Engineer Research and Development Center News Releases

Estimating the Density of Secretive, At-risk Snake Species on DoD Installations Using an Innovative Approach: IDEASS

Press Operations — Wed, 14 Oct 2020 12:52:20 GMT

Abstract: The Department of Defense (DoD) expends considerable resources managing and conserving threatened, endangered, or at-risk snake species. Management for these species is often hampered by a lack of basic knowledge regarding their population size and trajectory. The low detectability of most snakes makes it difficult to determine their presence, or to employ traditional methods to estimate abundance. This work demonstrated a novel, simulation-based method, Innovative Density Estimation Approach for Secretive Snakes (IDEASS), for estimating snake density based on systematic road surveys, behavioral observations of snake movement, and spatial movement (radio telemetry) data. This method was used to generate meaningful density estimates for two rare and cryptic snakes of conservation concern, the Southern Hognose and Eastern Diamondback Rattlesnake, at Fort Stewart, Georgia. IDEASS was also applied to an existing dataset to retroactively estimate density of a more common species of management concern, the Western Ratsnake, at Fort Hood, Texas. In all three cases, traditional density estimation via visual surveys and capture-mark-recapture (CMR) failed completely due to lack of captures and re-captures, despite extensive field effort. We conclude that IDEASS represents a powerful tool, and in some cases the only viable method, for estimating density of secretive snakes.

Eutrophication Management via Iron-Phosphorus Binding

Press Operations — Thu, 01 Oct 2020 14:54:34 GMT

Abstract: The presence of phosphorus (P) in excessive quantities can lead to undesired conditions, such as cyanobacterial/algal bloom. The over-enriched hypertrophic conditions or the excess amounts of nutrients (nitrogen and P, P being the primary nutrient of concern) are the major cause of harmful cyanobacterial blooms, which can be toxic and can also lead to oxygen depletion and anoxic respiration (hypoxia) in the hypolimnion. The presence of iron compounds has been shown to bind phosphorus and diminish harmful algal blooms. Therefore, an iron-plates-packed reactor has been designed to reduce P in surface water. This cost-effective and easy-to-install system has shown promising results in phosphorus reduction.

Development of a General Anadromous Fish Habitat Model: Phase 2: Initial Model Quantification

Press Operations — Thu, 01 Oct 2020 14:38:36 GMT

Abstract: The General Anadromous Fish Habitat Model (now the General Salmonid Habitat Model) was developed to assist in the plan formulation process for ecosystem restoration and mitigation projects. The model generates relative differences in habitat quality between proposed alternative future scenarios. In order to provide model development transparency, this report presents the initial quantification phase of the model development process. The draft model depicted in this report is scalable, meaning various parameters may be measured at different landscape scales (for example, reach vs. watershed). The model can be applied (model domain) in watersheds that currently or previously supported salmonid fish species. Application outside of the model domain would need further evaluation to ensure appropriate sensitivity to the new system of interest. Although the model is being developed to explicitly capture changes in fish habitat in response to restoration actions, this model would be appropriate for use in any planning project focused on the restoration of streams, rivers and, estuaries (for example, dam removals, in-stream habitat enhancement), because the parameters are measures of ecosystem level structure, function, and process.

Acid Sulfate Soils in Coastal Environments: A Review of Basic Concepts and Implications for Restoration

Press Operations — Thu, 01 Oct 2020 14:30:11 GMT

Abstract: Acid sulfate soils naturally occur in many coastal regions. However, the oxidation of acid sulfate soils can decrease soil pH to <4.0, affecting vegetation and aquatic organisms. Acid sulfate soil oxidation typically occurs where anaerobic sediments or soils were exposed to aerobic conditions (for example, extended drought, artificial drainage, or dredged material placement in upland areas). Recently, field observations documented the formation of acid sulfate materials at multiple degraded marsh restoration locations (Rhode Island, New Jersey, California) following intentional dredged sediment placement into wetland environments designed to increase marsh elevation. Unlike previous studies of acid sulfate soils, the in situ dredged material did not contain acid sulfate–bearing materials at the time of placement; instead, the interaction between the marsh substrate and the overlying dredged material appears to have caused the formation of acid sulfate soils. These findings highlight the need for additional studies of acid sulfate soil formation and fate—especially within a marsh restoration context. In response, this report provides a review of literature related to acid sulfate soils, discusses preliminary data collected to evaluate acid sulfate material formation following marsh restoration, and identifies knowledge gaps requiring additional research and technical guidance.

Aligning Research and Management Priorities for Nitellopsis obtusa (Starry Stonewort)

Press Operations — Thu, 01 Oct 2020 14:24:39 GMT

Abstract: In 2018, the US Army Corps of Engineers and Washington and Waukesha Counties in Wisconsin hosted a workshop on the invasive macroalga starry stonewort (Nitellopsis obtusa). Leading water resource managers (agencies and commercial applicators), researchers, regulators, and other interested parties discussed issues surrounding starry stonewort invasions in the Great Lakes Region (GLR). Technical sessions presented information on current research, invasion monitoring, early detection, rapid-response efforts, and operational management activities. Research summaries included invasion in Lake Ontario, prediction of invasion risk in Minnesota and Wisconsin using water chemistry data, and bulbil efficacy and distribution modeling in New England. In addition, the workshop offered summaries of attempted chemical and mechanical control tactics. Following presentations on previous studies, workshop participants identified research and management priorities. Critical research gaps identified from this workshop include (a) better understanding of the biology, invasion ecology, and management of starry stonewort; a greater understanding of distribution and movement, especially in the Great Lakes basin; enhanced population monitoring, applied research, and management strategies; and increased technical cooperation across government, academia, industry, and nonprofit organizations. Conclusions from this meeting will help prioritize future efforts focused on the adaptive management of starry stonewort in the United States and Canada.

Evaluating Soil Phosphorus Storage Capacity in Constructed Wetlands: Sampling and Analysis Protocol for Site Selection

Press Operations — Thu, 01 Oct 2020 12:23:19 GMT

Abstract: Soil characteristics determine the capacity of wetlands to sequester phosphorus (P). However, researchers have not yet developed a standard protocol for conducting soil sampling to document the soil phosphorus storage capacity (SPSC) for constructed wetland site selection. In response, the following technical note provides step-by-step instructions for selecting soil sample locations, describing site conditions, conducting soil sampling, and preparing samples for laboratory analysis. This note also includes calculations and interpretation of SPSC.

STE Environmental Manager (STEEM) Demonstration Web Application

Press Operations — Thu, 01 Oct 2020 12:17:57 GMT

Abstract: This report provides a summary of the development of the Synthetic Training Environment (STE) Environmental Manager (STEEM) demonstration web application. The purpose of this web application is twofold: (1) demonstrate a web application that enables non-technical users to prepare, run, and manage the physics-based models used by the STE to simulate realistic environmental conditions and (2) show how technologies developed by the Engineered Resilient Systems (ERS) Research and Development Area can be used to rapidly create applications to support U.S. Army Engineer Research and Development Center (ERDC) programs like the STE. A full build-out of STEEM would leverage the following ERS-developed technologies: data services, model development environment tools, model coupling/interface API, simulation workflow manager, and scenario generation tools.

A First Examination of the Interaction between Alternaria alternantherae and Agasicles hygrophila on Alternanthera philoxeroides

Press Operations — Tue, 29 Sep 2020 16:14:21 GMT

PURPOSE: The use of an alligatorweed (Alternanthera philoxeroides) insect biological control agent, alligatorweed flea beetle (Agasicles hygrophila Selman and Vogt), and the leaf spot plant pathogen, alligatorweed leaf pathogen (Alternaria alternantherae Holcomb and Antonopoulis), may provide enhanced control of alligatorweed infestations if competitive interactions between agents are minimal and damage to host plants are synergistic. However, to assess suitability of co-use of these two agents, it is necessary to first identify whether introduction of one may impact performance of the other. This technical note details a first examination of competitive interactions between A. hygrophila and A. alternantherae under varied temperature and host nutritional conditions. Presented are the results of laboratory experimentation and recommendations for future research.

Using Unmanned Aircraft System (UAS) and Satellite Imagery to Map Aquatic and Terrestrial Vegetation

Press Operations — Tue, 29 Sep 2020 15:39:51 GMT

Purpose: The purpose of this study is to demonstrate the application potential of using unmanned aerial systems (UAS) combined with a time series of moderately high-resolution satellite imagery for mapping ecological restoration progress and resulting land cover changes. This technical note addresses a project under the US Army Corps of Engineers Ecosystem Management and Restoration Research Project (EMRRP) focusing on image acquisition and assessment, digital image processing techniques, analytical methodology, geospatial product development, and documentation of best practice for future data acquisition and analysis in support of ecological management efforts.

PUBLICATION NOTICE: A Proposed Ecosystem Services Analysis Framework for the U.S. Army Corps of Engineers

Press Operations — Thu, 20 Aug 2020 14:51:10 GMT

Abstract: Ecosystem goods and services (EGS) have been promoted as a way to effectively examine tradeoffs and improve communication of project-related environmental outcomes in terms of human well-being. This document proposes a framework to inform the development of any future guidance to U.S. Army Corps of Engineers (USACE) District planners for projecting changes in EGS from proposed civil works activities. The framework offers an analytical and communications approach for incorporating EGS in USACE decision-support processes. The core of the framework is a conceptual model that establishes a series of causal relationships that link management actions to EGS benefits/damages, applying economic concepts in both monetary and non-monetary benefit relevant indicators. The six-step planning process is used to demonstrate how the EGS framework might be integrated into existing analytic approaches and modified to fit different levels of resource availability and decision contexts. A hypothetical case study is used to demonstrate analytic techniques. The framework is compatible with goals to create a single decision-support document covering National Environmental Policy Act requirements and planning objectives when comparing project alternatives. The example is intended to generally illustrate the use of EGS in any type of program planning or project evaluation.