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Abstract

Data set that was used to determine the frequency each of 4 key words (public engagement, education, outreach, or science communication) in the title or abstract of published papers in Freshwater Science (formerly the Journal of the North American Benthological Society) and oral presentations (talks) at the annual Society for Freshwater Science meetings from 1997 to 2019. Does not include any data on talks for 2013-2014 because they were not published during those years.

Methods

The dataset was collected by reviewing abstracts in the journal Freshwater Science (formerly the Journal of North American Benthological Society [JNABS]) from 1997 to 2019 as well as searching abstracts from oral presentations at the SFS Annual Meeting (available online for 1997–2012 and 2015–2019 at https://sfsannualmeeting.org/SearchAll.cfm) for key words (public engagement, science communication, education, outreach) related to PES. The dataset was processed by inputting the data collected from our search (i.e., year, type of work, keyword, and number of times the keyword appeared in that type of work during the specified year) into a .csv file using Microsoft Excel. R was used (https://www.r-project.org/) and its accompanying package ggplot2 (https://ggplot2.tidyverse.org/) to plot the data.

Anthropogenic increases in nitrogen (N) and phosphorus (P) concentrations can strongly influence the structure and function of ecosystems. Even though lotic ecosystems receive cumulative inputs of nutrients applied to and deposited on land, no comprehensive assessment has quantified nutrient‐enrichment effects within streams and rivers. We conducted a meta‐analysis of published studies that experimentally increased concentrations of N and/or P in streams and rivers to examine how enrichment alters ecosystem structure (state: primary producer and consumer biomass and abundance) and function (rate: primary production, leaf breakdown rates, metabolism) at multiple trophic levels (primary producer, microbial heterotroph, primary and secondary consumers, and integrated ecosystem). Our synthesis included 184 studies, 885 experiments, and 3497 biotic responses to nutrient enrichment. We documented widespread increases in organismal biomass and abundance (mean response = +48%) and rates of ecosystem processes (+54%) to enrichment across multiple trophic levels, with no large differences in responses among trophic levels or between autotrophic or heterotrophic food‐web pathways. Responses to nutrient enrichment varied with the nutrient added (N, P, or both) depending on rate versus state variable and experiment type, and were greater in flume and whole‐stream experiments than in experiments using nutrient‐diffusing substrata. Generally, nutrient‐enrichment effects also increased with watermore »temperature and light, and decreased under elevated ambient concentrations of inorganic N and/or P. Overall, increased concentrations of N and/or P altered multiple food‐web pathways and trophic levels in lotic ecosystems. Our results indicate that preservation or restoration of biodiversity and ecosystem functions of streams and rivers requires management of nutrient inputs and consideration of multiple trophic pathways.« less

The reactivity of metals associated with ash from wood collected from the Valles Caldera National Preserve, Jemez Mountains, New Mexico, was assessed through a series of laboratory experiments. Microscopy, spectroscopy, diffraction, and aqueous chemistry measurements were integrated to determine the chemical composition of wood ash and its effect on water chemistry. Climate change has caused dramatic impacts and stresses that have resulted in large-scale increases in wildfire activity in semi-arid areas of the world. Metals and other constituents associated with wildfire ash can be transported by storm event runoff and negatively affect the water quality in streams and rivers. Differences among ash from six tree species based on total concentrations of metals such as Ca, Al, Mg, Fe, and Mn were identified using non-metric multidimensional analysis. Metal-bearing carbonate and oxide phases were quantified by X-ray diffraction analyses and X-ray spectroscopy analyses. These metal-bearing carbonate phases were readily dissolved in the first 30 minutes of reaction with 18 MΩ water and 10 mM HCO 3 − in laboratory batch experiments which resulted in the release of metals and carbonates in the ash, causing water alkalinity to increase. However, metal concentrations decreased over the course of the experiment, suggesting that metals re-adsorbmore »to ash. Our results suggest that the dissolution of metal-bearing carbonate and oxide phases in ash and metal re-adsorption to ash are relevant processes affecting water chemistry after wildfire events. These results have important implications to better understand the impact of wildfire events on water quality.« less