Development of the Groundwater Concept Inventory to Measure Groundwater Knowledge in a General Audience.

Groundwater is a critical resource globally, and understanding groundwater processes is vital to ensure sustainable management practices. However, there are many widely held misconceptions and inaccuracies about groundwater, and we currently lack tools to measure groundwater knowledge across large populations and measure how groundwater knowledge relates to management decisions or behaviors. Here, we present a survey instrument, the Groundwater Concept Inventory (GWCI), that has been designed for general audiences to measure groundwater knowledge comparable to that in an introductory geoscience curriculum. The GWCI was developed using ∼1200 responses using an online platform, Amazon Mechanical Turks, to represent a general population. Responses were evaluated using the Rasch model that configures a relationship between person-ability and item-difficulty. We found that the study population displayed similar misconceptions about groundwater compared with previous literature, and that age and education were not strong predictors of GWCI scores. The GWCI can be used by researchers to understand links between knowledge and behavior, and also by other stakeholders to quantify misconceptions about groundwater and target resources for a more informed public.

Biosensors Show Promise as a Measure of Student Engagement in a Large Introductory Biology Course.

This study measured student engagement in real time through the use of skin biosensors, specifically galvanic skin response (GSR), in a large undergraduate lecture classroom. The study was conducted during an intervention in an introductory-level biology course (N = 420) in which one section of the course was taught with active-learning approaches and the other with traditional didactic teaching. GSR results were aligned and correlated with the Classroom Observation Protocol for Undergraduate STEM, or COPUS, and student self-reflections on their own engagement. Results showed that the active-learning section spent more time working in groups, resulting in GSR measures that trended higher and self-reported engagement, while showing indications of higher content learning gains compared with the traditional lecture section. Comparisons between COPUS scores and GSR readings indicate that engagement increased during group work and decreased during listening activities. Throughout a class period, GSR activity of the active-learning group showed increased trends compared with baseline measures, while the traditional lecture group showed decreased trends. Results indicate that GSR is a promising measure of real-time student engagement in the undergraduate classroom, bringing a new technique to discipline-based education researchers who aim to better measure student engagement; however, some limitations exist for broad-scale implementation.

Pupillary response to complex interdependent tasks: A cognitive-load theory perspective.

Pupil dilation is known to indicate cognitive load. In this study, we looked at the average pupillary responses of a cohort of 29 undergraduate students during graphical problem solving. Three questions were asked, based on the same graphical input. The questions were interdependent and comprised multiple steps. We propose a novel way of analyzing pupillometry data for such tasks on the basis of eye fixations, a commonly used eyetracking parameter. We found that pupil diameter increased during the solution process. However, pupil diameter did not always reflect the expected cognitive load. This result was studied within a cognitive-load theory model. Higher-performing students showed evidence of germane load and schema creation, indicating use of the interdependent nature of the tasks to inform their problem-solving process. However, lower-performing students did not recognize the interdependent nature of the tasks and solved each problem independently, which was expressed in a markedly different pupillary response pattern. We discuss the import of our findings for instructional design.

Salt Marsh Sediment Biogeochemical Response to the BP Blowout.

The impact of the blowout on salt marshes was investigated by observing the biogeochemistry in salt marsh sediments along the Gulf Coast. High sulfide levels due to hydrocarbon loading, increased microbial activity, and microbial community shifts can lead to plant browning and mortality. Sediment biogeochemical processes that degrade enriched carbon pools through sulfate reduction are primarily responsible for the biodegradation of spilled hydrocarbons. An assessment of the impact of contamination on salt marshes at Skiff Island, LA, and Cat Island, Marsh Point, and Saltpan Island, MS, was achieved through sediment electrode profiling, microbial community profiling, and quantification of hydrocarbon contamination, which captured the spatial sedimentary biogeochemical response that affects salt marsh productivity. At western locations (Skiff and Cat Islands), total petroleum hydrocarbons (TPHs) ranged from 2183 to 2996 mg kg, which was more than double the TPH concentration observed at eastern locales. At eastern study locations (e.g., Marsh Point), sedimentary pore-water HS concentrations were higher (maximum value = 231 mg L) and detected further up in the sediment column than at western locales (e.g., Skiff Island). Similarly, anaerobic and aerobic microbial activity, as measured by C substrate utilization profiles and well-color development, was as high or higher at eastern locations as compared with western locations. These results indicate that other factors besides location or degree of contamination, perhaps sedimentary dynamics and physical processes specific to each marsh, should be considered when determining salt marsh response to hydrocarbon contamination.