@article {robison_dominance_2022,
	title = {Dominance of {Diffusive} {Methane} {Emissions} {From} {Lowland} {Headwater} {Streams} {Promotes} {Oxidation} and {Isotopic} {Enrichment}},
	journal = {Frontiers in Environmental Science},
	volume = {9},
	year = {2022},
	pages = {791305},
	abstract = {Inland waters are the largest natural source of methane (CH 4 ) to the atmosphere, yet the contribution from small streams to this flux is not clearly defined. To fully understand CH 4 emissions from streams and rivers, we must consider the relative importance of CH 4 emission pathways, the prominence of microbially-mediated production and oxidation of CH 4 , and the isotopic signature of emitted CH 4 . Here, we construct a complete CH 4 emission budgets for four lowland headwater streams by quantifying diffusive CH 4 emissions and comparing them to previously published rates of ebullitive emissions. We also examine the isotopic composition of CH 4 along with the sediment microbial community to investigate production and oxidation across the streams. We find that all four streams are supersaturated with respect to CH 4 with diffusive emissions accounting for approximately 78{\textendash}100\% of total CH 4 emissions. Isotopic and microbial data suggest CH 4 oxidation is prevalent across the streams, depleting approximately half of the dissolved CH 4 pool before emission. We propose a conceptual model of CH 4 production, oxidation, and emission from small streams, where the dominance of diffusive emissions is greater compared to other aquatic ecosystems, and the impact of CH 4 oxidation is observable in the emitted isotopic values. As a result, we suggest the CH 4 emitted from small streams is isotopically heavy compared to lentic ecosystems. Our results further demonstrate streams are important components of the global CH 4 cycle yet may be characterized by a unique pattern of cycling and emission that differentiate them from other aquatic ecosystems.},
	issn = {2296-665X},
	doi = {10.3389/fenvs.2021.791305},
	url = {https://www.frontiersin.org/articles/10.3389/fenvs.2021.791305/full},
	author = {Robison, Andrew L. and Wollheim, Wilfred M. and Perryman, Clarice R. and Cotter, Annie R. and Mackay, Jessica E. and Varner, Ruth K. and Clarizia, Paige and Ernakovich, Jessica G.}
}
@article {wollheim_superlinear_2022,
	title = {Superlinear scaling of riverine biogeochemical function with watershed size},
	journal = {Nature Communications},
	volume = {13},
	number = {1},
	year = {2022},
	pages = {1230},
	abstract = {River networks regulate carbon and nutrient exchange between continents, atmosphere, and oceans. However, contributions of riverine processing are poorly constrained at continental scales. Scaling relationships of cumulative biogeochemical function with watershed size (allometric scaling) provide an approach for quantifying the contributions of fluvial networks in the Earth system. Here we show that allometric scaling of cumulative riverine function with watershed area ranges from linear to superlinear, with scaling exponents constrained by network shape, hydrological conditions, and biogeochemical process rates. Allometric scaling is superlinear for processes that are largely independent of substrate concentration (e.g., gross primary production) due to superlinear scaling of river network surface area with watershed area. Allometric scaling for typically substrate-limited processes (e.g., denitrification) is linear in river networks with high biogeochemical activity or low river discharge but becomes increasingly superlinear under lower biogeochemical activity or high discharge, conditions that are widely prevalent in river networks. The frequent occurrence of superlinear scaling indicates that biogeochemical activity in large rivers contributes disproportionately to the function of river networks in the Earth system.},
	issn = {2041-1723},
	doi = {10.1038/s41467-022-28630-z},
	url = {https://doi.org/10.1038/s41467-022-28630-z},
	author = {Wollheim, Wilfred M. and Harms, Tamara K. and Robison, Andrew L. and Koenig, Lauren E. and Helton, Ashley M. and Song, Chao and Bowden, William B. and Finlay, Jacques C.}
}
@article {robison_spatial_2021,
	title = {Spatial and temporal heterogeneity of methane ebullition in lowland headwater streams and the impact on sampling design},
	journal = {Limnology and Oceanography},
	volume = {66},
	number = {12},
	year = {2021},
	month = {dec},
	pages = {4063{\textendash}4076},
	issn = {0024-3590, 1939-5590},
	doi = {10.1002/lno.11943},
	url = {https://onlinelibrary.wiley.com/doi/10.1002/lno.11943},
	author = {Robison, Andrew L. and Wollheim, Wilfred M. and Turek, Bonnie and Bova, Cynthia and Snay, Carter and Varner, Ruth K.}
}
