Theoretical development of the SFRA model for the present day

In chapter 6, we applied SFRA for the first time to gain an understanding of potential agricultural development without inequality, using an historical counterfactual example in an advanced organic society. At a theoretical level, this enabled us to test the potential of socio-ecological modeling as a tool to develop sustainable scenarios from the standpoint of three living funds (the domestic unit, livestock and approaching soil biogeochemical cycles). As an exercise in applied history, moreover, it also helped us to grasp the key role played by the integration processes among different living funds that permitted the pursuit of strategies to minimize environmental and territorial impacts (Guzmán and González de Molina, 2009; Lemaire and Franz Luetbers, 2014; Marull and Tello, 2010). Today, these would be labeled as ecofunctional intensification strategies (Schmid et al., 2009), but they have a strong value of biocultural inheritance lost amid the processes arising from the Green Revolution (Agnoletti and Rotherham, 2015; Altieri and Toledo, 2011). As noted in the previous chapter, however, the initial SFRA remained limited as an historical and contextual exercise and because of the shortcomings of linear approximation and their assumptions.

In this chapter, we propose moving forward with the SFRA to consider new elements.

Our aim is to apply SFRA to current farming systems in order to identify agricultural scenarios that are feasible, technically viable and desirable. To do so, it is necessary to review how the general structure of the model is established at the scale of agroecosystem. Once again, the initial elements of the socio-ecological model are self-reproducing living funds.

We return to the three groups of living funds that are fundamental to an agroecosystem:

people, domesticated species and non-domesticated species. Based on these groups, we characterize five more or less distinct living funds, namely: society and agrarian community (people), livestock (domesticated species), soil fertility and also a proxy for farm-associated biodiversity (non-domesticated species), following the structure of funds set out in chapter 2 (figure 2.2).

Figure 7.1. Modelling diagram for the SFRA for 2009. Source: Our own. Squares represent fund elements while arrows fluxes. Black lines are the models’ structure while labour and fuelwood are not considered constraints. Dashed

lines refer to the objective function.

Chapter 7. Possible horizons of agroecological landscapes, SFRA for 2009

We address the reproductive requirements of these funds by means of the flows presented in Figure 7.1. To ensure reproduction, we take an agroecological perspective in terms of meeting the needs through biophysical flows and not by importing external inputs (Gliessmann, 1998), except for the application of labor as indicated in section 2.1. We will perform an approximation of the organic flows involved in the system.

Since we are studying a dynamic system in non-equilibrium, it is fundamental to establish a time dimension, which would logically be annual given the characteristics of farming, as assessed in Chapter 6. The extractions to be made of a fund at an annual time-scale, therefore, must be sustainable and the return of flows for the maintenance of the fund should also be sufficient to begin the following year without having been degraded.

A last key question to address in the new approximation of the SFRA is the unit of analysis, given that the farm scale used in the previous chapter does not make sense in current societies. We are considerin here the ability of the territory to feed the whole society and not restricted to the previous domestic units. In agronomic or bioregional models, the unit of study is defined in terms of watersheds, topographical units or bioregions based on biotic composition (Dodge, 1990). However, for a socio-ecological model to make sense, the units of analysis need to be representative of historical cultural interactions. As a result, it is necessary to identify an appropriate agroecosystem scale from the viewpoint of socioeconomic exchanges, transport and coherence as a bioregion. In light of our limited sources, time constraints and the amount of available information from the four municipalities in the Vallès county, we will again consider the same unit of analysis used in chapters 3 and 4.

Below we present the basic features of the funds considered in the SFRA, looking at their composition, their interaction with other living funds and the limitations in the model’s development. The SFRA must be subject to potential evolutions in the range of technological and agronomic options and any proposed modifications that follow from the establishment of a dialectic with the wishes and interests of society, i.e. through its deliberation. The model that will be applied as an example, therefore, must be understood as flexible because new elements can be introduced for consideration at any time, as shall be seen, for instance, in the case of sewage sludge.

2.1 Agrarian community and society

In this case, the aim is to apply SFRA to an industrial society, which has a level of complexity in productive social relations that is much greater than in the mid-nineteenth century.

Agriculture now plays a minor role in terms of employment, given the impacts of the Green Revolution. Agricultural labor productivity has risen from 67 GJ/h to 650 GJ/h, giving rise to a profound shift in the production matrix (see chapter 4). In 2010, employment in agriculture for the European Union 27 was a little over 5% of total employment (EUROSTAT, 2010). The challenge has now become how to supply food to the entire society and not only to farmers, while also ensuring that the needs of the other living funds are met.

It has been amply demonstrated that the mechanization of farm activities is one of the bottlenecks in the loss of energy efficiency in farming systems, and that the current high dependence on fossil fuels makes it unsustainable in the long run (Leach, 1975; Pimentel et al., 1973; Tello et al., 2016). Nor can it be ignored that mechanized farming has resulted in a major social advancement, minimizing the most physically taxing activities of farmers. Whether drawn by animals or driven by steam, electricity or fossil fuels, machinery has brought an unquestionable improvement to the living conditions of farming communities (Martínez Alier, 1987).

Whereas in the case of the other self-reproducing funds we hold that an agroecological transition should promote the functioning of the funds strictly based on biophysical flows, a

Chapter 7. Possible horizons of agroecological landscapes, SFRA for 2009

complex and underdeveloped debate in the field of social metabolism is left open here. The degree to which mechanization is sustainable lies beyond the object of our study. Without denying the interactions that it supposes with the SFRA model³¹, therefore, we will consider a degree of mechanization similar to the current level as a first approximation.

Another modification since 1860 is the disappearance of the flow of fuelwood as a constraint in the agroecosystem. This is due to the change in the energy matrix caused by the socioecological transition from an organic society to an industrial one, in which biomass now represents 2% of total consumption, with an estimated potential contribution of 9% (Codina and Koua, 2015; FAO, 2013; Institut Català de l’Energia, 2009). Because of limited access to certain sources on the potential of biomass use, we do not include this flow in the present paper.

As for flows from society to the agroecosystem, there are two main sources of resources, which we considered in the SFRA c.1860: the use of domestic residues and the re-use of human excreta. In the current context, we will make two distinct assumptions by type of resource. For domestic residues, we will include only the return of composted materials from foodstuffs produced in the territory in order not to estimate imports of nutrients external to the agroecosystem. As well, despite they were used in traditional organic societies for feeding livestock at the farm level, in this case we will consider them for restoring nutrient cycles to soil.

In the case of human excreta, which was fundamental for the closure of nutrient cycles in traditional organic societies (Tello et al., 2012), a vigorous debate revolves around the effects of their use on agriculture. Because of the risks associated with the presence of heavy metals, organic components such as pharmaceutical wastes, and a lack of knowledge about the potential processes of increased antibiotic resistance from the application of sewage sludge, it is advisable to adopt a precautionary principle that must yet be validated or rejected based on scientific findings (Bouki et al., 2013; Smith, 2009a, 2009b; Wuana and Okieimen, 2011). As a result, the flow of human excreta is not used in the agricultural metabolism for the SFRA in 2009.

2.2 Livestock fund

The role of livestock in agroecosystems has changed significantly as the integration among living funds has declined (chapter 4). In this SFRA, we propose recovering at least the function of providing fertilizer materials and the role of such animals in taking advantage of resources that do not compete with human consumption.

We distinguish three categories by the type of food that they can supply and by their current functions within the agroecosystem:

a. Monogastric animals for meat consumption: basically pigs³²

b. Monogastric animals for meat and egg consumption: chickens and hens.

c. Ruminant animals for meat and milk consumption: historically, the characteristics of ruminants have been critical for sustainability because of their metabolic ability to make use of fibrous materials (Krausmann, 2004). Basically, we can distinguish sheep, goats and cattle.

31 A proposal to return to animal traction would affect livestock, while a proposal to recover traction with fuelwood would affect land-use.

32 Rabbits and horses are also monogastric animals, but they have a much greater capacity to consume forage and grasses than pigs. Because of this reason and because of their extremely low consumption in today’s diets (MAGRAMA, 2009), we do not consider them in the model, nor do we include them in the first group. Their substitution for pigs is not as directly proportional as it would be among the types of poultry in the second group, for example.

Chapter 7. Possible horizons of agroecological landscapes, SFRA for 2009

For the applied SFRA, we select a representative animal species from each group, with the understanding that there should be a possibility of substitution (to a large extent, if not absolutely) with any other animal of the same group. In the future, if the study should incorporate the possibility of animal traction, these groups would need to be modified in order to make distinctions on this dimension as well.

2.3 Soil fund and farm-associated biodiversity

Similarly as in the previous SFRA, here we will approach the satisfaction of the biogeochemical cycles through nutrients balances as a proxy of the mantainment of good conditions for soil fertility (González de Molina et al., 2010; Hendrix et al., 1992). A good ecological condition of the soil will correspond to any practices that are carried out at the plot level, not merely the biogeochemical cycles because we are not including dynamic analysis of nutrients inside soil. While it is obvious that the organic amendments being considered here will promote better conditions for physical and biological fertility, the model does not capture their effect, but rather that of biogeochemical cycles. However, as we are focusing at landscape level we deem enough only considering them for this approach. At the same time, a further change from the previous SFRA will now be to incorporate nutrient balances in forest land so that sustainable agricultural processes are not supported by their degradation.

For this new case application, we will also include a constraint regarding material conditions for farm-associated biodiversity. The problem when dealing with farm-associated biodiversity is that is distinct from domesticated species because, as we already stated, it cannot simply be supplied a set amount of food and a barn. So in order to develop a fund-flow analysis implies much more complexity.

At the same time, biodiversity has several levels, so that any agroecological approach should be planned at various scales (de Groot et al., 2010; Gliessmann, 1998). At the scale of plot, there is the alpha biodiversity, which is always lower in farmland than in undisturbed land, although agroecological practices can mitigate the gap. As we are working at the scale of agroecosystem, however, what interests us is beta biodiversity, which concerns aspects of the landscape (Gliessmann, 1998).

One of the important conditions for the provision of these services is the structure of land covers, which is an emergent property of the landscape (chapter 3). The leap from the farm scale to the regional scale enables us to take into account how the different distributions of farms independently affect the emergent properties of the landscape, which also require planning (Cong et al., 2014; de Groot et al., 2010). As we mentioned, we will limit the analysis to biological aspects in this SFRA. That is, we will focus on the material conditions left to species that can provide specific regulation services, such as pollination and pest control, or cultural services, such as the intrinsic value of the associated biodiversity. As indicated further on, in the current approximation we will incorporate landscape patterns.³³