Valuing Biodiversity in Life Cycle Impact Assessment

Climate and biodiversity impacts of low-density polyethylene production from CO2 and electricity in comparison to bio-based polyethylene

Plastics are essential materials for modern societies, but their production contributes to significant environmental issues. Power-to-X processes could produce plastics from captured CO₂ and hydrogen with renewable electricity, but these technologies may also face challenges from environmental perspective. This paper focuses on environmental sustainability assessment of CO₂-based low-density polyethylene (LDPE) compared to bio-based LDPE. Life cycle assessment has been applied to study climate impacts and land use related biodiversity impacts of different plastic production scenarios. According to the climate impact results, the carbon footprint of the produced plastic can be negative if the energy used is from wind, solar, or bioenergy and the carbon captured within the plastic is considered. In terms of biodiversity, land-use related biodiversity impacts seem to be lower from CO₂-based polyethylene compared to sugarcane-based polyethylene. Forest biomass use for heat production in CO₂-based polyethylene poses a risk to significantly increase biodiversity impacts. Taken together, these results suggest that CO₂-based LDPE produced with renewable electricity could reduce biodiversity impacts over 96 % while carbon footprint seems to be 6.5 % higher when compared to sugarcane-based polyethylene.

Life Cycle Assessment on Agricultural Production: A Mini Review on Methodology, Application, and Challenges

Agricultural Life Cycle Assessment (LCA) is an effective tool for the quantitative evaluation and analysis of agricultural materials production and operation activities in various stages of the agricultural system. Based on the concept of life cycle, it comprehensively summarizes the impact of agriculture on the environment, which is an effective tool to promote the sustainability and green development of agriculture. In recent years, agricultural LCA has been widely used in the agroecosystem for resource and environmental impacts analysis. However, some challenges still exist in agricultural LCA, i.e., the environmental impact assessment index system needs to be improved; its application in different production mode is limited; and combination research with other models needs more attention. This paper discusses the above-mentioned challenges and recommends research priorities for both scientific development and improvements in practical implementation. In summary, further research is needed to construct a regional heterogeneity database and develop innovated methodologies to develop more meaningful functional units for agricultural products to complement LCA by other models. These efforts will make agricultural LCA more robust and effective in environmental impacts assessment to support decision making from individual farm to regional or (inter)national for the sustainable future of agriculture.

A Conceptual Landscape-Level Approach to Assess the Impacts of Forestry on Biodiversity

In this study, we propose a conceptual approach to assessing biodiversity impacts in the life-cycle assessments (LCAs) of forest wood production with a focus on Nordic managed forests at the landscape level. As a basis for our methodology, we suggest assessing the proportion of the total land area of productive forest under the control of a forest owner that fulfils certain criteria that can be regarded as having a positive impact on the development of forest biodiversity. A similar assessment of the forest management performed on the surrounding land is used to define a site-specific reference situation. In the context of an attributional LCA, the suggested method for the specification of business-as-usual (BAU) or environmental quality objectives (EQO) baselines encourages forest owners to choose forest management options that increase the proportion of productive forest land with properties that are more favorable to biodiversity over time. We illustrate the BAU baseline approach with two examples in Sweden to calculate the biodiversity impact from wood production for individual forest owners using four biodiversity indicators from the Swedish national Environmental Quality Objectives (EQOS)—‘Living Forests’. The approach defined in this study is at this stage only applicable to forestry assessments. Using a BAU baseline approach similar to that used for international climate reporting is a simple but novel approach that makes use of consensuses that have already been drawn and approaches that have already been established.