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Sego SupremeTM is a designated plant breeding and introduction program at the Utah State University Botanical Center and the Center for Water Efficient Landscaping. This plant selection program introduces native and adapted plants to the arid West for aesthetic landscaping and water conservation. The plants are evaluated for characteristics such as color, flowering, ease of propagation, market demand, disease/pest resistance, and drought tolerance. However, salt tolerance has not been considered during the evaluation processes. Four Sego SupremeTM plants [Aquilegia barnebyi (oil shale columbine), Clematis fruticosa (Mongolian gold clematis), Epilobium septentrionale (northern willowherb), and Tetraneuris acaulis var. arizonica (Arizona four-nerve daisy)] were evaluated for salt tolerance in a greenhouse. Uniform plants were irrigated weekly with a nutrient solution at an electrical conductivity (EC) of 1.25 dS·m−1 as control or a saline solution at an EC of 2.5, 5.0, 7.5, or 10.0 dS·m−1 for 8 weeks. After 8 weeks of irrigation, A. barnebyi irrigated with saline solution at an EC of 5.0 dS·m−1 had slight foliar salt damage with an average visual score of 3.7 (0 = dead; 5 = excellent), and more than 50% of the plants were dead when irrigated with saline solutions at an EC of 7.5 and 10.0 dS·m−1. However, C. fruticosa, E. septentrionale, and T. acaulis had no or minimal foliar salt damage with visual scores of 4.2, 4.1, and 4.3, respectively, when irrigated with saline solution at an EC of 10.0 dS·m−1. As the salinity levels of treatment solutions increased, plant height, leaf area, and shoot dry weight of C. fruticosa and T. acaulis decreased linearly; plant height of A. barnebyi and E. septentrionale also declined linearly, but their leaf area and shoot dry weight decreased quadratically. Compared with the control, the shoot dry weights of A. barnebyi, C. fruticosa, E. septentrionale, and T. acaulis decreased by 71.3%, 56.3%, 69.7%, and 48.1%, respectively, when irrigated with saline solution at an EC of 10.0 dS·m−1. Aquilegia barnebyi and C. fruticosa did not bloom during the experiment at all treatments. Elevated salinity reduced the number of flowers in E. septentrionale and T. acaulis. Elevated salinity also reduced the number of shoots in all four species. Among the four species, sodium (Na+) and chloride (Cl–) concentration increased the most in A. barnebyi by 53 and 48 times, respectively, when irrigated with saline solution at an EC of 10.0 dS·m−1. In this study, C. fruticosa and T. acaulis had minimal foliar salt damage and less reduction in shoot dry weight, indicating that they are more tolerant to salinity. Epilobium septentrionale was moderately tolerant to saline solution irrigation with less foliar damage, although it had more reduction in shoot dry weight. On the other hand, A. barnebyi was the least tolerant with severe foliar damage, more reduction in shoot dry weight, and a greater concentration of Na+ and Cl–.

The pressure to develop new and renewable forms of energy to combat climate change, ocean acidification, and energy security has encouraged exploration of sources of power generation from the ocean. One of the major challenges to deploying these devices is discerning the likely effects those devices and associated systems will have on the marine environment. Determining the effects each device design and deployment system may have on specific marine animals and habitats, estimating the extent of those effects upon the resiliency of the ecosystem, and designing appropriate mitigation measures to protect against degradation all pose substantial challenges. With little direct observational or experimental data available on the effects of wave, tidal, and offshore wind devices on marine animals, habitats, and ecosystem processes, researchers have developed the Environmental Risk Evaluation System (ERES) to provide preliminary assessments of these risks and to act as a framework for integrating future data on direct interactions of ocean energy devices with the environment. Using biophysical risk factors, interactions of marine animals and seabirds, with ocean energy devices and systems, are examined; potential effects on habitats, and changes in processes such as sedimentation patterns and water quality, are also considered. The risks associated with specific interactions for which data are more readily available are explored including interactions between ocean energy devices and surface vessels, toxicity of anti-biofouling paints, and potential for harm to animals from turbine blade strike. ERES also examines the effect that environmental regulations have on the deployment and operation of ocean energy devices.

Water conservation efforts in urban landscapes have increased the need for water-wise-plants. A potential source includes multiple native, drought-adapted species. A lack of researched propagation protocols makes commercial production of many species difficult. We examined germination of three native plant species (Purshia stansburiana, Cercocarpus ledifolius, and Forestiera pubescens) in three substrates. Both P. stansburiana and C. ledifolius are endemic to semiarid areas. Forestiera pubescens is found in riparian areas but is drought hardy once established. Stratified seed of each were sown in substrates varying in organic matter (OM) content and water-holding porosity (WHP) characteristics: (1) a commercial germination mix (83% OM); (2) a self-blended combination of a commercial potting soil mixed volumetrically 1:1 with vermiculite (37% OM); and (3) a calcined clay (0% OM). Germination was monitored for 60 days. Percent germination was highest in the calcined clay for each species evaluated (P. stansburiana: 63%, C. ledifolius: 51% and F. pubescens: 83%). These rates were at least 25% greater than the next best medium, the self-blended substrate. The commercial germination blend was the least favorable for germination. These results suggest that the common commercial practice of using germination substrates may not be suited to germinating many species native to arid areas.

An integrated modeling approach is used to link land use to river discharge, and then to survival of larval walleye that hatch in northern Ohio streams draining into Lake Erie (USA). First, to link land use and river discharge, the parameters of a simple hydrologic model are statistically related to watershed landscape attributes, including forest cover. One such relationship allows estimation of the change in daily river discharge that could result from a reduction in basin-scale forest cover. Second, to represent the river discharge-larval survival link, we reexamine a dataset from Mion and others to propose a relationship between daily flow velocity, water temperature, and walleye larval survival. Together, these linked models provide estimates of the reduction in larval survival due to reduction in forest cover, along with the uncertainty of those estimates. For the Grand River watershed, decreasing forest cover from 45.2 to 30% is projected to reduce average larval survival by about 45%. In the adjacent Chagrin River, dropping cover from 62.5 to 30% reduces survival by almost 60%. The greater rate of reduction of survival in the Chagrin River as forest levels fall is explained by a relatively greater increase in storm flows for the Chagrin, due to more frequently saturated soils. Therefore, forest preservation in the Chagrin River watershed is projected to be more effective in preserving walleye larval tributary habitat.

There are a variety of sensor systems deployed at border crossings and ports of entry throughout the world that scan for illicit nuclear material. These systems employ detection algorithms that interpret the output of the scans and determine whether additional investigation is warranted. In this work, we demonstrate an approach for comparing the performance of such detection algorithms. We optimize each algorithm by minimizing risk, which considers the probability distribution of threat sources and the consequence of detection errors. Our method is flexible and is easily adapted to many different assumptions regarding the probability of a conveyance containing illicit material and the relative consequences of false positive and false negative errors. This approach can help developers and decision makers identify optimal settings for these algorithms. We illustrate the method by comparing the risk from two families of detection algorithms and discuss the generalizability of the method.

Films of Co0.85Zn0.15Fe2O4 nanoparticles were prepared on silanized glass substrates using aminobenzoic acid/imidazole-modified magnetic nanoparticles. Dispersive Faraday rotations in the nanoparticulate films were observed as 1.0°–3.0° under relatively low applied magnetic field strengths of less than 500 Oe. The magnitude of the Faraday rotation increases with increasing thickness of the prepared films. No differences in the Faraday rotation were observed for Co0.85Zn0.15Fe2O4 nanoparticles as the particle size varied from 12 to 18 nm.

We demonstrate an approach for assessing the quality of a signature system designed to predict the culture medium used to grow a microorganism. The system was comprised of four chemical assays designed to identify various ingredients that could be used to produce the culture medium. The analytical measurements resulting from any combination of these four assays can be used in a Bayesian network to predict the probabilities that the microorganism was grown using one of eleven culture media. We evaluated combinations of the signature system by removing one or more of the assays from the Bayes network. We measured and compared the quality of the various Bayes nets in terms of fidelity, cost, risk, and utility, a method we refer to as Signature Quality Metrics

This white paper accompanies a demonstration model that implements methods for the risk-informed design of monitoring, verification and accounting (RI-MVA) systems in geologic carbon sequestration projects. The intent is that this model will ultimately be integrated with, or interfaced with, the National Risk Assessment Partnership (NRAP) integrated assessment model (IAM). The RI-MVA methods described here apply optimization techniques in the analytical environment of NRAP risk profiles to allow systematic identification and comparison of the risk and cost attributes of MVA design options.

Possible environmental effects of marine and hydrokinetic (MHK) energy development are not well understood, and yet regulatory agencies are required to make decisions in spite of substantial uncertainty about environmental impacts and their long-term effects. An understanding of risk associated with likely interactions between MHK installations and aquatic receptors, including animals, habitats, and ecosystems, can help reduce the level of uncertainty and focus regulatory actions and scientific studies on interactions of most concern. As a first step in developing the Pacific Northwest National Laboratory (PNNL) Environmental Risk Evaluation System (ERES), PNNL scientists conducted a preliminary risk screening analysis on three initial MHK cases - a tidal project in Puget Sound using Open Hydro turbines, a wave project off the coast of Oregon using Ocean Power Technologies point attenuator buoys, and a riverine current project in the Mississippi River using Free Flow turbines. Through an iterative process, the screening analysis revealed that top-tier stressors in all three cases were the effects of the dynamic physical presence of the device (e.g., strike), accidents, and effects of the static physical presence of the device (e.g., habitat alteration). Receptor interactions with these stressors at the four highest tiers of risk were dominated by marine mammals (cetaceans and pinnipeds) and birds (diving and non-diving); only the riverine case (Free Flow) included different receptors in the third tier (fish) and the fourth tier (benthic invertebrates). Although this screening analysis provides a preliminary analysis of vulnerability of environmental receptors to stressors associated with MHK installations, probability analysis, especially of risk associated with chemical toxicity and accidents such as oil spills or lost gear, will be necessary to further understand high-priority risks. Subject matter expert review of this process and results is required and is planned for the first quarter of FY11. Once expert review is finalized, the screening analysis phase of ERES will be complete.

The Environmental Risk Evaluation System (ERES) has been created to set priorities among the environmental risks from offshore wind development. This report follows the conceptual design for ERES and shows what the system would look like, using a web interface created as part of a Knowledge Management System (KMS) for offshore wind. The KMS, called Zephyrus, and ERES for offshore wind, will be populated and made operational in a later phase of the project.

The production of electricity from the moving waters of the ocean has the potential to be a viable addition to the portfolio of renewable energy sources worldwide. The marine and hydrokinetic (MHK) industry faces many hurdles, including technology development, challenges of offshore deployments, and financing; however, the barrier most commonly identified by industry, regulators, and stakeholders is the uncertainty surrounding potential environmental effects of devices placed in the water and the permitting processes associated with real or potential impacts.

In this report we describe the development of the Environmental Risk Evaluation System (ERES), a risk-informed analytical process for estimating the environmental risks associated with the construction and operation of marine and hydrokinetic energy generation projects. The development process consists of two main phases of analysis. In the first phase, preliminary risk analyses will take the form of screening studies in which key environmental impacts and the uncertainties that create risk are identified, leading to a better-focused characterization of the relevant environmental effects. Existence of critical data gaps will suggest areas in which specific modeling and/or data collection activities should take place. In the second phase, more detailed quantitative risk analyses will be conducted, with residual uncertainties providing the basis for recommending risk mitigation and monitoring activities. We also describe the process used for selecting three cases for fiscal year 2010 risk screening analysis using the ERES. A case is defined as a specific technology deployed in a particular location involving certain environmental receptors specific to that location. The three cases selected satisfy a number of desirable criteria: 1) they correspond to real projects whose deployment is likely to take place in the foreseeable future; 2) the technology developers aremore » willing to share technology and project-related data; 3) the projects represent a diversity of technology-site-receptor characteristics; 4) the projects are of national interest, and 5) environmental effects data may be available for the projects.« less

In this report we describe the development of the Environmental Risk Evaluation System (ERES), a risk-informed analytical process for estimating the environmental risks associated with the construction and operation of offshore wind energy generation projects. The development of ERES for offshore wind is closely allied to a concurrent process undertaken to examine environmental effects of marine and hydrokinetic (MHK) energy generation, although specific risk-relevant attributes will differ between the MHK and offshore wind domains. During FY10, a conceptual design of ERES for offshore wind will be developed. The offshore wind ERES mockup described in this report will provide a preview of the functionality of a fully developed risk evaluation system that will use risk assessment techniques to determine priority stressors on aquatic organisms and environments from specific technology aspects, identify key uncertainties underlying high-risk issues, compile a wide-range of data types in an innovative and flexible data organizing scheme, and inform planning and decision processes with a transparent and technically robust decision-support tool. A fully functional version of ERES for offshore wind will be developed in a subsequent phase of the project.

Malaria and other vector-borne diseases represent a significant and growing burden in many tropical countries. Successfully addressing these threats will require policies that expand access to and use of existing control methods, such as insecticide-treated bed nets (ITNs) and artemesinin combination therapies (ACTs) for malaria, while weighing the costs and benefits of alternative approaches over time. This paper argues that decision analysis provides a valuable framework for formulating such policies and combating the emergence and re-emergence of malaria and other diseases. We outline five challenges that policy makers and practitioners face in the struggle against malaria, and demonstrate how decision analysis can help to address and overcome these challenges. A prototype decision analysis framework for malaria control in Tanzania is presented, highlighting the key components that a decision support tool should include. Developing and applying such a framework can promote stronger and more effective linkages between research and policy, ultimately helping to reduce the burden of malaria and other vector-borne diseases.

A technique was developed to estimate the R-curve behavior of Y-TZP using indentation-produced flaws. This technique allows crack-growth resistance to be determined for short crack extensions (micrometers). For Y-TZP samples sintered at 1600°C for 1 h (mean grain size, 0.7 μm), the crackgrowth resistance increases rapidly over the first 10 μm. Peak toughness values determined from this technique correlate with chevron-notch fracture toughness if the ellipticity of the indentation-produced flaw is considered.

Over-the-horizon (OTH) radar uses the refractive properties of high-frequency radiowave propagation through the ionosphere for wide-area surveillance at long ranges. Ionospheric propagation often gives rise to multiple raymodes between the OTH radar and a target which results in multiple slant tracks from a single target. Multipath and multiple target ambiguities are typically resolved by assuming that the down-range ionosphere is known precisely and then using ray tracing to determine the coordinate registration (CR) transformations from slant coordinates to target locations in ground coordinates. To achieve greater robustness to the uncertainty in down-range ionospheric conditions, this paper presents a maximum a posteriori (MAP) mode linking method for track association that employs statistical modeling of the down-range plasma frequency profile and corresponding multipath slant track measurements. To determine the statistical model parameters from quasi-vertical incidence (QVI) ionogram and wide-sweep backscatter ionogram (WSBI) measurements, the plasma frequency profile is approximated as a homogeneous random process over the region near the mid-point between the radar and the dwell illumination region. Using samples of a 3-D ionospheric model fitted to the and QVIs and WSBIs, statistical propagation model parameters are obtained by smoothed bootstrap resampling combined with Monte Carlo evaluation of a ray tracing propagation model. Simulation results indicate that the MAP mode linking method can achieve nearly a 3:1 improvement in ground coordinate accuracy over conventional mode linking methods with much higher probabilities of correct raymode identification and slant-track-to-target assignment. Real data results from roughly 90 minutes of OTH radar slant track data demonstrate that the MAP mode linking method can provide as much as a 4:1 improvement in ground coordinate accuracy over conventional methods.

This paper addresses the problem of estimating range-varying parameters of the height-dependent index of refraction over the sea surface in order to predict ducted microwave propagation loss. Refractivity estimation is performed using a Markov model for microwave radar clutter returns from the sea surface. Specifically, the parabolic approximation for numerical solution of the wave equation is used to formulate the problem within a non-linear recursive Bayesian state estimation framework. Solution for the maximum a posteriori (MAP) sequence of range-varying refractivity parameters, given log-amplitude clutter versus range data, is achieved using a technique based on the Viterbi algorithm. Simulation and real data results based on experiments performed off Wallops Island, Virginia are presented which quantify the technique's ability to predict propagation loss at 3 GHz.

This paper addresses the problem of predicting microwave propagation loss under ducting conditions by means of estimating the range and height varying index of refraction from observations of radar sea clutter returns. Specifically, the Fourier split-step solution to the parabolic equation for wave propagation is used to formulate the problem into a non-linear dynamic state-estimation framework. Solution for the maximum a posteriori (MAP) sequence estimate of the range-varying refractivity is achieved by extending notions of particle filtering framework to the Viterbi algorithm for state estimation. Real data results based on experiments performed off Wallops Island, Virginia are presented which quantify the proposed methods ability to predict propagation loss at 3 GHz.

An approach for the analysis and management of multiple criteria critical infrastructure problems is put forth. Nuclear waste management involves complex tradeoffs under uncertainty. Among all waste either generated by nature or human activities, radioactive nuclear waste is the most toxic to human health and difficult to manage: it is known that some nuclear waste material will be radioactive and potentially dangerous for hundreds of thousands of years. This paper discusses the use of multiple criteria decision analysis techniques such as the analytic hierarchy process for recommending sites to be considered as potential repositories for nuclear waste.

The thermal conductivity and specific heat of mullite-cordierite composites have been measured in the temperature range 90 K to 420 K. The sound velocity, as determined from a fit to the specific heat data, agrees well with velocities determined from mechanical measurements. The temperature and composition dependence of the phonon mean free path is established. The thermal conductivity as a function of composition passes through a minimum for the mullite-rich compositions due to a minimum in the upper limit of the phonon mean free path. Solid solution formation is a possible cause.