Agroecology to fight climate change

Agroecology is considered a traditional agricultural technique, but it has only gained in popularity in recent years in Europe. France has decided to become the leader of this field by promoting the technique and by implementing it in an experimental network of farms. This technique could be the one needed to make the agricultural system more climate resilient across the world, thus allowing humanity to combat climate change.

What is agroecology?

Agroecology is defined as:

the study of the role of agriculture in the world

However, scholars have pointed out that the definition fluctuates. It is considered a movement, a science or a practice in different parts of the world (Wezel et al. 2009). So, when talking about this notion, one can easily get confused.

In Brazil, agroecology is a movement that emerged in the 1970s to fight against the dependence of farmers on technologies such as GMOs and chemical fertilisers (Wezel et al. 2009).

In Germany, agroecology is a science that is applied on different scales (from the field to the landscape). It analyses ecological and biological processes on a site and then attempts to make use of those processes for the production of food.  Managing the ecosystem in this way allows for agriculture that does not rely on any chemical input (Wezel et al. 2009).

In France, agroecology is viewed as a practice that integrates ecological aspects into agriculture and focusses on the field level. It also has a social dimension, as it aims to create a network of farmers that can share their experience (Wezel et al. 2009).

What is happening in France?

In 2008, the French minister of agriculture launched a project that aims at promoting agroecology. One of its main goals is to reduce the pesticide use by 50% by 2018. This plan was revised in 2015 and the plan Ecophyto II emerged. This plan was implemented to reduce pesticide use by a quarter by 2020 and by half by 2025. The project has led to the development of a network of farms (DEPHY) using low amounts of pesticides and agroecological techniques (see Figure 1). In 2017, the network counted 3600 farms. Moreover, in 2014, the “law of the future for agriculture” (loi d’avenir pour l’agriculture) promoting ecological agriculture was established. This manifested the presence of agroecology in national law.

Screen Shot 2018-04-12 at 18.32.32.png

Figure 1: Distribution of farms from the DEPHY network

How can agroceology help to fight climate change?

As we all know, the agricultural sector will be hit by climate change. In areas where the crops are not near their maximum temperature tolerance, the increase of CO2 will help the sector and higher yields are to be expected. This situation is, however, temporary. With increasing temperatures and more extreme weather events, floods and drought are to be expected. Therefore, the yield will most certainly decrease in the long run (Altieri et al. 2015).

  1. A resilient system

Conventional agriculture is the most prevalent type of agriculture and promotes techniques such as monocultures (IPES-Food 2016). Monocultures are a simplification of the ecosystems and scientists claim that homogenous ecosystems are vulnerable to pest invasions and outbreaks. The expansion of monocultures leads to larger vulnerability of the ecosystems. Thus, it is urgent to add genetic and ecological diversity to agricultural fields. In regions regularly hit by extreme weather events (e.g. Asia, Africa, South America), farmers maintain the biodiversity of the field in order to cope with such uncertain conditions. Greater biodiversity in an ecosystem allows for species richness, which in turn allows for a large set of ecosystem services to be performed (functional diversity). Additionally, it allows for a larger range in responses to stress from the species performing similar ecosystem functions (response diversity). The response and functional biodiversity are the key to the resiliency of an ecosystem. Each species performs slightly different functions that might be redundant when the weather is mild. However, in time of harsh weather conditions, these redundant functions are the key to the survival of the ecosystem: if one species does not survive, another will be there to perform a similar function. The agroecological techniques are not limited to the maintenance of field biodiversity but also include animal integration, soil and water management etc. (see Figure 2) (Altieri et al. 2015).

Screen Shot 2018-04-20 at 11.43.31.png

Figure 2: How can agroecology cope with extreme climatic events (Altieri et al. 2015)

  1. Reducing greenhouse gas (GHG) emissions

In addition to offering resiliency to fields, agroecological practices offer the potential to decrease the GHG emission from the agricultural sector. The most obvious way is by not using pesticides, herbicides and fertilizers. The emission associated with such chemicals mainly comes from their manufacture and will widely vary depending on the type of crop and the associated need per field. Although the net GHG emission from fertilizers varies with the farm location, the total GHG emission from fertilizers is quite significant. For example, in North America it accounts for as much as 33% of the total GHG emissions (Snyder et al. 2009).

Another way in which agroecology can reduce GHG emission is by practicing low or zero tillage, which reduces soil disturbances and thus maintains soil organic carbon in the soil pool (Pretty et al. 2006, Snyder et al. 2009). The most fruitful option in terms of GHG reduction is the zero-tillage practice (Pretty et al. 2006). The importance of these practices have been debated, and the consensus seems to be that they only have the potential to significantly reduce GHG in the long run, after more than 10 years of use (Six et al. 2004). Thus, it is important to start now!

In France

In France, the Ecophyto II project has had some difficulties: between 2008 and 2014, pesticide use was increasing across the country. After this period, however, the project has shown that it is possible to have the same yield with fewer pesticides. Between 2010 and 2015, the DEPHY farms have used 18% fewer pesticides on average. Although this greatly varies between the sectors (e.g. fruits, cereals, flowers), this is encouraging for other farmers that might want to follow the same path. Across the country, a decrease of 2.7% of the use of pesticides was observed in 2015, illustrating the large impact of the project. At the moment, it is unfortunately not possible to find data on the reduction of GHG achieved by the project.

In order to boost the pesticide reduction, the government has created a certification of pesticide economy (certifict d’économie de produits phytosanitaires (CEPP)). This project is based on the white certificate concept, which entails that certificates are handed out that confirm a certain level of reduction of energy consumption has been attained. The CEPP promotes the reduction of pesticides across the country.  And why not also across Europe in the long run?

Conclusion

The agroecological project in France is relying on innovative farmers that are not afraid of risk. Ecophyto II could transform agroecology from a pioneering project in Europe to a conventional way of producing food. Because France is the largest agricultural power in the European Union, the project has a large potential to attract other farmers to follow the same path. At the moment, agroecology is being developed around Europe, as the existence of the international NGO Agroecology Europe demonstrates. This NGO aims to “analyse, design, develop and promote the transition towards agroecology-based farming and food systems”. In short, there is hope for a healthier and more climate-resilient agriculture across the world…

 

References

Altieri M, Nicholls C, Henao A, Lana M. 2015. Agroecology and the design of climate change resilient farming systems. Agronomy for Sustainable Development 35(3). Doi: 10.1007/s13593-015-0285-2

IPES-Food. 2016. From uniformity to diversity: a paradigm shift from industrial agriculture to diversified agroecological systems – International Panel of Experts on Sustainable Food systems.

Pretty J, Noble AD, Bossio D, Dixon J, Hine RE, Penning de Vries FWT, Morison JIL. 2006. Resource-Conserving Agriculture Increases Yields in Developing Countries. Environ. Sci.Technol. 40(4):1114–1119. Doi: 10.1021/es051670d

Six J, Ogle SM, Breidt FJ, Conant RT, Mosier AR, Paustian K. 2004. The potential to mitigate global warming with no-tillage management is only realized when practised in the long term. Global Change Biology 10(2):155–160. Doi: 10.1111/j.1529-8817.2003.00730.x

Snyder C, Bruulsema T, Jensen T, Fixen P. 2009. Review of greenhouse gas emissions from crop production systems and fertilizer management effects. Agriculture, Ecosystems & Environment 133(3):247–266. Doi: https://doi.org/10.1016/j.agee.2009.04.021.

Wezel A, Bellon S, Doré T, Francis C, Vallod D, David C. 2009. Agroecology as a science, a movement and a practice. Sustainable Agriculture 2:27–43. Doi: 10.1007/978-94-007-0394-0_3.