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Jer-2021 assistance to the State Water Resources Research Institute Program (year 1 of 5) for the 104(b) program
No full textRESET Reengineering, System Engineering & Test Services
No full textSustainment of aging Department of Defense systems presents significant challenges. The Space Dynamics Laboratory (SDL) offers a cost-effective partnership to help the military maintain or enhance the capability of legacy systems. SDL provides trusted reengineering, system engineering, and test (RESET) services, providing Government-owned technical solutions that help the military
Bite by Bite: How Ungulate Browsing Shapes North America\u27s Forest Future
No full textUngulate browsing represents a contemporary issue for forest development, influencing forest regeneration, composition, and management practices across the world, especially in North America. This review synthesizes findings from 101 studies conducted between 1980 and 2025 to examine patterns of herbivory damage through browsing by moose, elk, white-tailed deer, black-tailed deer, and bison. Despite regional variation, high ungulate density consistently emerges as the primary factor driving browsing intensity and ecological and economic impact, leading to decreased social acceptance of coexistence with ungulates. This review highlights the selective suppression of palatable species such as balsam fir, red oak, and white cedar, leading to shifts toward less-preferred conifers. Preventive and control measures, ranging from fencing and repellents to regulated hunting, are widely implemented but vary in effectiveness and social acceptability. Although predator presence is an evident controlling factor, it was not statistically associated in this review with reduced browsing, nor with behavioral or trophic cascade effects. Ultimately, this study underscores the importance of integrated management strategies that combine silvicultural adaptation, population control, and, where feasible, predator reintroduction to ensure forest resilience and sustainability in the face of increasing pressure from climate change
Practical Effectiveness of Large Language Models in Assisting Landscape Architects in Plant Selection
No full textArtificial intelligence (AI) is rapidly transforming many industries, but its role in landscape architecture remains relatively unexplored. This study examines how AI, specifically GPT-4, can assist landscape architects in selecting plants for projects. By comparing AI-generated plant lists to those that human experts created, the research evaluates Accuracy, Suitability, Availability, Aesthetics, and Professional Usability. The results show that AI-generated plant lists were highly efficient, accurately matching site conditions and improving plant availability while significantly reducing selection time. However, human expertise was essential for ensuring aesthetic quality and design intent. While AI can serve as a powerful tool for streamlining plant selection, it is most effective when used alongside human judgment rather than as a replacement. These findings highlight AI’s potential to support landscape architects by automating research and expanding plant selection options. Future research should explore AI’s adaptability across different climates and its integration with plant databases to improve accuracy. By combining AI’s adaptability across different climates and its integration with plant databases, there is great potential to improve accuracy. By combining AI’s efficiency with human creativity, landscape architects can enhance the design process while maintaining ecological and aesthetic integrity
Energy Input–Output Meta-Analysis Reveals Algal Diesel Struggles to Break Even
No full textAlgal biofuels have been investigated as an alternative to fossil fuels and first-generation biofuels for transportation in the United States since the 1970s. Yet after five decades of development, scalability and implementation remain limited—largely due to persistent barriers such as low biomass productivity, modest lipid yields, and energy-intensive processing methods. These technical challenges significantly constrain the feasibility of large-scale commercialization despite substantial research and investment. To evaluate progress toward commercial viability, this study harmonized energy inputs and outputs across 508 observations on the production of algal biofuel energy return on energy investment (EROEI) in the United States. While bioethanol achieves an EROEI of (2.8) and oil (8.7), the analysis produced a mean EROEI of 1.01—essentially the break-even point—irrespective of system boundaries. Life-cycle analysis results showed that hydrothermal liquefaction in algal diesel production yielded a slightly higher mean EROEI (0.67) than transesterification (0.51), yet both showed net energy losses. Co-products were found to increase EROEI values, particularly when recycled into production processes. Collectively, these findings indicate that research and development to date has not produced a technology with net energy gains sufficient for commercial viability. For this reason, algal biofuels show little potential to alleviate the ongoing decline in the EROEI of petroleum and are not a promising renewable energy option for reducing greenhouse gas emissions from the transportation sector. They also show little promise for alleviating the land use, food vs. fuel and other controversies that have plagued first and second-generation biofuels
Simplification of Woody Plant Trait Networks Among Communities Along a Climatic Aridity Gradient
No full text1. Plant ecological strategies are shaped by numerous functional traits and their trade-offs. Trait network analysis enables testing hypotheses for the shifting of trait correlation architecture across communities differing in climate and productivity.
2. We built plant trait networks (PTNs) for 118 species within six communities across an aridity gradient, from forest to semi-desert across the California Floristic Province, based on 34 leaf and wood functional traits, representing hydraulic and photosynthetic function, structure, economics and size. We developed hypotheses for the association of PTN parameters with climate and ecosystem properties, based on theory for the adaptation of species to low resource/stressful environments versus higher resource availability environments with greater potential niche differentiation. Thus, we hypothesized that across community PTNs, trait network connectivity (i.e., the degree that traits are intercorrelated) and network complexity (i.e., the number of trait modules, and the degree of trait integration among modules) would be lower for communities adapted to arid climates and higher for communities adapted to greater water availability, similarly to trends expected for phylogenetic diversity, functional richness and productivity. Further, within given PTNs, we hypothesized that traits would vary strongly in their network connectivity and that the traits most centrally connected within PTNs would be those with the least across-species variation.
3. Across communities from more arid to wetter climates, PTN architecture varied from less to more interconnected and complex, in association with functional richness, but PTN architecture was independent of phylogenetic diversity and ecosystem productivity. Within the community PTNs, traits with lower species variation were more interconnected.
4. Synthesis. The responsiveness of PTN architecture to climate highlights how a wide range of traits contributes to physiological and ecological strategies with an architecture that varies among plant communities. Communities in more arid environments show a lower degree of phenotypic integration, consistent with lesser niche differentiation. Our study extends the usefulness of PTNs as an approach to quantify tradeoffs among multiple traits, providing connectivity and complexity parameters as tools that clarify plant environmental adaptation and patterns of trait associations that would influence species distributions, community assembly, and ecosystem resilience in response to climate change
Dataset: Compositional Analysis and Hydrothermal Liquefaction of a High-Ash Microalgae Biofilm
No full textThis dataset contains biochemical composition data and hydrothermal liquefaction (HTL) yield results for a high-ash microalgae biofilm which was cultivated in effluent from a mesophilic anaerobic digester using polyethylene rotating algae biofilm reactors (RABRs). These data were originally collected for use in a techno-economic analysis of biocrude, biodiesel, and bioplastic production from algae that was cultivated using RABRs for municipal wastewater reclamation.
Biochemical data for the microalgae biomass includes bulk protein, measured both using the Bradford protein assay and by multiplying total N; carbohydrate content, measured using a 3-methyl-2-benzothiazolinone hydrazone / dithiothreitol (MBTH/DTT) assay; total lipid content, measured using a sulpho-phospho-vanillin method; hexane-extractable lipid content, measured by mass difference after extraction with methanol and hexane; ash content, measured by mass difference after incineration at 550°C; moisture content of the harvested biofilm slurry, measured by mass difference after drying at 60°C, mineral composition, measured using an inductively-coupled plasma spectrophotometer; higher heating value, measured using a bomb calorimeter; and CHNS-O elemental composition, measured using an elemental analyser.
Data reported for the HTL product phases include mass yields for each phase (solid, aqueous, biocrude, gas); higher heating value of the biocrude phase, measured using a bomb calorimeter; elemental composition of the biocrude phase, measured using an elemental analyzer; and chemical properties of the aqueous phase, including pH, chemical oxygen demand (HACH method 8000), total nitrogen (HACH method 10,208), total ammonia (HACH method 10,301), total phosphorus (HACH method 10,209/10,210), and total organic carbon (HACH method 10,267).
Currently, the effects of ash composition and HTL heating rate on biocrude yields and on N and P partitioning into biocrude, aqueous, and solid phases are not clearly defined. Models used to predict biocrude yields after HTL of microalgae are commonly trained using data collected from numerous studies. This dataset contains the feedstock composition data and ramp rate data necessary to help define the effects of ash content on biocrude yields after HTL and can be reused to help train yield-prediction models for the HTL of microalgae and other feedstocks
James Buttle Review: Bed, Banks and Beyond: River Flood Dynamics
No full textFloods are amplified and attenuated by features and processes across spatial scales, defined here as flood dynamics. We review and synthesise these influences at the catchment, river network and reach scales as a means of integrating understanding of controls on flood dynamics and identifying key questions that arise because of differences in techniques of investigation and disciplinary emphases between spatial scales. Catchment-scale influences include catchment area, topography, lithology, land cover, precipitation, antecedent conditions and human alterations such as changing land cover. Network-scale influences on flood dynamics include network topology, longitudinal variations in the geometry of successive river corridor reaches, lakes and wetlands and human alterations including flow regulation and cumulative changes in channel-floodplain connectivity in multiple reaches across a network. Reach-scale influences on flood dynamics include water sources, river corridor geometry and connectivity and human alterations such as artificial levees, channelisation, bank stabilisation, changes to floodplain land cover and drainage, dike operation, process-based river restoration and urban stormwater management. Our review and synthesis of relevant literature suggest that the relative importance of these multiple influences on flood dynamics varies across spatial scales. Hillslope response may dominate hydrograph characteristics in smaller catchments, for example, whereas network geometry and flow dynamics exert progressively stronger influences on flood dynamics with increasing catchment size. Scale-specific advances in understanding flood dynamics, including rainfall-runoff analyses of water movements from uplands into channel networks (catchment-scale), analyses of flow dynamics along networks of multiple channel reaches (network-scale) and investigations of biophysical feedbacks and the influences of river corridor geometry and hydraulic roughness (reach-scale), have largely contributed to understanding flood dynamics, but there remain important disconnects between these diverse bodies of research and outstanding questions related to the cumulative effects on flood dynamics across scales
The Continuing Search for a Better Mouse Trap: Two Tests of a Practical, Low-Cost Camera Trap for Detecting and Observing Small Mammals
No full textThe advent of digital wildlife cameras has led to a dramatic increase in the use of camera traps for mammalian biodiversity surveys, ecological studies and occupancy analyses. For cryptic mammals such as mice and shrews, whose small sizes pose many challenges for unconstrained digital photography, use of camera traps remains relatively infrequent. Here we use a practical, low-cost small mammal camera platform (the “MouseCam”) that is easy and inexpensive to fabricate and deploy and requires little maintenance beyond camera service. We tested the MouseCam in two applications: a study of small mammal species composition on two transects across a barrier island and a study of small mammal occupancy along a subtle elevation gradient in a mainland forest. The MouseCam was reasonably efficient, with over 78% of all images containing a recognizable small mammal (mouse, vole, rat or shrew). We obtained an accurate estimate of species composition on the island transects, as indicated by comparison with both concurrent and long-term trapping records for the same transects. MouseCams required a smaller expenditure of personnel and transportation resources than would be required for live trapping. They also detected subtle elevation-related differences in species occupancy in the mainland forest for the marsh rice rat, with the species occurring at lower elevations in the forest. This is consistent with the typical occurrence of the marsh rice rat in marshes and wetlands. We also tested devices (barriers, runways) designed to reduce disturbance by mesopredators (e.g., raccoons). Adding an internal barrier to the MouseCam did not reduce use by white-footed mice, whereas adding an external runway did. We believe specialized small mammal camera-based sensors may have wide applicability in field studies of small mammal distribution, abundance and biology