Dark Matter Enhances Interactions within Both Microbes and Dissolved Organic Matter under Global Change

• Main Authors: Ang Hu (6533882), Fanfan Meng (8174745), Andrew J. Tanentzap (10227764), Kyoung-Soon Jang (1565791), Jianjun Wang (67330)
• Format: Other Non-Article Part of Journal/Newspaper
• Language: unknown
• Published: 1753
• Subjects: Medicine; Microbiology; Cell Biology; Genetics; Molecular Biology; Biotechnology; Evolutionary Biology; Ecology; Cancer; Inorganic Chemistry; Computational Biology; Environmental Sciences not elsewhere classified; Biological Sciences not elsewhere classified; occurrence network patterns; dissolved organic matter; without dark matter; dark matter hinders; changing biogeochemical interactions; chemical dark matter; subarctic climate zones; examine sediment bacteria; uncharacterized microbial taxa; dark matter; climate zones; chemical metabolites; biogeochemical cycles; − 15; strongly correlated; nutrient enrichment; microbial ecology; increasing temperatures; global change; findings highlight; earth ’; complete understanding; comparing co; bacterial taxa; 8 %; Norway; Subarctic
• Online Access: https://doi.org/10.1021/acs.est.2c05052.s001

There are vast but uncharacterized microbial taxa and chemical metabolites (that is, dark matter) across the Earth’s ecosystems. A lack of knowledge about dark matter hinders a complete understanding of microbial ecology and biogeochemical cycles. Here, we examine sediment bacteria and dissolved organic matter (DOM) in 300 microcosms along experimental global change gradients in subtropical and subarctic climate zones of China and Norway, respectively. We develop an indicator to quantify the importance of dark matter by comparing co-occurrence network patterns with and without dark matter in bacterial or DOM assemblages. In both climate zones, dark matter constitutes approximately 30–56% of bacterial taxa and DOM metabolites and changes connectivity within bacterial and DOM assemblages by between −15.5 and +61.8%. Dark matter is generally more important for changing network connectivity within DOM assemblages than those of microbes, especially in the subtropical zone. However, the importance of dark matter along global change gradients is strongly correlated between bacteria and DOM and consistently increased toward higher primary productivity because of increasing temperatures and nutrient enrichment. Our findings highlight the importance of microbial and chemical dark matter for changing biogeochemical interactions under global change.