Validating Farmland Biodiversity Life Cycle Assessment at the Landscape Scale

Lifecycle assessment (LCA) is increasingly used to evaluatethe impacts of agricultural production on the environment. This studyvalidated an LCA tool in predicting bird/butterfly richness at thefield/landscape scale and tested if the spatial context can improvethe prediction. Life cycle assessment (LCA) aims at providing standardizedevaluationsof processes involving resource use, human health, and environmentalconsequences. Currently, spatial dependencies are most often neglected,though they are essential for impact categories like biodiversity.The Swiss Agricultural Life Cycle Assessment for Biodiversity(SALCA-BD) evaluates the impact of agricultural field managementon 11 indicator species groups. We tested if its performance can beimproved by accounting for the spatial context of the individual fields.We used high-resolution bird/butterfly point observations in two agriculturalregions in Switzerland and built linear mixed models to compare SALCA-BDscores to the observed species richness at the field/landscape scale.We calculated a set of landscape metrics, tested their relationshipwith the landscape-model prediction errors, and then added all significantmetrics as additional predictors to the landscape models. Our resultsshow that field-scale SALCA-BD scores were significantly related tothe observed field-scale richness for both indicator groups. However,the performance decreased when aggregated to the landscape scale,with high variability between regions. Adding specific landscape metricsimproved the landscape model for birds but not for butterflies. Integratingthe spatial context to LCA biodiversity assessments could providemoderate benefits, while its usefulness depends on the conditionsof the respective assessment.

Automated summary

This study validated an LCA tool in predicting bird/butterfly richness at the field/landscape scale and tested the improvement of prediction by considering the spatial context. The results showed that adding specific landscape metrics improved the landscape model for birds but not for butterflies.