Debris Loads Research Articles

Wave–Current Impulsive Debris Loading on a Coastal Building Array

Wave–Current Impulsive Debris Loading on a Coastal Building Array

Flood Vulnerability Study of a Roadway Bridge Subjected to Hydrodynamic Actions, Local Scour and Wood Debris Accumulation

The increased occurrence and intensity of flooding events have represented a real threat to bridge reliability and end-user safety. As flood vulnerability assessment is a valuable tool for enhancing the resilience of bridges to climate change, it is of interest to push the development of such methods. To this end, a computationally efficient methodology to assess the flood vulnerability of a bridge was developed and implemented in a case study. A particular focus was devoted to modelling wood debris loads on the bridge pier, for which two different approaches were implemented. The first is a standards-based approach, whereas the second is based on up-to-date research data. The results indicate that the second approach is less conservative as it leads up to a 40% higher exceedance probability for the considered limit states. The interaction between wood debris loads and local scour was also examined and proved to have a relevant impact on the vulnerability of the bridge. These results highlight the shortcomings of the existing standards in providing accurate results. It is perceived that not only will the new quantitative tool be valuable in ensuring optimal bridge design, but it will also be beneficial for assessing bridge risk mitigation measures.

Allometric equations and wood density parameters for estimating aboveground and woody debris biomass in Cajander larch (Larix cajanderi) forests of northeast Siberia

Abstract. Boreal forests are particularly vulnerable to climate warming, which increases the occurrence of natural disturbances, such as fires and insect outbreaks. It is therefore essential to better understand climate-induced changes in boreal vegetation dynamics. This requires accurate estimates of variations in biomass across regions and time. This remains challenging in the extensive larch forests of northeast Siberia because of the paucity of allometric equations and physical properties of woody debris needed for quantifying aboveground biomass pools from field surveys. Our study is the first to present values of mean squared diameter (MSD) and specific gravity that can be used to calculate fine dead and downed woody debris loads in Cajander larch (Larix cajanderi) forests using the line-intersect sampling approach. These values were derived from field measurements collected in 25 forest stands in the Republic of Sakha, Russia, and compared with values reported for other prevalent boreal tree species. We developed allometric equations relating diameter at breast height (DBH, at 1.3 m) to stem wood, stem bark, branches, foliage, and aboveground biomass based on measurements of 63 trees retrieved from previous studies. Differences between our allometric models and existing equations were assessed in predicting larch aboveground biomass in 53 forest stands sampled in the Republic of Sakha. We found that using fine woody debris (FWD) parameters from other boreal tree species and allometric equations developed in other regions may result in significantly lower biomass estimates in larch-dominated forests of northeast Siberia. The FWD parameters and allometric equations presented in our paper can be used to refine estimates of aboveground biomass in Cajander larch forests in northeast Siberia.

The Influence of Slash Management Practices on Water and Nutrient Dynamics in Longleaf Pine Forests

(1) Silvicultural applications that manipulate woody debris loading and the structural composition of a forest can have both short and long-term effects on biogeochemical cycling. Longleaf pine forests have been the historically dominant community types throughout much of the Southeastern United States. Fire exclusion, hardwood encroachment, and resource exploitation have severely reduced the amount of remaining longleaf pine habitats, making ecological restoration necessary. The silvicultural treatments used to reestablish these communities have been widespread, leading to some skepticism regarding the sustainability of certain restoration practices. (2) This study aimed to understand how overstory manipulation and woody debris management affected soil water retention rates and nutrient availability. Using a randomized complete block design, abiotic responses to biomass harvesting, conventional harvesting, and mastication treatments were measured across a soil moisture gradient in the South Carolina sandhills. (3) Our findings indicate that mastication increased soil moisture retention rates by 37% and 41%, on average, compared to conventional harvesting and biomass harvesting, respectively. (4) Additionally, soil nutrient stocks did not decline following any management practice, indicating that both biomass harvesting and mastication treatments may not necessarily impact site productivity in a negative manner. These findings imply that mastication treatments keep moisture retention high and do not immediately change soil nutrient availability in longleaf pine forests. Long-term vegetation response studies should continue to document successional trends in conjunction with moisture retention rates and long-term nutrient pulsing.

An integrative assessment of the plastic debris load in the Mediterranean Sea.

The Mediterranean Sea is recognized as one of the most polluted areas by floating plastics. During the Tara Mediterranean expedition, an extensive sampling of plastic debris was conducted in seven ecoregions, from Gibraltar to Lebanon with the aim of providing reliable estimates of regional differences in floating plastic loads and plastic characteristics. The abundance, size, surface, circularity and mass of 75,030 pieces were analyzed and classified in a standardized multi-parameter database. Their average abundance was 2.60 × 105 items km-2 (2.25 × 103 to 8.50 × 106 km-2) resulting in an estimate of about 650 billion plastic particles floating on the surface of the Mediterranean. This corresponds to an average of 660 metric tons of plastic, at the lower end of literature estimates. High concentrations of plastic were observed in the northwestern coastal regions, north of the Tyrrhenian Sea, but also off the western and central Mediterranean basins. The Levantine basin south of Cyprus had the lowest concentrations. A Lagrangian Plastic Pollution Index (LPPI) predicting the concentration of plastic debris was validated using the spatial resolution of the data. The advanced state of plastic degradation detected in the analyses led to the conclusion that stranding/fragmentation/resuspension is the key process in the dynamics of floating plastic in Mediterranean surface waters. This is supported by the significant correlation between pollution sources and areas of high plastic concentration obtained by the LPPI.

Using long-term citizen science data to distinguish zones of debris accumulation.

Studies show that a driver of coastal debris is the rate between debris deposition and resuspension; however, the influence of beach zone topography on the distribution of debris remains poorly understood. Using five years of marine debris data collected by the COASST citizen science program, we explored the spatiotemporal trends in debris abundance within two regions of the United States Pacific Northwest and investigated whether higher debris loads are associated with beach zones that have a higher propensity to trap debris. We found that beaches with larger wood zones had higher debris loads, adding to the growing evidence that backshore areas of beaches act as sinks for debris. Higher debris loads were also associated with beaches that had larger wrack zones suggesting that onshore transport from the marine reservoir is a dominant source of debris. This study provides a long-term baseline of marine debris which managers could use to inform source reduction interventions.

Micro-contaminant, but immense impact: Source and influence of diethyl phthalate plasticizer on bottom-dwelling fishes

Sustainable plastic-waste management is becoming increasingly challenging as enormous loads of plastic debris regularly accumulate in susceptible ecosystems. The microplastic (MP) particles generated from these plastic wastes are imposing additional threats to these ecosystems due to their small size as well as their ability to adsorb and carry toxic chemicals. The current investigation deals with one such MP-originated toxicant, diethyl phthalate (DEP), and its impact on two species of freshwater loaches from the Western Ghats of India, Lepidocephalichthys thermalis and Indoreonectes evezardi. The MP samples were collected from the sediments of the Mula River and characterized using spectroscopic methods and scanning electron microscopy. Polymers, such as polyvinyl chloride and polypropylene, were identified in the collected MPs. GC-MS analysis of the MP extracts revealed the presence of DEP, confirming the MP waste as a potential source of DEP pollution. Further, to evaluate the effect of DEP on survival of selected loaches, L. thermalis and I. evezardi were exposed to DEP concentrations (18.75–300 mg L−1) and the lethal DEP dose (LC50) was estimated to be 44.53 mg L−1 for L. thermalis and 34.64 mg L−1 for I. evezardi. Fishes were further exposed to sub-lethal DEP concentration for one day (Short term exposure: STE) or eight days (Long term exposure: LTE) to analyze the histological condition and oxidative status of the liver in response to DEP treatment. Histology revealed congestion of sinusoids and vacuolization after the LTE. Higher lipid peroxidation levels were also measured in the livers of both species treated with DEP, which indicated DEP-mediated oxidative damage. The antioxidant enzymes including superoxide dismutase, catalase, peroxidase and glutathione-S-transferase displayed elevated activities in response to STE and LTE of DEP. Collectively, the results demonstrate that MPs in the Mula River are a potential source of DEP. The findings also show that DEP exposure can be fatal to freshwater fishes such as loaches, possibly by causing increased oxidative damage to the hepatic system.

Damage Analysis and Close-Range Radar Observations of the 13 April 2019 Greenwood Springs, Mississippi, Tornado during VORTEX-SE Meso18-19

Abstract A tornado outbreak occurred across the Southeast United States on 13–14 April 2019, during the Verification of the Origins of Rotation in Tornadoes Experiment–Southeast (VORTEX-SE) Meso18-19 experiment. Among the most noteworthy events was a pair of large tornadoes in Monroe County, Mississippi, near the Columbus Air Force Base (GWX) Weather Surveillance Radar–1988 Doppler (WSR-88D). The second tornado, near the Greenwood Springs community, formed within the “no data” region near the radar and passed about 900 m to its east, rapidly strengthening into an intense tornado. This tornado produced forest devastation and electrical infrastructure damage up to at least EF4 intensity. The maximum radial velocity from GWX was 81.5 m s−1 (182 mph) in a resolution volume centered at 56 m (183 ft) above radar level. This paper presents a damage survey of the Greenwood Springs tornado and compares this assessment to the GWX data. A displacement of the maximum forest damage from the maximum radial velocity, despite the radar beam sampling <100 m ARL, is documented, as well as other likely effects of debris loading by the tornado on the observed radar signatures. The radar observations are placed into context with past mobile radar studies to illustrate the unique nature of this dataset. The relationship between radar data and damage observations, the implications for tornado structure in rough terrain and land cover, and the use of forest damage and radar data in tornado intensity estimation are discussed. Significance Statement This study showcases radar and damage observations of an intense tornado in a forested region of Mississippi. The formation of the tornado within 1 km of a WSR-88D allowed for near-surface radar observations to be collected as significant tree destruction was occurring. Doppler velocities below 60 m above radar level (ARL), near tree canopy top, exceeded 80 m s−1. Tree damage patterns were complicated while the tornado was near maximum intensity. The most severe tree damage was notably displaced from the highest radar-observed velocities, despite the radar sampling as low as 45 m ARL. These findings highlight challenges in utilizing radar data to estimate tornado intensity and structure, particularly in a region of relatively high surface and terrain roughness.

Experimental investigation on sodium compatibility of magnesia during corium relocation in SFR for core catcher application

Core melt accident is a very low probability event in Sodium Cooled Fast Reactors (SFRs) due to presence of several inherent and engineered safety features. However, such accidents are considered in the design of reactor to ensure safe mitigation and containment. Core Catcher (CC) is a passive device installed below the core in lower plenum of reactor vessel to retain and cool the degraded core debris in subcritical state. In the earlier reactors, partial core melting (typically seven subassemblies) was considered as design criteria for CC. For future SFRs, retention and cooling of whole core has to be considered as design basis in view of enhanced safety. Whole core relocation would impose significantly higher thermal load on structural material of the CC. A sacrificial lining of refractory ceramic materialis under development for thermal protection of CC during whole core retention. Based on preliminary studies, sintered magnesia has been chosen as candidate material and experiments are conducted to investigate its thermal stability in sodium at high temperature. Standard test specimens of sintered magnesia were exposed to sodium at its boiling point under simulated loading of core debris corresponding to whole core relocation in a medium size SFR. Posttest characterization was carried out using XRD and SEM coupled with ESD techniques. Changes in compressive strength and ultrasonic pulse velocity of specimens after high temperature sodium exposure were measured to assess degradation of the specimens. The experimental results indicated satisfactory performance of high purity sintered magnesia bricks for application to the CC as sacrificial material.

The Dodge City Tornadoes on 24 May 2016: Understanding Cycloidal Marks in Surface Damage Tracks and Further Analysis of the Debris Cloud

Abstract Mobile, polarimetric radar data were collected on a series of tornadoes that occurred near Dodge City, Kansas. A poststorm survey revealed a series of tornadic debris swaths in several dirt fields and high-resolution pictures of the tornado documented the visual characteristics of the tornado and the lofted debris cloud. The main rotational couplet associated with the tornado was identified in the single-Doppler velocities; however, no secondary rotational couplets were resolved in the low-level data performed during two consecutive volume scans. Numerical simulations have suggested that cycloidal damage swaths can result when debris is deposited as the low-level inflow turns upward in the corner region of the updraft annulus of the tornado core. This mechanism can dominate even when suction vortices are present in the simulations and can produce these swaths in the absence of these smaller-scale vortices. It is hypothesized that the observed cycloidal damage swaths were a result of the low-level inflow in the corner region of the tornado and not by the existence of suction vortices. Polarimetric data were combined with photographs of the tornado in order to document the lofted debris cloud and its relationship with the funnel. This analysis provided an opportunity to investigate whether recent findings describing the cross-correlation coefficient ρhv and differential reflectivity ZDR signatures of the lofted debris cloud could be replicated. Regions of low ρhv at the periphery of the funnel cloud suggesting high debris loading and a column of negative ZDR centered on the tornado believed to be produced by common debris alignment were noted. Significance Statement It is well known that some tornadoes produce smaller-scale vortices that rotate around the central axis of the main circulation. In addition, numerous aerial photographs have documented cycloidal debris marks within tornado damage tracks that traverse open fields. The prevailing theory shown in numerous textbooks is that these marks are produced by these vortices. The current study suggests that this widely accepted model for producing these marks may be incorrect. It is suggested that these cycloidal marks are produced by the main tornado circulation and not by the smaller-scale vortices in this case.

Damage Estimation of a Concrete Pier When Exposed to Extreme Flood and Debris Loading

The structural safety and serviceability during extreme weather, such as floods and storms, is critical. Due to global warming in the last decades, the increase in the intensity of natural disasters, i.e., flood loading and the durability of the road structures and infrastructures, is becoming critical. Bridges and structures lose their capacity because of ageing over time. On the other hand, the load intensity is another reason for the structural damage. Debris loading due to the flooding on bridges is one of the reasons for the increase in flood loading and eventually structural damage. Measuring the level of structural damage under extreme events is vital in determining the vulnerability and resilience of structures during a disaster. A damage index (DI) can be defined as a measurement tool for the levels of structural damage. Oftentimes, damage indices are developed to measure the deterioration of the system under earthquake loading. Little work has been published on damage indices (DIs) under flood loading, where a uniform pressure is applied to a structure. This paper presents a comprehensive review of DIs published in the literature and compares two approaches to assess the system’s damage utilising finite element methodologies. The structure model developed in the ABAQUS software package is used to predict the failure of a concrete component under applied lateral loading. The model is validated using published experimental work. The model is verified, and then it is used to compute the damage indicators using two primary techniques, including a deflection-based method and an energy loss-based approach. Using the two offered DIs, the change in damage levels is displayed underwater flow uniform loading. A comparison of the two methods is conducted. In this paper, differences between the two concepts are analysed and presented.

Floating microplastic loads in the nearshore revealed through citizen science

Research on plastic pollution has rapidly expanded in recent years and has led to the discovery of vast amounts of microplastics floating on the surface of subtropical oceanic gyres. However, the distribution of floating plastic in the ocean is still poorly constrained, and there is a lack of information from a few meters from the coastline where the largest plastic emissions take place. Here, we provide a comprehensive study on the loads of plastic debris in the coastal surface waters of the NW Mediterranean Sea using data from 124 manta trawl deployments collected along 7 months by citizen scientists. Our results reveal that pollution by microplastics in the nearshore is likely subject to seasonal variations associated to a combination of hydrodynamic and anthropogenic pressures. The high proportions of microplastics found indicate that potential breakdown of plastics in the nearshore may take place in line with previous works. We prove that citizen science is a powerful tool in plastic research to monitor microplastics in the nearshore as it provides scientifically meaningful results while stimulating citizen engagement. Future studies may benefit from targeting specific scientific open questions by using the citizen science methodological approach presented here.

Shrimp and microplastics: A case study with the Atlantic ditch shrimp Palaemon varians

Many invertebrate species inhabit coastal areas where loads of plastic debris and microplastics are high. In the current case study, we exemplarily illustrate the principal processes taking place in the Atlantic ditch shrimp, Palaemon varians, upon ingestion of microplastics. In the laboratory, shrimp readily ingested fluorescent polystyrene microbeads of 0.1–9.9 µm, which could be tracked within the widely translucent body. Ingested food items as well as micro-particles cumulate in the stomach where they are macerated and mixed with digestive enzymes. Inside the stomach, ingested particles are segregated by size by a complex fine-meshed filter system. Liquids and some of the smallest particles (0.1 µm) pass the filter and enter the midgut gland where resorption of nutrients as well as synthesis and release of digestive enzymes take place. Large particles and most of the small particles are egested with the feces through the hindgut. Small particles, which enter the midgut gland, may interact with the epithelial cells and induce oxidative stress, as indicated by elevated activities of superoxide dismutase and cellular markers of reactive oxygen species. The shrimp indiscriminately ingest microparticles but possess efficient mechanisms to protect their organs from overloading with microplastics and other indigestible particles. These include an efficient sorting mechanism within the stomach and the protection of the midgut gland by the pyloric filter. Formation of detrimental radical oxygen species is counteracted by the induction of enzymatic antioxidants.

Potential of Recycle Marine Debris in Pluit Emplacement, Jakarta to Achieve Sustainable Reduction of Marine Waste Generation

Marine debris is one of the global problems due to human activities. One of the biggest loads of marine debris is in the city of Jakarta, namely the Pluit Emplacement. Emplacement Pluit is a special location for managing marine debris in Jakarta, with the largest burden of marine debris problems discharged from urban areas. This study analyses aquatic waste's generation or marine debris, composition, and recycling potential at the Pluit Emplacement. The research process starts with formulating the problem, conducting a literature review, collecting data, and analyzing it under ideal conditions and planning. This research was conducted by sampling for seven consecutive days, and load count analysis to determine the generation and composition of marine debris. The marine debris composition is grouped using a load based on the volume/volume (v/v) ratio. The generation of marine debris in the Pluit Emplacement can reach 230 m3/day or 303.6 tons/day. However, this value is higher than other areas in Jakarta and other areas in Indonesia. The composition of marine debris consists of Straw (PET), Food packaging, Drink cup, PET Bottle, Miscellaneous packaging, Plastic bags (PP), Plastic toys (HDPE), Metal, Styrofoam, biodegradable waste (wood, twigs and leaves) which is 0.1%; 3.1%; 2.2%; 22.5%; 4.0%; 0.7%; 0.8%; 0.6%; 3.1%; and 62.8%, respectively. The level of potential for recycling of Pluit's marine debris is 67.86%, with the greatest potential being from the utilization of biodegradable waste into compost or recycling of plastic waste, especially PET plastic. This considers the absence of previous sustainable marine debris processing. These findings can be one of the considerations for the government in making decisions to carry out appropriate planning according to the characteristics of marine debris, that this research can also be used as consideration for regions and even other countries in the characterization and planning of marine debris management.

Effect of structure orientation and debris initial orientation on peak debris loading during tsunami: An experimental and numerical investigation

The impact of the debris during extreme events is one of the major factors that has to be accounted for the critical design of the coastal structures. This study, investigates the effect of peak impact load due to combination of debris and the hydraulic bore on a structure with varying orientation angles. The bore profile is generated by using dam-break condition and a shipping container that is based on the ISO criteria fitted with an accelerometer, is used as a debris in this study. The peak impact load due to the combination of debris and the bore is measured by the multi-axial load cell that is mounted at the bottom of the modelled structure. It is observed that the orientation angle of the structure plays a major role in identifying the peak debris impact load. Therefore, a new coefficient of orientation angle, ‘Cθ’ is proposed to modify the basic impulse-momentum equation; that accounts for the excess loads on the structure. The experimental study is reproduced and simulated using particle based numerical method ‘δ-SPH’ and the results are validated with experimental observations. Further, the δ-SPH model is used to carry out detailed parametric study by varying the debris mass.

Development of Al – Fly ash Composites: A step towards sustainability

The use of mechanical waste in current assembling is a major jump towards supportable turn of events. Fly ash is an industry waste obtained from thermal power stations during burning of pounded coal. Fly debris based composites having prevalent characteristics in correlation with alloy metals and particularly the aluminium matrix composites have larger scope of acknowledgment in various regions to replace the use of iron and prepares and discovered applications in aviation and vehicle sector. The present work endeavours one such use and lessening the requirement for removal of fly debris which thus makes extensive harm the climate. This work manages the creation through fluid metallurgy course mix projecting of Al amalgam with 0–5-8% load of fly debris and micro structural investigation through optical microscopy, SEM, XRD and EDX testing of aluminium fly ash composite to recognize the fly debris particle. The XRD examination showed that the translucent period of the fly debris was a viable supported stage. Meanwhile, the optical and SEM micrographs of the composite examples demonstrated that fly debris could be responded or settled in the grid of the aluminium. The micro hardness examinations were additionally used to concentrate on the Al–fly debris composites.

An Integrative Assessment of the Plastic Debris Load in the Mediterranean Sea

An Integrative Assessment of the Plastic Debris Load in the Mediterranean Sea

3D-Printed Topological MoS2/MoSe2 Heterostructures for Macroscale Superlubricity.

Superlubricity is a fascinating phenomenon which attracts people to continuously expand ultralow friction and wear from microscale to macroscale. Despite the impressive advances in this field, it is still limited to specific materials and extreme operating conditions. Introducing a heterostructure with intrinsic lattice mismatch into delicate topologies mimicked from nature provides a promising alternative toward macroscopic superlubricity. Herein, 3D-printed MoS2/MoSe2 heterostructures with bioinspired circular-cored square/hexagonal honeycomb topologies were developed. Compared to 3D-printed Al2O3, all topological structures with both high hardness and excellent flexural strength achieve more than 30% decrease in the friction coefficient. The circular-cored hexagonal honeycomb composite with 30% area density exhibits a stable ultralow friction coefficient of 0.09 and a low wear rate of 2.5 × 10-5 mm3·N-1 m-1 under 5 N. Even under 10 N, a highly desirable coefficient value of 0.08 can be maintained within 370 s. The extraordinary ultralow friction could be attributed to the small contact area, high lubricant mass loading, efficient collection and storage of both abrasive debris and lubricant, and the self-orientation in the lubricating film. This work provides new insights into developing high-efficiency lubrication devices and aids in the industrial application of macroscopic superlubricity in future life.

Development and Application of STORMTOOLS Design Load (SDL) Maps

Under the STORMTOOLS initiative, maps of the impact of sea level rise (SLR) (0 to 12 ft), nuisance flooding (1–10 yr), 25, 50, and 100 yr storms, and hindcasts of the four top ranked tropical storms have been developed for the coastal waters of Rhode Island (RI). Estimates of the design elevations, expressed in terms of the Base Flood Elevation (BFE) and thus incorporating surge and associated wave conditions, have also been developed, including the effects of SLR to facilitate structural design. Finally, Coastal Environmental Risk Index (CERI) maps have been developed to estimate the risk to individual structures and infrastructure. CERI employs the BFE maps in concert with damage curves for residential and commercial structures to make estimates of damage to individual structures. All maps are available via an ArcGIS Hub. The objective of this senior design capstone project was to develop STORMTOOLS Design Load maps (SDL) with a goal of estimating the hydrostatic, hydrodynamic, wave, and debris loading, based on ASCE/SEI 7–16 Minimum Design Standards methods, on residential structures in the RI coastal floodplain. The resulting maps display the unitized loads and thus can be scaled for any structure of interest. The goal of the maps is to provide environmental loads that support the design of structures, and reduce the time and cost required in performing the design and the permitting process, while also improving the accuracy and consistency of the designs. SDL maps were generated for all loads, including the effects of SLR for a test case: the Watch Hill/Misquamicut Beach, Westerly, along the southern RI coast. The Autodesk Professional Robot Structural Analysis software, along with SDL loading, was used to evaluate the designs for selected on-grade and pile-elevated residential structures. Damage curves were generated for each and shown to be consistent with the US Army Corps of Engineers empirical damage curves currently used in CERI.

Long-term impacts of silvicultural treatments on wildland fuels and modeled fire behavior in the Ridge and Valley Province, Virginia (USA)

Active forest management operations, such as regeneration harvests, can reduce hazardous fuel loads and alter fuel structure, potentially minimizing extreme wildfire conditions while maintaining ecosystem services, such as wildlife habitat and water quality. Regeneration harvests of differing intensities (clearcut, high-retention shelterwood, and low-retention shelterwood) were first applied between 1995 and 1996 to three sites on the George Washington-Jefferson National Forest in the Ridge and Valley Province of Virginia, USA. Over two decades after the clearcut was conducted and 11–12 years after the overwood was removed in the shelterwood stands, woody debris, litter, and duff masses and depths were quantified. One-hour fuel loads were greater in clearcut units than in high-retention shelterwood, low-retention shelterwood, or control units. Ten-hour fuel loads were greater in clearcut and low-retention shelterwood units than in high-retention shelterwood and control units. No significant differences in 100-hour fuels were observed between treatments. Control units contained more rotten and total 1000-hour fuels than all other treatments. The total woody debris load was less in the clearcut and high-retention shelterwood than in the low-retention shelterwood and control. High-retention shelterwood woody fuel depth was greater than clearcut woody fuel depth. Litter and duff loads were less in treated units than in the control units. Total fuel load (woody fuel load + litter load + duff load) was greater in the control than the silvicultural treatments. Litter depth did not differ between treatments, while duff depth was greater in the control than in the treated units. Using the computer modeling software, BehavePlus 6.0.0, these alterations to fuel loads and depths led to increased values in the control units for six fire behavior parameters. Predicted surface flame length in the low-retention shelterwood was the only modeled value that was not less than control values. Overall, these results indicated that harvest intensity and timing may have long-term effects on down and dead woody fuels, forest floor depth, and potential fire behavior. Clearcutting reduced fire behavior most, followed by the high-retention shelterwood system. The potential differences in slash and debris generated by varying shelterwood systems may impact long-term fuel and fire dynamics.