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Rising temperatures and globalization are enabling widespread biotic invasions today, particularly in marine environments. While the long-term consequences of invasion are poorly understood, the fossil record can be used to assess the impacts of past invasions on ecosystem structure and functioning on evolutionary timescales. During the Late Ordovician (Katian), ~445.25 million years ago, deglaciation and subsequent rising sea level connected formerly isolated shallow epicontinental seas, facilitating the invasion of over 75 genera through larval dispersal in several pulses known as the Richmondian Invasion. Here we examine 1,139 species from these benthic marine communities of the Cincinnati Arch (USA) to quantify the effects of invasive species on functional diversity, which has been shown to influence ecosystem dynamics, stability, productivity, and functioning. Changes in functional diversity were quantified across six 3^rd-order stratigraphic sequences to assess the impacts of invasion using functional traits readily identifiable in fossil taxa: tiering above the substrate, feeding mode, motility/attachment, structural robustness, trophic rank, vision, and body form. We find that despite well documented changes in community composition, the arrival of invaders did not significantly add new functional entities or dramatically alter functional diversity, and invaders largely occupied pre-existing functions. While there were changes across the invasion, community structure ultimately returned to a state similar to the pre-invasion community. This suggests that despite changes in community composition across the Richmondian Invasion, ultimately the invasion did not substantially restructure functional diversity, as we observed little change in the number of functions, functional redundancy and over redundancy, vulnerability, and the distribution of species among functional entities. These findings emphasize the decoupling of changes in community composition and functional diversity, and the importance of functional diversity in assessing the potential ecological impacts of marine invasions today. 

Abstract The future of coastal marshes depends in part on their ability to migrate inland with sea level rise into coastal forests, but projections of land conversion commonly assume that migration occurs over a static terrestrial topography. Here, we assess the assumption of a static topography in a rapidly retreating coastal upland forest by measuring surface accretion, subsurface expansion or subsidence, and net elevation change across a gradient of salinity and inundation stress. We found that salt-affected forest soils were largely stable over the 5-year study period, exhibiting limited elevation change (–0.2 to 1.5 mm yr⁻¹) in most stages of forest health. This stability was achieved by relatively equal and offsetting rates of accretion and subsidence that were each greater than expected. Surface accretion rates were positively correlated with the total cover ofMorella ceriferashrubs rather thanPhragmites australis, an invasive reed that dominates retreating coastal forests in the mid-Atlantic. Subsidence was greatest in higher elevation forest areas and attributed to root zone collapse that occurred prior to ongoing tree mortality. Net elevation-change rates were highest in the marsh-forest transition zone (2.9 mm yr⁻¹), which is characterized by dead trees and fully developed marsh vegetation. Though this study measured relatively low elevation change rates in most portions of a retreating coastal forest, similarity between transition zone and adjacent salt marsh rates suggests that elevation change rates respond quickly to marsh migration and are elevated by the time of extensive tree mortality. 

Abstract Grassy ecosystems cover >25% of the world's land surface area. The abundance of herbaceous vegetation in these systems directly impacts a variety of ecological processes, including carbon sequestration, regulation of water and nutrient cycling, and support of grazing wildlife and livestock. Efforts to quantify herbaceous biomass, however, are often limited by a trade‐off between accuracy and spatial scale. Here, we describe a method for using Light Detection and Ranging (LiDAR) to estimate continuous aboveground biomass (AGB) at sub‐meter resolutions over large (10–10 000 ha) spatial scales. Across two African savanna ecosystems, we compared field‐ and LiDAR‐derived structural metrics—including measures of vegetation height and volume—with destructively harvested AGB by aligning our geospatial data with the location of harvested quadrats. Using this combination of approaches, we develop scaling equations to estimate spatially continuous herbaceous AGB over large areas. We demonstrate the utility of this method using a long‐term, large herbivore exclosure experiment as a case study and comprehensively compare common field‐ and LiDAR‐derived metrics for estimating herbaceous AGB. Our results indicate that UAV‐borne LiDAR provides comparable accuracy to standard field methods but over considerably larger areas. Nearly every measure of vegetation structure we quantified using LiDAR provided estimates of AGB that were comparable in accuracy (R² > 0.6) to the suite of common field methods we evaluated. However, marked differences between our two sites indicate that, for applications where accurate estimation of absolute biomass is a priority, site‐specific parameterization with destructive harvesting is necessary regardless of methodology. With the increasing availability of high‐resolution remote sensing data globally, our results indicate that many measures of herbaceous vegetation structure can be used to accurately compare AGB, even in the absence of complementary field data. 

This data set contains biomass and physical data across an upland forest to marsh transition. These measurements are taken at 5 sites around the Chesapeake and Delaware Bays. Data is collected at up to 5 ectones across the upland to marsh (High Marsh, Transition Zone, Low, Mid and High Forest). These ecotone definitions follow Smith et al. 2019, https://doi.org/10.6073/pasta/4524c22708628eb7f06d174edae89ff2). 

The Energy Grid Card Game was designed for pre-college students (grades 6-12) to be played in an informal learning environment. The game explores the technical, environmental, and economic choices and challenges of using energy resources throughout our daily lives. Undergraduates at Illinois State University designed the activity as part of the NSF-funded SUPERCHARGE project, which seeks to improve access to STEM college and career pathways while making connections to engineering and sustainability-related problems that can be addressed in their communities. 

The following activities are examples from a unit of study that focuses on harnessing, using, and controlling energy. These activities were designed for pre-college learners in grades 6-12 in informal learning settings as part of the SUPERCHARGE project] by undergraduates at Illinois State University. The goal of the project is to promote interest in college and career pathways related to engineering, sustainability, and renewable energy technologies. 

ABSTRACT Sea level rise and storm surges affect coastal forests along low‐lying shorelines. Salinization and flooding kill trees and favour the encroachment of salt‐tolerant marsh vegetation. The hydrology of this ecological transition is complex and requires a multidisciplinary approach. Sea level rise (press) and storms (pulses) act on different timescales, affecting the forest vegetation in different ways. Salinization can occur either by vertical infiltration during flooding or from the aquifer driven by tides and sea level rise. Here, we detail the ecohydrological processes acting in the critical zone of retreating coastal forests. An increase in sea level has a three‐pronged effect on flooding and salinization: It raises the maximum elevation of storm surges, shifts the freshwater‐saltwater interface inland, and elevates the water table, leading to surface flooding from below. Trees can modify their root systems and local soil hydrology to better withstand salinization. Hydrological stress from intermittent storm surges inhibits tree growth, as evidenced by tree ring analysis. Tree rings also reveal a lag between the time when tree growth significantly slows and when the tree ultimately dies. Tree dieback reduces transpiration, retaining more water in the soil and creating conditions more favourable for flooding. Sedimentation from storm waters combined to organic matter decomposition can change the landscape, affecting flooding and runoff. Our results indicate that only a multidisciplinary approach can fully capture the ecohydrology of retreating forests in a period of accelerated sea level rise.