A new perspective on how organic matter drives Earth’s carbon cycle is taking shape through the concept of “functional chemogeography,” as introduced by our recent paper in Global Change Biology. We propose this innovative framework to explain how the chemical traits of organic molecules—rather than just their identities—govern their transformation, persistence, and ecological roles across space and time. By emphasizing molecular traits that respond to environmental change, the framework connects microscopic chemical diversity to macroscopic biogeochemical processes, offering a more predictive understanding of how ecosystems regulate carbon storage and climate feedbacks.
In contrast to traditional approaches that focus on identifying and quantifying molecular compositions, functional chemogeography integrates both intrinsic traits (those inherent to molecular structures) and extrinsic traits (those reflecting biochemical transformations and environmental interactions). The study highlights how these extrinsic traits, when summarized at the community level using functional diversity metrics, can explain ecological and biogeochemical patterns more effectively than composition alone. A case study of dissolved organic matter (DOM) in Chinese lakes illustrates how this framework can uncover the mechanisms behind carbon cycling and its sensitivity to environmental shifts.
By merging advances in ultrahigh-resolution mass spectrometry with trait-based ecology, this framework marks a turning point in the study of environmental organic chemistry. Functional chemogeography provides a pathway to predict how global organic carbon will behave under future climate scenarios—bridging the molecular complexity of natural organic matter with the broader goals of ecosystem modeling and climate mitigation.
Here comes the abstract:
Organisms in ecosystems continuously release a myriad of organic matter molecules that undergo microbial and abiotic transformation, processes that critically influence carbon storage and climate feedbacks. Yet, a systematic understanding of what determines the transformation and persistence of organic matter across spatiotemporal scales remains elusive. We propose an emerging framework, termed “functional chemogeography,” to understand transformation and persistence of organic matter based on the chemical traits of molecules. This framework extends beyond a sole focus on intrinsic traits, which remain relatively constant across spatiotemporal scales, to emphasize extrinsic traits such as biochemical transformations and environmental responses, which vary spatiotemporally and are shaped by both intrinsic traits and the environment. When upscaled to the assemblage level using functional diversity indices, these extrinsic traits reveal a significant, and in some cases superior, capacity than intrinsic traits to explain biogeochemical processes, as demonstrated through a case study of dissolved organic matter in China's lakes. By integrating trait-based perspectives into predictive models, this framework helps bridge chemical complexity with ecosystem biogeochemistry, thereby advancing our ability to predict the fate of global organic carbon under environmental change.
Hot to cite:
Hu A, et al. The Emergence and Promise of Functional Chemogeography of Organic Matter. Global Change Biol., 2025, 31(8):e70435. https://onlinelibrary.wiley.com/doi/10.1111/gcb.70435 [Full Text]
