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Abstract Recently classified as a unique species by the IUCN, African forest elephants (Loxodonta cyclotis) are critically endangered due to severe poaching. With limited knowledge about their ecological role due to the dense tropical forests they inhabit in central Africa, it is unclear how the Afrotropics are influenced by elephants. Although their role as seed dispersers is well known, they may also drive large‐scale processes that determine forest structure through the creation of elephant trails and browsing the understory, allowing larger, carbon‐dense trees to succeed. Multiple scales of lidar were collected by NASA in Lopé National Park, Gabon from 2015 to 2022. Utilizing two airborne lidar datasets in an African forest elephant stronghold, detailed canopy structural information was used in conjunction with elephant trail data to determine how forest structure varies on and off trails. Forest along elephant trails displayed different structural characteristics than forested areas off trails, with lower canopy height, canopy cover, and different vertical distribution of plant density. Less plant area density was found on trails at 1 m in height, while more vegetation was found at 12 m, compared to off trail locations. Trails in forest areas with previous logging history had lower plant area in the top of the canopy. Forest elephants can be considered as “logging light” ecosystem engineers, affecting canopy structure through browsing and movement. Both airborne lidar scales were able to capture elephant impact along trails, with the high‐resolution discrete return lidar performing higher than waveform lidar. 

In any research computing (RC) environment, the role of the user support group is a combination of education, consulting, and outreach. As this role is the most public-facing of a research computing group's team, it is important to ensure an excellent level of support is provided to users. The Research Computing group at the University of Colorado (CURC) Boulder maintains a large-scale computing cluster with several hundred active users, among other services, and has done so since 2011. The user support group at CURC provides a variety of services intended to support these users. This paper describes those services the CURC group provides, as well as explores the various ways that these services have been improved in 2018-19. The impact on users is also assessed. 

Abstract Arctic warming can influence tundra ecosystem function with consequences for climate feedbacks, wildlife and human communities. Yet ecological change across the Arctic tundra biome remains poorly quantified due to field measurement limitations and reliance on coarse-resolution satellite data. Here, we assess decadal changes in Arctic tundra greenness using time series from the 30 m resolution Landsat satellites. From 1985 to 2016 tundra greenness increased (greening) at ~37.3% of sampling sites and decreased (browning) at ~4.7% of sampling sites. Greening occurred most often at warm sampling sites with increased summer air temperature, soil temperature, and soil moisture, while browning occurred most often at cold sampling sites that cooled and dried. Tundra greenness was positively correlated with graminoid, shrub, and ecosystem productivity measured at field sites. Our results support the hypothesis that summer warming stimulated plant productivity across much, but not all, of the Arctic tundra biome during recent decades. 

Advances in the volume, diversity, and complexity of research data and associated workflows requires enhanced capabilities to access, secure, reuse, process, analyze, understand, curate, share, and preserve data. To address this need at the regional level the University of Colorado, Colorado State University, and the University of Utah formed a "Cyberteam" in 2017 to provide cyberinfrastructure (CI) support to researchers at institutions in the Rocky Mountain Advanced Computing Consortium (RMACC) encompassing states across the Intermountain West. The Cyberteam is comprised of CI professionals across the three institutions who collaborate closely, sharing expertise and resources. Since its establishment, the Cyberteam has worked to broaden accessibility and options for computing, storage, and data publishing for RMACC researchers; enhance training on data- and workflow-oriented topics; improve engagement with researchers using CI; and better understand user needs and challenges. One key accomplishment has been the development of a series of focus group and survey instruments to achieve better understanding the CI needs and challenges of researchers across a diverse spectrum of disciplines. This paper provides an overview of the RMACC Cyberteam's objectives, accomplishments, challenges, and future direction.