Edge Effects Research Articles

Distribution, Diversity, and Ecological Risks of Microplastics in Mangrove Ecosystems of a Southeastern Chinese Estuary

Mangrove ecosystems, serving as critical barriers at land–sea interfaces, face increasing threats from microplastic pollution. This study investigates the spatial distribution, diversity, and ecological risks of microplastics in sediments from the Zhangjiang Estuary mangroves, in southeastern China. Sampling was conducted along two gradients: upstream–downstream and interior–edge habitats. The results revealed an average microplastic abundance of 219.5 ± 21.7 items·kg−1, dominated by fragments (53.3%) and fibers (35.0%). Additionally, 27.8% of the particles were in the 63–200 μm range, while 38.3% fell within the 200–500 μm range. A longitudinal decline in abundance from upstream to downstream was observed. Meanwhile, interior habitats exhibited significantly higher microplastic accumulation (292.86 ± 31.49 items·kg−1) than edge zones (142.50 ± 17.87 items·kg−1) (p < 0.05). The diversity index decreased downstream, with higher diversity in interior habitats, likely due to reduced terrestrial microplastic inputs and stronger tidal sorting in those areas. The ecological risk assessments indicated lower risks in Zhangjiang mangroves compared to global counterparts, though risks were elevated in interior habitats due to higher abundances of hazardous polymers (PVC, PS, PE). This study highlights the role of mangroves as microplastic sinks and advocates for multidimensional risk assessments integrating physical characteristics to guide conservation strategies in vulnerable estuarine ecosystems.

Edge effects on amphibians in transformed tropical dry forest landscapes: The relationship between functional and taxonomic diversity

Edge effects on amphibians in transformed tropical dry forest landscapes: The relationship between functional and taxonomic diversity

Negative effects of forest edges and canopy opening on moth communities

Negative effects of forest edges and canopy opening on moth communities

Parametric study of permanent magnet eddy current brake considering demagnetization, temperature, edge, and skin effects: Numerical and experimental investigation

Parametric study of permanent magnet eddy current brake considering demagnetization, temperature, edge, and skin effects: Numerical and experimental investigation

Characterising tropical oyster reefs: invertebrate-environment associations and a newly documented reef building species.

Characterising tropical oyster reefs: invertebrate-environment associations and a newly documented reef building species.

Optimizing precision conservation with on-farm precision experiment data: The role of crop insurance and spatially variable profit.

Optimizing precision conservation with on-farm precision experiment data: The role of crop insurance and spatially variable profit.

Edge effect impacts on forest structure and carbon stocks in REDD+ projects: An assessment in the Amazon using UAV-LiDAR

Edge effect impacts on forest structure and carbon stocks in REDD+ projects: An assessment in the Amazon using UAV-LiDAR

Interface Size-Dependent Changes in Activity of Water Splitting Electrocatalysts.

The traditional method of reporting electrocatalytic activity by normalizing current to the geometric area (mA cm-2) often results in exaggerated activity for electrodes smaller than 1 cm2. Using stainless steel 304 (SS-304) and Ni foam electrodes of varying sizes (0.3-2.1 cm2), along with two modified electrodes with faster kinetics (NiFe LDH for the OER in 1.0 M KOH and Pt/C for the HER in 0.5 M H2SO4), we investigated the oxygen and hydrogen evolution reactions. Our results reveal a 2-3-fold exaggeration in activity with electrodes smaller than 1 cm2, primarily due to smaller double layers, lower iR drop, and a high edge-to-size ratio, leading to stronger edge effects. These findings suggest that electrodes smaller than 1 cm2 may not be ideal for accurately depicting electrocatalytic activity that is always and almost represented in current densities (in mA cm-2), as geometric area normalization leads to misleading overstatements of performance. In contrast, smaller electrodes may still be useful for studies where specific and accurate sensing of certain analytes (often masked by large iR drop and mass-transport limitations) are necessary (e.g., electrochemical sensing of various analytes), as they offer advantages like lower iR drop and less affected by mass-transport limitations.

Real-Time Bacterial Monitoring and Drug Screening Using the Interdigitated Wave-Shaped Biosensor (IWE), Combined with FEM and Molecular Docking Studies.

Rapid and accurate detection of bacteria in water, food, and air is essential for protecting public health, especially amid rising antimicrobial resistance and outbreaks. Traditional detection methods, while reliable, are time-consuming, resource-intensive, and unsuitable for real-time monitoring. Similarly, antibiotic efficacy assessment requires laborious culturing, delaying treatment. This study presents an interdigitated wave-shaped electrode (IWE) capacitance biosensor for real-time bacterial monitoring and drug evaluation. The IWE, optimized via COMSOL simulations addresses edge effects and enhances electric field uniformity and capacitance sensitivity. Simulated capacitance in PBS (5.21 × 10-7 F at 1 Hz) closely matched the experimental value (3.19 × 10-7 F at 1 Hz), validating the optimized IWE design. Integrated with a 16-channel multiplexer, the biosensor enabled high-throughput, real-time detection of Staphylococcus aureus, Bacillus cereus, and Escherichia coli over a range of 10 to 104 CFU/mL, with a detection limit of 10 CFU/mL. Molecular docking simulations were employed to assess antibiotics, which were subsequently tested through real-time capacitance measurements. A decrease in the capacitance indicated effective bacterial inhibition at concentrations exceeding the minimum inhibitory concentration. Results were further validated through disk diffusion assays and scanning electron microscopy, confirming the accuracy. This integrated approach demonstrates the biosensor's potential for real-time pathogen detection and antimicrobial susceptibility assessment.

Deer Vigilance and Movement Behavior Are Affected by Edge Density and Connectivity

ABSTRACTAnimal behavior is an important component of individual, population, and community responses to anthropogenic habitat alteration. For example, antipredator behavior (e.g., vigilance) and animal movement behavior may both be important behavioral responses to the increased density of habitat edges and changes in patch connectivity that characterize highly modified habitats. Importantly, edge density and connectivity might interact, and this interaction is likely to mediate animal behavior: linear, edge‐rich landscape features often provide structural connectivity between patches, but the functional connectedness of patches for animal use could depend upon how edge density modifies animal vigilance and movement. Using remote cameras in large‐scale experimental landscapes that manipulate edge density (high‐ vs. low‐density edges) and patch connectivity (isolated or connected patches), we examined the effects of edge density and connectivity on the antipredator behavior and movement behavior of white‐tailed deer (Odocoileus virginianus). Deer vigilance was 1.38 times greater near high‐density edges compared to low‐density edges, regardless of whether patches were connected or isolated. Deer were also more likely to move parallel to connected high‐density edges than all other edge types, suggesting that connectivity promotes movement along high‐density edges. These results suggest that increases in edge density that accompany human fragmentation of existing habitats may give rise to large‐scale changes in the antipredator behavior of deer. These results also suggest that conservation strategies that simultaneously manipulate edge density and connectivity (i.e., habitat corridors) may have multiple effects on different aspects of deer behavior: linear habitat corridors were areas of high vigilance, but also areas where deer movement behavior implied increased movement along the habitat edge.

Nanoindentation Response of Monocrystalline Copper via Molecular Dynamics: Anisotropic Edge Effects.

In the nanoindentation testing of metallic materials, mechanical properties often decrease significantly when the indentation position shifts from the central region to the edge due to edge effects, leading to premature edge failure and potential device malfunctions. In this work, molecular dynamic (MD) simulations were conducted to investigate the anisotropic edge effects of nanoindentation on monocrystalline copper with a specific crystal orientation. The results reveal that changes in indentation position strongly influence surface collapse and lateral pile-up behaviors. Notably, edge positions resulted in significant reductions in indentation force and hardness, accompanied by pronounced anisotropy in nanoindentation hardness. Additionally, distinct von Mises stress distributions were observed at different indentation positions, highlighting the crystallographic orientation's role in modulating edge effects. This study provides new insights into the atomic-scale mechanisms underlying edge effects in metallic materials and their anisotropic characteristics.

Optimization of ecological landscape of urban human settlements under edge effect

Optimization of ecological landscape of urban human settlements under edge effect

Moisture absorption behavior of CFRP: Finite element analysis and machine learning coupled method

In recent years, carbon fiber reinforced polymer (CFRP) has been widely used in the lightweight design of structures. With the increasing frequency of acid rain, the service environment of CFRP has become more acidic. Furthermore, compared to metals, CFRP is more susceptible to degradation in acidic conditions. Therefore, this study combines finite element (FE) analysis with machine learning techniques to investigate the moisture absorption characteristics of CFRP in acidic environments. First, acid-thermal aging experiments were conducted, and the moisture absorption data were fitted using the three-dimensional Fick law. These parameters were then employed to establish an FE model of CFRP moisture absorption in ABAQUS. Although this model slightly underestimates the saturation moisture absorption rate due to the omission of edge effect, it still accurately reflects the actual moisture absorption process of CFRP. Subsequently, the moisture absorption behavior of CFRP with varying thicknesses was analyzed, revealing that thinner CFRP specimens absorb moisture more rapidly, while thicker specimens exhibit slower absorption rates. Additionally, it was found that larger specific surface areas can induce edge effect, increasing the moisture diffusion coefficient in thickness direction and consequently raising the overall saturation moisture absorption rate. Finally, a CNN-LSTM deep learning model was developed to predict the moisture absorption behavior of CFRP. CNN-LSTM model demonstrated excellent predictive accuracy with significantly lower mean squared error (MSE = 8.48 × 10 −7 ) compared to traditional models (Langmuir: 1.09 × 10 −5 , FE: 5.22 × 10 −6 ), showing its superior capability in capturing complex nonlinear behavior and strong generalization potential. This study provides a novel approach for assessing the service life of CFRP in complex environments.

The Exoplanet Edge: Planets Do Not Induce Observable Transit Timing Variations with a Dominant Transit Timing Variation Period Faster than Half Their Orbital Period

Abstract Transit timing variations (TTVs) are observed for exoplanets at a range of amplitudes and periods, yielding an ostensibly degenerate forest of possible explanations. We offer some clarity in this forest, showing that systems with a distant perturbing planet preferentially show TTVs with a dominant period equal to either the perturbing planet’s period or half the perturbing planet’s period. We demonstrate that planet-induced TTVs are not expected with dominant TTV periods below this exoplanet edge (lower period limit) and that systems with TTVs that fall below this limit likely contain additional mass in the system. We present an explanation for both of these periods, showing that both aliasing of the conjunction-induced synodic period and the near 1:2 resonance superperiod and tidal effects induce TTVs at periods equal to either the perturber’s orbit or half-orbit. We provide three examples of known systems for which the recovered TTV period induced by a distant perturbing planet is equal to the perturber’s orbital period or half its orbital period. We then investigate Kepler two-planet systems with TTVs and identify 13 two-planet systems with TTVs below this TTV period lower limit, thus potentially uncovering the gravitational influence of new planets and/or moons. We conclude by discussing how the exoplanet edge effects can be used to predict the presence of distant companion planets in situations where TTVs are detected and where nearby companions can be ruled out by additional observations, such as radial velocity data.

Predicting Spatial Distributions of Mammalian Predation on Translocated Wild Turkeys in Agriculturally Dominated Landscapes

ABSTRACTTranslocating prey into unfamiliar environments may alter predator‐prey interactions on space utilization, making prey more vulnerable to predation. We predicted that the greater the edge density of cropland and developed land, the higher the probability of mammalian predation for translocated wild turkeys in the agriculturally dominated landscape of Quitman County in the northcentral Mississippi Alluvial Valley, USA. We radio‐tracked translocated wild turkeys using transmitters equipped with mortality sensors from January 2009 to July 2010. We applied multivariate ordinations and one‐class support vector machines to predict the spatial probabilities and locations of mammalian predation on translocated wild turkeys with data on kill locations and habitat edge densities. Mammalian predation was positively associated with crop field edge density, with kill‐location patches constituting about 6% of the study area. Our findings suggest that mammalian predation can decrease the success of wild turkey translocation in unfamiliar, agricultural‐dominant habitats.

Planted seedling regeneration using gap-based silviculture without herbicide in a wildfire-impacted forest of the Sierra Nevada

Abstract Gap-based silviculture, which we define as the creation and maintenance of multi-aged stands through the periodic harvesting of discrete canopy gaps, provides a potential mechanism for converting previously high-graded stands into more heterogeneous, multi-aged structures. An advantage of small canopy gaps, relative to even-aged regeneration methods, is their potential to suppress shrub competition while allowing seedling growth without the use of herbicides or other means of managing shrub competition. While this idea has been proposed in principle, it has not been tested. The objective of this study was to evaluate the use of small canopy gaps, which were 0.08 ha in size with a mean ratio of gap diameter to border tree height of 1.3, as a method to regenerate four mixed-conifer tree species. Gaps were randomly treated either with or without herbicide in a Sierra Nevada mixed-conifer forest. Our hypothesis was that, if this opening size provided sufficient edge effect to control shrub competition, there would be no or little difference in seedling growth between herbicide-treated and control gaps. For all species planted, height and basal diameter growth trends over time were very similar between gaps treated with and without herbicide. The similarity in seedling growth occurred despite a substantial difference in shrub cover between untreated (43%) and treated gaps (3%). We interpret this as evidence that a gap structure such as the one tested can allow a co-occurrence of mediated shrub development and seedling recruitment and that the primary limitation on seedling growth comes from overstory trees, not shrubs. We demonstrate an example of the difference in seedling growth that can be expected between small gaps and clearcuts in order to discuss tradeoffs between these silvicultural systems. Following repeated measurements of seedlings for 7 years following planting, a wildfire burned across the study area, allowing for an additional assessment of wildfire-related seedling damage and mortality in gaps with differing levels of shrub abundance. Substantial mortality of study trees occurred following wildfire (62% mortality 1-year post-fire), but mortality was similar between treated and control gaps. This suggests that shrubs do not have a negative impact with respect to fire related mortality in small canopy gaps despite higher shrub cover. Gap-based silviculture could be a valuable tool for developing multi-aged, multi-species stands without the use of herbicide.

Edge-Mediated Magnetic Domain Rearrangement in van der Waals Magnet Fe3GaTe2.

The emergence of van der Waals (vdW) magnets has opened new frontiers for investigation of 2-dimensional magnetism and application of spintronic memories. However, as the system approached the nanoscale, the edge effect significantly enhanced, posing critical challenges in understanding edge-mediated modifications of magnetic behavior, such as the nanoscale magnetic domain. Here, we employ magnetic force microscopy to systematically investigate edge-mediated magnetic domain rearrangement in Fe3GaTe2 flakes. By performing thermal treatment, we observed a distinct transition from labyrinthine to edge-localized stripe domains perpendicular to the flake edges. Furthermore, we reveal a competition and stabilization between size effect and edge effect by investigating thickness-dependent variation in the length of stripe domains and indicate that such an edge effect suppresses the formation of skyrmions. These findings not only elucidate the critical role of the edge effect in governing the domain morphology of vdW magnets but also provide insights for designing edge-mediated nanostructures in next-generation spintronic devices.

Monitoring and analysis of land cover changes in Yala National Park, Sri Lanka using Landsat time series (2000∼2022)

ABSTRACT Yala National Park (YNP), a biodiversity hotspot in South Asia, is increasingly threatened by human-induced landscape transformation. However, long-term assessments of land cover dynamics and landscape integrity remain limited. This study, grounded in a landscape ecology – remote sensing framework, leverages 23 years of Landsat time-series data on Google Earth Engine (GEE) to quantify habitat loss and analyze landscape changes in YNP. The results reveal the following over a 23-year period: (i) YNP shows mild fragmentation characteristics, primarily manifested as local forest loss and patchiness of land cover under increased edge effects (0.7% decline in Contagion Index); (ii) The buffer zone has experienced high-intensity land cover conversion (with agricultural land accounting for 29.9% in 2022) and fragmentation of landscape patterns (13.7% decline in Contagion Index), with agricultural expansion infiltrating towards the edges of YNP; (iii) The increase in cropland area shows a significant positive correlation with the number of fatalities caused by Human-elephant conflict (Pearson's, r = 0.92, p < 0.01). Our study demonstrates the monitoring and assessment of long-term landscape changes, providing practical guidance for national parks facing similar human-wildlife conflict challenges.

Thermal Curing of Adhesive Joints Enabled by Precision Heating Multi-Material Additive Manufacturing

This study explores the development of adhesive joints incorporating embedded resistive heating elements, fabricated using Multi-Material Additive Manufacturing. By embedding conductive circuits within the adherends, localized heating enables controlled curing of the adhesive, optimizing its mechanical properties according to the specific application. This study focused on modifying the stiffness of the adhesive in order to reduce edge effects in the joints and allow for better load distribution. The adherends were made of PLA, the resistive heating elements were fabricated using carbon black-filled conductive PLA, and an epoxy resin served as the adhesive. Thermal and mechanical characterizations were conducted, evaluating the effects of different curing temperatures on joint strength. The tensile strength for joints cured at 120 °C exhibited a 58% increase in maximum breaking force and a 144% increase in elongation at break compared to the joints cured at room temperature. These findings highlight the potential of AM-integrated resistive heating for precise adhesive curing, enabling the local tailoring of the adhesive stiffness in the overlap volume.

Hierarchical Surface Textures for Improved Coating Durability Using Double-Sided Incremental Forming

Abstract This study investigates the impact of surface texturing on the durability of Slippery Liquid-Infused Porous Surfaces (SLIPS) coatings applied to sheet metal substrates by the Double-Sided Incremental Forming (DSIF) process. Toolmarks generated during the DSIF process were leveraged as an efficient method for texturing, enabling both the formation and texturing of surfaces using a single set of universal tools. The effects of texture patterns, spacing, and tool movement on SLIPS performance were evaluated by comparing samples generated in the presence and absence of tool spinning/rotation. The results indicate that textures with dimple patterns significantly improve coating durability by acting as lubricant reservoirs, reducing oil depletion, and supporting self-healing. In contrast, continuous grooves were less effective due to limited capillary action and increased edge effects. Tool spinning further enhanced surface topography, producing an undulating texture that minimized contact line pinning and improved surface hydrophobicity. Low-speed spinning (approximately 10 rpm) facilitated a transition to mixed sliding-rolling friction, resulting in smoother textures and extended coating durability. Combining dimple patterns and controlled spinning provides a synergistic approach for optimizing SLIPS coatings, offering a practical solution for enhancing durability without requiring additional equipment. This study underscores the potential of controlled texturing and tool movement to improve SLIPS efficacy and broaden its applications in industrial, clinical, and consumer environments.