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Climate zones play a significant role in shaping the forest ecosystems located within them by influencing multiple ecological processes, including growth, disturbances, and species interactions. Therefore, delineation of current and future climate zones is essential to establish a framework for understanding and predicting shifts in forest ecosystems. In this study, we developed and applied an efficient approach to delineate regional climate zones in the northeastern United States and maritime Canada, aiming to characterize potential shifts in climate zones and discuss associated changes in forest ecosystems. The approach comprised five steps: climate data dimensionality reduction, sampling scenario design, cluster generation, climate zone delineation, and zone shift prediction. The climate zones in the study area were delineated into four different orders, with increasing subzone resolutions of 3, 9, 15, and 21. Furthermore, projected climate normals under Shared Socioeconomic Pathways 4.5 and 8.5 scenarios were used to predict the shifts in climate zones until 2100. Our findings indicate that climate zones characterized by higher temperatures and lower precipitation are expected to become more prevalent, potentially becoming the dominant climate condition across the entire region. These changes are likely to alter regional forest composition, structure, and productivity. In short, such shifts in climate underscore the significant impact of environmental change on forest ecosystem dynamics and carbon sequestration potential. 

Abstract Floodplains provide important ecological, hydrological, and geomorphic functions within river corridors. During overbank flows, complex hydrodynamic conditions occur as water exits and re‐enters the channel and interacts with hydraulically rough floodplain vegetation. However, the extent to which floodplain vegetation influences channel‐altering hydrodynamic forces and thus bedform topography and sediment transport is poorly understood. We address this knowledge gap and present the results of flume experiments where we measured bedform topography under varied floodplain vegetation conditions at two overbank flow relative depths. The experiments were conducted in a 1‐m wide meandering compound channel inset in a 15.4 long, 4.9‐m wide basin. The channel bed was a mobile sand‐and‐gravel mixture with a median sediment size of 3.3 mm, and sediment transport occurred only within the channel. We tested bare and vegetated floodplain conditions with 2.7‐cm diameter rigid emergent vegetation elements at spacings of 3.0 and 12.1 units m⁻². We performed a moving‐window analysis of topographic surface metrics including skewness, coefficient of variation, and standard deviation, as well as topographic patch analysis of area and contagion to measure changes in bedform heterogeneity as flow depth and vegetation density were varied. Our results show that both greater density vegetation and larger flows can increase bedform topographic heterogeneity. These findings suggest that floodplain vegetation and natural hydrologic regimes that include overbank flows can enhance stream habitat complexity. Designing for the effects of established vegetation conditions and prioritizing floodplain vegetation planting may be useful for river managers striving to achieve successful biomic river restoration. 

Abstract Widespread changes in the distribution and abundance of plant functional types (PFTs) are occurring in Arctic and boreal ecosystems due to the intensification of disturbances, such as fire, and climate-driven vegetation dynamics, such as tundra shrub expansion. To understand how these changes affect boreal and tundra ecosystems, we need to first quantify change for multiple PFTs across recent years. While landscape patches are generally composed of a mixture of PFTs, most previous moderate resolution (30 m) remote sensing analyses have mapped vegetation distribution and change within land cover categories that are based on the dominant PFT; or else the continuous distribution of one or a few PFTs, but for a single point in time. Here we map a 35 year time-series (1985–2020) of top cover (TC) for seven PFTs across a 1.77 × 10 6 km 2 study area in northern and central Alaska and northwestern Canada. We improve on previous methods of detecting vegetation change by modeling TC, a continuous measure of plant abundance. The PFTs collectively include all vascular plants within the study area as well as light macrolichens, a nonvascular class of high importance to caribou management. We identified net increases in deciduous shrubs (66 × 10 3 km 2 ), evergreen shrubs (20 × 10 3 km 2 ), broadleaf trees (17 × 10 3 km 2 ), and conifer trees (16 × 10 3 km 2 ), and net decreases in graminoids (−40 × 10 3 km 2 ) and light macrolichens (−13 × 10 3 km 2 ) over the full map area, with similar patterns across Arctic, oroarctic, and boreal bioclimatic zones. Model performance was assessed using spatially blocked, nested five-fold cross-validation with overall root mean square errors ranging from 8.3% to 19.0%. Most net change occurred as succession or plant expansion within areas undisturbed by recent fire, though PFT TC change also clearly resulted from fire disturbance. These maps have important applications for assessment of surface energy budgets, permafrost changes, nutrient cycling, and wildlife management and movement analysis. 

This Complete Research paper will describe the implementation of an introductory course (ENGR194) for first semester engineering students. The course is meant to improve retention and academic success of engineering first-year students in the College of Engineering at the University of Illinois at Chicago. The implementation of this course is part of an ongoing National Science Foundation (NSF) Scholarships in Science, Technology, Engineering, and Math (S-STEM) project. This paper reports on the impact of combinatorial enrollment in ENGR194 and a previously described two-week Summer Bridge Program (SBP) offered only for entering S-STEM scholars before their first semester. To measure the impact of this course on student retention and academic success, various evaluation metrics are compared for three separate Comparison Groups (C-Groups) of students. The results show that the ENGR194 course had a significant positive impact on the first-year retention rate. The results also revealed that students who participated in both ENGR194 and SBP (C-Group 1) made changes to their declared majors earlier than students who had only taken ENGR 123 or neither of the courses (C-Groups 2 and 3 respectively). Furthermore, students in C-Group 1 received better grades in math and science than their peers, and students in C-Groups 1 and 2 had significantly higher GPAs than their peers in C-Group 3. 

This paper provides detailed information for a poster that will be presented in the National Science Foundation (NSF) Grantees Poster Session during the 2020 ASEE Annual Conference & Exposition. The poster describes the progress and the state of an NSF Scholarships in Science, Technology, Engineering, and Math (S-STEM) project. The objectives of this project are to 1) enhance student learning by providing access to extra- and co-curricular experiences, 2) create a positive student experience through mentorship, and 3) ensure successful student placement in the STEM workforce or graduate school. S-STEM Scholars supported by this program receive financial, academic, professional, and social development via various evidence-based activities integrated throughout their four-year undergraduate degrees beginning during the summer prior to starting at the University. The paper describes the characteristics (demographics, high school GPA, ACT/SAT scores, etc.) of the Scholars supported by the S-STEM grant. The paper also provides information about the completed tasks of the project to date. The completed tasks include a system for recruiting academically talented and economically disadvantaged students, a Summer Bridge Program (SBP), a first semester introductory engineering course, and a system to recruit and maintain faculty mentors. The ongoing tasks include the execution of a service learning project course and a system for recruiting industry mentors. This paper reports detailed assessment and evaluation data about different project tasks and the academic success metrics of the Scholars. It also lists a set of recommendations based on the lessons learned in this S-STEM project.