The Landscape Ecology of Rivers: from Patch-Based to Spatial Network Analyses Abstract Purpose of Review We synthesize recent methodological and conceptual advances in the field of riverscape ecology, emphasizing areas of synergy with current research in landscape ecology. Recent Findings Recent advances in riverscape ecology highlight the need for spatially explicit examinations of how network structure influences ecological pattern and process, instead of the simple linear (upstream-downstream) view. Developments in GIS, remote sensing, and computer technologies already offer powerful tools for the application of patch- and gradient-based models for characterizing abiotic and biotic heterogeneity across a range of spatial and temporal scales. Along with graph-based analyses and spatial statistical stream network models (i.e., geostatistical modelling), these approaches offer improved capabilities for quantifying spatial and temporal heterogeneity and connectivity relationships, thereby allowing for rigorous and high-resolution analyses of pattern, process, and scale relationships. Summary Spatially explicit network approaches are able to quantify and predict biogeochemical, hydromorphological, and ecological patterns and processes more precisely than models based on longitudinal or lateral riverine gradients alone. Currently, local habitat characteristics appear to be more important than spatial effects in determining population and community dynamics, but this conclusion may change with direct quantification of the movement of materials, energy, and organisms along channels and across ecosystem boundaries—a key to improving riverscape ecology. Coupling spatially explicit riverscape models with optimization approaches will improve land protection and water management efforts, and help to resolve the land sharing vs. land sparing debate.

Effects of Landscape Pattern on Pollination, Pest Control, Water Quality, Flood Regulation, and Cultural Ecosystem Services: a Literature Review and Future Research Prospects Abstract Purpose of Review This review highlights recent progress on how landscape pattern (composition, configuration, landscape context, keystone landscape, scaling, and nonlinearity) affects pollination, pest control, water quality, flood control, and cultural ecosystem services (ES)—landscape esthetics and recreation. Recent Findings Landscape composition and configuration showed ES-specific effects. Recent studies confirmed that pollination increased in complex, heterogeneous landscapes with more surrounding natural/semi-natural habitats. Landscape pattern could also interact with local factors to affect pollination, with stronger effects at smaller spatial scales. For pest control, a comprehensive synthesis revealed inconsistent effects of non-crop habitat composition, perhaps due to diverse responses from different enemies and pests and complex tri-trophic interactions. Spatial configuration of land-covers, connectivity, and edge effects also mattered for pest control ES. Moreover, recent studies showed that configuration of land-covers could sometimes trump composition as the primary driver for water quality. Comparing across scales (e.g., riparian vs. watershed), landscape pattern effects on water quality tended to be more pronounced at small spatial scales. For flood control, studies showed that larger and less fragmented natural covers reduced peak runoffs, with a compositional threshold ~ 30–40%. Spatial location also mattered where imperviousness concentrated closer to outlet tended to increase peak runoffs. For cultural ES, landscape esthetics and recreation showed positive correlations with naturalness composition and landscape heterogeneity. Summary Five overarching themes emerge for future research to advance understanding of landscape pattern effects on ES: (1) using social-ecological measures of ES; (2) assessing ES supply, flow, and demand; (3) considering interactions among multiple drivers across scales; (4) addressing ES interactions; and (5) enhancing predictive capacity of landscape models.

Rough Around the Edges: Lessons Learned and Future Directions in Marine Edge Effects Studies Abstract Purpose of Review After several decades of research on edge effects in marine habitats, we still have little understanding of how organisms respond to marine ecotones, and methodological gaps appear to be limiting our progress. Using recent literature (2010–2018), we synthesized responses and processes of organisms across several marine habitats. Specifically, we examined the uniformity of studies across biogenic habitats, the scales selected for exploring edge effects, the experimental approaches used, and the confounding influences that muddle our interpretation of results. Recent Findings The majority of edge effect studies are still conducted in seagrass systems and focused on response patterns. We found that the majority of studies were equally likely to report an increase, decrease, neutral, or equivocal effect depending on the context of the organism or habitat. Additionally, only a single measure, or a few related responses, is assessed and causal mechanisms are rarely tested. We note that most studies quantitatively defined an edge habitat as a linear distance from a habitat boundary (e.g., < 1 m, < 5 m), but the distances were not usually scaled to the size, trophic level, or mobility of focal organisms. Summary We provide a conceptual diagram as a roadmap for researchers for navigating the myriad influences that affect floral and faunal responses to marine habitat edges. Future efforts should seek to move beyond mensurative searches, explicitly incorporate potentially confounding variables, and more consistently test putative causal factors when known or hypothesized. Additionally, we advise expanding research on habitat types other than seagrasses (e.g., mangroves, shellfish, corals) and adjusting observational scales to more appropriately match mechanisms. Ultimately, we should move beyond pattern description, repeated in a limited subset of nearshore habitats, and toward a quantitative understanding of the processes acting in these unique and potentially impactful marine ecotones.

How Integrated Ecological-Economic Modelling Can Inform Landscape Pattern in Forest Agroecosystems Abstract Purpose of Review The purpose of this review is to analyse recent advances in ecological-economic modelling designed to inform desirable landscape composition and configuration. We explore how models capture the economic and ecological consequences of landscape pattern, and potential feedbacks to the responses by policy or landholders. Recent Findings Modelling approaches are becoming increasingly interlinked, coupling components of empirical-statistical modelling, spatial and bioeconomic simulation, land-use optimization and agent-based models. We analyse recent methodological advances and find that only few examples capture feedbacks between landscape pattern and decision-making. Summary We outline how future hybrid models could build on these recent advances by inter alia an improved representation of landscape patterns, refining the theory behind decision-making, incorporating uncertainty and reducing model complexity. We conclude that coupling recent developments in land-use optimization and agent-based models may help bridge gaps between modelling philosophies as well as parsimony vs. complexity. This fruitful field of research could help to improve understanding on the role of landscape pattern in social-ecological systems.

Assessing the Relative Importance of Factors at Multiple Spatial Scales Affecting Terrestrial and Aquatic Wildlife Abstract Purpose of Review We reviewed recent studies focused on assessing the relative roles of factors operating at different scales in shaping animal populations, species, communities, and individual behaviors. Our goal was to summarize the current state of the science by documenting trends and advances in approaches used to weigh the relative impact of drivers at different scales. Recent Findings We identify several recent advances in remote sensing–based data collection, such as unmanned aerial vehicles and terrestrial laser scanning, that have the potential to increase the range of scales over which more detailed measurements of the composition and structure of environments can be made. We also highlight the promise of experimental studies and specific statistical approaches for providing a more solid understanding of the relative importance of factors operating at different spatial scales. Summary We found that after nearly three decades of studies focused on the relative importance of factors operating at different scales, no general pattern has emerged. There is no clear evidence that one scale or one set of scales consistently plays a larger role than others. Nonetheless, it is clear from this research that ecological processes are indeed affected by processes operating at multiple spatial scales. We conclude that a more productive line of questioning might focus not on the relative importance of factors operating at different scales, but on understanding which factors affect a given process, at what scales they operate, and how they interact.

Meta-analysis on a Decade of Testing Corridor Efficacy: What New Have we Learned? Abstract Purpose of Review Corridors are widely considered as a strategy to mitigate effects of habitat fragmentation on biodiversity. There are, however, lingering concerns about whether corridors work as intended and whether managing for connectivity in fragmented landscapes is even important for biodiversity conservation. In response, numerous manipulative and natural experiments have been conducted to test the effectiveness of corridors. Gilbert-Norton et al. Conserv Biol. 2010;24(3):660-8 (2010) reviewed such studies published between 1985 and 2008 and concluded that corridors are generally effective at increasing inter-patch movement. The authors noted a lack of studies measuring responses at the population and community levels, responses that would better approximate corridor effects on population persistence and aspects of biodiversity. Here I explored what new insights can be gained on corridor effectiveness from studies published in the last decade, particularly with an eye toward insights going beyond effects on inter-patch movement. Recent Findings Following the same selection criteria as Gilbert-Norton et al. Conserv Biol. 2010;24(3):660-8 (2010), I reviewed studies published between 2008 and 2018 that tested corridor effectiveness by comparing ecological response variables from patches connected and not connected by corridors. Analysis of effect sizes showed that corridors increase response variables, reinforcing earlier conclusions that corridors function as intended. Whereas the previous review mainly included corridor effects on dispersal, recent research shows support for corridor efficacy at a variety of levels of organization, from individuals to communities. Summary These findings provide further support for the conclusion that efforts spent creating and maintaining corridors are worthwhile for biodiversity conservation.

Landscape Ecology in the Rocky Intertidal: Opportunities for Advancing Discovery and Innovation in Intertidal Research Abstract Purpose of Review In this paper, I review the development of landscape-based studies in rocky intertidal communities. The rocky intertidal has served as the site of a number of influential studies in ecology that have helped demonstrate the importance of biological and physical structuring processes in nature. Owing to its ease of access and preponderance of sessile species, the intertidal has also played an important role in studies that monitor the health of coastal systems. Traditional data gathering approaches such as meter tapes and quadrats provide limited capacity to capture data at the spatial and temporal scales across which intertidal systems are currently changing. New approaches and methods are now needed to more efficiently record data across the organizational scales within which ecological processes structure the intertidal. Recent Findings Recent developments in landscape-based theory have expanded the types of research questions asked by intertidal ecologists. The subsequent incorporation of geospatial technologies into field studies that test the predictions of emerging landscape theory has revealed emergent patterns in intertidal communities and previously unrecognized relationships between species and habitat across multiple scales of ecological organization. Summary New landscape-based approaches will improve our capacity to collect and analyze data and improve quantitative inferences on how habitat complexity affects patterns of species abundance in the intertidal. The continued integration of landscape ecology into rocky intertidal research can help advance discovery science and provide a platform for bridging basic discovery science with conservation and management efforts centered about this important marine habitat.

Anthropogenic Landscape Changes and Their Impacts on Terrestrial and Freshwater Soundscapes Abstract Purpose of Review Quantifying the effects of anthropogenic sounds on wildlife at the landscape scale of observation has been notoriously difficult because these sounds are often confounded with the presence of infrastructure and loss of habitat through resource exploitation activities. In this paper, we review how anthropogenic landscape changes affect the power level and propagation of sounds in both terrestrial and freshwater ecosystems, as well as the behavioural response of organisms to novel acoustic habitats. Recent Findings Resource exploitation and other human activities change soundscapes both directly, by affecting sound production and propagation, and indirectly, by modifying landscape structure and species distribution patterns. Intermittent anthropogenic sounds are concentrated in the lower frequencies, tend to be louder than enduring sounds of the same origin and create more patchy soundscapes. We identified key sensorial traits that are related to the auditory acuity of species in different taxonomic groups, including fish, birds, anurans, stridulating insects and small mammals, and which may help us understand why certain species are more sensitive to anthropogenic changes to soundscapes. Summary Prioritizing research in an increasingly noisy world requires a proper understanding of the auditory sensitivity of species, the characteristics of anthropogenic sounds (i.e. intermittent or enduring), and how sound production and propagation is affected by landscape structure. Further research on species’ sensorial traits would provide a framework with which to scale responses to anthropogenic sounds from individuals to communities and better predict the impact of human activities on terrestrial and freshwater ecosystems.

Temporal Lag in Ecological Responses to Landscape Change: Where Are We Now? Abstract Purpose of the Review The loss or gain of biodiversity and/or ecosystem functions and services can occur with a substantial delay following landscape change. We have first revisited the key concepts used to refer to those delayed ecological responses to landscape change and then reviewed the literature aiming to summarize (i) methodological approaches used to empirically evaluate the existence of delayed ecological responses, (ii) empirical evidences of delayed ecological responses, and (iii) current understanding of the main mechanisms that can explain those delayed responses. Recent Findings We identified that key concepts used to refer to delayed ecological responses are very confusing as many different terms are used to refer to a single delayed ecological response. So, we propose here a unified vocabulary to support future research. Our review showed that there is plenty of empirical evidence that delayed ecological responses to landscape change are common in nature. However, current knowledge is mostly restricted to biodiversity responses to adverse landscape changes. Few studies have investigated for ecosystem functions and/or services delayed responses or delayed ecological gains after landscape structure improvements such as increase in habitat amount. We verified that some progress occurred in recent years. We identified the use of three new methodological approaches to empirically evaluate the existence of delayed ecological responses, and we also verified an increase in our understanding about the mechanisms that explain delayed ecological responses. As expected, we observed high levels of support for delayed ecological responses in landscapes that have undergone recent changes and for habitat specialist species. Other hypotheses have been less frequently tested. Some of them have a low level of support (no clear relationship between strength of landscape change and delayed responses), while others have a good level of support but still need more evidences (relationships between species longevity and dispersal capability with delayed responses). Summary Our understanding about delayed ecological responses to landscape change is still at an early stage and seems to be increasing slowly while human-altered landscapes are increasing rapidly worldwide. There are still important knowledge gaps to be filled. Beyond providing better support for some explanatory hypotheses, we still need to explore (1) ecosystem functions and services delayed responses to landscape change, and (2) the delayed ecological gains after positive landscape changes.

Recent Advances and Current Challenges in Applying Source-Sink Theory to Species Conservation Abstract Purpose of Review The source-sink paradigm has been a powerful tool for focusing theoretical and empirical explorations of population dynamics in heterogeneous landscapes. The prevalence of suspected source-sink dynamics in empirical studies would lead to the conclusion that sources and sinks are common. However, important questions remain about how source-sink dynamics have been assessed in past studies and the degree to which current approaches apply to atypical populations and dynamic landscapes. Recent Findings We reviewed 432 papers that directly addressed source-sink dynamics between 1985 and 2018. We found that the majority of studies focused on birds, mammals, and forested systems. In recent years, however, the number of aquatic invertebrate and marine studies increased, as did the tendency to focus on conservation or management goals and to report population trends. Although 79% of papers claimed to identify source-sink dynamics, only 13% of studies based their assessment on all four measures of reproduction, mortality, immigration, and emigration. Nearly 23% of all studies used neither demographic nor movement metrics to make conclusions about the presence of source-sink dynamics. Summary Source-sink theory and practice has matured and is increasingly relevant for species conservation and management. However, we lack a clear understanding of the conditions under which limited data can defensibly support source-sink assessments and be scaled up to the extent at which resource decisions are made. In the absence of this, future studies will need to take a more rigorous approach to defining sources and sinks to better gauge the prevalence of source-sink dynamics.