The paper "Plumbing the Global Carbon Cycle: Integrating Inland Waters into the Terrestrial Carbon Budget" by J. J. Cole et al. explores the role of inland freshwater ecosystems in the global carbon cycle. The authors argue that these ecosystems, including lakes, rivers, and reservoirs, have been underrepresented in global carbon budgets due to their small surface area. By analyzing published estimates of gas exchange, sediment accumulation, and carbon transport, they construct a budget for the role of inland waters in the global carbon cycle. Key findings include: - Inland waters receive approximately 1.9 Pg C y⁻¹ from the terrestrial landscape, with about 0.2 Pg buried in sediments, 0.8 Pg returned to the atmosphere as gas exchange, and 0.9 Pg delivered to the oceans. - The net carbon flux in aquatic systems tends to be greater per unit area than in surrounding land, affecting regional carbon balances. - The inclusion of inland freshwater ecosystems provides valuable insights into the storage, oxidation, and transport of terrestrial carbon, potentially requiring a revision of how the modern net carbon sink on land is described. The paper also discusses the importance of small streams, wetlands, and groundwater in the carbon cycle, and highlights the need for more research to better understand these components. The authors conclude that inland waters are active components of the global carbon cycle and should be considered in global carbon budgets to improve our understanding of the biosphere's functioning.The paper "Plumbing the Global Carbon Cycle: Integrating Inland Waters into the Terrestrial Carbon Budget" by J. J. Cole et al. explores the role of inland freshwater ecosystems in the global carbon cycle. The authors argue that these ecosystems, including lakes, rivers, and reservoirs, have been underrepresented in global carbon budgets due to their small surface area. By analyzing published estimates of gas exchange, sediment accumulation, and carbon transport, they construct a budget for the role of inland waters in the global carbon cycle. Key findings include: - Inland waters receive approximately 1.9 Pg C y⁻¹ from the terrestrial landscape, with about 0.2 Pg buried in sediments, 0.8 Pg returned to the atmosphere as gas exchange, and 0.9 Pg delivered to the oceans. - The net carbon flux in aquatic systems tends to be greater per unit area than in surrounding land, affecting regional carbon balances. - The inclusion of inland freshwater ecosystems provides valuable insights into the storage, oxidation, and transport of terrestrial carbon, potentially requiring a revision of how the modern net carbon sink on land is described. The paper also discusses the importance of small streams, wetlands, and groundwater in the carbon cycle, and highlights the need for more research to better understand these components. The authors conclude that inland waters are active components of the global carbon cycle and should be considered in global carbon budgets to improve our understanding of the biosphere's functioning.