15 Sep 2025

Foliar Fungal Assemblages Associated with Diploid and Triploid Butomus umbellatus Populations in the United States

Purpose: Novel associations between plant invaders and fungi may moderate invader impacts if fungi are pathogenic or contribute to variation in invader response to management. Identifying and quantifying species associations with plant invaders can have management consequences. However, whether novel fungal associations and resulting assemblages are shaped by invader genetics is largely unknown. The goal of this research was to identify community patterns of foliar fungi associated with diseased and healthy diploid and triploid Butomus umbellatus (flowering rush) cytotypes in the United States. A total of 12 diploid and 9 triploid Butomus umbellatus L. populations in 10 states across the northern United States were surveyed, foliar fungi were isolated from healthy and diseased leaves, and a fungal assemblage structure analysis was conducted to determine whether assemblages were unique to B. umbellatus cytotypes. Differences in flowering rush–associated fungal assemblages and complex interaction between fungal taxa may promote uneven invasion between cytotypes in the United States and guide future management efforts to reduce the negative impacts caused by B. umbellatus invasions.

15 Sep 2025

Standard Operating Procedures for the Design, Construction, and Maintenance of Linear Infrastructure in Fens in Cold Regions

Abstract: In Alaska and across the Arctic and Subarctic, winter conditions can enable the expansion of linear infrastructure across the frozen landscape of fen wetlands. This expands military training opportunities into lowland wet, boggy, mostly impassable terrain. However, there are personnel, civilian, and environmental risks from using fens as travel corridors and drop zones. The effective design, construction, operation, and maintenance of such infrastructure on fens supports the dual mandate of troop training to fulfill the mission and protect the environment. This Technical Report (TR) addresses the risks of the establishment and use of linear infrastructure on the DoD lands in Alaska and in other austere cold environments where the DoD operates. This TR is founded on a review of methods used by US Army Installations, focusing primarily on Fort Wainwright in Interior Alaska. It establishes basic standard operating procedures (SOPs) by drawing on federal agency and international best practices and emerging research in circumpolar regions and beyond. This TR serves as a reference document for military land and infrastructure planners and unit leadership to create and maintain linear infrastructure on fens as environmental challenges evolve and opportunities develop to further the Army mission in high latitude environments.

15 Sep 2025

Standard Operating Procedures for the Design, Maintenance, and Operation of Freshwater Ice Bridges

Abstract: Operations in cold regions inevitably require maneuvering across, through, or atop frozen surfaces. Ice bridges are special components of winter linear infrastructure that can have significant impacts on mission targets. Proper siting, design, monitoring, and operation of ice bridges reduces potential environmental impacts and decreases risks to personnel and equipment. The US Army operates multiple ice bridge crossings on training lands in Alaska and collaborates with other countries in training events that use them. They are a likely means of travel for potential operations in cold regions. However, the US Army lacks up to date guidance on the design, maintenance, and operation of ice bridges. This report addresses this need by providing a set of standard operating procedures that have been developed from a broad synthesis of ice bridge usage in northern regions. In addition, it reviews all relevant historic and current literature regarding ice bridges, describes risk assessment and mitigation techniques for ice bridge operations, discusses specific considerations for US Army training areas in Alaska, and briefly describes important ramifications of changing weather conditions and increasing uncertainty as they relate to ice bridge life span.

15 Sep 2025

Fiber-Reinforced-Polymer (FRP) Composite Sandwich Panel Barge Impact Modeling and Repair Testing: Dynamic and Static Finite Element Analysis (FEA) Predictions for Impact and Flexural Testing Validated with Experiments

Abstract: The US Army Engineer Research and Development Center has studied the functionality, durability, and structural integrity of fiber-reinforced-polymer (FRP) composite materials in civil works infrastructure. Compared to traditional materials like steel, composites offer a high strength-to-density ratio and excellent resistance to environmental degradation. The purpose of this study is to evaluate the dynamic response of FRP composite sandwich panels subjected to a barge impact with typical masses and velocities. A finite element model was created for FRP composite sandwich panels by incorporating cohesive interaction properties to evaluate the damage between three-dimensional (3D) layers. To validate the model, several FRP composite sandwich panels were experimentally subjected to low-velocity impacts and compared to the models. Moreover, flexural experiments were performed to determine the reduction of structural performance after impact and the efficacy of two different repair methods. Numerical predictions were developed to explore the damage caused by the interfaces of FRP composite layers. Load, deflection, and velocities were obtained experimentally and with finite element models.

12 Sep 2025

Veterans Administration Fourth Generation Historic Context

Abstract: The period of significance for fourth generation of Veterans Administration (VA) medical centers ranges from 1955 to 1977. This period encapsulates a surge of VA medical center construction with congressional funding, dating from the release of the 1955 congressional report Nonbed Betterments in Veterans Administration Hospitals—Need for Renovation and Construction to the adoption of the Veterans Administration Medical Facilities Acquisition Act of 1977. New medical centers constructed by the VA during this time may be eligible under Criterion A for their association with health care and medicine, specifically the development of education and research relationships with medical schools. These partnerships advanced therapies, technology, and hospital operation in support of the VA’s mission to provide quality medical care for veterans. To support these partnerships, VA medical centers were commonly built adjacent to or within medical school complexes. Additionally, fourth generation VA medical centers may be eligible under Criterion C for embodying distinctive architecture or landscape architecture characteristics of mid-century modern hospitals or representing an important contribution in a significant architect’s career. This report provides a comprehensive historic context for the design, construction, and operation of new fourth generation VA medical centers in support of Section 110 of the National Historic Preservation Act of 1966 (NHPA). It does not include other VA medical facilities constructed during this period, such as psychiatric and rehabilitation centers, nursing homes, domiciliaries, and research and education buildings.

12 Sep 2025

Arkansas City to Vicksburg Adaptive Hydraulics Model

PURPOSE: The purpose of this study is to develop and validate a 2D, depth-averaged hydrodynamic model of the Mississippi River from Vicksburg, Mississippi, to Arkansas City, Arkansas, to accurately replicate low-flow conditions. The model will be used to support an ongoing effort for the development of a low-water forecast model to aid navigational resilience.

12 Sep 2025

Identifying Hydric Soils Using α,α′-Dipyridyl Dye

Purpose: The application of α,α′-dipyridyl dye (pronounced alpha, alpha di-peeri-dill) provides a reliable and defensible mechanism for documenting the presence of reduced iron in support of hydric soil identification and wetland delineation activities. The α,α′-dipyridyl dye has proven particularly useful for identifying hydric soils in naturally problematic, altered, and disturbed soils. The proper application of paper test strips embedded with α,α′-dipyridyl dye further promotes the use of this technique to improve wetland delineation and management. This technical note summarizes the state of the science related to α,α′-dipyridyl dye and provides practitioner recommendations for applying, documenting, and interpreting α,α′-dipyridyl dye in hydric soil and wetland investigations.

12 Sep 2025

Quantifying Wild Pig Damage Reduction Using Before-After-Control-Impact Design at USACE Richard K. Yancey, Louisiana

Abstract: The FY23 research presented in this report is year three of a 3-year research plan to develop a user-friendly ecological-economic framework for rapid assessment of wild pig damage to wetlands. Building off research and findings from the FY21 and FY22 efforts conducted at Somerville Lake, Texas, the FY23 research focused on adapting the sampling frame-work to a forested wetland using a more advanced method for the extrapolation of damage to the whole study area, refining the economic valuation approach with machine-learning techniques, and improving the setup of the before-after-control-impact (BACI) study design estimating damage reduction after a targeted control effort. We estimate that the benefits provided by wetlands lost to wild pigs over a 1-year period in the Richard K. Yancey Wildlife Management Area study area was $234,486 (80% confidence interval, $63,155 to $691,220), and the aerial gunning control effort in the treatment plot provided a 243% return on investment in terms of damages avoided to wetlands.

12 Sep 2025

Literature Review and Environmental Concerns Regarding Lithium-Ion Batteries

Abstract: This study investigates the environmental and technical challenges associated with the production, use, and recycling of lithium-ion batteries (LIBs), which are critical components in consumer electronics and electric vehicles (EVs). As the demand for LIBs continues to grow, the concerns related to the mining and processing of key materials like lithium, cobalt, nickel, and manganese are also increasing. The extraction and refining processes for these metals are energy-intensive and produce significant environmental impacts, including greenhouse gas emissions, toxic waste, and resource depletion. The review emphasizes the need for improved recycling technologies and sustainable practices to mitigate the environmental footprint of LIBs and secure a more sustainable supply chain for the future of clean energy storage solutions. This study also analyzes LIB components to assess the presence of environmentally hazardous metals and compounds. Advanced analytical techniques like X-ray fluorescence (XRF), inductively coupled plasma–optical emission spectroscopy (ICP-OES), and Fourier transform infrared (FTIR) spectroscopy revealed significant leaching of toxic elements and PFAS from battery parts, underscoring the environmental and health risks associated with improper disposal. The findings highlight the urgent need for improved recycling methods to mitigate these risks and enhance the sustainability of LIB use.

11 Sep 2025

Influence and Mechanisms of Mineral Chemistry and Sizing Effects on Cementitious and Pozzolanic Reactions

Abstract: This study investigated whether materials traditionally considered inert could become reactive with increased fineness. Researchers used multiple techniques to produce materials in a variety of fineness levels. The final products were then analyzed for pozzolanic reactivity in accordance with ASTM 1897 and for their influence on portland cement hydration in accordance with ASTM C1702. Results indicated that pozzolanic reactivity was not produced by successive grinding for either chemistry, at least within the limits of the techniques used. Both chemistries were shown to influence the rate of portland cement hydration when ground finer than cement. This phenomenon is known as the filler effect, and it became more significant with increased fineness.