Since 1970, there has been a 68% global decline of mammals, birds, fish, reptiles, and amphibians (WWF, 2020). Because of this major decrease in biodiversity, research on how human activities impact biodiversity has gained increased importance. One popular method is the life cycle assessment (LCA) of products. But how can we assess the impact on biodiversity in such an LCA?
Your impact on biodiversity
Awareness on sustainable lifestyle is growing and consumers are more and more interested in making ‘the right choice’. However, how do you decide what, for example, type of clothing is less harmful for biodiversity than the other?
Since the consumer is asking this question, companies are too. How can they decide what is the most sustainable way to produce their product? Could they use an alternative resource, or does a change in the production process or shipping result in a more sustainable product?
Luckily, there are already calculation methods that can provide useful insights into these questions. Life cycle assessment (LCA) is a method that provides information and allows for the evaluation of environmental impacts throughout a product’s life cycle.
An LCA consists of four steps:
- Define the goal and scope of an assessment
- Collect the correct data
- Calculate the environmental impacts
- Interpret the results and draw conclusions
It creates a complete product assessment, from the very first to the very last life stage of a product. Based on the results and the conclusions, managers and investors are informed to make better business decisions.
Biodiversity in life cycle assessments
In the last two decades, many great improvements are made to LCA methodology. However, assessing biodiversity remains a challenge. A difficulty for LCA methodology, in general, is a lack of specific data. Therefore, all LCA methods have to make some concessions and assumptions in order to represent the environment as realistic as possible.
In the third step of an LCA, the Life Cycle Impact Assessment (LCIA), the impact on biodiversity can be quantified. This step allows for a translation of the inventory flows of a given life cycle into a limited number of environmental impact scores. Some LCA methodologies include the translation to biodiversity in this step.
The few impact assessment methods that include biodiversity, all have one or more of the following gaps or weaknesses: species diversity, spatial resolution of impact assessment models versus spatial resolution of inventory data, impacts of only three drivers (mostly land use) for biodiversity loss, and the trade-off between biology and LCA (Winter et al., 2018).
The attached research includes five methods: ReCiPe2016, IMPACT World+, LC-IMPACT, PBF, and BIA+. The methods are assessed on how they address the four main knowledge gaps for assessing biodiversity. The five methods are introduced individually, their general framework and how they include biodiversity quantification is explained. Afterwards is shown how each knowledge gap is addressed by the methods.
Expressing biodiversity in LCA results
As with all LCIA methods, ReCiPe2016, IMPACT World+, LC-IMPACT, PBF, and BIA+ provide a simplified representation of the environmental mechanisms. The combination of modelling decisions and the limited knowledge of environmental sciences are recurring challenges for LCA methodology. Nevertheless, quantification of biodiversity in LCA methodology has shown promising developments over the last few years. An overview of the developments in the assessed methods can be seen in Table 1.
Species richness remains the most usable representation of biodiversity. However, effort is made to present biodiversity as an abstract concept to include genetic and ecosystem diversity. As more data becomes available, the spatial resolution of LCA assessments can increase.
On top of this, inclusion of all five drivers for biodiversity loss is becoming a possibility. Lastly, most methods present a way for weighted choices regarding the trade-off between biology research and LCA frameworks.
Besides fine-tuning the already available assessment methods, it would be valuable to include ecosystem services in LCA frameworks in the future. On top of this, current LCA methodology focuses strongly on biodiversity loss. Future research is required to also allow the implementation of positive impacts on it in LCA frameworks.
This assessment shows improvements have been introduced for biodiversity quantification in LCA methodology. Methods published in the last few years address the knowledge gaps for biodiversity quantification, although some gaps are better covered than others. Altogether, LCA results should always be interpreted with care and with acknowledgement for the modelling choices, hypotheses, and limitations.
Sources and links
[1] Asselin, A., Rabaud, S., Catalan, C., Leveque, B., L’Haridon, J., Martz, P., & Neveux, G. (2020). Product Biodiversity Footprint – A novel approach to compare the impact of products on biodiversity combining Life Cycle Assessment and Ecology. Journal of Cleaner Production, 248, 119262.
[2] Bulle, C., Margni, M., Patouillard, L., Boulay, A. M., Bourgault, G., De Bruille, V. & Jolliet, O. (2019). IMPACT World+: a globally regionalized life cycle impact assessment method. The International Journal of Life Cycle Assessment, 24(9), 1653-1674.
[3] Huijbregts, M. A., Steinmann, Z. J., Elshout, P. M., Stam, G., Verones, F., Vieira, M. D. M., & Van Zelm, R. (2017). ReCiPe2016: a harmonised life cycle impact assessment method at midpoint and endpoint level. The International Journal of Life Cycle Assessment, 22(2), 138-147.
[4] Verones, F., Hellweg, S., Azevedo, L. B., Chaudhary, A., Cosme, N., Fantke, P., & Huijbregts, M. A. J. (2016). LC-Impact Version 0.5: a spatially differentiated life cycle impact assessment approach. Advance Access published.
[5] Winter, L., Pflugmacher, S., Berger, M., & Finkbeiner, M. (2018). Biodiversity impact assessment (BIA+) – methodological framework for screening biodiversity. Integrated environmental assessment and management, 14(2), 282-297.
[6] WWF – World Wide Fund For Nature (2020). Living Planet Report 2020 – Bending the curve of biodiversity loss. Almond, R.E.A., Grooten M. and Petersen, T. (Eds). WWF, Gland, Switzerland.
