resources 2014 is used in combination with the FAO Guidelines For Soil Description. The following four steps were taken for classification:
1. General site information 2. Soil formation factors 3. Soil description 4. Soil classification
a. Detecting diagnostic horizons, properties and materials b. Allocating the soil to a Reference Soil Group (RSG) c. Allocating the qualifiers
Soil profiles
General site information
Flevopolder, consisting of marine sediments.
Soil formation factors
Soil has been part of the ocean floor until 1962, since then the area has been dried until 1968, thus the soil is characterised by marine sediments. Since 1968 some vegetation, mainly grasses, started to grow on these soils.
Soil description
Fluvial deposits, as shown by the heavy marine clay found in the profiles. Some mottling can be seen due to oxidation and reduction. Oxidation and reduction have been present since the drying of the polder since 1962, since before that period the soil was fully submerged by the ocean. Grasses were abundant, around 50% of the soil surface was covered.
The horizon boundaries were as follows:
Ah: abrupt distinctness (0-2cm) with a smooth topography C: clear distinctness (2-5cm) with a smooth topography
Looking at the degree of erosion, it can be classified as moderate, since the field where the soil profiles were taken is flat and not protected and wind erosion is common, as well as erosion by heavy rainfalls.
The surface sealing is medium (2-5mm) with a Hard consistence, with fine, widely spaced surface cracks. The abundance of mottles found was common (5-15%), with a size class of medium (6-20mm). Its contrast was distinct, since they could be seen fairly easily.
The soil material adhered to thumb and fingers after applying pressure, thus it can be classified as
Detecting diagnostic horizons, properties and materials
Two horizons were detected, Ah layer and a C layer. The findings of the lower limit, texture, color and structure of the layers are shown in the table below.
Soil profile 1
Lower limit Texture Structure
Ah layer 3 cm Clay Loam Fine
C layer 60 cm Clay Fine
Soil profile 2
Lower limit Texture Structure
Ah layer 2 cm Clay Loam Fine
C layer 52 cm Clay Fine
Allocating the soil to a RSG
The presence of heavy clay deposited by marine sediments makes the soil a Fluvisol.
Allocating the qualifiers
