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1. Changes in natural land cover have been pronounced in the last 12,000 years, and land use has intensified in the last century owing to anthropogenic pressures on landscapes. This trend has led to concomitant changes in the abiotic templates and biotic communities of different ecosystems embedded in a landscape. 2. Deciphering the role of land use is key to understand ecological change in boreal landscapes. These landscapes are characterized by large numbers of lakes that have been affected by various anthropogenic factors, of which land use has considerable direct and indirect effects on lakes. 3. In this review, we focus on land use impacts on boreal lakes in a historical perspective. We will consider lake features related to abiotic conditions, biological communities and ecosystem services, and provide potential solutions for planning lake management and conservation in a landscape setting. More specifically, we propose a novel way to characterize lake abiotic, biotic and ecosystem service features by applying the alpha, beta and gamma concept used widely in ecological research. 4. Finally, we highlight situations where this approach could be a valuable addition to existing means to identify lakes that should be reserved for ecosystem services (‘lake-sharing’) and those that are vital for protecting aquatic biodiversity (‘lake-sparing’).

Unravelling patterns and mechanisms of biogeographical transitions is crucial if we are to understand compositional gradients at large spatial extents, but no studies have thus far examined breakpoints in community composition of freshwater plants across continents. Using a dataset of almost 500 observations of lake plant community composition from six continents, we examined, for the first time, if such breakpoints in geographical space exist for freshwater plants and how well a suite of ecological factors (including climatic and local environmental variables) can explain transitions in community composition from the subtropics to the poles. Our combination of multivariate regression tree (MRT) analysis and k-means partitioning suggests that the most abrupt breakpoint exists between temperate to boreal regions on the one hand and freshwater plant communities harbouring mainly subtropical or Mediterranean assemblages on the other. The spatially structured variation in current climatic conditions is the most likely candidate for controlling these latitudinal patterns, although one cannot rule out joint effects of eco-evolutionary constraints in the harsher high-latitude environments and post-glacial migration lags after Pleistocene Ice Ages. Overall, our study supports the foundations of global regionalisation for freshwater plants and anticipates further biogeographical research on freshwater plant communities once datasets have been harmonised for conducting large-scale spatial analyses.

Context: Recent studies show that geodiversity—the diversity of Earth’s landforms, materials, and processes—has a positive relationship with biodiversity at a landscape scale. However, there is a substantial lack of evidence from finer scales, although this knowledge could improve the understanding of biodiversity patterns. Objectives: We investigate whether plot-scale geodiversity and plant species richness (vascular plants, bryophytes, lichens, and total richness) are positively linked in different tundra landscapes. Methods: We collected geodiversity (presence of different geofeatures) and plant species richness data from 165 sites in three distinct regions: isolated low-lying mountain heaths, and in sporadic and continuous mountain heaths and tundra. We used non-metric multidimensional scaling (NMDS) ordination to explore the correlations between the composition of geofeatures and species richness, followed by univariate and multivariate generalized linear models (GLM), to assess whether georichness is important for species richness. Results: Geofeature composition was linked to species richness in all regions, as indicated by NMDS ordination. Both univariate and multivariate GLM models showed statistically significant relationship between species richness and georichness in all studied species richness groups in continuous Arctic-alpine tundra. Additionally, there was a positive link between georichness and lichen richness in isolated boreal mountain tops. Main conclusions: We showed that plot-scale geodiversity has a positive relationship with species richness, yet the effect varies regionally and between species groups. Our study provides strong empirical evidence that geodiversity supports species richness in continuous Arctic-alpine tundra. This information can be used in species richness models but also be applied in biodiversity management and conservation.

Biodiversity conservation through protected areas (PAs) is often based on the idea that biodiversity is relatively static. This assumption is increasingly being challenged as species and communities shift their distributions in response to changing environmental conditions. Empirical evidence on the performance of PAs over decades is still sparse or lacking from several environments, although it is needed to understand species dynamics, support modelling of PA performance, assist PA management and ultimately, to achieve global biodiversity conservation goals. In 2021, we resurveyed vegetation of five boreal habitat types (heath forests, paludified forests, sun-exposed sites, mires and eulittoral sites) in Rokua National Park in Finland, where one of the conservation targets is to preserve the flora characteristic of the area. The study sites were originally surveyed in 1945‐49, just before the National Park was established. Study sites have also remained free from the disturbances (forest fires and reindeer grazing) typical of boreal regions. We show that the compositional similarity of plant communities between habitat types has increased over time and is associated with the increase of forest species in several habitat types and the loss of many habitat-specific species. Drivers of change were most often linked to ongoing succession (understory closure) and changes in moisture conditions. Our results suggest that without natural disturbance or appropriate management efforts, the original conservation targets may be compromised over the decades. Our study demonstrates that resurvey of historical vegetation data can be effectively used to estimate long-term PA performance, helping to fill in missing temporal evidence.

Aim: The regionalized patterns of biodiversity distributions are actively studied in terrestrial and marine ecosystems, but much less is known on the geographical patterns of ecoregions founded on freshwater taxa. Here, we studied, for the first time, how well existing freshwater ecoregions describe the geographical distribution of inland water plants. Location: Greenland, continental Canada and USA. Taxon: Freshwater vascular plants of all taxa and multiple functional groups (i.e. growth forms). Methods: Using newly available fine-grained data on freshwater plant distributions, we studied how ecoregions founded on fish are suitable for freshwater plant regionalization across North America. Specifically, we calculated internal homogeneity and distinctness among neighbouring ecoregions in relation to species replacements and richness differences. We also explored how a complex suite of ecogeographical characteristics affect ecoregion delineation of freshwater plants using spatially explicit regression routines. Results: We found a clear geographical patterning of ecoregion robustness for North American freshwater plants, with communities being more internally homogeneous and more similar to one another in Polar and Subtropical inland waters. The degree of internal homogeneity and ecoregion distinctness were almost equally driven by species replacements and richness differences. Considering different life-forms, ecoregion delineation performed best for emergent and floating-leaved plants. Finally, within-ecoregion homogeneity and distinctness were best explained by annual mean temperature and terrain ruggedness, respectively, with mean water alkalinity, ecoregion area and late Quaternary glacial legacies having supplementary effects. Main conclusions: Our findings suggest that selection through climate filtering (e.g. mean annual temperature) is likely the main mechanistic driver of freshwater plant ecoregions. Geographical regionalizations founded on a parti

It has long been debated why groups such as non-avian dinosaurs became extinct whereas mammals and other lineages survived the Cretaceous/Paleogene mass extinction 66 million years ago. We used Markov networks, ecological niche partitioning, and Earth System models to reconstruct North American food webs and simulate ecospace occupancy before and after the extinction event. We find a shift in latest Cretaceous dinosaur faunas, as medium-sized species counterbalanced a loss of megaherbivores, but dinosaur niches were otherwise stable and static, potentially contributing to their demise. Smaller vertebrates, including mammals, followed a consistent trajectory of increasing trophic impact and relaxation of niche limits beginning in the latest Cretaceous and continuing after the mass extinction. Mammals did not simply proliferate after the extinction event; rather, their earlier ecological diversification might have helped them survive.

Summary Our existence on Earth is founded on a vital nature, which supports human physical and mental health. However, nature is often depicted only through biodiversity, whereas geodiversity—the diversity of non-living nature—has so far been neglected. Geodiversity consists of assemblages, structures, and systems of geological, geomorphological, soil, and hydrological components that fundamentally underlie biodiversity. Biodiversity can support overall human health only with the foundation of geodiversity. Landscape characteristics, such as varying topography or bodies of water, promote aesthetic and sensory experiences and are also a product of geodiversity. In this Personal View, we introduce the concept of geodiversity as a driver for planetary health, describe its functions and services, and outline the intricate relationships between geodiversity, biodiversity, and human health. We also propose an agenda for acknowledging the importance of geodiversity in health-related research and decision making. Geodiversity is an emerging topic with untapped potential for ensuring ecosystem functionality and good living conditions for people in a time of changing environments.

Geodiversity is an emerging, multi-faceted concept in Earth and environmental sciences. Knowledge on geo-diversity is crucial for understanding functions of natural systems and in guiding sustainable development. Despite the critical nature of geodiversity information, data acquisition and analytical methods have lagged behind the conceptual developments in biosciences. Thus, we propose that geodiversity research could adopt the framework of alpha, beta and gamma concepts widely used in biodiversity research. Especially, geodiversity research would benefit from widening its scope from the evaluation of individual sites towards more holistic geodiversity assessments, where between-site geodiversity is also considered. In this article, we explore the alpha, beta and gamma concepts and how they can be applied in a geodiversity framework. In addition, we scrutinize the statistical methodology related to alpha, beta and gamma geodiversity evaluations, with a special focus on distance metrics for measuring beta geodiversity. As an overview of the process, and to give practical guidelines for the application of the proposed methodology, we present a case study from a UNESCO Global Geopark area. Thus, this study not only develops the geodiversity concept, but also paves the way for simultaneous understanding of both geodiversity and biodiversity within a unified conceptual approach.

Current global environmental change calls for comprehensive and complementing approaches for biodiversity conservation. According to recent research, consideration of the diversity of Earth’s abiotic features (i.e. geodiversity) could provide new insights and applications into the investigation and management of biodiversity. However, methods to map and quantify geodiversity at local scale have not been developed although this scale is important for conservation planning. Here, we introduce a field methodology for observing plot-scale geodiversity, pilot the method in an Arctic–alpine tundra environment, provide empirical evidence on the plot-scale biodiversity–geodiversity relationship and give guidance for practitioners on the implementation of the method. The field method is based on observation of geofeatures, that is, elements of geology, geomorphology and hydrology, from a given area surrounding a location of species observations. As a result, the method provides novel information on the variation of abiotic nature for biodiversity research and management. The method was piloted in northern Norway and Finland by observing geofeatures from 76 sites at three scales (5, 10 and 25 m radii). To explore the relationship between measures of biodiversity and geodiversity, the occurrence of vascular plant species was recorded from 2 m × 2 m plots at the same sites. According to the results, vascular plant species richness was positively correlated with the richness of geofeatures (Rs = 0.18–0.59). The connection was strongest in habitats characterized by deciduous shrubs. The method has a high potential for observing geofeatures without extensive geological or geomorphological training or field survey experience and could be applied by conservation practitioners. Synthesis and applications. Consideration of geodiversity in understanding, analysing and conserving biodiversity could facilitate environmental management and ensure the long-term sustainability of e

Community ecology has had a strong focus on single snapshots of species compositional variation in time. However, environmental change often occurs slowly at relatively broad spatio-temporal scales, which requires historically explicit assessments of long-term metacommunity dynamics, such as the order of species arrival during community assembly (i.e., priority effects), a theme that merits further empirical quantification. In this study, we applied the Bayesian inference scheme of Hierarchical Modeling of Species Communities together with information on functional traits and evolutionary dependencies to efficiently explore the question of how ecological communities are organized in space and time. To do this, we used a comprehensive time-series dataset from boreal lake plants and adopted the perspective that more sound conclusions on metacommunity dynamics can be gained from studies that consider a historically integrative approach over long timeframes. Our findings revealed that historical contingency via priority effects can profoundly shape community assembly under the influence of environmental change across decades (here, from the 1940s to the 2010s). Similarly, our results supported the existence of both positive and negative species-to-species associations in lake plants, suggesting that functional divergence can switch the inhibition–facilitation balance at the metacommunity level. Perhaps more importantly, this proof-of-concept study supports the notion that community ecology should include a historical perspective and suggests that ignoring priority effects may risk our ability to identify the true magnitude of change in present-day biotic communities.

Patterns of species rarity have long fascinated ecologists, yet most of what we know about the natural world stems from studies of common species. A large proportion of freshwater plant species has small range sizes and are therefore considered rare. However, little is known about the mechanisms and geographical distribution of rarity in the aquatic realm and to what extent diversity of rare species in freshwater plants follows their terrestrial counterparts. Here, we present the first in–depth analysis of geographical patterns, potential deterministic ecogeographical factors and projected scenarios of freshwater vascular plant rarity using 50 × 50 km grid cells across Europe (41°N–71°N) and North America (25°N–78°N). Our results suggest that diversity of rare species shows different patterns in relation to latitude on the two continents, and that hotspots of rarity concentrate in a relatively small proportion of the European and North American land surface, especially in mountainous as well as in climatically rare and stable areas. Interestingly, we found no differences among alternative rarity definitions and measures when delineating areas with notably high diversity of rare species. Our findings also indicate that few variables, namely a combination of current climate, Late Quaternary climate–change velocity and human footprint, are able to accurately predict the location of continental centers of rare species diversity. However, these relationships are not geographically homogeneous, and the underlying factors likely act synergistically. Perhaps more importantly, we provide empirical evidence that current centers of rare species diversity are characterized by higher anthropogenic impacts and might shrink disproportionately within this century as the climate changes. Our reported distributional patterns of species rarity align with the known trends in species richness of other freshwater organisms and may help conservation planners make informed decisio

Documenting the patterns and potential associated processes of ancient biotas has always been a central challenge in palaeontology. Over recent decades, intense debate has focused on the organization of dinosaur-dominated communities, yet no general consensus has been reached on how these communities were organized in a spatial context. Here, we used analytical routines typically applied in metacommunity ecology to provide novel insights into dinosaurian distributions across the latest Cretaceous of North America. To do this, we combined fossil occurrences with functional, phylogenetic and palaeoenvironmental modelling, and adopted the perspective that more reasonable conclusions on palaeoecological reconstructions can be gained from studies that consider the organization of biotas along ecological gradients at multiple spatial scales. Our results showed that dinosaurs were restricted in range to different parts of the Hell Creek Formation, prompting the recognition of discrete and compartmentalized faunal areas during the Maastrichtian at fine-grained scales, whereas taxa with the broadest ranges included those with narrower distributions when combining data from various geological formations across the Western Interior of North America. Although groups of dinosaurs had coincident range boundaries, their communities responded to multiple ecologically-important gradients when compensating for differences in sampling effort. Metacommunity structures of both ornithischians and theropods were correlated with climatic barriers and potential trophic relationships between herbivores and carnivores, thereby suggesting that dinosaurian faunas were shaped by physiological constraints, limited food resources abundance, and a combination of bottom-up and top-down forces across multiple spatial grains and extents.

Broad-scale studies of species distributions and diversity have contributed to the emergence of general macroecological rules. These rules are typically founded on research using well-known terrestrial taxa as models and it is thus uncertain whether aquatic macrophytes follow these macroecological rules. Our purpose is to draw together available information from broad-scale research on aquatic macrophytes growing in lakes, ponds, wetlands, rivers and streams. We summarize how different macroecological rules fit the patterns shown by freshwater plants at various spatial scales. Finally, we outline future actions which should be taken to advance macroecological research on freshwater plants. Our review suggested that some macroecological patterns are relatively well-evidenced for aquatic macrophytes, whereas little information exists for others. We found, for example, that the species richness-latitude relationship follows a unimodal pattern, and species turnover prevails over species nestedness, whereas higher nestedness-related richness differences are found in low beta diversity regions. Contrary to terrestrial plants, climate or history seem not to be dominant determinants explaining these broad-scale patterns; instead local explanatory variables (e.g., water quality, such as alkalinity and nutrients, and hydromorphology) are often important for freshwater plants. We identified several knowledge gaps related, for example, to a smaller number of studies in lotic habitats, compared with lentic habitats, lack of spatially-adequate aquatic plant studies, deficiency of comprehensive species traits databases for aquatic macrophytes, and absence of a true phylogeny comprising most freshwater plant lineages. We hope this review will encourage the undertaking of additional macroecological investigations on freshwater plants across broad spatial and temporal scales.

1. To comprehensively understand the impact of anthropogenic activities on biodiversity, we must understand how biodiversity has changed over time and what are the underlying processes. A growing body of evidence has shown that beta diversity reveals more about temporal changes in biodiversity compared with alpha diversity. Temporal beta diversity indicates, for example, degrees of change in species composition at single locations through time. 2. We examined whether freshwater plant communities showed different patterns in temporal beta diversity in relation to concomitant changes in environmental conditions across decades. To do this, we used presence–absence data of lake plants for five decades (1940s–2010s) from southern Finland and calculated temporal beta diversity indices (TBI) for each lake between pairs of decades to the whole community, hydrophytes and helophytes. To get insights into possible processes behind the observed trends, we decomposed TBIs into beta diversity contributed by either temporal losses or temporal gains of species. We related TBIs and their loss and gain components to lake landscape position and changes in environmental variables. 3. Based on comparisons of TBIs between the survey decade pairs, the temporal change in aquatic plant communities was modest through decades. Hydrophyte assemblages have changed more than helophyte assemblages. The main changes in temporal beta diversity occurred from the 1940s to the 1970s, when the gain of new species was the dominant process in the lakes throughout the landscape. Following that period, there was only modest changes, but from the 2000s to the 2010s, the dominant process was the loss of species. Temporal changes in environmental conditions played a key role in explaining the TBI. 4. Our results showed that relying on only two survey points in time can result in limited knowledge of the ecological phenomenon under study and, for example, an exceptional year in terms of weather condit

Aim: Range size conservatism suggests that closely-related species maintain geographic ranges of similar extent. However, consensus regarding this suggestion has not been reached. To shed more light on this phenomenon, we studied freshwater plant range size conservatism, range overlap and environmental niche conservatism using congeneric species comparison in two continents. In addition, we investigated whether a phylogenetic signal is found in the range sizes of aquatic plants. Location: Europe and North America. Taxon: Freshwater plants. Methods: Across spatial resolutions (50 km², 100 km² and 200 km²), we applied Spearman correlations among 347 and 730 pairs of congeneric species in Europe and North America, respectively, and 63 pairs shared between them. In addition, Spearman correlations were used to evaluate how the degree of spatial overlap influences range sizes and which environmental variables explain variation in range sizes. Brownian evolutionary model was used to assess the phylogenetic signal in species range sizes. Results: We found no evidence of range size conservatism across spatial resolutions for any species and species shared between the continents. In addition, range sizes of more closely related species did not overlap geographically more than those of distantly related ones and no support for environmental niche conservatism was evidenced. Main conclusions: We found that aquatic plants show no range size conservatism in the Northern Hemisphere. This means that it is challenging to define different range sizes of freshwater plants through species traits. Furthermore, we are unable to predict unknown distributions of extant aquatic plant species based on known distributional attributes of closely related species. However, our findings suggest that the interpretations of previous investigations on the range sizes of aquatic plants remain valid due to lack of range size conservatism. These practical implications encourage studying range

To comprehensively understand the impact of anthropogenic activities on biodiversity, we must understand how biodiversity has changed over time and its underlying processes. Regardless of a recent increase in scientific interest towards changes in community composition, i.e. beta diversity, these changes have not been studied comprehensively in lake environments in a spatio-temporal framework. In addition, although biotic homogenisation has gained much attention in recent decades, it is still unclear how this process acts at different levels of biodiversity through time. The main aim of this thesis is to study temporal and spatial biodiversity patterns of vascular aquatic macrophyte communities in small boreal lakes during a period of 70 years. The focus is on beta diversity-environment relationships and different dimensions of biodiversity, with special attention to functional features. This thesis is based on three separate case studies that all have utilised temporal presence-absence data of vascular aquatic macrophytes from 27 to 28 lakes from the 1940s to the 2010s. Vascular aquatic macrophyte communities showed only moderately different spatial beta diversity patterns in relation to human impact across decades. The patterns of different dimensions of spatial beta diversity diverged only slightly from each other. The temporal change in aquatic macrophyte communities at the lake level has been modest since the 1940s. Nevertheless, it seems that even relatively modest changes in the environment affect temporal gains and losses of species at the lake level. There were no signs of either biotic homogenisation or biotic differentiation (taxonomic, phylogenetic or functional), but the changes in the environment have affected functional community composition and changes in functional richness to some extent. By using the spatial and temporal beta diversity perspective, this thesis highlights the fact that even though biotic homogenisation is a pervasive probl

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Documenting the patterns of biological diversity on Earth has always been a central challenge in macroecology and biogeography. However, for the diverse group of freshwater plants, such research program is still in its infancy. Here, we examined global variation in taxonomic, functional and phylogenetic beta diversity patterns of lake macrophytes using regional data from six continents. A data set of ca. 480 lake macrophyte community observations, together with climatic, geographical and environmental variables, was compiled across 16 regions worldwide. We (a) built the very first phylogeny comprising most freshwater plant lineages; (b) exploited a wide array of functional traits that are important to macrophyte autoecology or that relate to lake ecosystem functioning; (c) assessed if different large-scale beta diversity patterns show a clear latitudinal gradient from the equator to the poles using null models; and (d) employed evolutionary and regression models to first identify the degree to which the studied functional traits show a phylogenetic signal, and then to estimate community-environment relationships at multiple spatial scales. Our results supported the notion that ecological niches evolved independently of phylogeny in macrophyte lineages worldwide. We also showed that taxonomic and phylogenetic beta diversity followed the typical global trend with higher diversity in the tropics. In addition, we were able to confirm that species, multi-trait and lineage compositions were first and foremost structured by climatic conditions at relatively broad spatial scales. Perhaps more importantly, we showed that large-scale processes along latitudinal and elevational gradients have left a strong footprint in the current diversity patterns and community-environment relationships in lake macrophytes. Overall, our results stress the need for an integrative approach to macroecology, biogeography and conservation biology, combining multiple diversity facets at d

Documenting the patterns of biological diversity on Earth has always been a central challenge in macroecology and biogeography. However, we are only beginning to generate an understanding of the global patterns and determinants of macrophyte diversity. Here, we studied large-scale variation and community-environment relationships of lake macrophytes along climatic and geographical gradients using regional data from six continents. We applied statistical routines typically used in the context of metacommunity studies to provide novel insights into macrophyte community compositional patterns within regions worldwide. We found that lake macrophyte metacommunities followed clumped species replacement structures, suggesting that two or more species groups were responding similarly to the environment within regions. Underlying such general convergence, our results also provided evidence that community-environment relationships were largely context-dependent, stressing that no single mechanism is enough to account for the complex nature of compositional variation. Surprisingly, we found no general relationships between functional or phylogenetic composition and main metacommunity types, suggesting that linking multi-trait and evolutionary information to the elements of metacommunity structure is not straightforward. Our findings highlight that global conservation initiatives and biodiversity protection need to capture environmental variation at the metacommunity level, and acknowledge the highly context-dependent patterns in the community-environment relationships of lake macrophytes. Overall, we emphasize the need to embrace the potential complexity of ecological inferences in metacommunity organization across the globe.

1. The latitudinal diversity gradient hypothesis suggests that species richness should be highest at low latitudes, whereas Rapoport’s rule states that largest ranges ought to be found for species at high latitudes. However, there is no consensus over these patterns and their underlying drivers in the freshwater realm. 2. We investigated species richness and mean range size of freshwater plants in 50 × 50 km grid cells across Europe (40°N–71°N) and North America (25°N–78°N), supplemented with data based on 1° latitudinal bands for mean range size. We were especially interested to find out whether there are similarities and differences in these ecogeographical patterns and their underlying drivers between the continents due to their contrasting historical characteristics, spatial extent and topography. 3. First, we used partial regression to reveal whether species richness and mean range size of freshwater plants have a linear or quadratic relationship with latitude. Second, we employed variation partitioning based on partial regression to model relationships between plant species richness and mean range size and four explanatory variable groups (i.e. environmental features, current climate, historical climate and geographical location). Third, we utilized boosted regression tree analysis to further investigate species richness and mean range size of freshwater plants in relation to a set of explanatory variables. 4. Our results revealed that species richness showed relatively similar patterns in relation to latitude between the continents. Similarly, mean range size trends were alike in North America whether we used 50 × 50 km grid cell data or 1° latitudinal bands. Instead, different patterns in mean range size emerged between the used datasets in Europe. For both species richness and mean range size, current climate (with different individual predictor variables) was the main driver in both the continents, but historical effects had a small influence on t

Biotic interactions are fundamental drivers governing biodiversity locally, yet their effects on geographical variation in community composition (i.e. incidence‐based) and community structure (i.e. abundance‐based) at regional scales remain controversial. Ecologists have only recently started to integrate different types of biotic interactions into community assembly in a spatial context, a theme that merits further empirical quantification. Here, we applied partial correlation networks to infer the strength of spatial dependencies between pairs of organismal groups and mapped the imprints of biotic interactions on the assembly of pond metacommunities. To do this, we used a comprehensive empirical dataset from Mediterranean landscapes and adopted the perspective that community assembly is best represented as a network of interacting organismal groups. Our results revealed that the co‐variation among the beta diversities of multiple organismal groups is primarily driven by biotic interactions and, to a lesser extent, by the abiotic environment. These results suggest that ignoring biotic interactions may undermine our understanding of assembly mechanisms in spatially extensive areas and decrease the accuracy and performance of predictive models. We further found strong spatial dependencies in our analyses which can be interpreted as functional relationships among several pairs of organismal groups (e.g. macrophytes–macroinvertebrates, fish–zooplankton). Perhaps more importantly, our results support the notion that biotic interactions make crucial contributions to the species sorting paradigm of metacommunity theory and raise the question of whether these biologically‐driven signals have been equally underappreciated in other aquatic and terrestrial ecosystems. Although more research is still required to empirically capture the importance of biotic interactions across ecosystems and at different spatial resolutions and extents, our findings may allow decision

Ecosystems support human existence and well-being through supply of services such as food, materials and energy flows, and by opportunities for cultural experiences. These are called ecosystem services (ES). There is a growing body of literature that recognizes also ecosystem functions which do not provide benefits to humans. These ecosystem drawbacks, namely ecosystem disservices (EDS), cause negative effects on human well-being. In both cases, most ES and EDS exist only if there is transfer of goods and (dis)services to people. However, there is often a spatial discrepancy between places where ES or EDS are produced and the location where people use or are exposed to them, which is a major challenge in the assessment and mapping of ES and EDS. Therefore, spatially explicit information on the geographical connections between the ES or EDS supply and demand areas is essential, and sustainable utilization possibilities of services are flawed without this knowledge. In this thesis, the transfer of services or disservices from ecosystems to people across an area was addressed using the concept of spatial accessibility, which determines how easily a location can be reached from another location or the potential for reaching geographically distributed opportunities. The main aim was to investigate the applicability of the Geographic Information System-based accessibility approach in ES and EDS mapping. This thesis consists of three separate studies, of which each one tested the approach using different sets of ES and EDS indicators at different spatial scales. The first study assessed the availability and access of cultural ES in Finland, the second the balance between food ES supply and demand across Europe and the third the suitability of the accessibility methods for measuring the negative effects of disease vectors on Finnish people. The goals of these studies were to increase the understanding of people’s ability to utilize different ES and estimate the neg

We investigated whether environmental filtering or dispersal-related factors mostly drive helophyte and hydrophyte species richness and community composition in 93 lakes situated in Baikal Siberia. Using partial linear regression and partial redundancy analysis, we studied (1) what are the relative roles of environmental variables, dispersal variables, spatial processes and region identity (i.e., river basins) in explaining variation in the species richness and species composition of helophytes and hydrophytes across 93 Siberian lakes, and (2) what are the differences in the most important explanatory variables driving community variation in helophytes versus hydrophytes? We found that, for both species richness and species composition, environmental variables clearly explained most variation for both plant groups, followed by region identity and dispersal-related variables. Spatial variables were significant only for the species composition of hydrophytes. Nutrient-salinity index, a proxy for habitat trophic-salinity status, was by far the most significant environmental determinant of helophytes and hydrophytes. Our results indicate that environmental factors explained the most variation in both species richness and species composition of helophytes and hydrophytes. Nevertheless, dispersal-related variables (i.e. spatial and dispersal) were also influential but less important than environmental factors. Furthermore, the dispersal-related variables were more important for hydrophytes than for helophytes. Most brackish permanent lakes were mostly located in the steppe biomes of southern Transbaikalia. This characteristic along with the oldest age, the largest distances to both river and settlements and the lowest temperatures in the study region distinguished them from freshwater, drained and more nutrient-rich floodplain lakes.

Functional homogenisation occurs across many areas and organism groups, thereby seriously affecting biodiversity loss and ecosystem functioning. In this study, we examined how functional features of aquatic macrophytes have changed during a 70-year period at community and species levels in a boreal lake district. At the community level, we examined if aquatic macrophyte communities showed different spatial patterns in functional composition and functional richness in relation to main environmental drivers between the time periods. We also observed each species in functional space to assess if species with certain sets of traits have become more common or rare in the 70-year study period. We found changes in the relationship between functional community composition and the environment. The aquatic macrophyte communities showed different patterns in functional composition between the two time periods, and the main environmental drivers for these changes were partly different. Temporal changes in functional richness were only partially linked to concomitant changes in the environment, while stable factors were more important. Species’ functional traits were not associated with commonness or rarity patterns. Our findings revealed that functional homogenisation has not occurred across these boreal lakes, ranging from small oligotrophic forest lakes to larger lakes affected by human impacts.

It has been predicted that spatial beta diversity shows a decreasing trend in the Anthropocene due to increasing human impact, causing biotic homogenisation. We aimed to discover if vascular aquatic macrophyte communities show different spatial patterns in beta diversity in relation to land use and environmental characteristics in different decades from 1940s to 2010s. We aimed to discover if spatial structures differ between species‐, phylogeny‐ and functional‐based beta diversity. We used presence–absence data of aquatic macrophytes from five decades from small boreal lakes. We utilized generalised dissimilarity modelling to analyse spatial patterns in beta diversity in relation to environmental gradients. We found that lake elevation and pH were the most important variables in each decade, while land use was not particularly important in shaping beta diversity patterns. We did not find signs of a decreasing trend in spatial beta diversity in our study area during the past 70 yr. We did not find signs of either biotic homogenisation or biotic differentiation (taxonomic, phylogenetic or functional). Vascular aquatic macrophyte communities showed only slightly different beta diversity patterns in relation to human impact across decades. The patterns of different facets of beta diversity diverged only slightly from each other. Lake position in the landscape, reflecting both natural connectivity and lake characteristics, explained the patterns found in beta diversity, probably because our study area has faced only modest changes in land use from 1940s to 2010s when compared globally. Our study highlights the fact that biotic homogenisation is not an unambiguous process acting similarly at all spatial and temporal scales or in different environments and different organism groups.

Unlike in land plants, photosynthesis in many aquatic plants relies on bicarbonate in addition to carbon dioxide (CO2) to compensate for the low diffusivity and potential depletion of CO2 in water. Concentrations of bicarbonate and CO2 vary greatly with catchment geology. In this study, we investigate whether there is a link between these concentrations and the frequency of freshwater plants possessing the bicarbonate use trait. We show, globally, that the frequency of plant species with this trait increases with bicarbonate concentration. Regionally, however, the frequency of bicarbonate use is reduced at sites where the CO2 concentration is substantially above the air equilibrium, consistent with this trait being an adaptation to carbon limitation. Future anthropogenic changes of bicarbonate and CO2 concentrations may alter the species compositions of freshwater plant communities.

Ecosystem services are fundamental to the well-being and health of people. Despite the growing awareness of the positive impacts of ecosystem services on human health, researchers have often ignored many ecosystem functions that are disadvantageous to humans. These negative facets of ecosystems are called ecosystem disservices. The central focus of this study was to test the applicability of Geographic Information Systems-based spatial accessibility analysis in mapping the potential risk of ecosystem disservice at a national scale. We used tick exposure as an example of a disservice. Worldwide, ticks (genus Ixodes) are the primary vectors of several dangerous diseases which pose threats to people. As the probability of encountering infectious ticks has increased during the last decades, new spatial information on high-risk tick exposure areas are needed. To evaluate exposure risk, we developed a tick probability map based on tick observations and environmental variables in Finland. First, we analyzed what kind of threat ticks pose to populations in residential areas and around free-time residences. Second, we studied if the movement of people (here school children) in the everyday environment increased tick exposure risk. We calculated the shortest school route for all children by using spatial accessibility analysis. Our results showed that taking the movement of people into consideration through the accessibility analysis, we can get a more realistic picture of tick exposure risk. Further, we gained a better overview of the number of children at higher exposure risk. This kind of information is crucial for pre-assessment and identification of public health strategies for control and minimizing tick-borne diseases. In general, the accessibility approach provided a good overview of areas where the greatest tick exposure was present and produced valuable information to support decision-making. The method enabled new insights into the assessment of exposure t

Metacommunity ecology has broadened considerably with the recognition that measuring beta diversity beyond the purely taxonomic viewpoint may improve our understanding of the dispersal- and niche-based mechanisms across biological communities. In that perspective, we applied a novel multidimensional approach including taxonomic, functional and phylogenetic data to enhance our basic understanding of macrophyte metacommunity dynamics. For each beta diversity metric, we calculated the mean overall value and tested whether the mean value was different from that expected by chance using null models. We also employed evolutionary and spatially constrained models to first identify the degree to which the studied functional traits showed a phylogenetic signal, and then to estimate the relative importance of spatial and environmental effects on metacommunity structure. We first found that most individual ponds were inhabited by species that were merely random draws from the taxonomic and phylogenetic species pool available in the study region. Contrary to our expectations, not all measured traits were conserved along the phylogeny. We also showed that trait and phylogenetic dimensions strongly increased the amount of variation in beta diversity that can be explained by degree of environmental filtering and dispersal limitation. This suggests that accounting for functional traits and phylogeny in metacommunity ecology helps to explain idiosyncratic patterns of variation in macrophyte species distribution. Importantly, phylogenetic and functional analyses identified the influence of underlying mechanisms that would otherwise be missed in an analysis of taxonomic turnover. Together, these results let us conclude that macrophyte species have labile functional traits adapted to dispersal-based processes and some evolutionary trade-offs that drive community assembly via species sorting. Overall, our exploration of different facets of beta diversity showed how functional a

Human welfare is dependent on the availability of ecosystem services (ESs). There is an urgent need to explore the balance between ES production and consumption areas to ensure the sustainable use of the natural capital. Here, we present a spatial accessibility analysis to explicitly evaluate the balance between ES supply and demand across Europe. We used a central food product (crop) as an example of provisioning ES, where transportation is required to satisfy the demand. Our results show large differences in a country’s ability to produce food in relation to its demand, leading to significant risks of over- and underproduction on a regional scale. An ecosystem’s capacity to provide services exceeded especially in the middle of Europe. The majority of the countries would benefit significantly by balancing the supply and demand at international level, even at close distances. Our results demonstrate how the situation in Europe can change if the international distribution of the food ES is prevented. By using a state-of-the-art accessibility method instead of commonly used overlay analysis, it is possible to identify where to invest in transportation and enhance natural capacity to respond to the possible changes in food production or the growing demand of food energy.

The natural diversity of Earth consists of two main elements: the diversity of biotic nature (biodiversity) and the diversity of abiotic nature (geodiversity). Their relationship is theoretically strong but insufficiently studied. A conservation principle called Conserving Nature’s Stage (CNS) states that geodiversity (e.g. data on geological, geomorphological and hydrological richness) could be used as a coarse filter strategy for conserving biodiversity in changing environmental conditions. It is based on an idea that areas where geodiversity is high are capable of supporting high biodiversity, because organisms depend on the abiotic “stage” on which they exist. The capability of present conservation actions to protect and sustain biodiversity in the face of global change is under debate, and CNS is proposed as one complementary solution to this issue. There is an urgent need for studies that examine the relationship between geo— and biodiversity to assess the possibilities of CNS for nature conservation. In this thesis, I explored the potentiality of how geodiversity information can be used in assessing biodiversity by examining their relationship in different areas, at different spatial scales and with different measures. This thesis consists of three studies: (1) a study where the importance of geodiversity, topographical and climatic variables to threatened species diversity and rarity was analysed, (2) a study where geodiversity and vascular plant species richness were examined at different land-use intensity (hemeroby) levels, and (3) a study where landforms were evaluated based on their vascular plant diversity. My most important goal was to determine how landforms and landscape-scale geodiversity (i.e. variables for which the geological, geomorphological and hydrological feature richness are accounted) are related to biodiversity (i.e. the species diversity and rarity of vascular plants and other taxa). The results highlighted the overall positive

Unlike in land plants, photosynthesis in many aquatic plants relies on bicarbonate in addition to carbon dioxide (CO₂) to compensate for the low diffusivity and potential depletion of CO₂ in water. Concentrations of bicarbonate and CO₂ vary greatly with catchment geology. In this study, we investigate whether there is a link between these concentrations and the frequency of freshwater plants possessing the bicarbonate use trait. We show, globally, that the frequency of plant species with this trait increases with bicarbonate concentration. Regionally, however, the frequency of bicarbonate use is reduced at sites where the CO₂ concentration is substantially above the air equilibrium, consistent with this trait being an adaptation to carbon limitation. Future anthropogenic changes of bicarbonate and CO₂ concentrations may alter the species compositions of freshwater plant communities.

Aim: Conserving freshwater biodiversity in a rapidly changing world requires updated planning schemes and research efforts. Geodiversity — the diversity of Earth surface forms, materials and processes — and biodiversity are interlinked at a fundamental level. This relationship is being considered in a growing number of studies, yet research from freshwater environments is scarce. We used geodiversity (rock‐type, soil‐type and geomorphological richness), local and climatic variables to explore whether geodiversity can be used as a surrogate for aquatic plant species richness in lakes and rivers. Location: Finland. Taxon: Aquatic plants. Methods: We compared geodiversity variables (measured within 1‐km² grid cells) to well‐studied local (e.g. area, alkalinity) and climate (e.g. growing degree‐days) variables, and examined the patterns between habitat types (lakes and rivers) and among all taxa and major functional groups (helophytes and hydrophytes). We modelled lake (n = 145) and river (n = 146) plant species richness with generalized linear models, and further partitioned variation to measure the independent and shared contributions of the geodiversity, climate and local environmental variable groups. As a complementary analysis, and to identify single important variables explaining variation in aquatic plant species richness, we utilized boosted regression trees. Results: We found a positive relationship between aquatic plant species richness and catchment geodiversity variation with recurring patterns across two different freshwater habitat types and two aquatic plant functional groups. Higher variation in geodiversity (measured at landscape scale) supported higher freshwater biodiversity (measured at the local scale) of lakes and rivers. Main conclusions: Geodiversity can be a useful addition to biodiversity modelling, and it should be considered in conservation schemes and monitoring efforts, further supporting the principle of conserving nature’s stage

Aim: Geodiversity underpins biodiversity, but the contribution of specific geofeatures or landforms has rarely been explored. In this study, we use multiple vascular plant species diversity measures on alpha, beta and gamma levels to explore the linkage between biodiversity and co‐located landforms (e.g. gullies, dunes and lake shores). We hypothesize that biodiversity will be positively related to geodiversity, which is founded on distinct landforms. Additionally, we propose that different landforms will sustain different amounts of biodiversity and that high alpha and gamma diversity values are related to landform‐driven moisture availability whereas high beta diversity relates especially to landform‐specific microtopographic variation. Location: Rokua UNESCO Global Geopark area, Finland. Taxon: Vascular plants. Methods: We compare vascular plant species richness measures, Shannon’s and Simpson’s diversity indices, rarity‐weighted richness and local contribution to beta diversity at altogether three levels of biodiversity (alpha, beta and gamma) for different landforms. Landform information is compiled from aerial photos, spatial data layers and targeted field surveys. We compare results to control habitat (i.e. sites without any distinct landforms) within the study area. Results: Vascular plant diversity was higher on landforms than in control habitat. There was also notable variation between species diversity of different landforms. Moisture‐rich gullies and river shores were especially diverse at all three levels, whereas aapa mires hosted most unique species composition (highest beta diversity). Beta diversity patterns were rather comparable with alpha and gamma diversity patterns, which contradict our hypothesis. Main conclusions: This study quantitatively established a strong connection between terrestrial plant communities and multiple landforms. Our results highlighted the landform‐controlled variation in soil moisture, microclimate and microtopog

Species distributions are structured by regional and local determinants, which operate at multiple spatial and temporal scales. The purpose of our work was to distinguish the relative roles of local variables, climate, geographical location and post glaciation condition (i.e., delineation between supra- and subaquatic lakes during the post-glacial Ancylus Lake) in explaining variation in macrophyte community composition of all taxa, helophytes and hydrophytes. In addition, we investigated how these four explanatory variable groups affected macrophyte strategy groups based on Grime’s classification. Using partial linear regression and variation partitioning, we found that macrophyte communities are primarily filtered by local determinants together with regional characteristics at the studied spatial scale. We further evidenced that post glaciation condition indirectly influenced on local water quality variables, which in turn directly contributed to the macrophyte communities. We thus suggest that regional determinants interact with local-scale abiotic factors in explaining macrophyte community patterns and examining only regional or local factors is not sufficient for understanding how aquatic macrophyte communities are structured locally and regionally.

Species richness and spatial variation in community composition (i.e., beta diversity) are key measures of biodiversity. They are largely determined by natural factors, but also increasingly affected by anthropogenic factors. Thus, there is a need for a clear understanding of the human impact on species richness and beta diversity, the underlying mechanisms, and whether human-induced changes can override natural patterns. Here, we dissect the patterns of species richness, community composition and beta diversity in relation to different environmental factors as well as human impact in one framework: aquatic macrophytes in 66 boreal lakes in Eastern Finland. The lakes had been classified as having high, good or moderate status (according to ecological classification of surface waters in Finland) reflecting multifaceted human impact. We used generalized least square models to study the association between different environmental variables (Secchi depth, irregularity of the shoreline, total phosphorus, pH, alkalinity, conductivity) and species richness. We tested the null hypothesis that the observed community composition can be explained by random distribution of species. We used multivariate distance matrix regression to test the effect of each environmental variable on community composition, and distance-based test for homogeneity of multivariate dispersion to test whether lakes classified as high, good or moderate status have different beta diversity. We showed that environmental drivers of species richness and community composition were largely similar, although dependent on the particular life-form group studied. The most important ones were characteristics of water quality (pH, alkalinity, conductivity) and irregularity of the shoreline. Differences in community composition were related to environmental variables independently of species richness. Species richness was higher in lakes with higher levels of human impact. Lakes with different levels of hum