2 Sep 2026

Effects of Activated Carbon Dosage for Aquatic Bioaccumulation Control in Dredged Material

Purpose: The purpose of this study was to evaluate the activated carbon (AC) dosage needed to reduce bioaccumulation of polychlorinated biphenyls (PCBs) in sediment. The study examined the effects of three dosages of AC, as a percentage of the dry weight of sediment and organic content in three amended sediments from Lake Erie, on the bioaccumulation of PCBs in an oligochaete.

2 Sep 2026

Riparian Model Evaluation in Beargrass Creek, Kentucky

Purpose: With the growing demand for ecological restoration and accompanying use of ecological models to inform decision-making, there is a pressing need for efficient and effective model evaluation procedures in restoration planning. Ecological complexity and diverse modeling frameworks (e.g., quantitative habitat models versus semiquantitative assessments versus qualitative professional judgment) each create challenges for the verification and validation of ecological forecasting tools. This study evaluates the effectiveness of a semiquantitative riparian assessment model, the Simple Model for Urban Riparian Function (SMURF), relative to herbaceous vegetation community data collected from Beargrass Creek in Louisville, Kentucky. Vegetation community metrics were collected at 15 sites, including species richness, diversity, and native versus invasive species composition. These metrics were compared to multiple SMURF outputs to evaluate model accuracy and reliability. Findings indicate that SMURF metrics are minimally predictive of the empirical vegetation metrics examined here (i.e., 5 of 32 models met criteria for statistical significance). However, vegetation-oriented components of the SMURF model more directly aligned with empirical observations, potentially indicating that the aggregation of many metrics in SMURF makes comparisons with empirical data inappropriate. This study demonstrates the challenges in evaluation of broad-scoped, multimetric indices like SMURF relative to empirical metrics for a particular taxonomic group. These findings also provide insight into the potential limits of commonly used semiquantitative methods for ecosystem assessment.

2 Sep 2026

A Web Application for Riparian Models (WARM)

Purpose: Riparian ecological models are widely used to support restoration planning, impact assessment, and mitigation, but many existing tools remain difficult to locate, interpret, and execute. This technical note documents the development of the Web Application for Riparian Models (WARM), a browser-based platform that compiles and executes nine previously developed riparian models in a standardized interface. WARM provides two primary capabilities: a model comparison tool that helps users identify appropriate models based on project characteristics and a suite of calculators that automate model execution with built-in error checking. All source code is maintained in publicly accessible repositories to support version control, transparency, and future expansion. This technical note describes the model selection process, software architecture, and evaluation procedures used to verify numerical accuracy and assess usability. By reducing technical barriers and centralizing access to riparian modeling tools, WARM improves the practicality and long-term shareability of ecological models for US Army Corps of Engineers (USACE) projects and other restoration applications.

2 Sep 2026

Workshop for Stream Restoration Design Approaches and Regulatory Integration

Abstract: The US Army Engineer Research and Development Center (ERDC) brought together stream restoration design experts, researchers, and regulatory staff for a two-day workshop in Huntington, West Virginia. The purpose of the workshop was to discuss how different stream restoration design philosophies align with ecological assessment tools and the crediting/debiting systems used by the US Army Corps of Engineers (USACE) regulatory groups. The event was part of a research project aimed at ensuring appropriate restoration practices are applied to specific landscape contexts, while also identifying and sharing best practices currently used by the restoration community. Focus was concentrated on evaluating the applicability and limits of existing approaches, such as alluvial and threshold channel designs, Stage 0/8 restoration, process-based restoration, and natural channel design, rather than developing new methodologies.

2 Sep 2026

General Salmonid Habitat Model: Phase 3—Model Evaluation, Application, and Documentation

Abstract: The US Army Corps of Engineers (USACE) currently operates and maintains water resource structures within many of the waterways that support anadromous fish species. USACE is required to assess the impacts and benefits to the environment of proposed water resource projects (i.e., levee maintenance or construction), including those to anadromous fish, during the planning process. Environmental assessments generally use ecological models to project changes to the environment under future without and future with proposed project plans. This report presents an evaluation of and application guidance for the general salmonid habitat model (salmonid model) to assist with those assessments. Potential applications of the salmonid model include assessing impacts from navigation, flood risk reduction, and hydroelectric operations as well as projecting environmental benefits from ecosystem restoration projects. The salmonid model can be used at multiple spatial scales, and it is sensitive to a range of proposed restoration actions. The model is generally applicable within watersheds that support anadromous fish species within the Pacific Northwest region of the US.

2 Sep 2026

Trajectories of Vegetative Parameters at Poplar Island Tidal Marsh Restoration Cells

Abstract: This special report presents trajectories derived from multiple vegetative parameters at Poplar Island, a marsh restoration project in Chesapeake Bay using beneficially used fine-grained, nutrient-rich dredged material from upper Chesapeake Bay. Long-term datasets of four vegetative metrics from seven fine-grained marsh restoration “cells,” ranging in age from 3 to 19 years postplanting, illustrate that aboveground vegetative growth is rapid but subject to diebacks in early years, finally recovering and reaching an equilibrium level commensurate with or above nearby native marshes in roughly 7–8 years without adaptive management actions. Belowground biomass, in contrast, develops more slowly over time, without the initial burst of biomass. Comparisons with the one Poplar Island cell created with sandy dredged material indicate a different trajectory pattern, with belowground biomass stronger in early years, and the aboveground biomass developing more gradually, but without the dieback events in years 2–4. These results suggest recommendations for restoration practitioners regarding the timing and criteria for monitoring and adaptive management.

2 Sep 2026

Explainability-Driven LangChain-Integrated Large Language Models and Knowledge Graphs for Multiagent Reinforcement Learning in Complex Air Combat Simulation

Abstract: This work advances multiagent reinforcement learning (MARL) for complex air combat by integrating methods that enhance decision-making and explainability. Using a realistic six-degrees-of-freedom aerial simulation built on the OpenAI Gymnasium framework, we investigate competitive agent interactions in dynamic scenarios. We apply explainability techniques to clarify agent behavior and interaction patterns. The MARL framework is further augmented with knowledge graphs, large language models, and modular orchestration using the LangChain framework. This combines data-driven learning with knowledge-driven reasoning to strengthen situational awareness, coordination, and interpretability. Experimental results indicate that this integration sustains competitive performance while enhancing transparency and human interpretability.

2 Sep 2026

Updating Ecological Modeling Within the US Army Corps of Engineers (USACE): Exploring Innovative Approaches and Implementation Strategies

Abstract: The US Army Corps of Engineers (USACE) engages in the planning, de-sign, construction, monitoring, and adaptive management of aquatic eco-system restoration projects. Like many organizations, USACE uses ecological models to inform decisions regarding ecosystem restoration and management. Most ecological modeling to support ecosystem restoration is conducted using habitat and other index models. However, these approaches have changed little in decades, while the field of ecology has seen the rapid growth of new modeling techniques with an array of applications. More advanced ecological models have the potential to align more closely with aquatic ecosystem restoration project objectives, provide more accurate predictions, and improve the communication of restoration benefits. This overview of modern ecological modeling approaches highlights promising ways to increase the use of advanced ecological models to sup-port ecosystem restoration. We describe the characteristics, benefits, and constraints of five ecological modeling families—agent-based models, population models, community models, connectivity/network models, and machine learning methods—and their applicability to ecosystem restoration projects. We also outline important considerations for selecting eco-logical models for a given scenario. Finally, we highlight promising avenues for increasing the use of contemporary modeling approaches, including the value of conducting targeted case studies, in light of project planning constraints.

2 Sep 2026

Floristic Quality Assessment Index: Background and Applications

Abstract: Many diversity indexes have been developed to describe the biodiversity and integrity of biological communities, and each index tells us something unique about that community. However, some studies have found that these metrics alone were inadequate for describing differences in quality among biological communities. The Floristic Quality Assessment Index (FQA) differs from most other indexes because it incorporates plant community composition along with species richness to describe an area’s biodiversity and ecological integrity. This report presents the history and background of the FQA and its various applications in the areas of natural resource management and research. Additionally, the report discusses the strengths and weaknesses of the FQA and presents examples of how to apply the FQA in the project planning processes. The FQA is a simple and effective means of distinguishing among sites with different ecological integrity and of monitoring restoration progress. It can be used in project planning to prioritize work areas, set project goals, and assess progress toward these goals. Incorporating the FQA into project planning embeds ecological integrity and biodiversity into project objectives, ensuring that restoration projects contribute to the long-term health and sustainability of natural areas.

1 Sep 2026

Sand Nourishments: Review of Research and Introduction of the SOURCE Project

Abstract: Sand nourishments have become a popular management option to mitigate coastal retreat for sites with abundant sand supplies. Off-site sand is placed on the dry beach or under water at typical water depths up to 10 m. This nearshore zone has a high bed level variability and contains a cascade of morphological features. This makes the understanding and forecasting of nourishment morphodynamics and impacts challenging. The emerging climate-change effects, sea-level rise in particular, call for significant progress on this topic in due time. This paper presents an overview of field, laboratory and modeling studies on nourishment morphodynamics. Four key knowledge gaps were identified. First, the spreading of nourished sand through the coastal zone is poorly understood, and has not been quantified. Second, it is unclear how design variables such as size, placement location and grain-size affect the nourishment lifetime, spreading and impact. Third, the cumulative effect of repeated nourishments on the coastal system is unknown. Fourth, models are not capable to reliably predict the morphological development and impact of nourishments. To tackle these knowledge gaps, we have launched the SOURCE research project.