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This poster displays results from a project supported by an NSF grant to enhance interdisciplinary collaboration in civil and environmental engineering education. In its second year, part of the project focused on improving team science competencies within the core research group. Key activities included workshops on collaborative writing and grant writing best practices. The team attended a Science of Team Science (SciTS) workshop to refine collaboration skills and responded to the Teaming Readiness Survey, which revealed strengths in valuing expertise but identified areas for improvement, such as role clarity and effective communication. In addition, the team responded to a Social Network Analysis Survey that showcased a growing network of research ties, indicating a robust collaborative environment, particularly among Principal Investigators. The preliminary results highlight a development in the team’s effectiveness and psychological safety ratings, fostering trust and collaboration. The social network evolved from professional to social connections, with new members gradually integrating into the team. The research team concludes that focusing on collaborative skills and effective communication strengthens interdisciplinary collaboration in the changing scientific landscape. 

The Center for Infrastructure Transformation and Education (CIT-E) is a community of faculty members who share a passion for infrastructure education. Their goal is to transform the way civil and environmental engineering (CEE) topics are taught. In 2021, the co-authors of this poster received an NSF IUSE grant to build the capacity of a faculty community of practice (CoP), positioning it to transform the approach to diversity, equity, inclusion, and justice (DEIJ) in CEE education. By incorporating DEIJ into their teaching, research, and service commitments, CEE faculty members can be the catalysts responsible for transitioning our nation’s inequitable infrastructure into equitable infrastructure. This poster highlights three key assessment objectives, including a review of the literature on re-contextualizing infrastructure education, a SWOT analysis, and team science professional development. 

A national faculty Community of Practice (CoP) has created a model course for undergraduate infrastructure education as a part of its shared agenda. This CoP has collectively defined the domain of knowledge for undergraduate introductory infrastructure education; co-created and peer-reviewed more than 40 complete lessons for an introductory infrastructure course; shared best practices and resources among members; and provided mentorship to newer members adopting or adapting the materials. The Center for Infrastructure Transformation and Education (CIT-E) considers infrastructure as a system rather than a collection of unrelated structural/environmental/transportation components; even more importantly, this system is conceived of as a social-technical system that must be designed with equity and justice factors prioritized to include the diversity of users’ lived experiences. To that end, CoP members have recently produced learning materials on Equity, Inclusion, and Justice (DEIJ) in infrastructure provision. The operationalizing of CoP as a theory of change by CIT-E has emerged beyond the initial National Science Foundation (NSF) funding a decade ago, employing various change strategies. Example strategies include expanding membership and creating alternative educational practices to support change and transformation. Recent NSF funding and new membership have created opportunities for the CoP to lead change at a much broader level across civil and environmental engineering education in the U.S. As part of this work, we conducted semi-structured interviews with seven change leaders in engineering education and DEIJ. We asked their perspectives on community of practice as a theory of change and whether it is appropriate for this work. Their responses were coded, revealing 169 codes, some of which advisors agreed upon, and many representing alternative perspectives. Processes such as considering, accepting, asking, and acknowledging are easy to overlook while executing change through mentoring, funding, and doing. The results of this work are helpful for civil and environmental engineering (CEE) faculty members interested in operationalizing change in their classroom and on their campus to meet ABET’s relatively recent DEI criteria, and the process in this study is transferrable to other fields that are also mobilizing transformative practices for integrating DEIJ principles into their curricula. 

Tree growth and longevity trade-offs fundamentally shape the terrestrial carbon balance. Yet, we lack a unified understanding of how such trade-offs vary across the world’s forests. By mapping life history traits for a wide range of species across the Americas, we reveal considerable variation in life expectancies from 10 centimeters in diameter (ranging from 1.3 to 3195 years) and show that the pace of life for trees can be accurately classified into four demographic functional types. We found emergent patterns in the strength of trade-offs between growth and longevity across a temperature gradient. Furthermore, we show that the diversity of life history traits varies predictably across forest biomes, giving rise to a positive relationship between trait diversity and productivity. Our pan-latitudinal assessment provides new insights into the demographic mechanisms that govern the carbon turnover rate across forest biomes. 

Abstract The emergence of alternative stable states in forest systems has significant implications for the functioning and structure of the terrestrial biosphere, yet empirical evidence remains scarce. Here, we combine global forest biodiversity observations and simulations to test for alternative stable states in the presence of evergreen and deciduous forest types. We reveal a bimodal distribution of forest leaf types across temperate regions of the Northern Hemisphere that cannot be explained by the environment alone, suggesting signatures of alternative forest states. Moreover, we empirically demonstrate the existence of positive feedbacks in tree growth, recruitment and mortality, with trees having 4–43% higher growth rates, 14–17% higher survival rates and 4–7 times higher recruitment rates when they are surrounded by trees of their own leaf type. Simulations show that the observed positive feedbacks are necessary and sufficient to generate alternative forest states, which also lead to dependency on history (hysteresis) during ecosystem transition from evergreen to deciduous forests and vice versa. We identify hotspots of bistable forest types in evergreen-deciduous ecotones, which are likely driven by soil-related positive feedbacks. These findings are integral to predicting the distribution of forest biomes, and aid to our understanding of biodiversity, carbon turnover, and terrestrial climate feedbacks. 

Abstract AimAmazonia hosts more tree species from numerous evolutionary lineages, both young and ancient, than any other biogeographic region. Previous studies have shown that tree lineages colonized multiple edaphic environments and dispersed widely across Amazonia, leading to a hypothesis, which we test, that lineages should not be strongly associated with either geographic regions or edaphic forest types. LocationAmazonia. TaxonAngiosperms (Magnoliids; Monocots; Eudicots). MethodsData for the abundance of 5082 tree species in 1989 plots were combined with a mega‐phylogeny. We applied evolutionary ordination to assess how phylogenetic composition varies across Amazonia. We used variation partitioning and Moran's eigenvector maps (MEM) to test and quantify the separate and joint contributions of spatial and environmental variables to explain the phylogenetic composition of plots. We tested the indicator value of lineages for geographic regions and edaphic forest types and mapped associations onto the phylogeny. ResultsIn the terra firme and várzea forest types, the phylogenetic composition varies by geographic region, but the igapó and white‐sand forest types retain a unique evolutionary signature regardless of region. Overall, we find that soil chemistry, climate and topography explain 24% of the variation in phylogenetic composition, with 79% of that variation being spatially structured (R² = 19% overall for combined spatial/environmental effects). The phylogenetic composition also shows substantial spatial patterns not related to the environmental variables we quantified (R² = 28%). A greater number of lineages were significant indicators of geographic regions than forest types. Main ConclusionNumerous tree lineages, including some ancient ones (>66 Ma), show strong associations with geographic regions and edaphic forest types of Amazonia. This shows that specialization in specific edaphic environments has played a long‐standing role in the evolutionary assembly of Amazonian forests. Furthermore, many lineages, even those that have dispersed across Amazonia, dominate within a specific region, likely because of phylogenetically conserved niches for environmental conditions that are prevalent within regions. 

Abstract Amazonia’s floodplain system is the largest and most biodiverse on Earth. Although forests are crucial to the ecological integrity of floodplains, our understanding of their species composition and how this may differ from surrounding forest types is still far too limited, particularly as changing inundation regimes begin to reshape floodplain tree communities and the critical ecosystem functions they underpin. Here we address this gap by taking a spatially explicit look at Amazonia-wide patterns of tree-species turnover and ecological specialization of the region’s floodplain forests. We show that the majority of Amazonian tree species can inhabit floodplains, and about a sixth of Amazonian tree diversity is ecologically specialized on floodplains. The degree of specialization in floodplain communities is driven by regional flood patterns, with the most compositionally differentiated floodplain forests located centrally within the fluvial network and contingent on the most extraordinary flood magnitudes regionally. Our results provide a spatially explicit view of ecological specialization of floodplain forest communities and expose the need for whole-basin hydrological integrity to protect the Amazon’s tree diversity and its function. 

Tree diversity and composition in Amazonia are known to be strongly determined by the water supplied by precipitation. Nevertheless, within the same climatic regime, water availability is modulated by local topography and soil characteristics (hereafter referred to as local hydrological conditions), varying from saturated and poorly drained to well‐drained and potentially dry areas. While these conditions may be expected to influence species distribution, the impacts of local hydrological conditions on tree diversity and composition remain poorly understood at the whole Amazon basin scale. Using a dataset of 443 1‐ha non‐flooded forest plots distributed across the basin, we investigate how local hydrological conditions influence 1) tree alpha diversity, 2) the community‐weighted wood density mean (CWM‐wd) – a proxy for hydraulic resistance and 3) tree species composition. We find that the effect of local hydrological conditions on tree diversity depends on climate, being more evident in wetter forests, where diversity increases towards locations with well‐drained soils. CWM‐wd increased towards better drained soils in Southern and Western Amazonia. Tree species composition changed along local soil hydrological gradients in Central‐Eastern, Western and Southern Amazonia, and those changes were correlated with changes in the mean wood density of plots. Our results suggest that local hydrological gradients filter species, influencing the diversity and composition of Amazonian forests. Overall, this study shows that the effect of local hydrological conditions is pervasive, extending over wide Amazonian regions, and reinforces the importance of accounting for local topography and hydrology to better understand the likely response and resilience of forests to increased frequency of extreme climate events and rising temperatures.