Speaker
Description
Keywords: organic farming, GHG emissions, climate change mitigation, Brazil
1. Introduction
Organic agri-food systems are an alternative to the sustainability challenges of today’s conventional systems. However, knowledge of their effectiveness in reducing greenhouse gas (GHG) emissions is limited and provides heterogeneous results (Boschiero et al., 2023). This is particularly important in the Brazilian context, where the agricultural sector and land-use change contribute to a large share of GHG emissions. In addition, Brazil’s government has actively encouraged the conversion to organic farming with its National Policy for Agroecology and Organic Production in 2012. It was a federal policy that supported the sustainable development of rural communities through the adoption of agroecological and organic farming techniques. Yet, whether this policy facilitated a trend towards lower agricultural GHG emissions has not been investigated.
In this study, we explore whether Brazil’s incentives for organic farming align with its emission reduction targets. This is important because, despite the acknowledged environ- mental benefits of organic farming, a debate persists regarding its effectiveness in mitigating GHG emissions. For example, there is a consensus on its benefits for soil health, lower dependence on non-renewable resources, and diminished ecological footprint (Chamorro et al., 2016; Lori et al., 2017; Gamage et al., 2023). On the other hand, studies have reported fewer emissions per unit of land (Tuomisto et al., 2012), higher emissions per yield (Skinner et al., 2014), diminished N2O emissions (Skinner et al., 2019), or no significant difference between organic and conventional systems (Clark and Tilman, 2017). Addi- tionally, organic farming’s lower yields may require larger production areas, increasing emissions related to land-use change (de Ponti et al., 2012; Meier et al., 2015). Therefore, our study aims to assess the potential of organic farming to contribute to a low-carbon future and climate change mitigation.
2. Data and Methods
We combine two data sources. Annual farming emissions from Brazilian municipalities between 2000 and 2019 (SEEG, 2023) and Agricultural Census data on organic agriculture for 2006 and 2017. This creates a comprehensive data set with information from 5,537 municipalities.
With this data, we perform an econometric estimation of the effect of expanding organic farming on GHG emissions. To address potential endogeneity concerns, we integrate propensity score matching (PSM) and instrumental variable (IV) techniques. This com- bined approach allows us to account for the spatial distribution of organic farms, thereby reducing omitted variables bias. We use a targeted credit program as an exogenous source of variation to create our instrument. The program is called Pronaf Agroecologia and is part of an effort to enhance agroecological and organic farming by providing financial assistance to farmers. More specifically, the instrument considers whether a municipality is within a state that has received this credit. Equation 1 outlines the model specification.
\begin{eqnarray}\label{eq:main1}
Y_{i} = \beta\,{0} + \beta\,{1}\hat{org}{i} + \gamma \mathbf{X}{i}+ \varepsilon_{it}
\end{eqnarray}
The dependent variable (Y_i) is the absolute variation in emissions per hectare between 2017 and 2006, and org is the difference between the percent of organic farms in 2017 compared to 2006. Xi is a vector for observable municipality characteristics, including the farming sector size, different farming systems, and yields.
3. Preliminary Results
Findings from a preliminary analysis indicate that organic farming expansion is associated with lower emissions per hectare. This suggests that municipalities experiencing an increase in organic production had a decrease in total emissions per unit of land. This result underscores the complexity of the relationship between organic farming and emissions, highlighting the importance of context-specific considerations in designing effective environmental policies.
References
Boschiero, M., De Laurentiis, V., Caldeira, C., and Sala, S. (2023). Comparison of organic and conventional cropping systems: A systematic review of life cycle assessment studies. Environmental Impact Assessment Review, 102:107187.
Chamorro, L., Masalles, R., and Sans, F. (2016). Arable weed decline in northeast Spain: Does organic farming recover functional biodiversity? Agriculture, Ecosystems amp; Environment, 223:1–9.
Clark, M. and Tilman, D. (2017). Comparative analysis of environmental impacts of agricultural production systems, agricultural input efficiency, and food choice. Environmental Research Letters, 12(6):064016.
de Ponti, T., Rijk, B., and van Ittersum, M. K. (2012). The crop yield gap between organic and conventional agriculture. Agricultural Systems, 108:1–9.
Gamage, A., Gangahagedara, R., Gamage, J., Jayasinghe, N., Kodikara, N., Suraweera, P., and Merah, O. (2023). Role of organic farming for achieving sustainability in agriculture. Farming System, 1(1):100005.
Lori, M., Symnaczik, S., Mäder, P., De Deyn, G., and Gattinger, A. (2017). Organic farming enhances soil microbial abundance and activity—a meta-analysis and meta-regression. PLOS ONE, 12(7):e0180442.
Meier, M. S., Stoessel, F., Jungbluth, N., Juraske, R., Schader, C., and Stolze, M. (2015). Environmental impacts of organic and conventional agricultural products – are the differences captured by life cycle assessment? Journal of Environmental Management, 149:193–208.
SEEG (2023). SEEG Brasil: O Sistema de Estimativas de Emissões e Remoções de Gases de Efeito Estufa. https://seeg.eco.br/. [Accessed 13-11-2023].
Skinner, C., Gattinger, A., Krauss, M., Krause, H.-M., Mayer, J., van der Heijden, M.
Skinner, C., Gattinger, A., Krauss, M. et al. The impact of long-term organic farming on soil-derived greenhouse gas emissions. Sci Rep 9, 1702 (2019). https://doi.org/10.1038/s41598-018-38207-w
Skinner, C., Gattinger, A., Muller, A., Mäder, P., Fliebach, A., Stolze, M., Ruser, R., and Niggli, U. (2014). Greenhouse gas fluxes from agricultural soils under organic and non-organic management — a global meta-analysis. Science of The Total Environment, 468–469:553–563.
Tuomisto, H., Hodge, I., Riordan, P., and Macdonald, D. (2012). Does organic farming reduce environmental impacts? – a meta-analysis of European Research. Journal of Environmental Management, 112:309–320.
