Diving Beetle (Coleoptera: Dytiscidae) Community Dissimilarity Reveals How Low Landscape Connectivity Restricts the Ecological Value of Urban Ponds

Abstract Context: Structural and functional connectivity, as subconcepts of landscape connectivity, are key factors in biodiversity conservation and management. Previous studies have focused on the consequences of connectivity for populations of terrestrial organisms, which may not be appropriate for aquatic organisms. Objectives: As landscape connectivity critically affects the potential value of ponds for biodiversity, here we used diving beetles (Dytiscidae), an indicator taxon of wetland biodiversity, to investigate how structural connectivity affects functional connectivity to aquatic invertebrates in an urban landscape. Methods: We assessed pairwise similarities of dytiscid community, i.e. the variation of species composition between clustered and isolated ponds in the Helsinki Metropolitan Area, Finland. We investigated how dytiscid community similarity is affected by Euclidean distances between ponds, as an indicator of structural connectivity. Results: We found that clustered ponds shared more species than isolated ponds. Dytiscid species community similarity responded negatively to increasing Euclidean distance between ponds. Effectively dispersing species were widely distributed across the landscape, while poor dispersers were scarcely distributed in the same landscape. Conclusions: Structural connectivity determines which species are able to disperse successfully, with poor dispersers restricted to well-connected ponds. The different responses of effective dispersers and poor dispersers to the same structural connectivity indicates that functional connectivity determines species composition. We recommend providing well-connected aquatic habitats in urban landscapes and the implementation of measures to reduce isolation of wetland assemblages. Even clustered ponds need dispersal from other habitats to ensure their contribution to urban biodiversity.

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Is There an Equivalence between Measures of Landscape Structural and Functional Connectivity for Plants in Conservation Assessments of the Cerrado?

Land ◽

10.3390/land9110459 ◽

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

Keyword(s):

Functional Connectivity ◽

Empirical Data ◽

Landscape Connectivity ◽

Structural Connectivity ◽

Long Distance ◽

Dispersal Capacity ◽

Plant Dispersal ◽

Optimal Resource ◽

History Of ◽

Conservation Assessments

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.

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How urban forest can support Protected Areas connectivity?

10.21203/rs.3.rs-1017653/v1 ◽

2021 ◽

Author(s):

Marina Pannunzio Ribeiro ◽

Kaline de Mello ◽

Roberta Averna Valente

Keyword(s):

Graph Theory ◽

Functional Connectivity ◽

Protected Areas ◽

Urban Landscape ◽

Urban Forest ◽

Urban Landscapes ◽

Natural Ecosystem ◽

Forest Fragments ◽

Private Lands ◽

Focal Species

Abstract The highly modified urban matrix becomes an inhospitable environment for many species because the natural vegetation fragments are highly fragmented and often isolated in the landscape. Protected Areas (PAs) located closer or within urban areas may not achieve their goal of protecting local or regional biodiversity. Thus, the proposition of ecological corridors aims to connect the PAs, providing the dispersion of species in anthropogenic landscapes. In this context, this study aimed to evaluate the PAs connectivity in an urban landscape and understand if urban forest fragments can support their connectivity, generating important information for biodiversity conservation and urban planning. For this, we used models based on Graph Theory to assess the functional connectivity among PAs. The focal species used were Atlantic Forest birds. We used the participatory technique to assess their dispersal capabilities, and this information was used to create a resistance surface map. The focal species movement in the landscape was modeled through Graph Theory. This model evaluated the functional connectivity and extracted the least-cost paths between PAs and other forest fragments that designed the urban ecological network. We identified that few PAs are connected in the urban landscape of Sorocaba city and its surroundings and 28 forest fragments that are important to support the connectivity among PAs. Among these, only four fragments are located within a PA. The other 24 forest fragments located outside PAs should be the center of attention for forest conservation and restoration actions, as they can improve the connectivity between the PAs. Our results show that PAs connectivity in urban landscapes depends on incentives for native vegetation conservation on private lands once most of the important forest fragments for the PAs connectivity are located in these areas. In addition, the restoration of riparian zones is important because they compose a great ecological corridor in the urban landscape. Strategies that increase the permeability of the matrix (e.g., increasing green spaces and gardens) and restoring target fragments are also important. Finally, land-use planning, focusing on natural ecosystem conservation and combating urban sprawl, is necessary to promote PAs connectivity in urban landscapes.

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Research on the Urban Landscape System Planning and Layout Based on the Perspective of Ecological Infrastructure

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.450-451.1274 ◽

2012 ◽

Vol 450-451 ◽

pp. 1274-1279 ◽

Cited By ~ 1

Author(s):

Yi Deng ◽

Ling Cai ◽

Zhao Xian Gong

Keyword(s):

Nearest Neighbor ◽

Urban Landscape ◽

Landscape Connectivity ◽

Urban System ◽

Urban Landscapes ◽

Landscape Index ◽

Ecological Infrastructure ◽

Distribution Mode ◽

Landscape System ◽

Project Location

As the ecological infrastructure, the development of the ecological function of urban landscapes is determined not only by the reasonable design on its own scale, but also by the interaction of the urban-scaled landscape system. Virtually, the planning and layout of the urban landscape system represent the reasonable position of various projects in the overall landscape structure. The current paper, combined with the landscape ecology theory, put forward the idea primarily determining the distribution of single landscape projects through the priority of single project location, as well as the selection of ecological strategic points. In considering the distribution mode and landscape index, the overall layout of urban landscape system can be adjusted and optimized by consulting the landscape connectivity index, PX, and the nearest neighbor index, NNI. This planning idea is in favor of sustaining and strengthening the continuity of the whole landscape pattern, and maintaining the general ecological security of urban system.

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Functional rather than structural connectivity explains grassland plant diversity patterns following landscape scale habitat loss

Landscape Ecology ◽

10.1007/s10980-020-01138-x ◽

2020 ◽

Author(s):

Adam Kimberley ◽

Danny Hooftman ◽

James M. Bullock ◽

Olivier Honnay ◽

Patricia Krickl ◽

...

Keyword(s):

Functional Connectivity ◽

Habitat Loss ◽

Green Infrastructure ◽

Large Scale ◽

Spatial Configuration ◽

Landscape Connectivity ◽

Natural Habitat ◽

Structural Connectivity ◽

Species Dispersal ◽

Generalist Species

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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Using Bayesian Belief Networks to assess the influence of landscape connectivity on ecosystem service trade-offs and synergies in urban landscapes in the UK

Landscape Ecology ◽

10.1007/s10980-021-01307-6 ◽

2021 ◽

Author(s):

James D. Karimi ◽

Jim A. Harris ◽

Ron Corstanje

Keyword(s):

Functional Connectivity ◽

Ecosystem Service ◽

Urban Areas ◽

Landscape Connectivity ◽

Structural Characteristics ◽

Bird Species ◽

Bayesian Belief Networks ◽

Belief Networks ◽

Patch Area ◽

Trade Offs

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.

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Functional connectivity of fMRI using differential covariance predicts structural connectivity and behavioral reaction times

10.1101/2021.09.01.458609 ◽

2021 ◽

Author(s):

Yusi Chen ◽

Qasim Bukhari ◽

Tiger Wutu Lin ◽

Terrence J Sejnowski

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Functional Connectivity ◽

Resting State ◽

Structural Connectivity ◽

Reaction Times ◽

Resonance Imaging ◽

Brain Areas ◽

Human Connectome Project ◽

Wide Range

Recordings from resting state functional magnetic resonance imaging (rs-fMRI) reflect the influence of pathways between brain areas. A wide range of methods have been proposed to measure this functional connectivity (FC), but the lack of ''ground truth'' has made it difficult to systematically validate them. Most measures of FC produce connectivity estimates that are symmetrical between brain areas. Differential covariance (dCov) is an algorithm for analyzing FC with directed graph edges. Applied to synthetic datasets, dCov-FC was more effective than covariance and partial correlation in reducing false positive connections and more accurately matching the underlying structural connectivity. When we applied dCov-FC to resting state fMRI recordings from the human connectome project (HCP) and anesthetized mice, dCov-FC accurately identified strong cortical connections from diffusion Magnetic Resonance Imaging (dMRI) in individual humans and viral tract tracing in mice. In addition, those HCP subjects whose rs-fMRI were more integrated, as assessed by a graph-theoretic measure, tended to have shorter reaction times in several behavioral tests. Thus, dCov-FC was able to identify anatomically verified connectivity that yielded measures of brain integration causally related to behavior.

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Distinct structure-function relationships across cortical regions and connectivity scales in the rat brain

10.1101/742833 ◽

2019 ◽

Author(s):

Milou Straathof ◽

Michel R.T. Sinke ◽

Theresia J.M. Roelofs ◽

Erwin L.A. Blezer ◽

R. Angela Sarabdjitsingh ◽

...

Keyword(s):

Functional Connectivity ◽

Structure Function ◽

Rat Brain ◽

Resting State ◽

Structural Connectivity ◽

Distinct Structure ◽

Macro Scale ◽

Function Relationship ◽

The Brain ◽

Meso Scale

AbstractAn improved understanding of the structure-function relationship in the brain is necessary to know to what degree structural connectivity underpins abnormal functional connectivity seen in many disorders. We integrated high-field resting-state fMRI-based functional connectivity with high-resolution macro-scale diffusion-based and meso-scale neuronal tracer-based structural connectivity, to obtain an accurate depiction of the structure-function relationship in the rat brain. Our main goal was to identify to what extent structural and functional connectivity strengths are correlated, macro- and meso-scopically, across the cortex. Correlation analyses revealed a positive correspondence between functional connectivity and macro-scale diffusion-based structural connectivity, but no correspondence between functional connectivity and meso-scale neuronal tracer-based structural connectivity. Locally, strong functional connectivity was found in two well-known resting-state networks: the sensorimotor and default mode network. Strong functional connectivity within these networks coincided with strong short-range intrahemispheric structural connectivity, but with weak heterotopic interhemispheric and long-range intrahemispheric structural connectivity. Our study indicates the importance of combining measures of connectivity at distinct hierarchical levels to accurately determine connectivity across networks in the healthy and diseased brain. Distinct structure-function relationships across the brain can explain the organization of networks and may underlie variations in the impact of structural damage on functional networks and behavior.

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Structure supports function: informing directed and dynamic functional connectivity with anatomical priors

10.1101/2021.05.11.443529 ◽

2021 ◽

Author(s):

David Pascucci ◽

Maria Rubega ◽

Joan Rue-Queralt ◽

Sebastien Tourbier ◽

Patric Hagmann ◽

...

Keyword(s):

Functional Connectivity ◽

Diffusion Tensor ◽

Meta Analysis ◽

Structural Connectivity ◽

Brain Regions ◽

Noise Perturbation ◽

Eeg Data ◽

Functional Brain Networks ◽

Anatomical Priors ◽

And Diffusion

The dynamic repertoire of functional brain networks is constrained by the underlying topology of structural connections: the lack of a direct structural link between two brain regions prevents direct functional interactions. Despite the intrinsic relationship between structural (SC) and functional connectivity (FC), integrative and multimodal approaches to combine the two remain limited, especially for electrophysiological data. In the present work, we propose a new linear adaptive filter for estimating dynamic and directed FC using structural connectivity information as priors. We tested the filter in rat epicranial recordings and human event-related EEG data, using SC priors from a meta-analysis of tracer studies and diffusion tensor imaging metrics, respectively. Our results show that SC priors increase the resilience of FC estimates to noise perturbation while promoting sparser networks under biologically plausible constraints. The proposed filter provides intrinsic protection against SC-related false negatives, as well as robustness against false positives, representing a valuable new method for multimodal imaging and dynamic FC analysis.

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Joint estimation of neural sources and their functional connections from MEG data

10.1101/2020.10.04.325563 ◽

2020 ◽

Author(s):

Narayan Puthanmadam Subramaniyam ◽

Filip Tronarp ◽

Simo Särkkä ◽

Lauri Parkkonen

Keyword(s):

Time Series ◽

Functional Connectivity ◽

Structural Connectivity ◽

Identification Problem ◽

Joint Estimation ◽

Bayesian Filtering ◽

Sequential Approach ◽

Connectivity Structure ◽

Saem Algorithm ◽

Functional Connections

AbstractCurrent techniques to estimate directed functional connectivity from magnetoencephalography (MEG) signals involve two sequential steps; 1) Estimation of the sources and their amplitude time series from the MEG data by solving the inverse problem, and 2) fitting a multivariate autoregressive (MVAR) model to these time series for the estimation of AR coefficients, which reflect the directed interactions between the sources. However, such a sequential approach is not optimal since i) source estimation algorithms typically assume that the sources are independent, ii) the information provided by the connectivity structure is not used to inform the estimation of source amplitudes, and iii) the limited spatial resolution of source estimates often leads to spurious connectivity due to spatial leakage.Here, we present an algorithm to jointly estimate the source and connectivity parameters using Bayesian filtering, which does not require anatomical constraints in form of structural connectivity or a-priori specified regions-of-interest. By formulating a state-space model for the locations and amplitudes of a given number of sources, we show that estimation of functional connectivity can be reduced to a system identification problem. We derive a solution to this problem using a variant of the expectation–maximization (EM) algorithm known as stochastic approximation EM (SAEM).Compared to the traditional two-step approach, the joint approach using the SAEM algorithm provides a more accurate reconstruction of connectivity parameters, which we show with a connectivity benchmark simulation as well as with an electrocorticography-based simulation of MEG data. Using real MEG responses to visually presented faces in 16 subjects, we also demonstrate that our method gives source and connectivity estimates that are both physiologically plausible and largely consistent across subjects. In conclusion, the proposed joint-estimation approach based on the SAEM algorithm outperforms the traditional two-step approach in determining functional connectivity structure in MEG data.

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URBAN LANDSCAPE ASSESSMENT

Proceedings 24th ISUF 2017 - City and Territory in the Globalization Age ◽

10.4995/isuf2017.2017.6020 ◽

2017 ◽

Author(s):

Vicente Collado Capilla ◽

Sonia Gómez-Pardo Gabaldón

Keyword(s):

New York ◽

Urban Landscape ◽

Tall Buildings ◽

Daily Basis ◽

Landscape Assessment ◽

Urban Landscapes ◽

Cultural Issues ◽

Strategic Element ◽

The City

URBAN LANDSCAPE ASSESSMENT Vicente Collado Capilla1 and Sonia Gómez-Pardo Gabaldón21Servicio de Infraestructura Verde y Paisaje. Generalitat Valenciana. Ciutat Administrativa 9 D'Octubre-Torre 1, C/ Castán Tobeñas 77, 46018 Valencia; 2Servicio Territorial de Urbanismo. Provincia de Valencia. Generalitat Valenciana. Prop I, C/ Gregorio Gea, nº 27, 46009 Valencia. E-mail: [email protected] [email protected] Key words: urban_landscape, streetcape, landscape_value, andscape_assessment, landscape_preferences. The urban landscape assesment as an important element in the quality of life and the sustainable development of the city constitutes an incipient field of investigation from a new perspective that adds meanings and values. An analysis of the different methodological developments and national and international experiences in the assessment of these landscapes will highlight its importance as a strategic element to improve the quality of the city. It starts from the concept of assessment as a system where tangible and intangible values are considered by the population and the experts. These include among other formal, economic, environmental, social, cultural issues (…) and the relationships between them. Consideration of the opinions of experts from different points of view such as urbanism and architecture but also environment, economy, geography, history, archeology, sociology, social assistance, etc. Together with the preferences expressed by the population regarding the spaces they inhabit on a daily basis and their aspirations, strengthen the sense of belonging and the identity of the place as key elements in the perception of the urban landscapes that allows to contribute new qualities, integration criteria and contemporary values to any type of intervention. These are strategies and intervention procedures that start from the complexity of the city as a system and incorporate the perception that citizens have or will have of their immediate environment. References: Czynska Klara and Pawel Rubinowicz (2015). ´Visual protection Surface method: Cityscape values in context of tall buildings´. SSS10 Proceedings of the 10 th International Space Syntax Symposium. Paquette Sylvain (2008). Guide de gestion des paysages au Québec. Université de Montréal Pallasmaa, Juhani (2005). The Eyes of the Skin. Architecture and the Senses. New York: John Wiley. Ministry of Environment and Energy The National Forest and Nature Agency (1997). International Survey of Architectural Values in the Environment. Denmark . The Landscape Institute and Institute of Environmental Management & Assessment (2013). Guidelines for Landscape and Visual Impact Assessment. Third Edition, London: Routledge.

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