scholarly journals General Landscape Connectivity Model (GLCM): a new way to map whole of landscape biodiversity functional connectivity for operational planning and reporting

2022 ◽  
Vol 465 ◽  
pp. 109858
Author(s):  
Michael J. Drielsma ◽  
Jamie Love ◽  
Subhashni Taylor ◽  
Rajesh Thapa ◽  
Kristen J. Williams
2021 ◽  
Author(s):  
James D. Karimi ◽  
Jim A. Harris ◽  
Ron Corstanje

Abstract Context Landscape connectivity is assumed to influence ecosystem service (ES) trade-offs and synergies. However, empirical studies of the effect of landscape connectivity on ES trade-offs and synergies are limited, especially in urban areas where the interactions between patterns and processes are complex. Objectives The objectives of this study were to use a Bayesian Belief Network approach to (1) assess whether functional connectivity drives ES trade-offs and synergies in urban areas and (2) assess the influence of connectivity on the supply of ESs. Methods We used circuit theory to model urban bird flow of P. major and C. caeruleus at a 2 m spatial resolution in Bedford, Luton and Milton Keynes, UK, and Bayesian Belief Networks (BBNs) to assess the sensitivity of ES trade-offs and synergies model outputs to landscape and patch structural characteristics (patch area, connectivity and bird species abundance). Results We found that functional connectivity was the most influential variable in determining two of three ES trade-offs and synergies. Patch area and connectivity exerted a strong influence on ES trade-offs and synergies. Low patch area and low to moderately low connectivity were associated with high levels of ES trade-offs and synergies. Conclusions This study demonstrates that landscape connectivity is an influential determinant of ES trade-offs and synergies and supports the conviction that larger and better-connected habitat patches increase ES provision. A BBN approach is proposed as a feasible method of ES trade-off and synergy prediction in complex landscapes. Our findings can prove to be informative for urban ES management.


Land ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. 459
Author(s):  
Thais Martins Issii ◽  
Erico Fernando Lopes Pereira-Silva ◽  
Carlos Tomás López de Pablo ◽  
Rozely Ferreira dos Santos ◽  
Elisa Hardt

Landscape connectivity can be assessed based on the physical connection (structural connectivity) or the maintenance of flow among habitats depending on the species (functional connectivity). The lack of empirical data on the dispersal capacity of species can lead to the use of simple structural measures. Comparisons between these approaches can improve decision-making processes for the conservation or restoration of habitats in fragmented landscapes, such as the Cerrado biome. This study aimed to understand the correspondence between the measures of landscape structural and functional connectivity for Cerrado plants. Three landscapes with cerradão patches in a pasture matrix were selected for the application of these metrics based on the functional connectivity of four profiles of plant dispersal capacity. The results showed divergent interpretations between the measures of landscape structural and functional connectivity, indicating that the assessment of biodiversity conservation and landscape connectivity is dependent on the set of metrics chosen. Structurally, the studied landscapes had the same number of cerradão patches but varied in optimal resource availability, isolation, heterogeneity, and aggregation. Functional connectivity was low for all profiles (based on the integral index of connectivity—IIC) and null for species with a low dispersal capacity (based on the connectance index—CONNECT), indicating that species with a medium- to long-distance dispersal capacity may be less affected by the history of losses and fragmentation of the Cerrado in the pasture matrix. The functional connectivity metrics used allowed a more robust analysis and, apparently, better reflected reality, but the lack of empirical data on dispersal capacity and the difficulty in choosing an indicator organism can limit their use in the management and planning of conservation and restoration areas.


2021 ◽  
Author(s):  
James Karimi ◽  
Jim A. Harris ◽  
Ron Concorstanje

Abstract Context Landscape connectivity is assumed to influence ecosystem service (ES) trade-offs and synergies. However, empirical studies of the effect of landscape connectivity on ES trade-offs and synergies are limited, especially in urban areas where the interactions between patterns and processes are complex.Objectives The objectives of this study were to use a Bayesian Belief Network approach to (1) assess whether functional connectivity drives ES trade-offs and synergies in urban areas and (2) assess the influence of connectivity on the supply of ESs.Methods We used circuit theory to model urban bird flow of P. major and C. caeruleus at a 2 m spatial resolution in Bedford, Luton and Milton Keynes, UK, and Bayesian Belief Networks (BBNs) to assess the sensitivity of ES trade-offs and synergies model outputs to landscape and patch structural characteristics (patch area, connectivity and bird species abundance).Results We found that functional connectivity was the most influential variable in determining two of three ES trade-offs and synergies. Patch area and connectivity exerted a strong influence on ES trade-offs and synergies. Low patch area and low to moderately low connectivity were associated with high levels of ES trade-offs and synergies.Conclusions This study demonstrates that landscape connectivity is an influential determinant of ES trade-offs and synergies and supports the conviction that larger and better-connected habitat patches increase ES provision. A BBN approach is proposed as a feasible method of ES trade-off and synergy prediction in complex landscapes. Our findings can prove to be informative for urban ES management.


2017 ◽  
Author(s):  
Mara Ines Espinosa Herazo ◽  
Nicolas Gouin ◽  
Francisco Antonio Squeo Porcile ◽  
David López Aspe ◽  
Angéline Bertin

Connectivity between populations plays a key role in the long-term persistence of species in fragmented habitats. It is an issue of concern for the preservation of biodiversity in drylands since landscapes in water limited environments are characterized by low habitat cover, high habitat fragmentation and harsh matrices, and are being rapidly degraded at the global scale. In this study, we modelled landscape connectivity between the 11 remnant coastal and Andean populations of the guanaco Lama guanicoe, an emblematic herbivore indigenous to South America, in Chile's arid Norte Chico. We first produced a habitat surface model to derive a regional surface resistance map; and we then used circuit theory to map functional connectivity, investigate the degree of isolation of the populations, and identify those that most contribute to the network patch connectivity. Predicted suitable habitat for L. guanicoe represented about 25% of the study region (i.e. 29,173 km2), and was heterogeneously distributed along a continuous stretch along the Andes, and discontinuous patches along the coast. As a result, we found that high connectivity current flows in the mid and high Andes formed a wide continuous connectivity corridor enabling connectivity between all the high Andean populations. Coastal populations, in contrast, were predicted to be more isolated. They only connect to medium and high altitude populations, and for two of them, animal movement was linked to the effectiveness of wildlife crossings. Based on the degree of connectivity, population size, and local threats, the coastal and the northernmost populations were identified as being most vulnerable, while the Andean populations appeared to be least at risk, even when located near areas of mining activity. Collectively, our results suggest that functional connectivity is an issue of concern for L. guanicoe in Chile’s Norte Chico, and that future conservation and management plans should adopt a landscape strategy aiming at conserving the functional connectivity between the coastal and Andean populations, and at protecting the habitat patches likely to act as stepping stones within the connectivity network.


2021 ◽  
Author(s):  
Andrés Peredo Arce ◽  
Martin Palt ◽  
Martin Schletterer ◽  
Jochem Kail

<p>In the degraded European landscapes riparian corridors had have become key features to maintain connectivity between habitat patches for multitude of organisms. This role of riparian forests has been assessed from the purely structural point of view, to complex models specific for particular species or groups of species, from mammals to plants, from endangered to invasive species.</p><p>Dispersion is a key part of the lifecycle of EPTs (Ephemeroptera, Plecoptera and Trichoptera) as they live most of their lives as aquatic juveniles, being drifted downstream, and disperse back upstream when they become short-lived winged adults. These three families of aquatic macroinvertebrates are widely used as bioindicators because of their sensitivity to water pollution and habitat degradation, but little is known about how the riparian vegetation impacts their ability to disperse and recolonize. For example, riparian vegetation could help EPTs dispersion by protecting them from harsh weather conditions, or by helping them to orientate themselves by changing how the reflexion of the light on the water polarises.</p><p>Nevertheless, connectivity is not the only driver of the EPT community as other parameters can have a direct effect on the community composition. For example, water pollution is an important driver of the freshwater macroinvertebrate community and in locations where pollution is high is not expected to find almost any EPTs individual regardless of the landscape connectivity. Furthermore, other landscape features can hinder the role of riparian forests as corridors for being a barrier to EPT dispersion, like dams or coniferous forests.</p><p>In this study we compare the EPT communities on 120 pairs of sites, each pair located in the same river at 1 to 5 km distance, with different riparian vegetation conditions in Western Germany. The communities are characterised by their overall dispersion capacity using the Species Flying Propensity index (Sarremejane et al. 2017). The riparian vegetation is identified using areal images in the 10 meters and 30 meters buffer from the river.</p><p>We expect that riparian forest fragmentation will directly impact functional connectivity, and therefore, in locations with less fragmented riparian forests the EPT community will be mainly composed by weak dispersers (and <em>vice versa</em>). Nevertheless, covariates that can impact or mask this effect were taken into account: catchment land use, saprobic pollution, naturalness, hidromorphological hydromorphological degradation and also other features as coniferous forests or dams.</p>


Neurosurgery ◽  
2019 ◽  
Vol 86 (6) ◽  
pp. 792-801 ◽  
Author(s):  
Sarah E Goodale ◽  
Hernán F J González ◽  
Graham W Johnson ◽  
Kanupriya Gupta ◽  
William J Rodriguez ◽  
...  

Abstract BACKGROUND Stereotactic electroencephalography (SEEG) is a minimally invasive neurosurgical method to localize epileptogenic brain regions in epilepsy but requires days in the hospital with interventions to trigger several seizures. OBJECTIVE To make initial progress in the development of network analysis methods to identify epileptogenic brain regions using brief, resting-state SEEG data segments, without requiring seizure recordings. METHODS In a cohort of 15 adult focal epilepsy patients undergoing SEEG, we evaluated functional connectivity (alpha-band imaginary coherence) across sampled regions using brief (2 min) resting-state data segments. Bootstrapped logistic regression was used to generate a model to predict epileptogenicity of individual regions. RESULTS Compared to nonepileptogenic structures, we found increased functional connectivity within epileptogenic regions (P < .05) and between epileptogenic areas and other structures (P < .01, paired t-tests, corrected). Epileptogenic areas also demonstrated higher clustering coefficient (P < .01) and betweenness centrality (P < .01), and greater decay of functional connectivity with distance (P < .05, paired t-tests, corrected). Our functional connectivity model to predict epileptogenicity of individual regions demonstrated an area under the curve of 0.78 and accuracy of 80.4%. CONCLUSION Our study represents a preliminary step towards defining resting-state SEEG functional connectivity patterns to help localize epileptogenic brain regions ahead of neurosurgical treatment without requiring seizure recordings.


2021 ◽  
Author(s):  
Sonsoles Alonso Martinez ◽  
Alberto Llera Arenas ◽  
Gert T Ter Horst ◽  
Diego Vidaurre

In order to continuously respond to a changing environment and support self-generating cognition and behaviour, neural communication must be highly flexible and dynamic at the same time than hierarchically organized. While whole-brain fMRI measures have revealed robust yet changing patterns of statistical dependencies between regions, it is not clear whether these statistical patterns (referred to as functional connectivity) can reflect dynamic large-scale communication in a way that is relevant to cognition. For functional connectivity to reflect actual communication, we propose three necessary conditions: it must span sufficient temporal complexity to support the needs of cognition while still being highly organized so that the system behaves reliably; it must be able to adapt to the current behavioural context; and it must exhibit fluctuations at sufficiently short timescales. In this paper, we introduce principal components of connectivity analysis (PCCA), an approach based on running principal component analysis on multiple runs of a time-varying functional connectivity model to show that functional connectivity follows low- yet multi-dimensional trajectories that can be reliably measured, and that these trajectories meet the aforementioned criteria to index flexible communication between neural populations and support moment-to-moment cognition.


2020 ◽  
Author(s):  
Adam Kimberley ◽  
Danny Hooftman ◽  
James M. Bullock ◽  
Olivier Honnay ◽  
Patricia Krickl ◽  
...  

Abstract Context Functional connectivity is vital for plant species dispersal, but little is known about how habitat loss and the presence of green infrastructure interact to affect both functional and structural connectivity, and the impacts of each on species groups. Objectives We investigate how changes in the spatial configuration of species-rich grasslands and related green infrastructure such as road verges, hedgerows and forest borders in three European countries have influenced landscape connectivity, and the effects on grassland plant biodiversity. Methods We mapped past and present land use for 36 landscapes in Belgium, Germany and Sweden, to estimate connectivity based on simple habitat spatial configuration (structural connectivity) and accounting for effective dispersal and establishment (functional connectivity) around focal grasslands. We used the resulting measures of landscape change to interpret patterns in plant communities. Results Increased presence of landscape connecting elements could not compensate for large scale losses of grassland area resulting in substantial declines in structural and functional connectivity. Generalist species were negatively affected by connectivity, and responded most strongly to structural connectivity, while functional connectivity determined the occurrence of grassland specialists in focal grasslands. Restored patches had more generalist species, and a lower density of grassland specialist species than ancient patches. Conclusions Protecting both species rich grasslands and dispersal pathways within landscapes is essential for maintaining grassland biodiversity. Our results show that increases in green infrastructure have not been sufficient to offset loss of semi-natural habitat, and that landscape links must be functionally effective in order to contribute to grassland diversity.


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