Yolanda F. Wiersma’s research while affiliated with St. John's University and other places

The movement, distribution, and relative proportions of essential elements across the landscape should influence the structure and functioning of biological communities. Yet, our basic understanding of the spatial distribution of elements, particularly bioavailable elements, across landscapes is limited. Here, we propose a quantitative framework to study the causes and consequences of spatial patterns of elements. Specifically, we integrate distribution models, dissimilarity metrics, and spatial smoothing to predict how the distribution of bioavailable elements changes with spatial extent. Our community and landscape ecology perspective on elemental diversity highlights the characteristic relationships that emerge among elements in landscapes and that can be measured empirically to help us pinpoint ecosystem control points. This step forward provides a mecha-nistic link between community and ecosystem processes. Biotic-abiotic feedbacks connect ecosystems across landscapes The distribution and relative abundance of the 25 chemical elements (see Glossary) necessary for life influence the structure and function of biological communities. However, our basic understanding of the causes and consequences of the spatial distribution of elements is limited. Historically , geological processes and abiotic factors have been the focus for predicting elemental concentrations at small, well-defined spatial extents (e.g., ponds) [1]. More recently, research has shed light on the significance of biotic ecosystem components, particularly biotic-abiotic feedback loops, on elemental distribution and abundance (Figure 1) [2-6]. Thus, the analyses of the spatial distribution of elements may be critical for forecasting the fate of biological communities in the Anthropocene. Spatial patterns of elemental abundances result from combined feedbacks of passive abiotic flows and biotic ecosystem components (e.g., animal deposition of materials) acting at different spatial and temporal scales (Figure 1). At a broad spatial extent, weathering of bedrock builds an elemental pool that is then distributed via abiotic and biotic processes [7]. At smaller spatial extents, abiotic processes, such as the mixing of nutrient-rich ground water and nutrient-poor surface water, create local elemental hotspots or elemental coldspots of inorganic nitrogen (N) [8,9]. These hotspots of N can then get redistributed via abiotic and biotic processes, including daily movements of organisms (Figure 1). At small spatial extents, animals with relatively small home ranges (e.g., snowshoe hares, Lepus americanus, or Arctic foxes, Vulpes lagopus), may contribute to localized elemental hotspots [10], such as the build-up of nutrients around Arctic fox den sites [11]. Biotic processes can also operate at larger spatial scales. For example, moose (Alces alces) home ranges include a diversity of habitats, including early successional forests used for foraging and mature forests used for shelter. Selective herbivory by moose in foraging patches removes nutritious understory plants with relatively high N and P content [12]. Highlights Complex biotic and abiotic feedbacks affect the spatial distribution of the 25 elements necessary for life, but most studies focus on only biotic or abiotic components at small spatial extents. Plants and animals not only affect, but also respond to the distribution and stoichiometry of elements; thus, understanding geodiversity is critical to improve our understanding of species distributions and ecosystem function. Meta-ecosystem theory has already started to demonstrate how the feedback between biotic and abiotic components of ecosystems can impact community structure and function; however, we need an empirical parallel. Here, we propose a framework that applies tools from community and landscape ecology to study and analyze spatial scaling of elements across landscapes. This will allow us to quantify how spatial patterns in elements vary across spatial scales.

The island of Newfoundland, Canada, is known as an area with high lichen species richness; however, most of this diversity is known from coastal regions where the ocean creates a maritime climate. The central part of the island has a more continental climate and is also the part of the province with the highest levels of industrial forest harvest and mining activities. For these reasons, it has not been an area considered to have high lichen diversity. Here, we show how local Mi'kmaw knowledge in collaboration with western scientific expertise facilitated a two-eyed seeing approach (Etuaptmumk) that yielded the discovery of overlooked lichen diversity in Central Newfoundland. Surveys by the authors throughout 2023 yielded collections of 175 species of lichenized, lichenicolous and allied fungi from the area known as Charlie's Place. Of these, there is a high proportion of cyanolichens (13%) and calicioids (11%), indicating high ecological value and potential old growth/ancient forest status. In addition, we report 19 new species records for the province, two of which (Chaenothecopsis vainioana and Myrionora albidula) are new records for Canada. Overall, the survey work reported here suggests that Charlie's Place should be a priority area for protection within the context of Central Newfoundland. This work also illustrates the value of research under the framework of Etuaptmumk and the benefits of combining local Indigenous and western scientific knowledge. The political, logistical, and financial support of Qalipu First Nation was key to the success of this work

Citizen science projects that collect natural history observations often do not have an underlying research question in mind. Thus, data generated from such projects can be considered "use-agnostic." Nevertheless, such projects can yield important insights about species distributions. Many of these projects use a class-based data schema, whereby contributors must supply a species identification. This can limit participation if contributors are not confident in their identifications, and can introduce data quality issues if species identification is incorrect. Some projects, such as iNaturalist, circumvent this with crowdsourced species identifications based on contributed photographs, or by grading confidence in the data based on attributes of the sighting and/or contributor. An alternative to a class-based data schema is an open-ended (instance-based) one, where contributors are free to identify their sighting at whatever taxonomic resolution they are most confident, and/or describe the sighting based on attributes. This can increase participation (data completeness) and have the benefit of adding additional (and sometimes unexpected) information. The regionally-focused citizen science website NLNature.com was designed to experimentally examine how class-based versus instance-based schema affected contributions and data quality. Here, we show that the instance-based schema yielded not only more contributions, but also several of ecological importance. Thus, allowing contributors to supply natural history information at a level familiar to them increases data completeness and facilitates unanticipated contributions.

Organisms move across landscapes mediating nutrient, energy, and biomass exchanges. Meta-ecosystem ecology offers a framework to study how these flows affect ecosystem functions in space and time. However, meta-ecosystem models often represent consumer movement as diffusion along gradients of resources. Crucially, this assumes that consumer movement connects the same trophic compartments among patches of the same ecosystem. Yet, empirical evidence shows that organisms move across different ecosystems and connect diverse trophic compartments in diffusive and non-diffusive ways. Here, we derive a two-patch meta-ecosystem model that accounts for both types of organismal movement, and we investigate their influences on local and meta-ecosystem functions. We apply a novel approach, modelling consumer movement through a dispersers’ pool that captures the fraction of moving organisms and allows us to partition local and regional dynamics. We show that non-diffusive consumer movement increases landscape heterogeneity while diffusive consumer movement enhances source–sink dynamics. Local ecosystem differences driven by consumer movement type are less prevalent at meta-ecosystem extents. Thus, movement type is essential for predicting local ecosystem dynamics. Our results support recent calls to consider explicitly the role of consumers in shaping and maintaining ecosystem functions across spatial extents.

The contemporary rate of environmental change is faster than ever recorded. Wildlife will need to acclimate or adapt habitat selection strategies to persist in the face of rapid natural and anthropogenic change. We reviewed primary literature on cumulative effects and habitat selection frameworks that link to functional response. Our primary goal was to highlight how functional response to habitat selection can fit into current approaches that assess wildlife response to landscape disturbance including model structure, disturbance type, and spatiotemporal scales. Both functional response to habitat selection and cumulative effects assessment endeavor to capture how wildlife alter their space use across a changing landscape over time. These two methods are seldom used in combination, but together can quantify behavioral responses that may change as a function of accumulating disturbances. Most studies we reviewed included multiple measures of anthropogenic disturbance, but rarely considered how the interaction between separate disturbances may influence wildlife response. We propose integrating functional response to habitat selection and cumulative effects using resource selection functions. We identify three avenues to further expand the use of this application: (A) considering different types of cumulative effects and their interactions, (B) predicting responses over space and time, and (C) using thresholds as a path to understand biological mechanisms. Allowing disturbance responses to covary as a function of resource availability will provide meaningful comparisons of habitat selection and aid in disentangling cumulative effects interactions.

Species-focused conservation requires a thorough understanding of species’ distributions. Delineating a species’ distribution requires taxonomic knowledge and adequate occurrence data. For plants and fungi, herbaria represent a valuable source of large-scale occurrence data. Advances in digital technology mean that data from many herbarium collections worldwide are now easily accessible. However, species concepts can change over time requiring herbarium records to be re-examined and databases updated, which does not always occur synchronously across all collections. Therefore, non-critical use of these data can promote inaccuracies in understanding species distributions. Taxonomic revisions are common in understudied organisms, such as lichens. Here, we illustrate how changing taxonomy and non-critical acceptance of online data affects our understanding of disjunct distributions, using the lichen Brodoa oroarctica (Krog) Goward as an example. Defining the distribution of the arctic lichen B. oroarctica is confounded by changing taxonomy and uncertainty of herbarium records that pre-date taxonomic revisions. We review the distribution of this species in the literature and in aggregate occurrence databases, and verify herbarium specimens that represent disjunct occurrences in eastern North America to present an updated account of its distribution and frequency in eastern North America. We show that knowledge of changing species taxonomy is essential to depicting accurate species distributions.

FIPEX v10.4 is designed to decrease the time required to assess the individual and cumulative effects of river barriers to fish passage and to assess river connectivity from headwaters to outflow (i.e., longitudinal connectivity) Loss of longitudinal connectivity due to anthropogenic barriers is a global problem contributing to unprecedented biodiversity loss in freshwater biomes. Yet, assessing longitudinal connectivity from the perspective of fish and prioritizing ecological restoration is challenging without specialized tools. The Fish Passage Extension (FIPEX) v10.4 is designed to bridge network analysis and Geographic Information System (GIS) in support of river connectivity assessments. It is developed as an open source VB.NET ‘Add-In’ for ArcGIS Desktop (v10.4+) with an option to run R statistical software scripts to calculate the Dendritic Connectivity Index (DCI).

Organisms moving across landscapes connect ecosystems in space and time, mediating nutrient, energy, and biomass exchanges. Meta-ecosystem ecology offers a framework to study how these flows affect ecosystem functions in space and time. However, meta-ecosystem models often represent consumer movement as diffusion along gradients of resources. Crucially, this assumes that consumer movement connects the same trophic compartments among patches of the same ecosystem. Yet, empirical evidence shows that organisms move across different ecosystems and connect diverse trophic compartments in diffusive and non-diffusive ways. Here, we derive a two-patch meta-ecosystem model that accounts for both types of organismal movement, and we investigate their influences on local and meta-ecosystem functions. We integrate two novel approaches in this classic meta-ecosystem model: a dispersers' pool to capture the fraction of moving organisms and time scales separation to partition local and regional dynamics. We show that non-diffusive consumer movement increases landscape heterogeneity while diffusive consumer movement enhances source-sink dynamics. Local ecosystem differences driven by consumer movement type are less prevalent at meta-ecosystem extents. Thus, movement type is essential for predicting local ecosystem dynamics. Our results support recent calls to explicitly consider the role of consumers in shaping and maintaining ecosystem functions in space and time.

Approximatively 25 chemical elements are essential for the maintenance, growth and reproduction of all living organisms. Hence, the movement, distribution, and relative proportions of those elements on the landscape should have significant influence on the structure and functioning of biological communities. Yet our basic understanding for the spatial distribution of elements across landscapes and the drivers of those patterns are limited. Here, we propose a novel framework to apply tools from community and landscape ecology to study spatial patterns in elements. We illustrate this framework with an empirical proof of concept in the boreal forest and demonstrate how spatial grain and spatial dissimilarity of elements interact leading to predictable patterns in elemental distributions at various spatial scales. In particular, we observe that at finer spatial grains, sites with high contributions to elemental dissimilarity cluster together. As grain size increases, the landscape becomes more homogeneous with larger patches of sites with intermediate contributions to elemental dissimilarity emerging near aquatic-terrestrial boundaries. Meanwhile, an analysis revealed that the most important elemental contributors to spatial dissimilarity in this landscape are potassium and calcium, two infrequently studied elements in community ecology, raising new questions about their role in, or response to, distributions of biodiversity and ecosystem functions. Our novel framework demonstrates how we can use community metrics (e.g., dissimilarity) to investigate variability of individual elements, the building blocks of stoichiometric ratios, across landscapes. As a field, ecology is just beginning to fully acknowledge the contribution of biotic factors in shaping biogeochemical processes, but here we provide a framework for integrating abiotic and biotic processes. We conclude by hypothesizing that changes in the evenness or beta-diversity of elements should reflect the structure of biotic communities, providing a long-sought mechanistic link between community and ecosystem processes that can be measured directly in the field.