Influence of climate change on Organism Abundance in the Kiruna Region, Northern Sweden: Insights from-long term high-quality DNA sequencing

Abstract: This study investigates if the area around Kiruna, Northern Sweden has experienced large shifts in weather conditions and whether these have affected organism abundances. With a significant increase in global temperature and an increase in average temperature of 1.9 °C in Sweden during the last 130 years, it is crucial to understand the effect of climate change on organisms. The Swedish Defense Research Agency deployed an air filter station to monitor radioactive fallout. The archived filters allowed for the creation of a high-resolution time series of organism composition ranging from 1974 to 2008, based on DNA sequencing. The organisms were clustered into 17 distinct clusters based on their similarities in time series patterns.  This study found that Cluster 2 (plant pathogenic bacteria), Cluster 3 (wetland microorganisms) and Cluster 5 (planktonic bacteria) exhibited changepoint correlations with relevant climate variables. Plotting the 3 clusters and their relevant climate variables revealed that sea surface temperatures have a positive influence on the abundance of both Cluster 2 and 5. Frost change days negatively influenced Cluster 2. Dry spells positively influenced Cluster3 and 5. Additionally, the results suggest that air pressure and water deficiency in soil are predictors for Cluster 5. Overall, these findings provide insights into how climate change affects different organisms and can help inform future management decisions for these ecosystems.