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.

10 Sep 2025

Light Availability Calculator for Identifying Suitable Habitat for Light-Limited Aquatic Vegetation

Purpose: The purpose of this Ecosystem Management and Restoration Research Program Technical Note (EMRRP TN) is to introduce a geospatial Light Availability Calculator, designed to inform suitable habitat selection for light-limited, submerged aquatic vegetation (SAV) species. The need and intended use for the Light Availability Calculator is first described. Then, the scientific and mathematical formulations underpinning the calculator are explained. Finally, recommendations for calculator inputs reflective of various user needs (simple and rapid versus complex and time intensive) are described.

8 Sep 2025

US Army Corps of Engineers Aquatic Restoration Monitoring for Ecosystem Recovery (ARMER) Network

Abstract: Long-term, high-quality ecosystem restoration monitoring is essential to achieve recovery and maximize restoration investments. However, there are many challenges associated with restoration monitoring that inhibit effective collection, storage and management, communication, and utilization of ecosystem recovery information. A nationwide monitoring network of restoration and reference sites is needed to generate high-quality, replicated datasets to address large-scale ecosystem restoration challenges. The US Army Corps of Engineers (USACE) makes significant annual investments in ecosystem restoration projects and monitoring for adaptive management under their aquatic ecosystem restoration mission, and thus, is uniquely positioned to lead the development of an ecosystem recovery monitoring network. Investments in large-scale, long-term data collection and management would allow USACE to (1) improve data consistency and data replication to reduce uncertainty in ecological recovery assessments, (2) demonstrate the socioecological benefits of restoration to better inform future restoration investments, and (3) improve the USACE’s ability to publicly communicate returns on investments and the nationwide value of aquatic ecosystem restoration. This report details a roadmap for how USACE could leverage aquatic ecosystem restoration investments to operationalize the USACE Aquatic Restoration Monitoring for Ecosystem Recovery (ARMER) Network and advance the science of aquatic ecosystem restoration.

4 Sep 2025

The Edge of Crisis: Discovery of Young of Year Black Carp Mylopharyngodon piceus (Richardson, 1846) in the Lower Mississippi River

Abstract: Understanding changes in the status of invasive species is important to managers in order to prevent or minimize impacts to native communities. Out of the four invasive carp imported to the U.S. from Eastern Asia, black carp Mylopharyngodon piceus have been generally overlooked due to the difficulty in capturing these fish even using targeted efforts. Because of this, limited resources have been channeled towards managing this species. Concerns over the expansion of black carp have been expressed, but direct evidence of reproduction in U.S. waters was lacking until young of year black carp were caught in tributaries of the Middle Mississippi River in 2015. This remained the known extent of the naturalized invasion until fish community surveys conducted in the fall of 2022 and 2023 documented young of year black carp in three oxbow lakes connected to the mainstem Lower Mississippi River. These collections provide evidence for increased population growth and exhibit expanding threats to the diverse mussel communities native to the Lower Mississippi River basin.

3 Sep 2025

Acute Toxicity of Carbon Nanotubes, Carbon Nanodots, and Cell-Penetrating Peptides to Freshwater Cyanobacteria

Abstract: Synthetic non-metallic nanoparticles have been explored to treat harmful algal blooms, but their strain-specific algicidal activities have been rarely investigated. Three batches of CNDs were prepared in-house using glucose or chloroform and methanol as the substrate and one batch of single-walled CNTs. The axenic laboratory culture of each cyanobacterial strain was exposed to an NMNP at two dosage levels for 48 h, followed by measurement of five endpoints. The endpoints were optical density at 680 nm for chlorophyll-a estimation, OD at 750 nm for cell density, instantaneous pigment fluorescence emission after being excited with 450 nm blue light for chlorophyll-a or 620 nm red light for phycocyanin, and quantum yield for photosynthesis efficiency of photosystem II. The results indicate the acute toxicity was strain-, NMNP type-, dosage-, and endpoint-dependent. The two benthic strains were more resistant to NMNP treatment. SWCNTs and fraction A14 of CND-G were more toxic than CND-G and CND-C/M. The CPP was the least toxic. The high dose generally caused more severe impairment. OD750 and OD680 were more sensitive and QY was the least sensitive. The strain dependence of toxicity suggested the potential application of these NMNPs as a target-specific tool for mitigating harmful cyanobacterial blooms.

29 Aug 2025

Nanofiber Fabrication by Electrospinning Technology: Optimization, Characterization, and Application

Abstract: This project explores electrospinning (ES) as one of the most successful technologies to produce nanofiber materials. Electrospun nanofibers are used in various military technologies, including advanced filtration systems, impact-resistant protective gear, thermal insulation, radar absorption for camouflage and stealth, antimicrobial wound dressings, drug-delivery patches, rapid healing, efficient solar cells, and self-cleaning materials for regeneration. Researchers at the US Army Engineer Research and Development Center (ERDC) investigated electrospinning effects on morphology, crystallinity and distribution of metal oxides for photocatalytic activities, and magnetic and mechanical properties in reinforcing composites. This study includes the following fabricated electrospun mats: -iron and titanium oxide (Fe3O4 and TiO2) with polyvinyl alcohol (PVA) -graphene, graphene oxide, and reduced graphene oxide with polyvinylidene fluoride (PVDF) -graphene-polyacrylonitrile (PAN) -metal-organic frameworks (MOF), graphene-MXene with PAN The research presented herein includes electrospinning theory, process, and parameters; sol–gel technology in solution preparation; and electrospinning sample characterization to guide readers in the fabrication of electrospun fibers with targeted characteristics. Future studies explore electrospun MOFs and MXene, a class of two-dimensional inorganic compounds with transition metal carbides, nitrides, or carbonitrides composites. These studies are invaluable for advancing military programs and enhancing warfighter support and civil works.

29 Aug 2025

Developing Conceptual Ecological Models for Hydraulic Analysis

Purpose: Technological advances, coupled with increased availability of spatial and monitoring data for hydraulic analysis, environmental flows analysis, and remote sensing, present opportunities for novel investigations of the structure and function of ecological systems. To leverage these capabilities in ecological analysis, it is necessary to develop a framework that links engineering model capacities with ecological principles. It is well known that riverine ecosystems are complex systems at the intersection of channel form, stream flow volume, and biology. However, because of differences in technical language and analytical philosophy, there are practical challenges associated with cross-walking multidiscipline riverine studies into interdisciplinary efforts that comprehend both engineering and ecological principles. Challenges associated with cross-discipline communication and framing the scope of ecohydraulic analysis are inherent barriers that limit the traction of research crossing disciplinary boundaries.

29 Aug 2025

Monitoring of Understudied Wetlands: State of Knowledge

Abstract: Some wetlands can present unique challenges for mapping and monitoring due to their size, location, foliage architecture, and spectral characteristics. For instance, assessing ecological condition and restoration success using traditional remote-sensing systems in forested and ephemeral wetlands is onerous. Therefore, the purpose of this technical note is to evaluate the state of knowledge and technology related to the use of remote sensing in assessing vegetation dynamics in understudied and hard to monitor wetlands. Ultimately, this exercise will identify data gaps and recommend improvements for analyzing and modeling wetland systems and trends, quantifying disturbance impacts, and assist efficiencies of data collection to improve management decisions, which in turn will help in reaching restoration goals.