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One of the main goals of community ecology is to measure the relative importance of environmental filters to understand patterns of species distribution at different temporal and spatial scales. Likewise, the identification of factors that shape symbiont metacommunity structures is important in disease ecology because resulting structures drive disease transmission. We tested the hypothesis that distributions of virus species and viral families from rodents and bats are defined by shared responses to host phylogeny and host functional characteristics, shaping the viral metacommunity structures at four spatial scales (Continental, Biogeographical, Zoogeographical, and Regional). The contribution of host phylogeny and host traits to the metacommunity of viruses at each spatial scale was calculated using a redundant analysis of canonical ordering (RDA). For rodents, at American Continental scale the coherence of viral species metacommunity increased while the spatial scale decreased and Quasi-Clementsian structures were observed. This pattern suggests a restricted distribution of viruses through their hosts, while in the Big Mass (Europe, Africa, and Asia), the coherence decreased as spatial scale decreased. Viral species metacommunities associated with bats was dominated by random structures along all spatial scales. We suggest that this random pattern is a result of the presence of viruses with high occupancy range such as rabies (73%) and coronavirus (27%), that disrupt such structures. At viral family scale, viral metacommunities associated with bats showed coherent structures, with the emergence of Quasi- Clementsian and Checkerboard structures. RDA analysis indicates that the assemblage of viral diversity associated with rodents and bats responds to phylogenetic and functional characteristics, which alternate between spatial scales. Several of these variations could be subject to the spatial scale, in spite of this, we could identify patterns at macro ecological scale. The application of metacommunity theory at symbiont scales is particularly useful for large-scale ecological analysis. Understanding the rules of host-virus association can be useful to take better decisions in epidemiological surveillance, control and even predictions of viral distribution and dissemination.

Open access

How are bryophyte alpha and beta diversities distributed across spatial scales along an elevational gradient in an oceanic island? Which mechanisms and drivers operate to shape them? Starting from a multiscale hierarchical sampling approach along an 1000 m elevational transect, we used additive diversity partitioning and null modeling to evaluate the contributions of the alpha and beta diversity components to overall bryophyte diversity in Terceira Island, Azores. Substrate-level diversity patterns were explored by means of the Sørensen Similarity Index and the Lloyd Index of Patchiness. Elevation-level beta diversity was decomposed into its replacement and richness differences components, with several environmental variables being evaluated as diversity predictors. Bryophyte diversity proved to be primarily due to beta diversity between elevation sites, followed by diversity among substrates. Compositional differences between neighboring sites decreased with elevation, being mainly caused by species replacement and correlating with differences in relative humidity and disturbance. At the substrate level, we found a great homogeneity in terms of species composition, coupled with a low substrate specialization rate. We conclude that, in Terceira’s native vegetation patches, regional processes, such as environmental gradients associated with elevation, play a greater role in shaping bryophyte diversity than local processes. Moister and less disturbed areas at mid-high elevation harbor a richer bryoflora, consistently more similar and stable between neighbouring sites. Simultaneously, the different substrates available are somewhat ecologically redundant, supporting few specialized species, pointing to these areas providing optimal habitat conditions for bryophytes. Our findings provide a better understanding of how bryophyte diversity is generated in Terceira Island, indicating that management and conservation measures should focus on island-level approaches, aiming to protect and rehabilitate additional natural vegetation patches at different elevations, especially in the severely disturbed lowlands.

Open access

H.M. Valett . 2001 . Relationships between land use, spatial scale and stream macroinvertebrate communities . Freshwater Biol. 46 : 1409 – 1424 . Srivastava , D

Open access

. Loisl , F. , G. Singer and H. Keckeis . 2014 . Method-integrated fish assemblage structure at two spatial scales along a free-flowing stretch of the Austrian Danube . Hydrobiologia 729 : 77 – 94

Open access

approach was applied by Webster et al. ( 2002 ) for estimating the spatial scales of regionalized variables. Fig. 3 Elements of a statistical control chart

Open access

former was exclusively derived from gauged records and is available from the official page of Climate for Carpathian Region Project [ 21 ]. On the other hand, CFSR weather data sets are produced on a large spatial scale, assimilating the ground

Open access

is to realize the value-added of functional elements, spatial scale and spatial significance through scientific compact and orderly organization of the form structure on the given block land, so as to enhance the efficiency of land use and urban

Open access

to highlight the high complexity of HE governance that is spread across spatial scales (regional, sub-regional, national, subnational, local and global, or external and internal) and also across a range of management and leadership bodies, functions

Open access
Imaging
Authors:
Bettina Katalin Budai
,
Veronica Frank
,
Sonaz Shariati
,
Bence Fejér
,
Ambrus Tóth
,
Vince Orbán
,
Viktor Bérczi
, and
Pál Novák Kaposi

PV phase CT images taken at baseline and two months after the initiation of treatment. Three radiomic features: the sum of target lesions, the baseline density of the dominant lesion, and the absolute change in kurtosis with a medium spatial scale

Open access
Central European Geology
Authors:
Ildikó Gyollai
,
Ákos Kereszturi
, and
Elias Chatzitheodoridis

by chemical inhomogeneity (inherited schlieren features with poorer and richer regions in Ca and Fe) within a μm spatial scale, because of the lack of time for mechanical mixing and homogenization ( Langenhorst and Poiriere 2000 ). Dingwell and Webb

Open access