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Context: Climate and land-use changes affect species ranges and movements. However, these changes are usually overlooked in connectivity studies, and this could have adverse consequences in the definition of effective management measures. Objectives: We evaluated two ways to incorporate landscape dynamics: (i) by analyzing connectivity as a fluctuating phenomenon (i.e., time-varying connectivity); and (ii) by analyzing species movements from past to current ranges (i.e., spatio-temporal connectivity). We also compared these dynamic approaches with traditional static connectivity methods. Methods: We compared the overall connectivity values and the prioritization of critical habitat patches according to dynamic and static approaches using habitat availability metrics (Probability of Connectivity and Equivalent Connected Area). This comparative research was conducted for species associated with broadleaf forests of the different ecoregions of the Iberian Peninsula. We considered species habitat preferences during movement and a wide range of dispersal abilities to assess functional connectivity. Results: Static approaches generated varying overall connectivity values and priority patches depending on the time snapshot considered and different from those generated by dynamic approaches. The two dynamic connectivity approaches resulted in very similar priority conservation patches, indicating their potential to guide enduring conservation measures that enhance connectivity between contemporary habitat patches at multiple time snapshots but also species range shifts in time. Conclusions: Connectivity is affected by landscape changes, and only dynamic approaches can overcome the issues associated with these changes and provide valuable information to guide improved and enduring measures in changing landscapes. [ABSTRACT FROM AUTHOR]

Context: Landscape connectivity plays a key role in determining the persistence of species inhabiting fragmented habitat patches. In dynamic landscapes, most studies measure connectivity at multiple time steps, but pay less attention to explicitly quantifying its temporal dynamics to gain insights into its role in biodiversity patterns, thereby enabling more effective operational outcomes. Objectives: This article aimed at making an overview of the existing methods for the assessment of the temporal dynamics of connectivity. By analysing their differences and possible applications, we aimed to highlight knowledge gap and future research directions. Methods: We conducted a systematic review of literature dealing with the assessment of the temporal dynamics of connectivity and obtained 32 studies. Results: We presented two main approaches based on graph theory and compared them from conceptual and operational perspectives. The first widely used approach, accounting only for the spatial dispersal of organisms, quantifies temporal changes in spatial connectivity. Based on two or multiple time steps in the time series, this approach enables assessment of the sense and magnitude of the temporal changes in spatial connectivity. The second recently developed approach quantifies spatio-temporal connectivity, thus accounting for both spatial and temporal dispersal. So far, this holistic assessment of spatio-temporal connectivity only covers two time steps. Conclusion: Existing methods for the assessment of the temporal dynamics of connectivity provide indicators to advance our understanding of biodiversity patterns, and to be able to implement measures to conserve and restore connectivity. We propose future directions to develop these methods. [ABSTRACT FROM AUTHOR]

Habitat fragmentation has largely reduced biodiversity in the urban fringe. The prioritization of individual habitat patches can provide spatially explicit guidance for ecological conservation and restoration. Numerous studies discussed the effectiveness of purely spatial connectivity metrics to rank the conservation priority of habitats, but hardly resolved this issue in a dynamic landscape context. Meanwhile, spatio-temporal connectivity metrics were usually applied at the landscape scale, but are rarely extended to determine habitat priority at the patch scale. As such, we extend a generalized betweenness centrality metric into spatio-temporal connectivity networks to evaluate conservation priorities of individual habitat patches from a dynamic landscape perspective. The contribution rates of spatio-temporal connectivity metrics are examined at varying dispersal distances of the target species. Caidian District, the fringe of Wuhan City in central China, is taken as a case study. The results illustrate that a net decrease in habitat amounts and quality from 2005 to 2015 was mainly caused by urban expansion and agricultural production. The positive contribution rates of spatio-temporal connectivity metrics are observed at distance thresholds exceeding 200 m at the landscape scale, which allows us to capture the response of habitat priority to landscape dynamics. Accordingly, we develop a balanced conservation strategy for multiple species and the targeted conservation measures based on the coupled analysis of quality and conservation priority of habitat patches. Our findings are expected to provide solid support for biodiversity conservation in urban growth.

Landscape connectivity is important for all organisms as it directly affects population dynamics. Yet, rapid urbanization has caused serious landscape fragmentation, which is the primary contributor of species extinctions worldwide. Previous studies have mostly used spatial snap-shots to evaluate the impact of urban expansion on landscape connectivity. However, the interactions among habitats over time in dynamic landscapes have been largely ignored. Here, we demonstrated that overlooking temporal connectivity can lead to the overestimation of the impact of urban expansion. How much greater the overestimation is depends on the amount of net habitat loss. Moreover, we showed that landscape connectivity may have a delayed response to urban expansion. Our analysis shifts the way to understand the ecological consequences of urban expansion. Our framework can guide sustainable urban development and can be inspiring to conservation practices under other contexts (e.g., climate change).

Abstract Spatio-temporal connectivity patterns of a wetland as a function of the land use/land cover (LULC) of its catchment have been analysed in a GIS environment. An innovative method has been implemented for mapping 'dynamic hydrological connectivity' for a water-stressed wetland of Kosi-Ganga interfluve area in the middle Ganga Plains, India for pre- and post-monsoon seasons over a time-span of 29 years (1989 to 2017). It was accomplished by using the time-series NDVI (Normalized Difference Vegetation Index) data and the connectivity response unit (CRU) approach by applying geostatistical methods namely the Getis-Ord Gi* and Mann-Kendall trend test statistics. The study area is principally a rain-fed wetland located in flat terrain (average slope of ~2°) under intensive agriculture and receives water as overland flows. The agriculture dominated LULC in this region is controlling the wetland-catchment connectivity scenarios and the overall connectivity potential of the catchment is higher in the pre-monsoon compared to the post-monsoon season. High and low connectivity potentials of different areas of the catchment with respect to the wetland have been classified into three types: persistent, intensifying, and diminishing. The areas with 'persistent' high or low connectivity potentials have been attributed to the topographic factors which are static in nature, such as the proximity to the wetland and the presence of other geomorphic features. The 'intensifying' and 'diminishing' clusters have been linked to changing LULC patterns. The proposed method holds significant implications for the restoration of wetland-catchment connectivity and can be applied in any flatland terrain where hydrological connectivity is strongly influenced by the surface impedance induced by LULC. Graphical abstract Unlabelled Image Highlights • Dynamic connectivity patterns of a wetland as a function of the land use/land cover • Concept of Connectivity Response Units' (CRUs) coupled with space-time cubes • Wetland-catchment connectivity higher for pre-monsoon compared to post-monsoon • 'Persistent' clusters act like 'buffers' and 'barriers'. • 'Intensifying' and 'diminishing' clusters result from changing LULC patterns. [ABSTRACT FROM AUTHOR]