A global analysis of terrestrial plant litter dynamics in non-perennial waterways

Perennial rivers and streams make a disproportionate contribution to global carbon (C) cycling. However, the contribution of intermittent rivers and ephemeral streams (IRES), which sometimes cease to flow and can dry completely, is largely ignored although they represent over half the global river network. Substantial amounts of terrestrial plant litter (TPL) accumulate in dry riverbeds and, upon rewetting, this material can undergo rapid microbial processing. We present the results of a global research collaboration that collected and analysed TPL from 212 dry riverbeds across major environmental gradients and climate zones. We assessed litter decomposability by quantifying the litter carbon-to-nitrogen ratio and oxygen (O2) consumption in standardized assays and estimated the potential short-term CO2 emissions during rewetting events. Aridity, cover of riparian vegetation, channel width and dry-phase duration explained most variability in the quantity and decomposability of plant litter in IRES. Our estimates indicate that a single pulse of CO2 emission upon litter rewetting contributes up to 10% of the daily CO2 emission from perennial rivers and stream, particularly in temperate climates. This indicates that the contributions of IRES should be included in global C-cycling assessments

Corrosion derived lubricant infused surfaces on X65 carbon steel for improved inorganic scaling performance

Slippery Liquid Infused Porous Surfaces (SLIPS) are a relatively new and promising development in the surface engineering world. Bio-inspired with superior omniphobicity and robustness, SLIPS have enjoyed success in several scientific applications, spanning multiple industries from the marine environment to the medical field. Inorganic fouling is one such challenge SLIPS have managed to overcome by disrupting both the deposition and adhesion mechanics of scale. To date, the primary focus has been on adapting stainless steels while more prevalent pipeline materials, such as carbon steel, have been overlooked. Here a unique and simple SLIPS system has been fabricated from X65 carbon steel, with the potential for creation of a SLIPS system in situ. Utilizing the topographical features of an FeCO3 layer derived from CO2 corrosion, two SLIPS, one with perfluorinated Krytox oil and another with 1-Butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide have been tested. The SLIPS have been validated with prevailing models in SLIPS design literature and shed further insight into how this is determined experimentally. This SLIPS combination spares the use of a functionalization layer between the substrate/lubricant interface and displays enhanced anti-fouling capabilities in a calcium carbonate (CaCO3) scaling brine