scholarly journals Multiscale Organization of Landscape Structure in the Middle Taiga of European Russia

2019 ◽  
Vol 66 ◽  
pp. 1-19 ◽  
Author(s):  
Alexander V. Khoroshev
Keyword(s):  
Spatial Heterogeneity ◽  
Landscape Structure ◽  
Higher Order ◽  
Hierarchical Organization ◽  
European Russia ◽  
Morphological Properties ◽  
Middle Taiga ◽  
Hierarchical Level ◽  
Response Surface Regression ◽  
Landscape Ecological

Dominant landscape-ecological models either focus on the hierarchical organization of a single phenomenon or describe relations at a single hierarchical level. We proposed the tool MALS (Multiscale Analysis of Landscape Structure) to reveal  multiple independent hierarchies based on the interactions between properties of relief, soils and vegetation and tested it on the example of the middle-taiga landscape in European Russia. Morphological properties of soils and abundance of plant species were measured in operational territorial units. Multidimensional scaling was used to reveal ecological drivers. Combinations of landforms from DEM were used to describe spatial heterogeneity in the higher-order geosystems. Response surface regression was applied to relate soils and vegetation to each other and to relief of several hypothetic higher-order geosystems. Spatial extent of a higher-order geosystem was determined from the series of equations. Then we compared contributions of external (inter-level) and internal (intra-level) interactions to spatial variability of soils and vegetation. Herbs, low shrubs, and morphologic soil properties turned out to be controlled mainly by the geosystems with the linear size 1200 m, while trees, shrubs, and sediments – by the geosystems with size 2000 m. From 2 to 5 levels of the higher-order geosystems should be considered in order to obtain the proper explanation of spatial heterogeneity.

scholarly journals Environmental differences of land creation in time interval for determination of industrial influence on landscape

2017 ◽  
Keyword(s):  
Land Cover ◽  
Landscape Structure ◽  
Time Horizon ◽  
Hierarchical Level ◽  
Time Interval ◽  
Topographic Map ◽  
Ecological Stability ◽  
The Sustainable Development ◽  
Landscape Ecological

The assessment of the spatial structure the land cover has great significance for the research of landscape especially from the aspect of the maintaining landscape ecological stability and the sustainable development as well as the landscape potential. At the same time it has an important role in identifying of impacts the industry on the landscape. The classes of land cover layers can be considered as the basis for other analyses of landscape. Purpose.: In the contribution we decided to compare the changes in landscape structure between the years 1958 - 2009 in territory of city Krompachy. Methods: field, analytical and mathematical. Results: For evaluating changes in the landscape structure we used topographic map from 1958 and orthophotomaps of the actual situation in 2009. The changes in the landscape structure were evaluated through GIS technologies in time horizon 1958 - 2009. Absolute and percentage differences in the land cover classes for the time horizon 1958 - 2009 are expressed by means of contingency tables transformation. The trends in the development classes of land cover are documented by the graph of the land cover classes on the second hierarchical level.

scholarly journals Hierarchical Organization of Corticothalamic Projections to the Pulvinar

2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Reza Abbas Farishta ◽  
Denis Boire ◽  
Christian Casanova
Keyword(s):  
Higher Order ◽  
Hierarchical Organization ◽  
Hierarchical Level ◽  
Thalamic Nuclei ◽  
Cortical Areas ◽  
Visual Areas ◽  
Cortical Hierarchy ◽  
Area 21A ◽  
Extrastriate Areas ◽  
Corticothalamic Projections

Abstract Signals from lower cortical visual areas travel to higher-order areas for further processing through cortico-cortical projections, organized in a hierarchical manner. These signals can also be transferred between cortical areas via alternative cortical transthalamic routes involving higher-order thalamic nuclei like the pulvinar. It is unknown whether the organization of transthalamic pathways may reflect the cortical hierarchy. Two axon terminal types have been identified in corticothalamic (CT) pathways: the types I (modulators) and II (drivers) characterized by thin axons with small terminals and by thick axons and large terminals, respectively. In cats, projections from V1 to the pulvinar complex comprise mainly type II terminals, whereas those from extrastriate areas include a combination of both terminals suggesting that the nature of CT terminals varies with the hierarchical order of visual areas. To test this hypothesis, distribution of CT terminals from area 21a was charted and compared with 3 other visual areas located at different hierarchical levels. Results demonstrate that the proportion of modulatory CT inputs increases along the hierarchical level of cortical areas. This organization of transthalamic pathways reflecting cortical hierarchy provides new and fundamental insights for the establishment of more accurate models of cortical signal processing along transthalamic cortical pathways.

scholarly journals Landscape Ecological Structure in the Eastern Part of the North Vidzeme Biosphere Reserve, Latvia

2008 ◽  
Vol 62 (1-2) ◽  
pp. 63-70
Author(s):  
Aivars Tērauds ◽  
Oļgerts Nikodemus ◽  
Inga Rasa ◽  
Simons Bells
Keyword(s):  
Land Use ◽  
Landscape Structure ◽  
Land Use Changes ◽  
Biosphere Reserve ◽  
Forest Area ◽  
Forest Patches ◽  
Ecological Structure ◽  
The North ◽  
Landscape Units ◽  
Landscape Ecological

Landscape Ecological Structure in the Eastern Part of the North Vidzeme Biosphere Reserve, Latvia Latvia is a country where the forest area has increased and habitat fragmentation has reversed compared with many other European countries. In order to examine the effect of this expansion on biodiversity, vegetation maps dating from 2002 and the years 1930-1936 were used for comparative landscape structure analyses while archive materials from forest plans, and data from the national forest management database were used for land use analysis. Four landscape ecoregions in the eastern side of the North Vidzeme Biosphere Reserve were selected for analysis. Landscape structure indicators derived from landscape ecology were used for the ecological assessment of land use changes. The total number of forest patches had decreased over the study period, but mean patch size had increased for all types of landscape element. This general change was found to vary between different landscape units in the study area. The biggest change in the area of forest patches occurred in the Rūjiena drumlin field, where the amount of forest patches decreased least and forest area increased the most. This study showed that the internal structure of the forest matrix changed substantially. This finding has implications for biodiversity protection if this trend of land use change continues.

Soil Formation in the Quarries after Forest Reclamation in the Middle Taiga Subzone of the Northeast of European Russia

2021 ◽  
Vol 54 (4) ◽  
pp. 631-647
Author(s):  
I. A. Likhanova ◽  
E. G. Kuznetsova ◽  
E. M. Lapteva ◽  
S. V. Deneva ◽  
B. A. Makeev
Keyword(s):  
Soil Formation ◽  
European Russia ◽  
Middle Taiga ◽  
Middle Taiga Subzone ◽  
Forest Reclamation

Landscape Heterogeneity and Dynamics

2019 ◽  
pp. 42-126
Author(s):  
Kimberly A. With
Keyword(s):  
Landscape Ecology ◽  
Spatial Heterogeneity ◽  
Landscape Structure ◽  
Landscape Heterogeneity ◽  
Spatial Scales ◽  
Anthropogenic Disturbances ◽  
Ecological Processes ◽  
Disturbance Dynamics ◽  
Wide Range ◽  
Over Time

Heterogeneity is a defining characteristic of landscapes and therefore central to the study of landscape ecology. Landscape ecology investigates what factors give rise to heterogeneity, how that heterogeneity is maintained or altered by natural and anthropogenic disturbances, and how heterogeneity ultimately influences ecological processes and flows across the landscape. Because heterogeneity is expressed across a wide range of spatial scales, the landscape perspective can be applied to address these sorts of questions at any level of ecological organization, and in aquatic and marine systems as well as terrestrial ones. Disturbances—both natural and anthropogenic—are a ubiquitous feature of any landscape, contributing to its structure and dynamics. Although the focus in landscape ecology is typically on spatial heterogeneity, disturbance dynamics produce changes in landscape structure over time as well as in space. Heterogeneity and disturbance dynamics are thus inextricably linked and are therefore covered together in this chapter.

scholarly journals Disease outbreak thresholds emerge from interactions between movement behavior, landscape structure, and epidemiology

2018 ◽  
Vol 115 (28) ◽  
pp. 7374-7379 ◽  
Author(s):  
Lauren A. White ◽  
James D. Forester ◽  
Meggan E. Craft
Keyword(s):  
Spatial Heterogeneity ◽  
Landscape Structure ◽  
Spatial Organization ◽  
Complex Disease ◽  
Animal Movement ◽  
Pathogen Transmission ◽  
Movement Behavior ◽  
Disease Dynamics ◽  
Conspecific Density ◽  
Pathogen Persistence

Disease models have provided conflicting evidence as to whether spatial heterogeneity promotes or impedes pathogen persistence. Moreover, there has been limited theoretical investigation into how animal movement behavior interacts with the spatial organization of resources (e.g., clustered, random, uniform) across a landscape to affect infectious disease dynamics. Importantly, spatial heterogeneity of resources can sometimes lead to nonlinear or counterintuitive outcomes depending on the host and pathogen system. There is a clear need to develop a general theoretical framework that could be used to create testable predictions for specific host–pathogen systems. Here, we develop an individual-based model integrated with movement ecology approaches to investigate how host movement behaviors interact with landscape heterogeneity (in the form of various levels of resource abundance and clustering) to affect pathogen dynamics. For most of the parameter space, our results support the counterintuitive idea that fragmentation promotes pathogen persistence, but this finding was largely dependent on perceptual range of the host, conspecific density, and recovery rate. For simulations with high conspecific density, slower recovery rates, and larger perceptual ranges, more complex disease dynamics emerged, and the most fragmented landscapes were not necessarily the most conducive to outbreaks or pathogen persistence. These results point to the importance of interactions between landscape structure, individual movement behavior, and pathogen transmission for predicting and understanding disease dynamics.

scholarly journals The frequency gradient of human resting-state brain oscillations follows cortical hierarchies

2019 ◽  
Author(s):  
Keyvan Mahjoory ◽  
Jan-Mathijs Schoffelen ◽  
Anne Keitel ◽  
Joachim Gross
Keyword(s):  
Cortical Thickness ◽  
Resting State ◽  
Brain Activity ◽  
Brain Area ◽  
Peak Frequency ◽  
Higher Order ◽  
Hierarchical Level ◽  
Spatial Gradient ◽  
Brain Oscillations ◽  
Posterior Anterior

AbstractThe human cortex is characterized by local morphological features such as cortical thickness, myelin content and gene expression that change along the posterior-anterior axis. We investigated if these structural gradients are associated with a similar gradient in a prominent feature of brain activity – namely the frequency of brain oscillations. In resting-state MEG recordings from healthy participants (N=187), we found that the strongest peak frequency in a brain area decreases significantly, gradually and robustly along the posterior-anterior axis following the global hierarchy from early sensory to higher-order areas. This spatial gradient of peak frequency was significantly anticorrelated with the cortical thickness of corresponding areas representing a proxy of the cortical hierarchical level. This result indicates that the intrinsic ‘resonance’ frequency decreases systematically from early sensory to higher-order areas and establishes a new structure-function relationship pertaining to brain oscillations as a core organizational principle that may underlie hierarchical specialization in the brain.

scholarly journals Canonical and noncanonical features of the mouse visual cortical hierarchy

2020 ◽  
Author(s):  
Rinaldo D. D’Souza ◽  
Quanxin Wang ◽  
Weiqing Ji ◽  
Andrew M. Meier ◽  
Henry Kennedy ◽  
...  
Keyword(s):  
Visual Cortex ◽  
Receptive Field ◽  
Active Vision ◽  
Structural Features ◽  
Hierarchical Organization ◽  
Hierarchical Level ◽  
Continuous Measure ◽  
Axonal Projections ◽  
Visual Cortical ◽  
Mouse Visual Cortex

ABSTRACTNeocortical circuit computations underlying active vision are performed by a distributed network of reciprocally connected, functionally specialized areas. Mouse visual cortex is a dense, hierarchically organized network, comprising subnetworks that form preferentially interconnected processing streams. To determine the detailed layout of the mouse visual hierarchy, laminar patterns formed by interareal axonal projections, originating in each of ten visual areas were analyzed. Reciprocally connected pairs of areas, and shared targets of pairs of source areas, exhibited structural features consistent with a hierarchical organization. Beta regression analyses, which estimated a continuous measure of hierarchical distance, indicated that the network comprises multiple hierarchies embedded within overlapping processing levels. Single unit recordings showed that within each processing stream, receptive field sizes typically increased with increasing hierarchical level; however, ventral stream areas showed overall larger receptive field diameters. Together, the results reveal canonical and noncanonical hierarchical network motifs in mouse visual cortex.

Classification of boreal forests in the North of European Russia. I. Oligotrophic coniferous forests

2007 ◽  
pp. 61-81 ◽  
Author(s):  
O. V. Morozova ◽  
L. B. Zaugolnova ◽  
L. G. Isaeva ◽  
V. A. Kostina
Keyword(s):  
Boreal Forests ◽  
Middle Part ◽  
Tree Canopy ◽  
European Russia ◽  
Pine Forests ◽  
Middle Taiga ◽  
Taiga Zone ◽  
Northern Forest ◽  
North West ◽  
The North

Results of a syntaxonomical study of the oligotrophic forests of northern European Russia are presented. The main forest types have been classified into 2 orders of the class Vaccinio-Piceetea, 4 alliances, 6 associations and 1 community. The new alliance Empetro-Piceion all. nov., which includes zonal spruce and birch northern forest association Empetro-Piceetum, has been established. These communities are formed according to cold temperature and high (sometimes temporarily) soil moisture and are characterized by the lower tree canopy, mosaic herb and moss-lichen layers with boreal mosses, sphagnum and lichens. In the middle taiga subzone these communities are replaced by Eu-Piceetum myrtilletosum. The forests with lichens are referred to order Cladonio-Vaccinietalia and divided into 4 associations. Lichen pine forests of the north-west of boreal zone were described as ass. Flavocetrario nivalis—Pinetum ass. nov. This association with a great number of lichens is differentiated by Cladonia arbuscula subsp. mitis, Flavocetraria nivalis, Cetraria ericetorum, Stereocaulon grande, Dicranum fuscescens, D. drummondii, Nephroma arcticum and species of Cladonia. The ass. Cadonio arbusculae—Pinetum (Caj. 1921) K.-Lund 1967 contains lichen pine forests with lower number of lichens and is distributed mostly in middle part of the taiga zone. The spruce-pine forests with mixed moss-lichen cover correspond to ass. Vaccinio-Pinetum. Ass. Hedysaro-Laricetum represents rich and well differentiated larch forests in the east of European Russia.

Novel Cognitive Functions Arise at the Convergence of Macroscale Gradients

2021 ◽  
pp. 1-16
Author(s):  
Heejung Jung ◽  
Tor D. Wager ◽  
R. McKell Carter
Keyword(s):  
Brain Regions ◽  
Higher Order ◽  
Hierarchical Organization ◽  
Functional Modules ◽  
Cortical Areas ◽  
Future Space ◽  
Close Proximity ◽  
Sensory Cortices ◽  
Developmental Characteristics ◽  
The Brain

Abstract Functions in higher-order brain regions are the source of extensive debate. Although past trends have been to describe the brain—especially posterior cortical areas—in terms of a set of functional modules, a new emerging paradigm focuses on the integration of proximal functions. In this review, we synthesize emerging evidence that a variety of novel functions in the higher-order brain regions are due to convergence: convergence of macroscale gradients brings feature-rich representations into close proximity, presenting an opportunity for novel functions to arise. Using the TPJ as an example, we demonstrate that convergence is enabled via three properties of the brain: (1) hierarchical organization, (2) abstraction, and (3) equidistance. As gradients travel from primary sensory cortices to higher-order brain regions, information becomes abstracted and hierarchical, and eventually, gradients meet at a point maximally and equally distant from their sensory origins. This convergence, which produces multifaceted combinations, such as mentalizing another person's thought or projecting into a future space, parallels evolutionary and developmental characteristics in such regions, resulting in new cognitive and affective faculties.

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