1. |
- Bergsten, Arvid, et al.
(author)
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Protected areas in a landscape dominated by logging - A connectivity analysis that integrates varying protection levels with competition-colonization tradeoffs
- 2013
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In: Biological Conservation. - : Elsevier BV. - 0006-3207 .- 1873-2917. ; 160, s. 279-288
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Journal article (peer-reviewed)abstract
- Conservation planning is challenging in landscapes where reoccurring habitat destruction and subsequent recovery affect metapopulation persistence, because different species respond differently to landscape change. By building on a graph-theoretical modeling framework, we here develop a connectivity model of how varying levels of area protection and unprotected areas predetermined for destruction affect species differently depending on (1) their tradeoff in colonization versus habitat utilization ability and (2) their maximum dispersal ability. We apply our model to 20,000 patches of old pine forest in northern Sweden, which host many threatened species but are scattered in a landscape dominated by intensive forestry. Unprotected mature forests stands predestined for logging are treated as adequate but temporarily available habitat for colonization specialists, whereas the same stands are assumed to, at best, serve only as intermediate stepping-stones for habitat specialists as they disperse between long-standing forests in protected areas. Our results show that the effect of habitat fragmentation on metapopulation persistence differs greatly not only depending on the dispersal distance of a particular species, but also on how well it utilizes habitat patches of different longevity. Such traits are discussed with respect to the spatiotemporal planning of habitat protection. Also, we suggest that the negative impacts of logging on biodiversity may be reduced if forestry practice is adjusted to better account for the ecological values of maturing production stands, through spatially explicit modeling of connectivity and of complementarity in the protection gradient.
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2. |
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3. |
- Birk, Sebastian, et al.
(author)
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The potential of remote sensing in ecological status assessment of coloured lakes using aquatic plants
- 2014
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In: Ecological Indicators. - : Elsevier BV. - 1470-160X .- 1872-7034. ; 46, s. 398-406
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Journal article (peer-reviewed)abstract
- Field-based survey methods for aquatic vegetation have been identified as resource-demanding. Recent advances in remote sensing (RS) with sub-decimetre resolution allow for surveying aquatic vegetation at the species level. Coloured lakes, mainly due to high concentrations of humic substances, are globally widespread. However, high colour impedes the identification of submerged vegetation via remote sensing. Here, we evaluate the potential of using only emergent, floating and floating-leaved taxa that are detectable by high-resolution RS (RS-taxa) to assess the ecological status of lakes. In a dataset covering 72 Swedish low alkaline coloured lakes, we identified 31 RS-taxa. The power of RS-taxa assemblages to predict non-RS assemblages was analysed by a combination of ordination (Detrended Correspondence Analysis, DCA, and Redundancy Analysis) and multiple regression analysis. We compared the performance of a trophic metric score based on RS-taxa with that based on field data from all taxa along different environmental gradients. Forty percent of the variability of the first non-RS taxa DCA-axis was predicted by the DCA-results based on RS-taxa. Correlations of the trophic metric score and total nitrogen concentrations were equally strong for the dataset based on RS-taxa compared to the dataset based on all taxa. For total phosphorous concentrations, the correlation was stronger for the dataset based on all taxa, but for a complex water quality gradient (including sulphate, N-species, chlorophyll and percent cover of wetlands in the riparian buffer) the correlation was higher for the RS-taxa dataset. The significant linkage between the two community fractions (remotely-sensible and non-sensible) revealed considerable assemblage concordance, suggesting a notable potential of the use of remote sensing in lake macrophyte monitoring. The established trophic metric score seems most qualified for surveillance monitoring that, in combination with the eased efforts of data acquisition, detects long-term changes of the aquatic environment caused by shifts in climate, land use and (related) eutrophication. (C) 2014 Elsevier Ltd. All rights reserved.
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4. |
- Brila, Ilze, et al.
(author)
-
Low-level environmental metal pollution is associated with altered gut microbiota of a wild rodent, the bank vole (Myodes glareolus)
- 2021
-
In: Science of the Total Environment. - : Elsevier. - 0048-9697 .- 1879-1026. ; 790
-
Journal article (peer-reviewed)abstract
- Mining and related industries are a major source of metal pollution. In contrast to the well-studied effects of exposure to metals on animal physiology and health, the impacts of environmental metal pollution on the gut microbiota of wild animals are virtually unknown. As the gut microbiota is a key component of host health, it is important to understand whether metal pollution can alter wild animal gut microbiota composition. Using a combination of 16S rRNA amplicon sequencing and quantification of metal levels in kidneys, we assessed whether multi-metal exposure (the sum of normalized levels of fifteen metals) was associated with changes in gut microbiota of wild bank voles (Myodes glareolus) from two locations in Finland. Exposure to increased metal load was associated with higher gut microbiota species diversity (α-diversity) and altered community composition (β-diversity), but not dispersion. Multi-metal exposure and increased levels of several metals (Cd, Hg, Pb and Se) were associated with differences in the abundance of microbial taxa, especially those within the families Clostridiales vadinBB60 group, Desulfovibrionaceae, Lachnospiraceae, Muribaculaceae and Ruminococcaceae. Our data indicate that even low-level metal pollution can affect the diversity of microbiota and be associated with deterministic differences in composition of host gut microbiota in wild animal populations. These findings highlight the need to study a broader range of metals and their cocktails that are more representative of the types of environmental exposure experienced by wild animals.
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5. |
- Cayol, Claire, et al.
(author)
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Urban forest soils harbour distinct and more diverse communities of bacteria and fungi compared to less disturbed forest soils
- 2023
-
In: Molecular Ecology. - : Wiley. - 0962-1083 .- 1365-294X. ; 32, s. 504-517
-
Journal article (peer-reviewed)abstract
- Anthropogenic changes to land use drive concomitant changes in biodiversity, including that of the soil microbiota. However, it is not clear how increasing intensity of human disturbance is reflected in the soil microbial communities. To address this issue, we used amplicon sequencing to quantify the microbiota (bacteria and fungi) in the soil of forests (n = 312) experiencing four different land uses, national parks (set aside for nature conservation), managed (for forestry purposes), suburban (on the border of an urban area) and urban (fully within a town or city), which broadly represent a gradient of anthropogenic disturbance. Alpha diversity of bacteria and fungi increased with increasing levels of anthropogenic disturbance, and was thus highest in urban forest soils and lowest in the national parks. The forest soil microbial communities were structured according to the level of anthropogenic disturbance, with a clear urban signature evident in both bacteria and fungi. Despite notable differences in community composition, there was little change in the predicted functional traits of urban bacteria. By contrast, urban soils exhibited a marked loss of ectomycorrhizal fungi. Soil pH was positively correlated with the level of disturbance, and thus was the strongest predictor of variation in alpha and beta diversity of forest soil communities, indicating a role of soil alkalinity in structuring urban soil microbial communities. Hence, our study shows how the properties of urban forest soils promote an increase in microbial diversity and a change in forest soil microbiota composition.
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6. |
- Chlot, Sara, et al.
(author)
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Effects on nutrient regime in two recipients of nitrogen-rich mine effluents in northern Sweden
- 2013
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In: Applied Geochemistry. - : Elsevier BV. - 0883-2927 .- 1872-9134. ; 31, s. 12-24
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Journal article (peer-reviewed)abstract
- The question of the limiting nutrient(s) for production of phytoplankton and macrophytes was explored in two contrasting freshwater systems receiving N- and P-rich mine effluents from the Boliden and Kiruna mine sites, northern Sweden. For both sites, total N (TN), total P (TP) and TN:TP mass ratios in water, sediment and macrophytes were used to examine (1) spatial variations within the systems, (2) differences between the systems and (3) seasonal variations. The TN concentration from the discharge point at the Kiruna site was about seven times higher than at the Boliden discharge point, while the TP concentration was 10 times lower than in the discharge point at the Boliden site. The majority of the studied lakes showed elevated biomass of phytoplankton, with maximum values found in Lake Bruträsket (Boliden). Mining activities have affected the nutrient regime of the two recipients by contributing to elevated TN and TP concentrations and TN:TP mass ratios as well as elevated production of phytoplankton and macrophytes compared to the reference sites. Depending on the NH4 concentration in the effluent at the Boliden site, water column TN:TP mass ratios shifted from being >22, indicating P-deficiency, to between 9 and 22, indicating a transition from N- to P-deficiency (co-limitation). However, water column TN:TP mass ratios at the Kiruna site always indicated P-deficiency, while TN:TP mass ratios of macrophytes indicate that both sites may vary from N- to P-limitation. The study suggests that for the design of efficient monitoring programmes and remediation measures, it is important to consider the major N and P species in water, phytoplankton, sediment and macrophytes.
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7. |
- Chlot, Sara, et al.
(author)
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Modelling nitrogen transformations in waters receiving mine effluents
- 2011
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In: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 409:21, s. 4585-4595
-
Journal article (peer-reviewed)abstract
- This paper presents a biogeochemical model developed for a clarification pond receiving ammonium nitrogen rich discharge water from the Boliden concentration plant located in northern Sweden. Present knowledge about nitrogen (N) transformations in lakes is compiled in a dynamic model that calculates concentrations of the six N species (state variables) ammonium-N (Nam), nitrate-N (Nox), dissolved organic N in water (Norg), N in phytoplankton (Npp), in macrophytes (Nmp) and in sediment (Nsed). It also simulates the rate of 16 N transformation processes occurring in the water column and sediment as well as water–sediment and water–atmosphere interactions. The model was programmed in the software Powersim using 2008 data, whilst validation was performed using data from 2006 to 2007. The sensitivity analysis showed that the state variables are most sensitive to changes in the coefficients related to the temperature dependence of the transformation processes. A six-year simulation of Nam showed stable behaviour over time. The calibrated model rendered coefficients of determination (R2) of 0.93, 0.79 and 0.86 for Nam, Nox and Norg, respectively. Performance measures quantitatively expressing the deviation between modelled and measured data resulted in values close to zero, indicating a stable model structure. The simulated denitrification rate was on average five times higher than the ammonia volatilisation rate and about three times higher than the permanent burial of Nsed and, hence, the most important process for the permanent removal of N. The model can be used to simulate possible measures to reduce the nitrogen load and, after some modification and recalibration, it can be applied at other mine sites affected by N rich effluents.
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8. |
- Choudhury, Maidul, et al.
(author)
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Disentangling the roles of plant functional diversity and plaint traits in regulating plant nitrogen accumulation and denitrification in freshwaters
- 2022
-
In: Functional Ecology. - : Wiley. - 0269-8463 .- 1365-2435. ; 36, s. 921-932
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Journal article (peer-reviewed)abstract
- 1. There is a growing recognition that functional measures of diversity, based on quantification of functionally important species traits, are useful for explaining variation in ecosystem processes. However, the mechanisms linking functional diversity to different processes remain poorly understood, hindering development of a predictive framework for ecosystem functioning based on species traits.2. The current understanding of how the functional traits of aquatic plants (macrophytes) affect nitrogen (N) cycling by regulating microbial communities and their activity in freshwater habitats is particularly limited. Denitrifying bacteria are typically associated with the roots of both aquatic and terrestrial plants and denitrification is the main cause of loss of N from ecosystems. Disentangling the interplay between plants and microbial denitrifiers is key to understanding variation in rates of denitrification from local to landscape scales.3. In a mesocosm experiment, we varied the species richness (monocultures or two-species mixtures) and composition of macrophytes. We quantified effects of both macrophyte functional diversity, quantified as functional trait dissimilarity, and functional trait composition, quantified as community weighted mean trait values, on N removal in wetlands. We used structural equation modelling to disentangle the direct and indirect influences of traits on N accumulation in plant biomass, denitrification activity and abundance of key bacterial denitrification genes (nirS and nirK).4. Both functional diversity and functional trait composition regulated N removal, explaining 70%-94% variation in the underlying ecosystem processes. Increased macrophyte functional diversity increased plant N accumulation, and indirectly enhanced denitrification by increasing denitrification gene abundance. Among traits, greater plant relative growth rates, specific leaf area and above-ground biomass increased plant N accumulation. Denitrification activity increased with increasing below-ground biomass but decreased with increasing root diameter.5. These findings improve our understanding of N removal in freshwater wetlands dominated by macrophytes, and have broad ecological implications for wetland management targeting enhanced ecosystem services. Our results highlight the potential for optimizing denitrification and plant N accumulation in wetlands and thereby improving water purification by increasing macrophyte functional diversity and ensuring the presence of key traits in macrophyte assemblages.
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9. |
- Choudhury, Maidul, et al.
(author)
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Importance of plant species for nitrogen removal using constructed floating wetlands in a cold climate
- 2019
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In: Ecological Engineering. - : Elsevier BV. - 0925-8574 .- 1872-6992. ; 138, s. 126-132
-
Journal article (peer-reviewed)abstract
- Constructed floating wetlands (CFWs) have been tested in different climatic regions and aquatic habitat types for nitrogen (N) removal from surface water, but there is limited knowledge about their applicability for N removal in cold climate regions. Most CFWs studies are conducted at the micro- or mesocosm scale, while the application of CFWs at in situ is rare. Moreover, most CFWs studies have focused on plant N accumulation without considering macrophyte root-associated denitrification as a possible N removal pathway. Here, we study the N removal potential of CFWs through N accumulation by macrophytes and potential denitrification activity (PDA) associated with plants. At a mining area in the sub-arctic region of Sweden receiving N-rich mine effluents, we tested the concept of CFWs and evaluated the performance of six native, emerging macrophyte species planted in CFWs. The CFWs were deployed in two types of systems: in situ in the recipient lake, subjected to ambient N concentrations, and CFWs placed in water-side "eco-tanks", subjected to higher N concentrations. We showed that macrophyte establishment in CFWs is feasible under cold climatic conditions, both in situ and eco-tanks. The standing biomass of macrophytes, bulk N accumulation in plant biomass and PDA in mesocosms were 0.54-2.25 kg m(-2), 7.56-24.75 mg N m(-2) d(-1) and 31.82-2250.77 mg N2O-N m(-2) d(-1), respectively. In the recipient, the variation was larger and the values were higher (standing biomass, 0.37-6.74 kg m(-2); bulk N accumulation, 8.09-106.93 mg N m(-2) d(-1); PDA, 11.89-8446.15 mg N m(-2) d(-1)). Macrophyte root-associated denitrification was the main N removal pathway in the CFWs. Given the demonstrated applicability of CFWs and the high denitrification rates that can be obtained, future studies should focus on designing CFWs to enhance denitrification as this process leads to permanent removal of N from the water phase.
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10. |
- Choudhury, Maidul, et al.
(author)
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Mixtures of macrophyte growth forms promote nitrogen cycling in wetlands
- 2018
-
In: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 635, s. 1436-1443
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Journal article (peer-reviewed)abstract
- The importance of aquatic plant diversity in regulating nutrient cycling in wetlands remains poorly understood. We investigated how variation in macrophyte growth form (emerging, submerged and bryophyte) combinations and species mixtures affect nitrogen (N) removal from the water and N accumulation in plant biomass. We conducted a wetland mesocosm experiment for 100 days during July-September 2015. Twelve species were grown in mono- and in two-species mixed cultures for a total of 32 single and two-growth form combinations. Nitrogen removal from the water was quantified on three occasions during the experiment, while N accumulation in plant biomass was determined following termination of the experiment. The number of species and growth forms present increased N removal and accumulation. The growth form combinations of emerging and bryophyte species showed the highest N accumulation and N removal from water, followed by combinations of emerging species. By contrast, submerged species growing in the presence of emerging or other submerged species showed the lowest levels of N accumulation and N removal. Temporal variation in N removal also differed among growth form combinations: N removal was highest for emerging-bryophyte combinations in July, but peaked for the emerging-submerged and emerging-bryophyte combinations in August. Indeed, the occurrence of complementarity among macrophyte species, particularly in combinations of bryophyte and emerging species, enhanced N removal and uptake during the entire growing season. Our study highlights the importance of bryophytes, which have been neglected in research on nutrient cycling in wetlands, for aquatic N cycling, especially given their worldwide distribution across biomes. Overall, our findings point towards the potential important role of the diversity of macrophyte growth forms in regulating key ecosystem processes related to N cycling in wetlands. (C) 2018 Elsevier B.V. All rights reserved.
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11. |
- Christensen, Pernilla, et al.
(author)
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Can landscape properties predict occurrence of grey-sided voles?
- 2008
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In: Population Ecology. - : Wiley. - 1438-3896 .- 1438-390X. ; 50:2, s. 169-179
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Journal article (peer-reviewed)abstract
- There has been a long-term decline in spring and fall numbers of Clethrionomys rufocanus in boreal Sweden in 1971-2005. Previous studies on permanent sampling plots in the centre of 2.5 x 2.5 km landscapes suggested that habitat fragmentation (sensu destruction) could have contributed to the decline. Therefore, we tested these findings in a field study and compared trapping results on the central sampling plots of landscapes with a low degree of fragmentation (LDF) and of "hot spot" type with trapping results in managed forest landscapes with a high degree of fragmentation (HDF). We predicted that C. rufocanus would be more common on the LDF plots. We used our permanent plots supplemented with a new sample of plots, mainly of the rare LDF type, inside or just outside the long-term study area. Very few voles were trapped on both plot types, and no difference was found. However, a subsequent pilot study with trapping in a national park with large areas of pristine, unfragmented forest yielded more voles than in the managed, more fragmented, areas. Consequently, the initial field study data and some other recent data were also re-analysed from a "local patch quality" perspective. This alternative approach revealed the positive importance of large focal patches of forest > 60 years old and their content of old-growth (pine) forest (> 100 years). Interestingly, at the landscape level, the frequency distribution of patches of forest > 60 years old, old-growth (> 100 years), and especially of old-growth pine forest (> 100 years), relative to the properties of plots with C. rufocanus, suggested that there are few forest patches left that are suitable for C. rufocanus. Our current results suggest that habitat fragmentation cannot be excluded as a contributing cause to the long-term decline of C. rufocanus in boreal Sweden.
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12. |
- Christensen, Pernilla, et al.
(author)
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Dependence of Clethrionomys rufocanus on focal forest patch size and quality
- 2006
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In: Book of Abstracts. ; , s. 19-20
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Conference paper (other academic/artistic)abstract
- The "local patch quality perspective" revealed the importance to C. rufocanus of a large patch of forest >60 yr old containing a lot of old-growth (pine) forest (>100 yr). In fact, at the landscape level, the frequency distribution of focal patches of forest >60 yr old and especially their content of old-growth pine forest (>100 yr), relative to the properties of plots with C. rufocanus, suggests that there are few forest patches left that are suitable for C. rufocanus in our study area. Our results strongly suggest habitat fragmentation as a contributing cause to the long-term decline of C. rufocanus.
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13. |
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14. |
- Christensen, Pernilla, et al.
(author)
-
Fåglar i ett landskapsperspektiv – ett samarbete mellan Nationell Inventering av Landskapet i Sverige (NILS) och Svensk Fågeltaxering (SFT)
- 2011
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Reports (other academic/artistic)abstract
- Syftet med denna studie var tvådelat där den första delen var att ta fram en effektiv flygbildsinventeringsmetodik för att kunna inventera ett större landskapsutsnitt än 1 x 1 km rutan och den andra delen var att hitta ett samband mellan myrfåglar och de landskapsdata som vi kunde plocka fram med den nya metodiken. Den flygbildsinventeringsmetodik som tagits fram under detta projekt medför att ett större område (3 x 3 km) kan inventeras på relativt kort tid (i genomsnitt 2 dagar). Tidsåtgången för att inventera hela 5 x 5 km rutan med denna metodik uppskattas till ca 3 dagar. Skillnaden från ordinarie NILS metodik är att betydligt större strukturer fångas upp eftersom karteringsenheten är större men även att detaljrikedomen som finns inom ordinarie NILS har fått minska betydligt. Med tiden finns förhoppningen att kunna effektivisera denna typ av flygbildsinventering än mer då den flygbildsinventeringstid som lagts ned under detta projekt även räknar in utveckling av metoden. I väntan på att nya möjligheter skall utvecklas skulle den metodik som vi tagit fram kunna utgöra en bra stomme för fortsatt verksamhet på en större skala än 1 x 1 km. Våra analyser av fågelarter på myrar och landskapsdata visade att fågeldata utgjorde för lite data för att vi skulle kunna se tydliga mönster samt kunna gå ned på den detaljnivå dvs. finindelning av myren, som vi ville. Tanken med den framtagna flygbildsinventeringsmetodiken var att ge data som passade för fler organismgrupper än fåglar samt att dessa data skulle kunna nyttjas även inom andra projekt såsom lillNILS. På grund av att projektet försökte svara mot både ett specifikt behov (SFT:s) samt ett mer generellt så kan vi konstatera att valet av rutor inte blev helt optimalt för att matcha landskapsdata från myrar med fågeldata. Vid fortsatta analyser kan det vara lämpligt att göra ett urval av de rutor som ligger i områden där dessa arter har sitt häckningsområde för att på så sätt begränsa antalet rutor med noll förekomst av dessa arter. Dessutom är det önskvärt att analysera flera NILS-rutor med en totalarea av myrar mellan 150 och 220 ha.
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15. |
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16. |
- Dudley, Bernard J., et al.
(author)
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Measurements of uncertainty in macrophyte metrics used to assess European lake water quality
- 2013
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In: Hydrobiologia. - : Springer Science and Business Media LLC. - 0018-8158 .- 1573-5117. ; 704:1, s. 179-191
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Journal article (peer-reviewed)abstract
- Uncertainty is an important factor in ecological assessment, and has important implications for the ecological classification and management of lakes. However, our knowledge of the effects of uncertainty in the assessment of different ecological indicators is limited. Here, we used data from a standardized campaign of aquatic plant surveys, in 28 lakes from 10 European countries, to assess variation in macrophyte metrics across a set of nested spatial scales: countries, lakes, sampling stations, replicate transects, and replicate samples at two depth-zones. Metrics investigated in each transect included taxa richness, maximum depth of colonisation and two indicators of trophic status: Ellenberg’s N and a metric based on phosphorus trophic status. Metrics were found to have a slightly stronger relationship to pressures when they were calculated on abundance data compared to presence/absence data. Eutrophication metrics based on helophytes were found not to be useful in assessing the effects of nutrient pressure. These metrics were also found to vary with the depth of sampling, with shallower taxa representing higher trophic status. This study demonstrates the complex spatial variability in macrophyte communities, the effect of this variability on the metrics, and theimplications to water managers, especially in relation to survey design.
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17. |
- Ecke, Frauke
(author)
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A comparative analysis reveals little evidence for niche conservatism in aquatic macrophytes among four areas on two continents
- 2017
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In: Oikos. - : Wiley. - 0030-1299 .- 1600-0706. ; 126, s. 136-148
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Journal article (peer-reviewed)abstract
- One of the most intriguing questions in current ecology is the extent to which the ecological niches of species are conserved in space and time. Niche conservatism has mostly been studied using coarse-scale data of species' distributions, although it is at the local habitat scales where species' responses to ecological variables primarily take place. We investigated the extent to which niches of aquatic macrophytes are conserved among four study regions (i.e. Finland, Sweden and the US states of Minnesota and Wisconsin) on two continents (i.e. Europe and North America) using data for 11 species common to all the four study areas. We studied how ecological variables (i.e. local, climate and spatial variables) explain variation in the distributions of these common species in the four areas using species distribution modelling. In addition, we examined whether species' niche parameters vary among the study regions. Our results revealed large variation in both species' responses to the studied ecological variables and in species' niche parameters among the areas. We found little evidence for niche conservatism in aquatic macrophytes, though local environmental conditions among the studied areas were largely similar. This suggests that niche shifts, rather than different environmental conditions, were responsible for variable responses of aquatic macrophytes to local ecological variables. Local habitat niches of aquatic macrophytes are mainly driven by variations in local environmental conditions, whereas their climate niches are more or less conserved among regions. This highlights the need to study niche conservatism using local-scale data to better understand whether species' niches are conserved, because different niches (e.g. local versus climate) operating at various scales may show different degrees of conservatism. The extent to which species' niches are truly conserved has wide practical implications, including for instance, predicting changes in species' distributions in response to global change.
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18. |
- Ecke, Frauke, et al.
(author)
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Anaplasma phagocytophilum evolves in geographical and biotic niches of vertebrates and ticks
- 2019
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In: Parasites and Vectors. - : Springer Science and Business Media LLC. - 1756-3305. ; 12
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Journal article (peer-reviewed)abstract
- Background: Anaplasma phagocytophilum is currently regarded as a single species. However, molecular studies indicate that it can be subdivided into ecotypes, each with distinct but overlapping transmission cycle. Here, we evaluate the interactions between and within clusters of haplotypes of the bacterium isolated from vertebrates and ticks, using phylogenetic and network-based methods.Methods: The presence of A. phagocytophilum DNA was determined in ticks and vertebrate tissue samples. A fragment of the groEl gene was amplified and sequenced from qPCR-positive lysates. Additional groEl sequences from ticks and vertebrate reservoirs were obtained from GenBank and through literature searches, resulting in a dataset consisting of 1623 A. phagocytophilum field isolates. Phylogenetic analyses were used to infer clusters of haplotypes and to assess phylogenetic clustering of A. phagocytophilum in vertebrates or ticks. Network-based methods were used to resolve host-vector interactions and their relative importance in the segregating communities of haplotypes.Results: Phylogenetic analyses resulted in 199 haplotypes within eight network-derived clusters, which were allocated to four ecotypes. The interactions of haplotypes between ticks, vertebrates and geographical origin, were visualized and quantified from networks. A high number of haplotypes were recorded in the tick Ixodes ricinus. Communities of A. phagocytophilum recorded from Korea, Japan, Far Eastern Russia, as well as those associated with rodents had no links with the larger set of isolates associated with I. ricinus, suggesting different evolutionary pressures. Rodents appeared to have a range of haplotypes associated with either Ixodes trianguliceps or Ixodes persulcatus and Ixodes pavlovskyi. Haplotypes found in rodents in Russia had low similarities with those recorded in rodents in other regions and shaped separate communities.Conclusions: The groEl gene fragment of A. phagocytophilum provides information about spatial segregation and associations of haplotypes to particular vector-host interactions. Further research is needed to understand the circulation of this bacterium in the gap between Europe and Asia before the overview of the speciation features of this bacterium is complete. Environmental traits may also play a role in the evolution of A. phagocytophilum in ecotypes through yet unknown relationships.
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19. |
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20. |
- Ecke, Frauke
(author)
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Average niche breadths of species in lake macrophyte communities respond to ecological gradients variably in four regions on two continents
- 2017
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In: Oecologia. - : Springer Science and Business Media LLC. - 0029-8549 .- 1432-1939. ; 184, s. 219-235
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Journal article (peer-reviewed)abstract
- Different species' niche breadths in relation to ecological gradients are infrequently examined within the same study and, moreover, species niche breadths have rarely been averaged to account for variation in entire ecological communities. We investigated how average environmental niche breadths (climate, water quality and climate-water quality niches) in aquatic macrophyte communities are related to ecological gradients (latitude, longitude, altitude, species richness and lake area) among four distinct regions (Finland, Sweden and US states of Minnesota and Wisconsin) on two continents. We found that correlations between the three different measures of average niche breadths and ecological gradients varied considerably among the study regions, with average climate and average water quality niche breadth models often showing opposite trends. However, consistent patterns were also found, such as widening of average climate niche breadths and narrowing of average water quality niche breadths of aquatic macrophytes along increasing latitudinal and altitudinal gradients. This result suggests that macrophyte species are generalists in relation to temperature variations at higher latitudes and altitudes, whereas species in southern, lowland lakes are more specialised. In contrast, aquatic macrophytes growing in more southern nutrient-rich lakes were generalists in relation to water quality, while specialist species are adapted to low-productivity conditions and are found in highland lakes. Our results emphasise that species niche breadths should not be studied using only coarse-scale data of species distributions and corresponding environmental conditions, but that investigations on different kinds of niche breadths (e.g., climate vs. local niches) also require finer resolution data at broad spatial extents.
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21. |
- Ecke, Frauke
(author)
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Beavers as ecosystem engineers
- 2020
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In: Beaver as a renewable resource : A beaver dam handbook for the Baltic Sea Region. ; , s. 32-37
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Book chapter (other academic/artistic)
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22. |
- Ecke, Frauke
(author)
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Bedömningsgrunder för makrofyter i sjöar : bakgrundsrapport
- 2007
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Reports (other academic/artistic)abstract
- De befintliga bedömningsgrunderna för makrofyter (BGM) i sjöar har hittills ansetts som preliminära. Dessutom motsvarade de inte kraven enligt EUs Ramdirektiv för vatten med avseende på bl.a. typanpassningen och angivna gränser mellan olika klasser av ekologisk status. I det framlagda förslaget för revideringen av BGM i enlighet med EUs Ramdirektiv för vatten, lades stor vikt vid att utöka dataunderlaget av framför allt referenssjöar. Med hjälp av olika påverkanskriterier valdes 49 referenssjöar, dvs. sjöar som ansågs vara av hög ekologisk status. Som kriterier användes markanvändning, sjösänkning, koncentrationen av näringsämnen samt pH i vattenfasen. Baserad på artsammansättningen bland makrofyterna gjordes en klusteranalys-baserad typindelning i tre grupper. Dessa tre typologigrupper kunde skiljas åt med hjälp av främst två typologivariabler, nämligen Y-koordinat och h.ö.h. De tre typologigrupperna/regionerna var sjöar S om Limes norrlandicus (LN), sjöar N om LN men under högsta kustlinjen (HK) samt sjöar N om LN och över HK. För att bestämma sjöarnas ekologiska status, beräknades indikatorvärden längs Tot-P-gradienten för alla funna makrofytarter förutom helofyter. Indikatorvärdena viktades med arternas nischbredd längs Tot-P-gradienten. För varje sjö kunde på det viset ett medianindikatorvärde, ett trofiindex, beräknas. Dessa trofiindex översattes till en femgradig skala enligt Ramdirektivets krav, dvs. de fem klasserna av ekologisk status. Denna konvertering gjordes med hjälp av Tot-P halter som prefereras av makrofytarter som ansågs karakteristiska för respektive klass av ekologisk status. På grund av bristande dataunderlag kunde gränsvärden inte beräknas mellan klasserna otillfredsställande och dålig ekologisk status. Trots ett heterogent datamaterial som är insamlat i olika syften, under olika decennier och till och med sekler och med varierande metodik mm., anses det föreslagna systemet kunna tillämpas i enlighet med EUs Ramdirektiv för vatten. Föreliggande utredning understryker dock det stora behovet av kompletterande inventeringar samt av en revidering av undersökningsmetoden för inventering av makrofyter. Det föreslagna systemet bör verifieras med datamaterial som inte användes för den här redovisade bedömningen. Därefter bör en eventuell revidering genomföras.
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23. |
- Ecke, Frauke
(author)
-
Bedömningsgrunder för makrofyter i sjöar : bakgrundsrapport
- 2007. - 2007:17
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Reports (other academic/artistic)abstract
- De befintliga bedömningsgrunderna för makrofyter (BGM) i sjöar har hittills ansetts sompreliminära. Dessutom motsvarade de inte kraven enligt EUs Ramdirektiv för vatten medavseende på bl.a. typanpassningen och angivna gränser mellan olika klasser av ekologiskstatus.I det framlagda förslaget för revideringen av BGM i enlighet med EUs Ramdirektiv förvatten, lades stor vikt vid att utöka dataunderlaget av framför allt referenssjöar. Med hjälp avolika påverkanskriterier valdes 49 referenssjöar, dvs. sjöar som ansågs vara av hög ekologiskstatus. Som kriterier användes markanvändning, sjösänkning, koncentrationen avnäringsämnen samt pH i vattenfasen. Baserad på artsammansättningen bland makrofyternagjordes en klusteranalys-baserad typindelning i tre grupper. Dessa tre typologigrupper kundeskiljas åt med hjälp av främst två typologivariabler, nämligen Y-koordinat och h.ö.h. De tretypologigrupperna/regionerna var sjöar S om Limes Norrlandicus (LN), sjöar N om LN menunder högsta kustlinjen (HK) samt sjöar N om LN och över HK.För att bestämma sjöarnas ekologiska status, beräknades indikatorvärden längs Tot-Pgradientenför alla funna makrofytarter förutom helofyter. Indikatorvärdena viktades medarternas nischbredd längs Tot-P-gradienten. För varje sjö kunde på det viset ettmedianindikatorvärde, ett trofiskt makrofytindex (TMI), beräknas. Dessa trofiindex översattestill en femgradig skala enligt Ramdirektivets krav, dvs. de fem klasserna av ekologisk status.Denna konvertering gjordes med hjälp av Tot-P halter som prefereras av makrofytarter somansågs karakteristiska för respektive klass av ekologisk status. På grund av bristandedataunderlag kunde gränsvärden inte beräknas mellan klasserna otillfredsställande och dåligekologisk status.Trots ett heterogent datamaterial som är insamlat i olika syften, under olika decennier och tilloch med sekler och med varierande metodik mm., anses det föreslagna systemet kunnatillämpas i enlighet med EUs Ramdirektiv för vatten. Föreliggande utredning understrykerdock det stora behovet av kompletterande inventeringar samt av en revidering avundersökningsmetoden för inventering av makrofyter. Det föreslagna systemet bör verifierasmed datamaterial som inte användes för den här redovisade bedömningen. Därefter bör eneventuell revidering genomföras.
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24. |
- Ecke, Frauke
(author)
-
Bly i naturen förgiftar djuren
- 2020
-
In: Gifter & miljö : nya utmaningar och gamla synder 2020. - 9789162013066 ; , s. 39-43
-
Book chapter (pop. science, debate, etc.)
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25. |
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26. |
- Ecke, Frauke
(author)
-
Catchment properties and the photosynthetic trait composition of freshwater plant communities
- 2019
-
In: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 366, s. 878-881
-
Journal article (peer-reviewed)abstract
- 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.
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27. |
- Ecke, Frauke
(author)
-
Compositional breakpoints of freshwater plant communities across continents
- 2023
-
In: Limnetica. - : Asociacion Iberica de Limnologia. - 0213-8409. ; 42, s. 291-301
-
Conference paper (peer-reviewed)abstract
- 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-evolutiona-ry 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.
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28. |
- Ecke, Frauke
(author)
-
Contrasting the roles of section length and instream habitat enhancement for river restoration success: a field study of 20 European restoration projects
- 2015
-
In: Journal of Applied Ecology. - : Wiley. - 0021-8901 .- 1365-2664. ; 52, s. 1518-1527
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Journal article (peer-reviewed)abstract
- Restoration of river hydromorphology often has limited detected effects on river biota. One frequently discussed reason is that the restored river length is insufficient to allow populations to develop and give the room for geomorphological processes to occur. We investigated ten pairs of restored river sections of which one was a large project involving a long, intensively restored river section and one represented a smaller restoration effort. The restoration effect was quantified by comparing each restored river section to an upstream non-restored section. We sampled the following response variables: habitat composition in the river and its floodplain, three aquatic organism groups (aquatic macrophytes, benthic invertebrates and fish), two floodplain-inhabiting organism groups (floodplain vegetation, ground beetles), as well as food web composition and land-water interactions reflected by stable isotopes. For each response variable, we compared the difference in dissimilarity of the restored and nearby non-restored section between the larger and the smaller restoration projects. In a second step, we regrouped the pairs and compared restored sections with large changes in substrate composition to those with small changes. When comparing all restored to all non-restored sections, ground beetles were most strongly responding to restoration, followed by fish, floodplain vegetation, benthic invertebrates and aquatic macrophytes. Aquatic habitats and stable isotope signatures responded less strongly. When grouping the restored sections by project size, there was no difference in the response to restoration between the projects targeting long and short river sections with regard to any of the measured response variables except nitrogen isotopic composition. In contrast, when grouping the restored sections by substrate composition, the responses of fish, benthic invertebrates, aquatic macrophytes, floodplain vegetation and nitrogen isotopic composition were greater in sections with larger changes in substrate composition as compared to those with smaller changes.Synthesis and applications. The effects of hydromorphological restoration measures on aquatic and floodplain biota strongly depend on the creation of habitat for aquatic organisms, which were limited or not present prior to restoration. These positive effects on habitats are not necessarily related to the restored river length. Therefore, we recommend a focus on habitat enhancement in river restoration projects.The effects of hydromorphological restoration measures on aquatic and floodplain biota strongly depend on the creation of habitat for aquatic organisms, which were limited or not present prior to restoration. These positive effects on habitats are not necessarily related to the restored river length. Therefore, we recommend a focus on habitat enhancement in river restoration projects.
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29. |
- Ecke, Frauke, et al.
(author)
-
Dampening of population cycles in voles affects small mammal community structure, decreases diversity, and increases prevalence of a zoonotic disease
- 2017
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In: Ecology and Evolution. - : Wiley. - 2045-7758. ; 7, s. 5331-5342
-
Journal article (peer-reviewed)abstract
- Long-term decline and depression of density in cyclic small rodents is a recent widespread phenomenon. These observed changes at the population level might have cascading effects at the ecosystem level. Here, we assessed relationships between changing boreal landscapes and biodiversity changes of small mammal communities. We also inferred potential effects of observed community changes for increased transmission risk of Puumala virus (PUUV) spread, causing the zoonotic disease nephropatica epidemica in humans. Analyses were based on long-term (1971-2013) monitoring data of shrews and voles representing 58 time series in northern Sweden. We calculated richness, diversity, and evenness at alpha, beta, and gamma level, partitioned beta diversity into turnover (species replacement) and nestedness (species addition/removal), used similarity percentages (SIMPER) analysis to assess community structure, and calculated the cumulated number of PUUV-infected bank voles and average PUUV prevalence (percentage of infected bank voles) per vole cycle. Alpha, beta, and gamma richness and diversity of voles, but not shrews, showed long-term trends that varied spatially. The observed patterns were associated with an increase in community contribution of bank vole (Myodes glareolus), a decrease of gray-sided vole (M.rufocanus) and field vole (Microtus agrestis) and a hump-shaped variation in contribution of common shrew (Sorex araneus). Long-term biodiversity changes were largely related to changes in forest landscape structure. Number of PUUV-infected bank voles in spring was negatively related to beta and gamma diversity, and positively related to turnover of shrews (replaced by voles) and to community contribution of bank voles. The latter was also positively related to average PUUV prevalence in spring. We showed that long-term changes in the boreal landscape contributed to explain the decrease in biodiversity and the change in structure of small mammal communities. In addition, our results suggest decrease in small mammal diversity to have knock-on effects on dynamics of infectious diseases among small mammals with potential implications for disease transmission to humans.
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30. |
- Ecke, Frauke, et al.
(author)
-
Decline of grey-sided voles in managed boreal forests tracks long-term habitat fragmentation
- 2006
-
In: Book of Abstracts. ; , s. 24-25
-
Conference paper (other academic/artistic)abstract
- There has been a long-term decline, causing frequent local extinctions, of cyclic grey-sided voles (Clethrionomys rufocanus) in northern Fennoscandia since 1971. Previous studies supported the hypothesis that altered landscape structure, especially in terms of forest patch area and fragmentation of oldgrowth forest, has contributed to the decline. Since those studies were based on cumulated vole time series data and static landscape structure, we now tested whether the long-term decline was related to a gradual change. We digitized landcover types (>0.25 ha) from aerial photographs within 6.25 km2 squares centred on each of the 27 sampling sites with 5 year intervals, starting in 1970. Because of clear-cutting, mean area of the patches of >35 year old forest that intersected the sampling sites decreased from 126 ha in 1970 to 44 ha in 2004. The main decrease in focal forest patch area occurred in 198085, coinciding with the major drop in vole numbers. Our results strongly suggest that long-term habitat fragmentation is involved in the current decline of grey-sided voles. However, climate change leading to warmer winters with a less stable snow cover is also thought to be of major importance, as indicated by a decrease in vole wintering success.
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31. |
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32. |
- Ecke, Frauke, et al.
(author)
-
Does macrophyte-based lake status assessment according to the EU Water Framework Directive conflict with the EU Habitat Directive in Fennoscandia?
- 2009
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In: Aquatic Weeds 2009. - : Edita Publishing Oy. - 9789521134999 - 9789521135002 ; , s. 65-
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Conference paper (other academic/artistic)abstract
- Recently, many member states of the European Union (EU) have finalised and implemented national systems for water quality assessment in lakes according to the EU Water Framework Directive (WFD). It is however unknown how the assessment of ecological status, according to the WFD, relates to the status of lakes according to the EU Habitat Directive (HD). High ecological status according to the WFD should mean high status according to the HD. To avoid any conflicts between different EU directives and national environmental objectives, surface waters protected as for example Natura 2000 sites should ideally show high ecological status according to the WFD. Also, high ecological status according to the WFD should imply the presence or potential for presence of red-listed species. Here, we studied the ecological status of 1014 Fennoscandian lakes (224 Norwegian, 491 Swedish and 299 Finnish lakes) according to the WFD and related it to the number of red-listed species per lake and to the status of the lakes as Natura 2000 areas. High ecological status according to the WFD did not mean high status according to the HD or according to national environmental objectives. In general, the number of red-listed species decreased with increased ecological quality ratios. In Norway 47%, in Sweden 78%, and in Finland 29% of lakes with red-listed species were classified as lakes of moderate or worse ecological status according to the WFD. In Sweden 39 of 68 studied Natura 2000 lakes had a moderate or poor ecological status according to the WFD. In Sweden and Norway, in contrast to Finland, macrophyte-based assessment systems are primarily a trophic index, i.e. penalising lakes with elevated phosphorous concentrations. The multimetric nature of the Finnish index probably contributes to the better agreement between the WFD assessment and the number of red-listed species in Finland compared to Sweden and Norway. In Sweden six of eight red-listed species occur in lakes with phosphorous concentrations considerably above reference conditions. Generally, it is assumed that biodiversity is favoured by intermediate nutrient concentrations. In addition, instead of phosphorous, Ca concentrations appear important for the occurrence of many redlisted species, especially for Charophytes. Rapid revision of the national indices is needed to increase compatibility between the two EU directives and to increase the agreement between the WFD and national environmental objectives.
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33. |
- Ecke, Frauke
(author)
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Drainage ditching at the catchment scale affects water quality and macrophyte occurrence in Swedish lakes
- 2009
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In: Freshwater Biology. - : Wiley. - 0046-5070 .- 1365-2427. ; 54:1, s. 119-126
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Journal article (peer-reviewed)abstract
- 1. We have limited knowledge of the effects of land use in general and of drainage ditching in particular on macrophyte communities in lakes. I quantified catchment land use, including drainage ditching, as well as water quality and the number of macrophyte species in 17 Swedish lakes in summer 2005.2. Land use within 1 km of the studied lakes was analysed in a geographic information system. The following variables were included: areas of forests, mires, agricultural land and urbanization, length of drainage ditches (classified according to the use of the land they drained), and shortest distance from lake to an urban area. To extract and analyse general trends in the data sets, redundancy analysis was used.3. Water quality was explained mainly by three land-use related variables: the lengths of agricultural, forest and mire ditches. The length of agricultural ditches was positively correlated with lake water conductivity, total dissolved solids, Ca, N and total organic carbon (TOC). The lengths of forest and mire ditches were positively correlated with lake water characteristics, especially TOC.4. The number of species representing different macrophyte life forms was explained by three environmental variables: conductivity, and lengths of forest and agricultural ditches. The numbers of isoetids, nymphaeids, elodeids and total obligate hydrophytes were negatively correlated with length of forest ditches. In contrast, the number of lemnids and helophytes was positively correlated with conductivity and length of agricultural ditches. Furthermore, the number of isoetids was exponentially related (negatively) to lengths of agricultural and forest ditches, indicating a threshold response to drainage ditch length.5. The results suggest that effects on water quality and macrophyte communities result from drainage ditching in the lake catchments rather than from land use itself. Given the total area of drainage-ditched land worldwide (millions of ha in Scandinavia alone), drainage ditching should be considered when evaluating environmental impacts on lake water quality and macrophyte occurrence and when determining reference conditions for catchment land use.
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34. |
- Ecke, Frauke
(author)
-
Effects of landscape patterns on small mammal abundance
- 2003
-
Doctoral thesis (other academic/artistic)abstract
- Several studies indicate a long-term decline in the numbers of voles in northern Fennoscandia. Altered land use and forest management practices have been proposed as possible causes of the decline. This doctorial thesis aimed to identify, on different spatial scales, landscape patterns that are important for the abundance of small mammals and that might be related to the decline. General trends and aspects of spatial habitat modelling were reviewed. Trapping data from three large extent monitoring programs were related to habitat factors on different spatial scales. For these analyses, a broad range of statistical and GIS (geographic information system) related methods was applied. On the microscale (trapping station, extent <= 10 m) and mesoscale (transect, length 90 m), structural habitat factors such as coarse and fine woody debris, umbrella vegetation and structural complexity of the forest floor were identified as important factors influencing small mammal abundance. Small mammal densities were related to the percentage landcover of vegetation types on the micro-, meso-, macro- (subarea/landscape, 1 x 1, 2.5 x 2.5 and 2 x 5 km) and regional scale (overall study area, 20 x 20 - 80 x 80 km). The spatial continuity (non- fragmentation) of old-growth pine forest patches on the landscape scale was positively related to the abundance of C. rufocanus, the species that showed the most pronounced long-term decline in numbers. The results of this thesis strongly suggest that altered land use might indeed be involved in the decline in numbers of voles in managed forest areas in northern Fennoscandia. To reveal and test responses of small mammals to changes in landscape patterns in more detail, this work proposes further application of large scale approaches. These approaches, e.g. the GIS-based prediction of the areas with currently high abundance of C. rufocanus can be tested by field sampling of the type applied in this thesis. Such approaches should consider the key aspects identified in the reviews on GIS-based habitat modelling, e.g. reconciling the scale of the population dynamics of small mammals with the scale (resolution and extent) of the input data, the application of different modelling approaches and the performance of sensitivity analysis.
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35. |
- Ecke, Frauke
(author)
-
Elements of lake macrophyte metacommunity structure: Global variation and community-environment relationships
- 2020
-
In: Limnology and Oceanography. - : Wiley. - 0024-3590 .- 1939-5590. ; 65, s. 2883-2895
-
Journal article (peer-reviewed)abstract
- 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.
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36. |
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37. |
- Ecke, Frauke, et al.
(author)
-
Europe-Wide Dampening of Population Cycles in Keystone Herbivores
- 2013
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In: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 340, s. 63-66
-
Journal article (peer-reviewed)abstract
- Suggestions of collapse in small herbivore cycles since the 1980s have raised concerns about the loss of essential ecosystem functions. Whether such phenomena are general and result from extrinsic environmental changes or from intrinsic process stochasticity is currently unknown. Using a large compilation of time series of vole abundances, we demonstrate consistent cycle amplitude dampening associated with a reduction in winter population growth, although regulatory processes responsible for cyclicity have not been lost. The underlying syndrome of change throughout Europe and grass-eating vole species suggests a common climatic driver. Increasing intervals of low-amplitude small herbivore population fluctuations are expected in the future, and these may have cascading impacts on trophic webs across ecosystems.
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38. |
- Ecke, Frauke, et al.
(author)
-
Evolutionary Relationships of Ljungan Virus Variants Circulating in Multi-Host Systems across Europe
- 2021
-
In: Viruses. - : MDPI AG. - 1999-4915. ; 13
-
Journal article (peer-reviewed)abstract
- The picornavirus named 'Ljungan virus' (LV, species Parechovirus B) has been detected in a dozen small mammal species from across Europe, but detailed information on its genetic diversity and host specificity is lacking. Here, we analyze the evolutionary relationships of LV variants circulating in free-living mammal populations by comparing the phylogenetics of the VP1 region (encoding the capsid protein and associated with LV serotype) and the 3D(pol) region (encoding the RNA polymerase) from 24 LV RNA-positive animals and a fragment of the 5 ' untranslated region (UTR) sequence (used for defining strains) in sympatric small mammals. We define three new VP1 genotypes: two in bank voles (Myodes glareolus) (genotype 8 from Finland, Sweden, France, and Italy, and genotype 9 from France and Italy) and one in field voles (Microtus arvalis) (genotype 7 from Finland). There are several other indications that LV variants are host-specific, at least in parts of their range. Our results suggest that LV evolution is rapid, ongoing and affected by genetic drift, purifying selection, spillover and host evolutionary history. Although recent studies suggest that LV does not have zoonotic potential, its widespread geographical and host distribution in natural populations of well-characterized small mammals could make it useful as a model for studying RNA virus evolution and transmission.
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39. |
- Ecke, Frauke, et al.
(author)
-
Geographical Distribution and Genetic Diversity of Bank Vole Hepaciviruses in Europe
- 2021
-
In: Viruses. - : MDPI AG. - 1999-4915. ; 13
-
Journal article (peer-reviewed)abstract
- The development of new diagnostic methods resulted in the discovery of novel hepaciviruses in wild populations of the bank vole (Myodes glareolus, syn. Clethrionomys glareolus). The naturally infected voles demonstrate signs of hepatitis similar to those induced by hepatitis C virus (HCV) in humans. The aim of the present research was to investigate the geographical distribution of bank vole-associated hepaciviruses (BvHVs) and their genetic diversity in Europe. Real-time reverse transcription polymerase chain reaction (RT-qPCR) screening revealed BvHV RNA in 442 out of 1838 (24.0%) bank voles from nine European countries and in one of seven northern red-backed voles (Myodes rutilus, syn. Clethrionomys rutilus). BvHV RNA was not found in any other small mammal species (n = 23) tested here. Phylogenetic and isolation-by-distance analyses confirmed the occurrence of both BvHV species (Hepacivirus F and Hepacivirus J) and their sympatric occurrence at several trapping sites in two countries. The broad geographical distribution of BvHVs across Europe was associated with their presence in bank voles of different evolutionary lineages. The extensive geographical distribution and high levels of genetic diversity of BvHVs, as well as the high population fluctuations of bank voles and occasional commensalism in some parts of Europe warrant future studies on the zoonotic potential of BvHVs.
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40. |
- Ecke, Frauke, et al.
(author)
-
Geographical Distribution of Ljungan Virus in Small Mammals in Europe
- 2020
-
In: Vector-Borne and Zoonotic Diseases. - : Mary Ann Liebert Inc. - 1530-3667 .- 1557-7759. ; 20, s. 692-702
-
Journal article (peer-reviewed)abstract
- Ljungan virus (LV), which belongs to the Parechovirus genus in the Picornaviridae family, was first isolated from bank voles (Myodes glareolus) in Sweden in 1998 and proposed as a zoonotic agent. To improve knowledge of the host association and geographical distribution of LV, tissues from 1685 animals belonging to multiple rodent and insectivore species from 12 European countries were screened for LV-RNA using reverse transcriptase (RT)-PCR. In addition, we investigated how the prevalence of LV-RNA in bank voles is associated with various intrinsic and extrinsic factors. We show that LV is widespread geographically, having been detected in at least one host species in nine European countries. Twelve out of 21 species screened were LV-RNA PCR positive, including, for the first time, the red vole (Myodes rutilus) and the root or tundra vole (Alexandromys formerly Microtus oeconomus), as well as in insectivores, including the bicolored white-toothed shrew (Crocidura leucodon) and the Valais shrew (Sorex antinorii). Results indicated that bank voles are the main rodent host for this virus (overall RT-PCR prevalence: 15.2%). Linear modeling of intrinsic and extrinsic factors that could impact LV prevalence showed a concave-down relationship between body mass and LV occurrence, so that subadults had the highest LV positivity, but LV in older animals was less prevalent. Also, LV prevalence was higher in autumn and lower in spring, and the amount of precipitation recorded during the 6 months preceding the trapping date was negatively correlated with the presence of the virus. Phylogenetic analysis on the 185 base pair species-specific sequence of the 5 ' untranslated region identified high genetic diversity (46.5%) between 80 haplotypes, although no geographical or host-specific patterns of diversity were detected.
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41. |
- Ecke, Frauke, et al.
(author)
-
Gifter i naturen skadar djuren
- 2020
-
In: Gifter och Miljö. - Stockholm : Naturvårdsverket. ; , s. 39-43
-
Journal article (pop. science, debate, etc.)abstract
- Bly är giftigt och kan direkt eller indirekt orsaka stora problem hos däggdjur och fåglar.I vissa fall kan blyförgiftning orsaka att de dör. Även om tillförseln av bly till naturen harminskat de senaste decennierna så återstår stora problem. Framför allt för en del rovfåglar och asätande däggdjur.
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42. |
- Ecke, Frauke
(author)
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Global patterns and determinants of lake macrophyte taxonomic, functional and phylogenetic beta diversity
- 2020
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In: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 723
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Journal article (peer-reviewed)abstract
- 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 nullmodels; 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 different spatial scales. (C) 2020 Elsevier B.V. All rights reserved.y
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43. |
- Ecke, Frauke
(author)
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Global patterns in the metacommunity structuring of lake macrophytes: regional variations and driving factors
- 2018
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In: Oecologia. - : Springer Science and Business Media LLC. - 0029-8549 .- 1432-1939. ; 188, s. 1167-1182
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Journal article (peer-reviewed)abstract
- We studied community-environment relationships of lake macrophytes at two metacommunity scales using data from 16 regions across the world. More specifically, we examined (a) whether the lake macrophyte communities respond similar to key local environmental factors, major climate variables and lake spatial locations in each of the regions (i.e., within-region approach) and (b) how well can explained variability in the community-environment relationships across multiple lake macrophyte metacommunities be accounted for by elevation range, spatial extent, latitude, longitude, and age of the oldest lake within each metacommunity (i.e., across-region approach). In the within-region approach, we employed partial redundancy analyses together with variation partitioning to investigate the relative importance of local variables, climate variables, and spatial location on lake macrophytes among the study regions. In the across-region approach, we used adjusted R-2 values of the variation partitioning to model the community-environment relationships across multiple metacommunities using linear regression and commonality analysis. We found that niche filtering related to local lake-level environmental conditions was the dominant force structuring macrophytes within metacommunities. However, our results also revealed that elevation range associated with climate (increasing temperature amplitude affecting macrophytes) and spatial location (likely due to dispersal limitation) was important for macrophytes based on the findings of the across-metacommunities analysis. These findings suggest that different determinants influence macrophyte metacommunities within different regions, thus showing context dependency. Moreover, our study emphasized that the use of a single metacommunity scale gives incomplete information on the environmental features explaining variation in macrophyte communities.
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44. |
- Ecke, Frauke
(author)
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Global variation in the beta diversity of lake macrophytes is driven by environmental heterogeneity rather than latitude
- 2017
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In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 44, s. 1758-1769
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Journal article (peer-reviewed)abstract
- Aim We studied global variation in beta diversity patterns of lake macrophytes using regional data from across the world. Specifically, we examined (1) how beta diversity of aquatic macrophytes is partitioned between species turnover and nestedness within each study region, and (2) which environmental characteristics structure variation in these beta diversity components.Location Global.Methods We used presence-absence data for aquatic macrophytes from 21 regions distributed around the world. We calculated pairwise-site and multiple-site beta diversity among lakes within each region using SOrensen dissimilarity index and partitioned it into turnover and nestedness coefficients. Beta regression was used to correlate the diversity coefficients with regional environmental characteristics.Results Aquatic macrophytes showed different levels of beta diversity within each of the 21 study regions, with species turnover typically accounting for the majority of beta diversity, especially in high-diversity regions. However, nestedness contributed 30-50% of total variation in macrophyte beta diversity in low-diversity regions. The most important environmental factor explaining the three beta diversity coefficients (total, species turnover and nestedness) was elevation range, followed by relative areal extent of freshwater, latitude and water alkalinity range.Main conclusions Our findings show that global patterns in beta diversity of lake macrophytes are caused by species turnover rather than by nestedness. These patterns in beta diversity were driven by natural environmental heterogeneity, notably variability in elevation range (also related to temperature variation) among regions. In addition, a greater range in alkalinity within a region, likely amplified by human activities, was also correlated with increased macrophyte beta diversity. These findings suggest that efforts to conserve aquatic macrophyte diversity should primarily focus on regions with large numbers of lakes that exhibit broad environmental gradients.
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48. |
- Ecke, Frauke, et al.
(author)
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Identification of landscape elements related to local declines of a boreal grey-sided vole population
- 2006
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In: Landscape Ecology. - : Springer Science and Business Media LLC. - 0921-2973 .- 1572-9761. ; 21:4, s. 485-497
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Journal article (peer-reviewed)abstract
- Several studies indicate a long-term decline in numbers of different species of voles in northern Fennoscandia. In boreal Sweden, the long-term decline is most pronounced in the grey-sided vole (Clethrionomys rufocanus). Altered forest landscape structure has been suggested as a possible cause of the decline. However, habitat responses of grey-sided voles at the landscape scale have never been studied. We analyzed such responses of this species in lowland forests in Västerbotten, northern Sweden. Cumulated spring densities representing 22 local time series from 1980-1999 were obtained by a landscape sampling design and were related to the surrounding landscape structure of 2.5×2.5 km plots centred on each of the 22 1-ha trapping plots. In accordance with general knowledge on local habitat preferences of grey-sided voles, our study supported the importance of habitat variables such as boulder fields and old-growth pine forest at the landscape scale. Densities were negatively related to clear cuts. Habitat associations were primarily those of landscape structure related to habitat fragmentation, distance between habitat patches and patch interspersion rather than habitat patch type quantity. Local densities of the grey-sided vole were positively and exponentially correlated with spatial contiguity (measured with the fragmentation index) of old-growth pine forest, indicating critical forest fragmentation thresholds. Our results indicate that altered land use might be involved in the long-term decline of the grey-sided vole in managed forest areas of Fennoscandia. We propose two further approaches to reveal and test responses of this species to changes in landscape structure.
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