Patch Height Research Articles

Pore-scale study on shear rheology of wet granular materials

We study pore-scale rheological phenomena in two-dimensional sheared wet granular materials. Simulations use a coupled cascaded lattice Boltzmann and discrete element method, to model the liquid–gas multiphase flows and multiple-solid-particle dynamics, respectively. The wet granular material is prepared by first filling a rectangular domain with solid particles and then partially filling the pores between the particles with the liquid phase. The material is then sheared based on standard Couette flow configuration, i.e., with lid-driven velocities U and -U on the top and bottom walls, respectively. The simulations show that the apparent viscosity of the system attains a minimum when the material is wet but not fully saturated, i.e., at a saturation of ∼0.10. Such an observation is coherent both for materials composed of monodisperse and polydisperse particles. Interestingly, this observation coincides with the experimental finding of the decrease in sliding friction on sand by adding a small amount of water. The underlying mechanism is elucidated based on the pore-scale study of liquid patch dynamics. It is shown that, with increasing liquid saturation, the rheology of the wet granular materials is affected by two competing effects: (i) a larger number of liquid patches appear leading to fluidization of the system and (ii) larger patches are formed, clogging the flow. The minimum apparent viscosity saturation of ∼0.10 coincides with the maximum of the product of the two factors: the number of liquid patches and ratio between the system height and largest patch height.

Shaping Baltimore’s urban forests: past insights for present-day ecology

ContextLand use history of urban forests impacts present-day soil structure, vegetation, and ecosystem function, yet is rarely documented in a way accessible to planners and land managers.ObjectivesTo (1) summarize historical land cover of present-day forest patches in Baltimore, MD, USA across land ownership categories and (2) determine whether social-ecological characteristics vary by historical land cover trajectory.MethodsUsing land cover classification derived from 1927 and 1953 aerial imagery, we summarized present-day forest cover by three land cover sequence classes: (1) Persistent forest that has remained forested since 1927, (2) Successional forest previously cleared for non-forest vegetation (including agriculture) that has since reforested, or (3) Converted forest that has regrown on previously developed areas. We then assessed present-day ownership and average canopy height of forest patches by land cover sequence class.ResultsMore than half of Baltimore City’s forest has persisted since at least 1927, 72% since 1953. About 30% has succeeded from non-forest vegetation during the past century, while 15% has reverted from previous development. A large proportion of forest converted from previous development is currently privately owned, whereas persistent and successional forest are more likely municipally-owned. Successional forest occurred on larger average parcels with the fewest number of distinct property owners per patch. Average tree canopy height was significantly greater in patches of persistent forest (mean = 18.1 m) compared to canopy height in successional and converted forest patches (16.6 m and 16.9 m, respectively).ConclusionsHistorical context is often absent from urban landscape ecology but provides information that can inform management approaches and conservation priorities with limited resources for sustaining urban natural resources. Using historical landscape analysis, urban forest patches could be further prioritized for protection by their age class and associated ecosystem characteristics.

DNA Sensing Platforms: Novel Insights into Molecular Grafting Using Low Perturbative AFM Imaging.

By using AFM as a nanografting tool, we grafted micrometer-sized DNA platforms into inert alkanethiol SAMs. Tuning the grafting conditions (surface density of grafting lines and scan rate) allowed us to tailor the molecular density of the DNA platforms. Following the nanografting process, AFM was operated in the low perturbative Quantitative Imaging (QI) mode. The analysis of QI AFM images showed the coexistence of molecular domains of different heights, and thus different densities, within the grafted areas, which were not previously reported using contact AFM imaging. Thinner domains corresponded to low-density DNA regions characterized by loosely packed, randomly oriented DNA strands, while thicker domains corresponded to regions with more densely grafted DNA. Grafting with densely spaced and slow scans increased the size of the high-density domains, resulting in an overall increase in patch height. The structure of the grafted DNA was compared to self-assembled DNA, which was assessed through nanoshaving experiments. Exposing the DNA patches to the target sequence produced an increase in the patch height, indicating that hybridization was accomplished. The relative height increase of the DNA patches upon hybridization was higher in the case of lower density patches due to hybridization leading to a larger molecular reorganization. Low density DNA patches were therefore the most suitable for targeting oligonucleotide sequences.

Dingo Optimizer Plus Black Widow Optimization-Based Optimal Design of Multiband U-Slot Microstrip Patch Antenna

Currently, for high-performance appliances the easiness of installation, weight, size, and cost are major constraints. Spacecraft, aircraft, missile, and satellite appliances require lower profile antennas, and U-slot MPA can be well fitted for such appliances because of its wide-band nature. MPA integrating U-shape slots are renowned for including comparatively larger bandwidth impedance (around 30%). This article aims to develop an optimized U-slot MPA design, where the antenna measurements such as patch height or board thickness, patch length, patch width, and feed diameter are optimally tuned by a new hybrid optimization model. As the concepts of Dingo Optimization and Black Widow Optimization are combined, the adopted algorithm is called Black Widow in Dingo Model with Logistic Chaotic Map. The priority of the introduced scheme is examined via the assessment over existing models by varying the frequency ranges, and cost analysis is also done for varied iterations.

Hybrid optimization model for design and optimization of microstrip patch antenna

AbstractThe antenna design for a specified resonant frequency necessitates the computation of optimal values of different sizes. This is a harder task for microstrip patch antenna (MPA) since there is no precise numerical formula that leads to accurate solutions for designing these antennas. Presently, bio‐inspired approaches are widely deployed in numerous antenna designs and it has revealed an immense assurance in handling the rising necessities of antenna engineering for overall cost, reduced size, and enhanced performances. This work aims to introduce an optimal MPA design, where the antenna elements like patch length, patch height, substrate width, and substrate length are optimally tuned by a new hybrid optimization model. For this, a new hybridized model known as shark smell integrated EHO is proposed. Eventually, the primacy of the suggested model is scrutinized via varied assessments.

WRITER IDENTIFICATION: THE EFFECT OF IMAGE RESIZING ON CNN PERFORMANCE

Abstract. Introducing Deep Learning has been successful in improving the performance of automated writer identification systems. However, using very large patch sizes as input to CNN consumes a lot of machine resources and requires a lot of training time. To overcome this problem, many researchers use resized images.In this paper, we will try to make a comparative study between several patches sizes which were then resized to a normalized size of 32 × 32. Our aim is to elaborate the best recommendations for choosing the image resizing in order to increase the CNN performance. Thus, we will carry our tests on three databases. The first is CVL, a Latin dataset with 310 writers, the second is CERUG-CH a Chinese dataset with 105 writers and the last is KHATT that contains the Arabic writings of 1000 writers. To see if the type of CNN model impacts the results conducted on resized images, we deploy two models: ResNet-18 and MobileNet. The main finding is that the best results correspond to the resizing values of the images which makes it possible to have the average line height of the writings closer to the height of the CNN patches.

Physical structure and biological composition of canopies in tropical secondary and old-growth forests.

The area of tropical secondary forests is increasing rapidly, but data on the physical and biological structure of the canopies of these forests are limited. To obtain such data and to measure the ontogeny of canopy structure during tropical rainforest succession, we studied patch-scale (5 m2) canopy structure in three areas of 18–36 year-old secondary forest in Costa Rica, and compared the results to data from old-growth forest at the same site. All stands were sampled with a stratified random design with complete harvest from ground level to the top of the canopy from a modular portable tower. All canopies were organized into distinct high- and low-leaf-density layers (strata), and multiple strata developed quickly with increasing patch height. The relation of total Leaf Area Index (LAI, leaf area per area of ground) to patch canopy height, the existence of distinct high and low leaf- density layers (strata and free air spaces), the depth and LAI of the canopy strata and free air spaces, and the relation of the number of strata to patch canopy height were remarkably constant across the entire successional gradient. Trees were the most important contributor to LAI at all stages, while contribution of palm LAI increased through succession. We hypothesize that canopy physical structure at the patch scale is driven by light competition and discuss how this hypothesis could be tested. That canopy physical structure was relatively independent of the identity of the species present suggests that canopy physical structure may be conserved even as canopy floristics shift due to changing climate.

Design of novel super wide band antenna close to the fundamental dimension limit theory

This paper investigates the design and practical implementation of a Super Wide Band (SWB) antenna along with the application of fundamental bandwidth limitation theory of small antennas in the proposed design. The antenna is designed on a material with permittivity, εr = 3 where the patch metallization height is maintained as 0.035 mm. The designed antenna is then modified by enhancing the copper patch with an additional layer of 28.5 mm thickness. The proposed antenna achieves a huge frequency range with a ratio bandwidth starting from 96.96:1 to as high as 115.10: 1. The designed antenna operating band with thinner height starts from 1.65 to 160 GHz while with the added patch metallic height, the antenna operates from a minimum of 1.39 to 160 GHz with an average nominal bandwidth of more than 158 GHz. By enhancing the patch height, the antenna spherical volume is utilized more efficiently. Using this principle, the antenna impedance bandwidth is augmented while a reduction in electrical size is achieved. A comparison with the fundamental theories by Chu and Mclean illustrates that the designed SWB antenna electrical size exceeds Mclean and nearly touches the Chu fundamental limit curve. This eventually offers the maximized bandwidth with the most compact size for an SWB antenna. The designed antenna with thinner patch metallization height is practically fabricated and measured up to 67 GHz using Vector Network Analyzer to provide experimental validation.

Allometric equations for the invasive vine air potato (Dioscorea bulbifera) in its exotic range in Florida

AbstractNondestructive means for estimating air potato (also known as air yam; Dioscorea bulbifera L.) biomass will help gauge its management efficacy over time. We developed allometric equations to estimate total and fractional biomass components and densities of aerial bulbils and underground tubers of field-grown D. bulbifera in Florida. We selected four naturally infested sites representing its southern, central, and northern distribution in Florida and measured three independent variables (vine densities, stem diameters, and top heights) of 84 (21 site−1) discrete D. bulbifera patches during late October to early December of 2012. We destructively harvested D. bulbifera biomass, sorted by tubers, stems, leaves, and bulbils; counted units of bulbils and underground tubers (dependent variables); and dried to a constant weight. Mean percentages of tuber, stem, leaf, and bulbil fractions in total biomass were 42.0, 15.6, 26.0, and 16.4, respectively. We developed a parameterized multiplicative prediction model and regression equation for each dependent variable. Slopes of relationships among independent and dependent variables varied by biomass and density (bulbil and tuber) of plant components. Multiplied values of independent variables: all three for total, tuber, stem, and leaf biomass; two (vine base diameter*patch height) for bulbil biomass; two (vine density*patch height) for bulbil density; and only one (stem density) for tuber density provided best (R2-based) prediction values. These models will provide nondestructive methods for estimating biomass components and density of vegetative propagules of naturally growing D. bulbifera. Models are critical for understanding the performance of D. bulbifera in its exotic range, estimating biomass to project control costs, and comparing biomass components and bulbil/tuber densities during pre- and postmanagement periods to gauge control efficacy.

Allometric relationships for selected macrophytes of kettle holes in northeast Germany as a basis for efficient biomass estimation using unmanned aerial systems (UAS)

Quantifying plant biomass in ecosystems is an essential basis for many ecological questions. A direct estimation of macrophyte biomass proves to be difficult for the large number of kettle holes in Pleistocene landscapes, due to their strong heterogeneities. This study compared a classical non-destructive method for biomass estimation based on allometric relationships built from a larger selection of plant trait variables with regressions only based on plant height and cover of four macrophyte species typical for kettle holes in northeast Germany (i.e. Carex riparia, Phalaris arundinacea, Persicaria amphibia, Rorippa amphibia). Their predictive power and potential applicability for remotely sensed biomass estimation using unmanned aerial systems (UAS) was evaluated. The usage of several in-situ measured plant traits of individual plants revealed best macrophyte biomass predictions (R² = 0.84 to 0.95). Yet, using only plant height and cover to predict biomass still showed a moderate to good correlation (R² = 0.52 to 0.81). Using P. arundinacea as an example, we demonstrated for one kettle hole the potential of calculating plant patch height from digital surface models (DSM) derived from UAS RGB images processed with structure-from-motion (SfM) photogrammetry. After applying a site-specific correction factor for discrepancies between reference field measurements of plant heights and DSM derived plant heights, we were able to calculate P. arundinacea biomass of the entire kettle hole based on allometric relationships using plant height and cover. Finally, we briefly discuss how further methodological development can improve UAS-derived plant height as predictor variable for biomass estimation.

Spatial patch structure and adaptive strategy for desert shrub of Reaumuria soongorica in arid ecosystem of the Heihe River Basin

In many arid ecosystems, vegetation frequently occurs in high-cover patches interspersed in a matrix of low plant cover. However, theoretical explanations for shrub patch pattern dynamics along climate gradients remain unclear on a large scale. This context aimed to assess the variance of the Reaumuria soongorica patch structure along the precipitation gradient and the factors that affect patch structure formation in the middle and lower Heihe River Basin (HRB). Field investigations on vegetation patterns and heterogeneity in soil properties were conducted during 2014 and 2015. The results showed that patch height, size and plant-to-patch distance were smaller in high precipitation habitats than in low precipitation sites. Climate, soil and vegetation explained 82.5% of the variance in patch structure. Spatially, R. soongorica shifted from a clumped to a random pattern on the landscape towards the MAP gradient, and heterogeneity in the surface soil properties (the ratio of biological soil crust (BSC) to bare gravels (BG)) determined the R. soongorica population distribution pattern in the middle and lower HRB. A conceptual model, which integrated water availability and plant facilitation and competition effects, was revealed that R. soongorica changed from a flexible water use strategy in high precipitation regions to a consistent water use strategy in low precipitation areas. Our study provides a comprehensive quantification of the variance in shrub patch structure along a precipitation gradient and may improve our understanding of vegetation pattern dynamics in the Gobi Desert under future climate change.

Flexural Rigidity and Shoot Reconfiguration Determine Wake Length Behind Saltmarsh Vegetation Patches

AbstractVegetation patches play an important role in controlling sediment deposition in shallow aquatic environments such as coastal saltmarshes and fluvial systems. However, predicting deposition around vegetation patches is difficult due to the complexity of patch morphology and their dynamic interaction with the flow. Here we incorporate a biomechanical model, parameterized using field data, within a 3‐D computational fluid dynamics model which allows prediction of individual shoot reconfiguration within patches due to flow forcing. The model predicts velocity attenuation and bed shear stresses within the wake of the patch which agree spatially with accretion patterns measured in the field using terrestrial lidar. The model is applied to sparse patches of Suaeda maritima, located in saltmarshes of coastal habitats, to explore the role of (I) shoot distribution, (II) patch geometry, (III) shoot flexural rigidity, and (IV) bulk flow velocity in determining the length of the predicted wake region. We demonstrate that for Suaeda maritima, with intermediate rigidity, the vertical shear layer over the vegetation controls the length of the predicted wake region. Consequently, reconfiguration due to flexural rigidity strongly impacts on wake length, confounding the relationship between patch height and wake length. A simplified model for predicting wake length based on shoot reconfiguration is applied to the simulation data and shows good agreement. The results demonstrate that the observed wake characteristics can be well explained by intraspecific variability in flexural rigidity, thus demonstrating the importance of biomechanical traits in determining flow‐vegetation‐sediment interactions.

Analyzing Spatial Distribution Patterns of European Beech (Fagus sylvatica L.) Regeneration in Dependence of Canopy Openings

The use of natural regeneration techniques is one of the key elements of modern (close-to-nature) forestry. In natural forests, changes in canopy cover, such as the emergence and successive re-closure of canopy gaps are particularly important, as they influence the light availability on the forest floor. Creating canopy gaps of different size is a promising silvicultural tool allowing the regulation of the light availability in managed forests in order to control regeneration composition and development. In this study, we used terrestrial laser scanning data to investigate the relationship between canopy-gap dimensions and emerging natural regeneration along a gradient of management in forests dominated by European beech (Fagus sylvatica, L.). We analyzed the spatial distribution and height of regeneration patches in dependence of gap characteristics. Mean regeneration height decreases progressively from the gap polygon over a transition zone towards the area under the canopy, while the tallest regeneration plants were placed in positions midway between center and gap edge, and not directly in the gap center as we initially assumed. The centers of regeneration patches were not displaced when compared to the associated canopy gap centers, as has been reported in other studies conducted on the northern hemisphere for various tree species. The observed patterns did not depend on management strategies, indicating that regeneration responded equally to naturally created gaps and gaps that were caused by logging. We conclude that establishment and development of shade-tolerant European beech regeneration in forest stands is driven by gap openings, but not necessarily direct radiation. If at all, pronounced direct radiation mainly occurs at the northern edge of large gaps. Neither regeneration patch center, nor regeneration tree height pointed in that direction. Our study suggests that in the investigated beech-dominated forests the effect of increased light availability at the northern edge of a gap is overruled by other factors increasing towards the gap edge, such as increased belowground competition of the overstory trees.

Tapered Antenna Array with Non-identical Triangular MSA Elements for FSLL Reduction

Reduced interference from nearby communication systems is an essential need in all generations of wireless communication systems. In this paper, interference is reduced by reducing the first side lobe level (FSLL) by using the concept of tapering realized with non-identical triangular elements. Resonance frequency of an Equilateral triangular microstrip antenna depends on its patch height. This property has been used effectively to realize isosceles triangular microstrip antenna with equal height, thus resonating at the same frequency. The isosceles triangular elements are designed as non-identical elements, based on its area reduction and hence gain variation, with respect to three different standard amplitude distribution functions. Six such arrays have been designed with two different inset notch feed gaps. An analysis of the non-identical elements’ antenna arrays with varying inset notch feed gaps to realize tapering in the H-plane for FSLL reduction has been presented. To verify the proposed concept, one triangular patch array using eight non-identical equilateral and isosceles triangular elements designed at 6 GHz is fabricated and tested. A reasonably acceptable agreement between the simulated and measured results validates the proposed concept.

When less is more: heterogeneity in grass patch height supports herbivores in counter-intuitive ways

Herbivores are an integral part of the African landscape and have evolved with the vegetation to create the savanna landscape. Managers of these landscapes can benefit from a better understanding of how indigenous herbivores use the landscape to which they are adapted. In this study we observed which patches were frequently utilised, by doing regular monthly road counts, grass height observations and dung counts on selected short grass patches in the Kruger National Park. Smaller-framed impala and blue wildebeest (meso-herbivores) were most regularly seen on these nutritious patches, while from dung deposits it was clear that the even larger-framed buffalo (mega-herbivores) spent time there. This preference can be explained by considering the nutritional needs and food intake of the herbivores. Smaller-framed herbivores seem to be able to satisfy their dietary requirements on the high-quality forage patches, while larger-framed herbivores seem to supplement the quality forage by also spending foraging time on areas of higher grass biomass. From this insight we propose that range management should take herbivore preferences into account and allow herbivores to select and concentrate their foraging on the most nutritious forage. This approach is likely to decrease inputs while allowing animals to maintain or increase production.

Ecological consequences of shrub encroachment in the grasslands of northern China

Shrub encroachment is a critical environmental issue in arid and semi-arid landscapes. However, due to the complicated effects of shrub characteristics and environmental variables, ecological consequences of shrub encroachment significantly differ in different regions. As a result, although the phenomenon of shrub encroachment is widespread in the grasslands of northern China, its ecological consequences and associated drivers have not been well documented at the regional scale. We explored the effects of shrub encroachment on ecosystem structures (herb richness and abundance) and functioning (above- and belowground biomass, and soil carbon and nitrogen content) and evaluated the relative importance of climatic variables (temperature and precipitation) and shrub characteristics (cover, area, and height) as drivers of these effects. Based on field data from 53 sites that stretch across approximately 3000 km in northern China, we conducted the relative interaction intensity (RII) of the response variables between shrub patches and grassy matrix, and then used the structural equation modeling (SEM) to assess the relative importance of chosen drivers on the ecological consequences. Shrub encroachment increased the landscape heterogeneity by decreasing the richness, abundance and aboveground biomass of herbs, while by increasing the soil carbon and nitrogen content. The SEM explained 25–43% of the variation in shrub characteristics and 5–34% of the variation in the effects of shrub encroachment. Shrub height had greater effects on the RII of herb richness, soil carbon and soil nitrogen content, and the standardized total effects were 0.48, 0.25 and 0.18, respectively. Precipitation and temperature positively affected the impacts of shrub encroachment on herb richness, abundance, biomass, and multi-indexes. However, the direct effects of climate could be partially mediated by indirect effects via shrub characteristics. The height, size and cover of shrub patches significantly influenced the community structures and functioning of grassland ecosystems. The increasing aridity could potentially exacerbate the negative consequences of shrub encroachment in arid regions. Our results also demonstrated that the effects of climate variables on grassland ecosystems could be mediated by shrub management.

Feedbacks of flow and bed morphology from a submerged dense vegetation patch without upstream sediment supply

Laboratory experiments were performed to investigate how flow patterns and bed morphology are affected around a submerged vegetation patch in the condition without an upstream sediment supply. Five patches with different submergences, including four submerged patches and one emergent patch, were considered. In all cases, a wake region with depressed velocity and turbulent kinetic energy (TKE) occurred directly behind the vegetation patches. Beyond the end of the wake region, the presence of Karman vortices contributed to the recovery of the velocity and the peak of the TKE. However, a distinct von Karman vortex street was present at the ratio h/D > 1 with patch height h and diameter D, and the ratio was not influenced by the change in the channel bed. Because of the presence of stem-scale turbulence, net erosion was observed inside the patch in all cases. The motion of the colored sediment (placed inside the patch) indicated that the sediment inside the patch moved downstream and deposited in the patch wake. For a deeply submerged patch, a net deposition region was observed in the patch wake. For slightly submerged and emergent patches, a net erosion region was observed in both the patch wake and the adjacent region. Although the sand inside the patch was transported in the wake, the degree of net deposition was smaller than the degree of net erosion, which caused significant bed erosion. The greatest net erosion in the adjacent region was related to both the submergence (h/H) and the solid volume fraction (φ) of the patch. A greater h/H and φ resulted in a higher maximum net erosion value.

Load carrying capacity of ice-strengthened frames under idealized ice load and boundary conditions

Overload response of the stiffening frames in ship side structure due to ice loading is an important design consideration for ships operating in ice infested waters. By overload, we mean loads that are larger than assumed by the rules. Therefore, the response of ice strengthened grillage frames is investigated under a range of idealized rectangular pressure patches and by assuming different boundary conditions for the structural units. A flat, representative grillage of an ice-strengthened ship is considered and analysed using non-linear Finite Element Method. The response of the grillage frames is compared with the isolated frame response. Two frame types are considered: flatbars and L-frames. Finite element simulations revealed that patch length has strong effect on the frame deformation mode. The key characteristic that differentiates the response under shorter and longer patches is the longitudinal membrane stretching of the shell plating. Longer patches tend to suppress this deformation mode that leads to similar frame behaviour observed in isolated frame analysis. It is further shown that overload capacity of grillage frames reduces with increasing patch length to levels observed in isolated frame analysis. Analysis of plastic strain development in the frames and plating revealed that plastic strain localized faster in frames, but shell plating is more sensitive to patch height variations. This renders frames more susceptible to fracture than plating. Finally, the local failure mechanisms of the L-frames tend to diminish the load sharing capability and so negatively affects the overload behaviour.

Sensitivity of Modeled Channel Hydraulic Variables to Invasive and Native Riparian Vegetation

Quantifying the roughness of riparian vegetation is important where it plays a dominant role by reducing water velocity. Vegetation roughness was calculated based on the plant characteristics of three dominant herbaceous plants, including one invasive, along the Sprague River, Oregon. E. palustris and invasive P. arundinacea exhibit higher and similar roughness values whereas C. vesicaria is lower. To determine differences, hydraulic channel conditions were modeled within NAYS 2DH. First, current conditions were modeled by populating the channel banks with roughness, plant density, and height of vegetation patches. Next, along the same reach, monocultures were modeled assuming dominance of individual species. In comparing the two native species to the invasive species, monoculture conditions show that plant density and roughness causes the native E. palustris to have the highest ability to decrease stream velocity. In areas where the invasive species is outcompeting E. palustris, such changes could cause increases in velocity and less stable bank surfaces.

Spaceborne potential for examining taiga-tundra ecotone form and vulnerability.

In the taiga-tundra ecotone (TTE), site-dependent forest structure characteristics can influence the subtle and heterogeneous structural changes that occur across the broad circumpolar extent. Such changes may be related to ecotone form, described by the horizontal and vertical patterns of forest structure (e.g., tree cover, density and height) within TTE forest patches, driven by local site conditions, and linked to ecotone dynamics. The unique circumstance of subtle, variable and widespread vegetation change warrants the application of spaceborne data including high-resolution (< 5m) spaceborne imagery (HRSI) across broad scales for examining TTE form and predicting dynamics. This study analyzes forest structure at the patch-scale in the TTE to provide a means to examine both vertical and horizontal components of ecotone form. We demonstrate the potential of spaceborne data for integrating forest height and density to assess TTE form at the scale of forest patches across the circumpolar biome by (1) mapping forest patches in study sites along the TTE in northern Siberia with a multi-resolution suite of spaceborne data, and (2) examining the uncertainty of forest patch height from this suite of data across sites of primarily diffuse TTE forms. Results demonstrate the opportunities for improving patch-scale spaceborne estimates of forest height, the vertical component of TTE form, with HRSI. The distribution of relative maximum height uncertainty based on prediction intervals is centered at ~40%, constraining the use of height for discerning differences in forest patches. We discuss this uncertainty in light of a conceptual model of general ecotone forms, and highlight how the uncertainty of spaceborne estimates of height can contribute to the uncertainty in identifying TTE forms. A focus on reducing the uncertainty of height estimates in forest patches may improve depiction of TTE form, which may help explain variable forest responses in the TTE to climate change and the vulnerability of portions of the TTE to forest structure change.