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At least 1,081 records · Page 60Linked to original sources
USGS2020

Towards a U.S. national program for monitoring native bees

North America has more than 4000 bee species, yet we have little information on the health, distribution, and population trends of most of these species. In the United States, what information is available is distributed across multiple institutions, and efforts to track bee populations are largely uncoordinated on a national scale. An overarching framework for monitoring U.S. native bees could provide a system that is responsive to national needs, resources, and capacities. Five major action areas and priorities for structuring a coordinated effort include: (1) Defining the scope, aims, and cost of a national native bee monitoring program; (2) Improving the national capacity in bee taxonomy and systematics; (3) Gathering and cataloging data that are standardized, accessible, and sustainable; (4) Identifying survey methods and prioritizing taxa to monitor; and (5) Prioritizing geographic areas to be monitored. Here, we detail the needs, challenges, and opportunities associated with developing a multi-layered U.S. national plan for native bee monitoring.

Biological Conservation↗
USGS2021

Genetic diversity is considered important but interpreted narrowly in country reports to the Convention on Biological Diversity: Current actions and indicators are insufficient

International agreements such as the Convention on Biological Diversity (CBD) have committed to conserve, and sustainably and equitably use, biodiversity. The CBD is a vital instrument for global conservation because it guides 195 countries and the European Union in setting priorities and allocating resources, and requires regular reporting on progress. However, the CBD and similar policy agreements have often neglected genetic diversity. This is a critical gap because genetic diversity underlies adaptation to environmental change and ecosystem resilience. Here we aim to inform future policy, monitoring, and reporting efforts focused on limiting biodiversity loss by conducting the largest yet evaluation of how Parties to the CBD report on genetic diversity. A large, globally representative sample of 114 CBD National Reports was examined to assess reported actions, progress, values and indicators related to genetic diversity. Although the importance of genetic diversity is recognized by most Parties to the CBD, genetic diversity targets mainly addressed variation within crops and livestock (a small fraction of all species). Reported actions to conserve genetic diversity primarily concerned ex situ facilities and legislation, rather than monitoring and in situ intervention. The most commonly reported status indicators are not well correlated to maintaining genetic diversity. Lastly, few reports mentioned genetic monitoring using DNA data, indigenous use and knowledge of genetic diversity, or development of strategies to conserve genetic diversity. We make several recommendations for the post-2020 CBD Biodiversity Framework, and similar efforts such as IPBES, to improve awareness, assessment, and monitoring of genetic diversity, and facilitate consistent and complete reporting in the future.

Biological Conservation↗
USGS2023

Scenario-Based Decision Analysis: Integrated scenario planning and structured decision making for resource management under climate change

Managing resources under climate change is a high-stakes and daunting task, especially because climate change and associated complex biophysical responses engender sustained directional changes as well as abrupt transformations. This environmental non-stationarity challenges assumptions and expectations among scientists, managers, rights holders, and stakeholders. These challenges are anything but straightforward – a high degree of uncertainty impedes our ability to predict the environmental trajectory with confidence, and affected resources often span multiple governance jurisdictions or are subject to competing management objectives. Fortunately, tools exist to help grapple with such challenges. Two commonly used tools are scenario planning (SP) and structured decision making (SDM). SP is a well-established approach for assessing system response and facilitating decision making under a wide range of conditions that are uncertain and uncontrollable, such as those associated with adapting to climate change. However, SP lacks a defined structure for establishing objectives, quantifying tradeoffs, and evaluating the performance of candidate decisions to meet those objectives. SDM, on the other hand, is rooted in decision theory and focuses on explicit (often quantitative) assessment of the expected outcomes of choosing among a set of decision alternatives. SDM has been criticized for an inability to account for surprises and for imposing an overly narrow framing of problems to increase tractability. We discuss the strengths and limitations of SDM and SP as experienced through their application in various resource-management contexts, and then propose a new generalized framework – Scenario-Based Decision Analysis (SBDA) – that integrates these complementary approaches. SBDA structures resource management problems and solutions while considering uncertainties and surprises to inform resource management decision making.

Biological Conservation↗
USGS2024

Disentangling drivers of annual grass invasion: Abiotic susceptibility vs. fire-induced conversion to cheatgrass dominance in the sagebrush biome

Invasive annual grasses are often facilitated by fire, yet they can become ecologically dominant in susceptible locations even in the absence of fire. We used an extensive vegetation plot database to model susceptibility to the invasive annual grass cheatgrass ( Bromus tectorum L.) in the sagebrush biome as a function of climate and soil water availability variables. We built random forest models predicting cheatgrass presence or dominance (greater than 15 % relative cover) under unburned (37,219 plots) and burned conditions (6340 plots). We mapped predicted probability of cheatgrass presence and dominance, conditional on burning. We combined predicted susceptibility with burn probability to quantify the 10-year total risk of cheatgrass dominance. Finally, we identified portions of the landscape (1) at risk of fire-induced conversion to cheatgrass dominance, (2) consistently susceptible to cheatgrass dominance, or (3) consistently resistant to cheatgrass dominance. At the scale of the sagebrush biome, we found that abiotic susceptibility to cheatgrass dominance drives total risk, regardless of fire. At local scales (i.e., individual 30 m pixels), burning increased the probability of cheatgrass dominance by a median of 14 %. Threshold-based analyses indicate that 10–31 % of the sagebrush biome was at risk of fire-induced dominance, with 55 % exhibiting abiotic resistance and 5 % exhibiting abiotic susceptibility to dominance regardless of fire. Burn probability was higher in areas predicted to be susceptible to dominance, illustrating how cheatgrass invasion can cause ecosystem conversions that are then sustained by grass-fire cycles. Disentangling the influence of abiotic conditions and fire contributes to our understanding of the mechanisms driving invasion dynamics, and modeling the probability of dominance can help anticipate where ecological transformations are at risk of occurring. Our approach can facilitate the prioritization of management actions in the sagebrush biome and be used as a framework for modeling invasion risk in other disturbance-prone ecosystems.

Biological Conservation↗
USGS2025

Climate and land use drivers of freshwater fish biodiversity in the northeastern United States

Freshwater habitats can sustain high biodiversity, but habitat degradation, species invasion, and overexploitation have imperiled freshwater species. The multiple threats to freshwater habitats and changing stream characteristics due to climate change make it challenging to identify the drivers of fish vulnerability, especially given that the importance of drivers may vary by the biodiversity endpoint. The goals of this study were to 1) describe freshwater (lotic) fish biodiversity across northeastern states in the United States, and 2) identify geographic, climate, and land use drivers of fish biodiversity, toward improving freshwater fish conservation. We predicted habitat suitability for 53 fish species using survey data and corresponding geographic, climate, and land use data. After model fitting, we grouped species using a traditional approach based on traits and a new approach using modeled streamflow and stream temperature to create clusters. We found that climate and land use vulnerable groups did not always have similar geographic patterns or relationships to the climate or land use variables, suggesting that biota vulnerable to changing conditions may be overlooked by reliance on predefined guilds to set conservation goals. Biodiversity groups that were vulnerable to climate variables were also related to land use variables that can be used to identify restoration opportunities. This approach may be useful for managers interested in holistic freshwater management under changing stream conditions.

Connecticut, Maine, Massachusetts, New Hampshire, ↗
USGS2026

Long lives, short futures: Freshwater turtle and tortoise imports to the United States highlight global trade and conservation challenges

Global trade of freshwater turtles and tortoises presents substantial conservation, biosecurity, and regulatory challenges, particularly for long-lived species that are already highly imperiled. While the United States has historically played a key role in supplying the international chelonian trade, investigations into its role as an importer remain limited. We used import data from the U.S. Fish and Wildlife Service Law Enforcement Management Information System (LEMIS) between 2000 and 2022 to evaluate the trade of freshwater turtles and tortoises. Over 2.5 million individuals were imported into the United States during this period, comprising 172 species that are likely imported for the pet trade, food, and traditional medicine markets. Reported annual imports for freshwater turtles increased until approximately 2013 and decreased thereafter, whereas reported annual imports for tortoises have remained relatively constant. Two species, Chinese softshell turtles ( Pelodiscus sinensis ) and Horsfield's tortoises ( Testudo horsfieldii ) represent 62.9% of all imports. Imported species were largely classified as Vulnerable, Endangered, or Critically Endangered by the IUCN Red List, yet the conservation status of a concerning number of species ( n = 45; 26.2%) has not been evaluated. Many imports appear to be sourced from wild populations (28.3% of freshwater turtles, 71.3% of tortoises); however, captive-sourced imports increased significantly over time across both groups. Import volumes raise concerns regarding the sustainability of freshwater turtle and tortoise trade, the potential for invasive species establishment, and disease spread. Our results highlight the need for updated IUCN assessments, verification of trade records, and strengthening of biosecurity screening at U.S. ports of entry.

Biological Conservation↗
USGS2026

Biome-scale spatial patterns of avian abundance reveal proactive conservation opportunities in North American grasslands

North American grassland birds have experienced steeper population declines than any other avian guild, yet conservation efforts remain largely reactive and fragmented. We used nearly four decades of North American Breeding Bird Survey data to identify biome-scale spatial patterns (clustering) of grassland bird abundance for the Great Plains. Our results reveal an ecological core in the north-central Plains where community-level abundance is either increasing by >100% or remains high and stable, providing a strategic roadmap for a “Defend the Core” conservation approach. This approach flips the script from reactive triage centered on isolated population fragments to a proactive strategy of maintaining large-scale ecosystem integrity. Conversely, we found that population losses are more spatially clustered than wins, reflecting the relentless, one-way movement of woody encroachment and agricultural conversion. This asymmetry supports prioritizing intact landscapes, as current restoration rates are often outpaced by the scale of habitat loss. Notably, we found that community-level spatial clustering is a more robust indicator of biome condition than trends of individual flagship species, suggesting that managing for ecosystem integrity provides a more effective multi-species umbrella. Given our results, there is an opportunity for operationalizing a Great Plains Conservation Design that is ecosystem-centric and rooted in the sustainability of the private-land cattle production that maintains these open spaces. By leveraging avian abundance as a biological sensor, managers and producers can deploy a shared vision that matches the spatial scale of the threats, moving from reactive triage to proactive defense of core working grasslands in North America.

Great Plains biome↗
USGS2012

Impacts of biofuels production alternatives on water quantity and quality in the Iowa River Basin

Corn stover as well as perennial grasses like switchgrass (Panicum virgatum) and miscanthus are being considered as candidates for the second generation biofuel feedstocks. However, the challenges to biofuel development are its effects on the environment, especially water quality. This study evaluates the long-term impacts of biofuel production alternatives (e.g., elevated corn stover removal rates and the potential land cover change) on an ecosystem with a focus on biomass production, soil erosion, water quantity and quality, and soil nitrate nitrogen concentration at the watershed scale. The Soil and Water Assessment Tool (SWAT) was modified for setting land cover change scenarios and applied to the Iowa River Basin (a tributary of the Upper Mississippi River Basin). Results show that biomass production can be sustained with an increased stover removal rate as long as the crop demand for nutrients is met with appropriate fertilization. Although a drastic increase (4.7–70.6%) in sediment yield due to erosion and a slight decrease (1.2–3.2%) in water yield were estimated with the stover removal rate ranging between 40% and 100%, the nitrate nitrogen load declined about 6–10.1%. In comparison to growing corn, growing either switchgrass or miscanthus can reduce sediment erosion greatly. However, land cover changes from native grass to switchgrass or miscanthus would lead to a decrease in water yield and an increase in nitrate nitrogen load. In contrast to growing switchgrass, growing miscanthus is more productive in generating biomass, but its higher water demand may reduce water availability in the study area.

Iowa;Minnesota↗
USGS2019

Ecological effects of establishing a 40-year oasis protection system in a Northwestern China Desert

Aims: Desertification around oasis areas is a serious problem in semi-arid and arid regions, which is expected to continue into the future due to a rapidly increasing human population. Oasis protection systems are created to reverse desertification by recovering degraded soil and vegetation properties and improving ecosystem services. Most research has focused on the short-term effects of a single restoration practice using an individual vegetation or soil metric, while more complete assessments along a gradient of an entire oasis protection system have seldom been studied. In this study, soil and vegetation properties were measured along a 40-year oasis-protection system to assess the effectiveness of increasing land protection belts along a gradient from prohibiting grazing, to fencing shrubland, to establishing shrub- and tree-plantations in northwestern China. Methods: Three sites in each belt of the oasis-protection system were selected to measure soil texture, soil organic carbon, total nitrogen, total phosphorus, pH, electrical conductivity, and eight ions under the plant canopy and in the inter-canopy area, as well as to investigate plant community composition, diversity and productivity. Wind velocity and sand transportation rates were measured in each of the five belts during storm events. Results: Compared with shifting dunes in unprotected desert settings, the wind velocity and sand transportation rate decreased by 75 and 98%, respectively, when spring storms passed through the most protected plantation belts in the oasis system. Soil organic carbon, total nitrogen, total phosphorus significantly increased, along with the silt and clay contents, across the protection gradient, and reached their highest levels at the shrub- and tree-plantation belts. Similarly, the density, cover, and biomass of herbaceous plants also increased along the gradient. Despite these positive effects, there was a significant increase in soil salinity, sodicity, and desiccation at the shrub- and tree-plantation belts, which may negatively affect the future sustainability of the oasis-protection system under a predicted future drier and warming climate. Conclusions Although shrub and tree plantations improve soil fertility and favor the development of the herbaceous plant community, their environmental consequences (i.e., soil salinization and desiccation) need to be evaluated in the context of ecosystem restoration over the long-term, especially in arid regions.

Catena↗
USGS2005

Secondary sulfate minerals associated with acid drainage in the eastern US: Recycling of metals and acidity in surficial environments

Weathering of metal-sulfide minerals produces suites of variably soluble efflorescent sulfate salts at a number of localities in the eastern United States. The salts, which are present on mine wastes, tailings piles, and outcrops, include minerals that incorporate heavy metals in solid solution, primarily the highly soluble members of the melanterite, rozenite, epsomite, halotrichite, and copiapite groups. The minerals were identified by a combination of powder X-ray diffraction (XRD), scanning electron microscopy (SEM), and electron-microprobe. Base-metal salts are rare at these localities, and Cu, Zn, and Co are commonly sequestered as solid solutions within Fe- and Fe-Al sulfate minerals. Salt dissolution affects the surface-water chemistry at abandoned mines that exploited the massive sulfide deposits in the Vermont copper belt, the Mineral district of central Virginia, the Copper Basin (Ducktown) mining district of Tennessee, and where sulfide-bearing metamorphic rocks undisturbed by mining are exposed in Great Smoky Mountains National Park in North Carolina and Tennessee. Dissolution experiments on composite salt samples from three minesites and two outcrops of metamorphic rock showed that, in all cases, the pH of the leachates rapidly declined from 6.9 to <3.7, and specific conductance increased gradually over 24 h. Leachates analyzed after 24-h dissolution experiments indicated that all of the salts provided ready sources of dissolved Al (>30 mg L-1), Fe (>47 mg L-1), sulfate (>1000 mg L-1), and base metals (>1000 mg L-1 for minesites, and 2 mg L-1 for other sites). Geochemical modeling of surface waters, mine-waste leachates, and salt leachates using PHREEQC software predicted saturation in the observed ochre minerals, but significant concentration by evaporation would be needed to reach saturation in most of the sulfate salts. Periodic surface-water monitoring at Vermont minesites indicated peak annual metal loads during spring runoff. At the Virginia site, where no winter-long snowpack develops, metal loads were highest during summer months when salts were dissolved periodically by rainstorms following sustained evaporation during dry spells. Despite the relatively humid climate of the eastern United States, where precipitation typically exceeds evaporation, salts form intermittently in open areas, persist in protected areas when temperature and relative humidity are appropriate, and contribute to metal loadings and acidity in surface waters upon dissolution, thereby causing short-term perturbations in water quality.

Chemical Geology↗
USGS2021

The triple argon isotope composition of groundwater on ten-thousand-year timescales

Understanding the age and movement of groundwater is important for predicting the vulnerability of wells to contamination, constraining flow models that inform sustainable groundwater management, and interpreting geochemical signals that reflect past climate. Due to both the ubiquity of groundwater with order ten-thousand-year residence times and its importance for climate reconstruction of the last glacial period, there is a strong need for improving geochemical dating tools on this timescale. Whereas 14 C of dissolved inorganic carbon and dissolved 4 He are common age tracers for Late Pleistocene groundwater, each is limited by systematic uncertainties related to aquifer composition and lithology, and the extent of water-rock interaction. In principle, radiogenic 40 Ar in groundwater acquired from decay of 40 K in aquifer minerals should be insensitive to some processes that impact 14 C and 4 He and thus represent a useful, complementary age tracer. In practice, however, detection of significant radiogenic 40 Ar signals in groundwater has been limited to a small number of studies of extremely old groundwater (>100 ka). Here we present the first high-precision (<1‰) measurements of triple Ar isotopes ( 40 Ar, 38 Ar, 36 Ar) in groundwater. We introduce a model that distinguishes radiogenic 40 Ar from atmospheric 40 Ar by using the non-radiogenic Ar isotopes ( 36 Ar, 38 Ar) to correct for mass-dependent fractionation. Using this model, we investigate variability in radiogenic 40 Ar excess (Δ 40 Ar) across 58 groundwater samples collected from 36 wells throughout California (USA). We find that Δ 40 Ar ranges from ~0‰ (the expected minimum value) to +4.2‰ across three study areas near Fresno, San Diego, and the western Mojave Desert. Based on measurements from a network of 23 scientific monitoring wells in San Diego, we find evidence for a strong dependence of Δ 40 Ar on aquifer lithology. We suggest that Δ 40 Ar is fundamentally controlled by the weathering of old K-bearing minerals and thus reflects both the degree of groundwater-rock interaction, which is related to groundwater age, and the integrated flow through different geological formations. Future studies of Late Pleistocene groundwater may benefit from high-precision triple Ar isotope measurements as a new tool to better interpret 14 C- and 4 He-based constraints on groundwater age and flow.

Chemical Geology↗
USGS2022

Enhanced bioremediation of RDX and co-contaminants perchlorate and nitrate using an anaerobic dehalogenating consortium in a fractured rock aquifer

The potential neurotoxic and carcinogenic effects of the explosives compound RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) on human health requires groundwater remediation strategies to meet low cleanup goals. Bioremediation of RDX is feasible through biostimulation of native microbes with an organic carbon donor but may be less efficient, or not occur at all, in the presence of the common co-contaminants perchlorate and nitrate. Laboratory tests compared biostimulation with bioaugmentation to achieve anaerobic degradation of RDX, perchlorate, and nitrate; a field pilot test was then conducted in a fractured rock aquifer with the selected bioaugmentation approach. Insignificant reduction of RDX, perchlorate, or nitrate was observed by the native microbes in microcosms, with or without biostimulation by addition of lactate. Tests of the RDX-degrading ability of the microbial consortium WBC-2, originally developed for dehalogenation of chlorinated volatile organic compounds, showed first-order biodegradation rate constants ranging from 0.57 to 0.90 per day (half-lives 1.2 to 0.80 days). WBC-2 sustained degradation without daughter product accumulation when repeatedly amended with RDX and lactate for a year. In microcosms with groundwater containing perchlorate and nitrate, RDX degradation began without delay when bioaugmented with 10% WBC-2. Slower RDX degradation occurred with 3% or 5% WBC-2 amendment, indicating a direct relation with cell density. Transient RDX daughter compounds included methylene dinitramine, MNX, and DNX. With WBC-2 amendment, nitrate concentrations immediately decreased to near or below detection, and perchlorate degradation occurred with half-lives of 25 to 34 days. Single-well injection tests with WBC-2 and lactate showed that the onset of RDX degradation coincided with the onset of sulfide production, which was affected by the initial perchlorate concentration. Bioegradation rates in the pilot injection tests agreed well with those measured in the microcosms. These results support bioaugmentation with an anaerobic culture as a remedial strategy for sites contaminated with RDX, nitrate, and perchlorate.

New Mexico↗
USGS2024

Degradation kinetics of veterinary antibiotics and estrogenic hormones in a claypan soil

Veterinary antibiotics and estrogens are excreted in livestock waste before being applied to agricultural lands as fertilizer, resulting in contamination of soil and adjacent waterways. The objectives of this study were to 1) investigate the degradation kinetics of the VAs sulfamethazine and lincomycin and the estrogens estrone and 17β-estradiol in soil mesocosms, and 2) assess the effect of the phytochemical DIBOA-Glu, secreted in eastern gamagrass (Tripsacum dactyloides) roots, on antibiotic degradation due to the ability of DIBOA-Glu to facilitate hydrolysis of atrazine in solution assays. Mesocosm soil was a silt loam representing a typical claypan soil in portions of Missouri and the Central United States. Mesocosms (n = 133) were treated with a single target compound (antibiotic concentrations at 125 ng g−1 dw, estrogen concentrations at 1250 ng g−1 dw); a subset of mesocosms treated with antibiotics were also treated with DIBOA-Glu (12,500 ng g−1 dw); all mesocosms were kept at 60% water-filled pore space and incubated at 25 °C in darkness. Randomly chosen mesocosms were destructively sampled in triplicate for up to 96 days. All targeted compounds followed pseudo first-order degradation kinetics in soil. The soil half-life (t0.5) of sulfamethazine ranged between 17.8 and 30.1 d and ranged between 9.37 and 9.90 d for lincomycin. The antibiotics results showed no significant differences in degradation kinetics between treatments with or without DIBOA-Glu. For estrogens, degradation rates of estrone (t0.5 = 4.71–6.08 d) and 17β-estradiol (t0.5 = 5.59–6.03 d) were very similar; however, results showed that estrone was present as a metabolite in the 17β-estradiol treated mesocosms and vice-versa within 24 h. The antibiotics results suggest that sulfamethazine has a greater potential to persist in soil than lincomycin. The interconversion of 17β-estradiol and estrone in soil increased their overall persistence and sustained soil estrogenicity. This study demonstrates the persistence of these compounds in a typical claypan soil representing portions of the Central United States.

Chemosphere↗
USGS2017

Enhanced coal-dependent methanogenesis coupled with algal biofuels: Potential water recycle and carbon capture

Many coal beds contain microbial communities that can convert coal to natural gas (coalbed methane). Native microorganisms were obtained from Powder River Basin (PRB) coal seams with a diffusive microbial sampler placed downhole and used as an inoculum for enrichments with different nutrients to investigate microbially-enhanced coalbed methane production (MECoM). Coal-dependent methanogenesis more than doubled when yeast extract (YE) and several less complex components (proteins and amino acids) were added to the laboratory microcosms. Stimulated coal-dependent methanogenesis with peptone was 86% of that with YE while glutamate-stimulated activity was 65% of that with YE, and a vitamin mix had only 33% of the YE stimulated activity. For field application of MECoM, there is interest in identifying cost-effective alternatives to YE and other expensive nutrients. In laboratory studies, adding algal extract (AE) with lipids removed stimulated coal-dependent methanogenesis and the activity was 60% of that with YE at 27 d and almost 90% of YE activity at 1406 d. Analysis of British Thermal Unit (BTU) content of coal (a measure of potential energy yield) from long-term incubations indicated > 99.5% of BTU content remained after coalbed methane (CBM) stimulation with either AE or YE. Thus, the coal resource remains largely unchanged following stimulated microbial methane production. Algal CBM stimulation could lead to technologies that utilize coupled biological systems (photosynthesis and methane production) that sustainably enhance CBM production and generate algal biofuels while also sequestering carbon dioxide (CO 2 ).

International Journal of Coal Geology↗
USGS2023

Interlaboratory study: Testing reproducibility of solid biofuels component identification using reflected light microscopy

Considering global market trends and concerns about climate change and sustainability, increased biomass use for energy is expected to continue. As more diverse materials are being utilized to manufacture solid biomass fuels, it is critical to implement quality assessment methods to analyze these fuels thoroughly. One such method is reflected light microscopy (RLM), which has the potential to complement and enhance current standard testing, leading to improving fuel quality assessment and, ultimately, preventing avoidable air pollution. An interlaboratory study (ILS) was conducted to test the reproducibility of biomass fuels component identification using a reflected light microscopy technique. The exercise was conducted on thirty photomicrographs showing biomass and various undesired components (like plastics or mineral matter), which were purposely added (by the ILS organizers) to contaminate wood pellets and charcoal-based grilling fuels. Forty-six participants had various levels of difficulty identifying the marked components, and as a result, the percentage of correct answers ranged from 52.2 to 94.4%. Among the most difficult components to distinguish were petroleum products and inorganic matter. Various reasons led to the misidentification, including insufficient morphological descriptions of the components provided to participants, ambiguities of the nomenclature, limitations of the analytical and exercise method, and insufficient experience of the participants. Overall, the results indicate that RLM has the potential to enhance the quality assessment of biomass fuels. However, they also demonstrate that the petrographic classification used in this exercise requires further refinement before it can be standardized. While a new simplified classification of solid biomass fuels components was created as an outcome of this study, future research is necessary to refine the nomenclature, develop a microscopic morphological description of the components, and verify the accuracy of component identification with a follow-up ILS.

International Journal of Coal Geology↗
USGS2025

Component identification of solid biomass fuels using reflected light microscopy: Interlaboratory study 2

As nations transition toward sustainable energy systems , biomass has become a vital component of global energy portfolios. Derived from organic materials such as wood, agricultural residues, forestry byproducts, and organic waste, biomass is a renewable energy source with significant environmental and economic benefits. Responsible biomass energy production can improve waste management, reduce emissions of greenhouse gases, and mitigate environmental pollution. However, as the diversity of biomass-derived fuels increases, robust quality assessment methods are essential to ensure their efficiency, safety, and minimal environmental impact. Reflected light microscopy (RLM) is one such technique with the potential to complement conventional physico-chemical analyses by enabling a rapid identification of material constituents and impurities. To refine this methodology and evaluate the reproducibility of solid biomass component identification using RLM, an interlaboratory study (ILS) was conducted. The study involved the recognition of 58 components across 45 photomicrographs, with the participation of 65 scientists and students from 25 countries. The participants faced high difficulty identifying some of the marked components, and as a result, the percentage of correct answers ranged from 19.0 % to 98.3 %, with an average correct identification rate of 62.7 %. The most challenging aspects of the identification process included distinguishing between woody and non-woody (agro) biomass, accurately identifying petroleum-derived materials, and differentiating agro biomass from inorganic matter. The results suggest that while RLM is an important tool for characterizing solid biomass, further development of methodology guidelines and training are necessary to enhance its effectiveness. Future research should prioritize preparing detailed, image-rich, microscopic morphological descriptions of biomass fuel components, which could improve the accuracy and reliability of using RLM in biomass fuel characterization.

International Journal of Coal Geology↗
USGS2021

Hotspot dune erosion on an intermediate beach

A large, low pressure Nor’easter storm and Hurricane Joaquin contributed to multiple weeks of sustained, elevated wave and water level conditions along the southeastern Atlantic coast of the United States in Fall 2015. Sea level anomalies in excess of 1 m and offshore wave heights of up to 4 m were recorded during these storms, as observed at the U.S. Army Corps of Engineers’ Field Research Facility in Duck, NC, USA. In response to these energetic oceanographic conditions, there were highly variable morphologic changes to the dune over short spatial scales (<km) which included a range of responses from vertical dune scarping to no measureable response. The portion of the study area with the largest dune erosion occurred at a location fronted by an abnormally deep nearshore bathymetric feature, which altered surf-zone waves and hydrodynamics. The pre-storm beach and dune topography also varied throughout the study area, additionally influencing the frequency of dune collision and contributing to the spatially variable erosion patterns. This work uses field datasets and numerical modeling tools to investigate the causation of hotspot dune erosion at the Field Research Facility. Three different numerical models were tested against the available data in order to assess model skill at resolving complex spatial dune erosion patterns. The three models successfully reproduce the general spatial trends in alongshore variable responses, although not necessarily the details of profile response or net erosion magnitude. Analysis of the model outputs, in conjunction with the available field data, suggests that the observed hotspot dune erosion is related to a complex combination of both topographic and bathymetric controls on the processes driving dune erosion. Therefore, the most simplistic model tested, which only accounts for alongshore variations in topographic profile details, can only predict hotspot dune erosion in locations where steep beach and/or dune topography is the primary control on collisional dune impacts. The higher fidelity models , which account for feedback effects from subaqueous morphology, are similarly able to predict the locations of maximum hotspot erosion, but are sensitive to beach over-steepening and/or errors in wave runup calculations that can lead to over-prediction of simulated dune erosion. This work highlights that numerous existing tools are capable of identifying the foredune regions at most risk from hotspot erosion, as well as the need for continued research to improve representation of all relevant intra-storm morphodynamic processes.

Coastal Engineering↗
USGS2026

Genetic biocontrol strategy considerations for mosquito control in the Pacific Island Countries and Territories

Mosquito-borne diseases pose an existential threat to the health, economies, and unique ecosystems of Pacific Island Countries and Territories (PICTs). The remoteness of these islands, combined with the presence of highly competent mosquito vectors, complicates disease surveillance and vector control efforts. In response, the PICTs have become a focal point for the development and application of Genetic BioControl (GBC) technologies designed to break vector-borne disease transmission cycles. However, the application of GBC tools in this region warrants careful consideration of its unique history, including a legacy of colonialism, and challenges associated with logistic hurdles. Through meaningful community engagement and authentic collaborations, drawing from local knowledge, and building local capacity, the sustainable, efficient, and effective deployment of GBC tools may be achieved.

Current Opinion in Insect Science↗