Integrating terrestrial and aquatic ecosystems to constrain estimates of land-atmosphere carbon exchange.

In this Perspective, we put forward an integrative framework to improve estimates of land-atmosphere carbon exchange based on the accumulation of carbon in the landscape as constrained by its lateral export through rivers. The framework uses the watershed as the fundamental spatial unit and integrates all terrestrial and aquatic ecosystems as well as their hydrologic carbon exchanges. Application of the framework should help bridge the existing gap between land and atmosphere-based approaches and offers a platform to increase communication and synergy among the terrestrial, aquatic, and atmospheric research communities that is paramount to advance landscape carbon budget assessments.

Large-scale sampling of the freshwater microbiome suggests pollution-driven ecosystem changes.

Freshwater microbes play a crucial role in the global carbon cycle. Anthropogenic stressors that lead to changes in these microbial communities are likely to have profound consequences for freshwater ecosystems. Using field data from the coordinated sampling of 617 lakes, ponds, rivers, and streams by citizen scientists, we observed linkages between microbial community composition, light and chemical pollution, and greenhouse gas concentration.

Modeling the spatial and temporal variability in surface water CO and CH concentrations in a newly created complex of boreal hydroelectric reservoirs.

Hydroelectric reservoirs emit carbon dioxide (CO) and methane (CH) to the atmosphere, yet there is still much uncertainty concerning the magnitude and drivers of these greenhouse gas (GHG) emissions. This uncertainty is particularly large over the initial years after flooding and in complex, cascade reservoir systems where studies are rare. We assessed the spatial and temporal patterns of CO and CH concentrations in the newly created La Romaine complex, which is composed of three consecutive reservoirs (RO1, RO2, RO3) along the La Romaine River.

Spatial and temporal variability of methane emissions from cascading reservoirs in the Upper Mekong River.

Reservoirs are an important source of atmospheric methane (CH), a potent greenhouse gas. The Mekong, one of the largest Asian rivers, has been heavily dammed and can be a potential hotspot for CH emissions. While low diffusive CH flux was previously reported from cascading reservoirs in the Upper Mekong, the contribution of ebullition (bubbling) remained unexplored.

Collaborative Projects: Unleashing Early Career Scientists' Power.

Collaborative research projects exclusively targeted to early career researchers (ECRs) have been initiated in Europe. So far, the first two collaborative projects have united more than 80 ECRs. We describe the structure and benefits of such initiatives for the ECRs and highlight the positive influence on the whole scientific community.