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2. Global plant trait relationships extend to the climatic extremes of the tundra biome

Author

Thomas, H. J. D., Bjorkman, A. D., Myers-Smith, I. H., Elmendorf, S. C., Kattge, J., Diaz, S., Vellend, M., Blok, D., Cornelissen, J. H. C., Forbes, B. C., Henry, G. H. R., Hollister, R. D., Normand, S., Prevéy, J. S., Rixen, C., Schaepman-Strub, G., Wilmking, M., Wipf, S., Cornwell, W. K., Beck, P. S. A., Georges, D., Goetz, S. J., Guay, K. C., Rüger, N., Soudzilovskaia, N. A., Spasojevic, M. J., Alatalo, J. M., Alexander, H. D., Anadon-Rosell, A., Angers-Blondin, S., te Beest, M., Berner, L. T., Björk, R. G., Buchwal, A., Buras, A., Carbognani, M., Christie, K. S., Collier, L. S., Cooper, E. J., Elberling, B., Eskelinen, A., Frei, E. R., Grau, O., Grogan, P., Hallinger, M., Heijmans, M. M. P. D., Hermanutz, L., Hudson, J. M. G., Johnstone, J. F., Hülber, K., Iturrate-Garcia, M., Iversen, C. M., Jaroszynska, F., Kaarlejarvi, E., Kulonen, A., Lamarque, L. J., Lantz, T. C., Lévesque, E., Little, C. J., Michelsen, A., Milbau, A., Nabe-Nielsen, J., Nielsen, S. S., Ninot, J. M., Oberbauer, S. F., Olofsson, J., Onipchenko, V. G., Petraglia, A., Rumpf, S. B., Shetti, R., Speed, J. D. M., Suding, K. N., Tape, K. D., Tomaselli, M., Trant, A. J., Treier, U. A., Tremblay, M., Venn, S. E., Vowles, T., Weijers, S., Wookey, P. A., Zamin, T. J., Bahn, M., Blonder, B., van Bodegom, P. M., Bond-Lamberty, B., Campetella, G., Cerabolini, B. E. L., Chapin, III, F. S., Craine, J. M., Dainese, M., Green, W. A., Jansen, S., Kleyer, M., Manning, P., Niinemets, Ü., Onoda, Y., Ozinga, W. A., Peñuelas, J., Poschlod, P., Reich, P. B., Sandel, B., Schamp, B. S., Sheremetiev, S. N., and de Vries, F. T.

Published
2020
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3. Biotic interactions mediate patterns of herbivore diversity in the Arctic

Author

Barrio, I. C., Bueno, C. G., Gartzia, M., Soininen, E. M., Christie, K. S., Speed, J. D. M., Ravolainen, V. T., Forbes, B. C., Gauthier, G., Horstkotte, T., Hoset, K. S., Høye, T. T., Jónsdóttir, I. S., Lévesque, E., Mörsdorf, M. A., Olofsson, J., Wookey, P. A., and Hik, D. S.

Published
2016

5. Global plant trait relationships extend to the climatic extremes of the tundra biome

Author

Spatial Ecology and Global Change, Environmental Sciences, Thomas, H. J. D., Bjorkman, A. D., Myers-Smith, I. H., Elmendorf, S. C., Kattge, J., Diaz, S., Vellend, M., Blok, D., Cornelissen, J. H. C., Forbes, B. C., Henry, G. H. R., Hollister, R. D., Normand, S., Prevéy, J. S., Rixen, C., Schaepman-Strub, G., Wilmking, M., Wipf, S., Cornwell, W. K., Beck, P. S. A., Georges, D., Goetz, S. J., Guay, K. C., Rüger, N., Soudzilovskaia, N. A., Spasojevic, M. J., Alatalo, J. M., Alexander, H. D., Anadon-Rosell, A., Angers-Blondin, S., te Beest, M., Berner, L. T., Björk, R. G., Buchwal, A., Buras, A., Carbognani, M., Christie, K. S., Collier, L. S., Cooper, E. J., Elberling, B., Eskelinen, A., Frei, E. R., Grau, O., Grogan, P., Hallinger, M., Heijmans, M. M. P. D., Hermanutz, L., Hudson, J. M. G., Johnstone, J. F., Hülber, K., Iturrate-Garcia, M., Iversen, C. M., Jaroszynska, F., Kaarlejarvi, E., Kulonen, A., Lamarque, L. J., Lantz, T. C., Lévesque, E., Little, C. J., Michelsen, A., Milbau, A., Nabe-Nielsen, J., Nielsen, S. S., Ninot, J. M., Oberbauer, S. F., Olofsson, J., Onipchenko, V. G., Petraglia, A., Rumpf, S. B., Shetti, R., Speed, J. D. M., Suding, K. N., Tape, K. D., Tomaselli, M., Trant, A. J., Treier, U. A., Tremblay, M., Venn, S. E., Vowles, T., Weijers, S., Wookey, P. A., Zamin, T. J., Bahn, M., Blonder, B., van Bodegom, P. M., Bond-Lamberty, B., Campetella, G., Cerabolini, B. E. L., Chapin, F. S., Craine, J. M., Dainese, M., Green, W. A., Jansen, S., Kleyer, M., Manning, P., Niinemets, Ü., Onoda, Y., Ozinga, W. A., Peñuelas, J., Poschlod, P., Reich, P. B., Sandel, B., Schamp, B. S., Sheremetiev, S. N., de Vries, F. T., Spatial Ecology and Global Change, Environmental Sciences, Thomas, H. J. D., Bjorkman, A. D., Myers-Smith, I. H., Elmendorf, S. C., Kattge, J., Diaz, S., Vellend, M., Blok, D., Cornelissen, J. H. C., Forbes, B. C., Henry, G. H. R., Hollister, R. D., Normand, S., Prevéy, J. S., Rixen, C., Schaepman-Strub, G., Wilmking, M., Wipf, S., Cornwell, W. K., Beck, P. S. A., Georges, D., Goetz, S. J., Guay, K. C., Rüger, N., Soudzilovskaia, N. A., Spasojevic, M. J., Alatalo, J. M., Alexander, H. D., Anadon-Rosell, A., Angers-Blondin, S., te Beest, M., Berner, L. T., Björk, R. G., Buchwal, A., Buras, A., Carbognani, M., Christie, K. S., Collier, L. S., Cooper, E. J., Elberling, B., Eskelinen, A., Frei, E. R., Grau, O., Grogan, P., Hallinger, M., Heijmans, M. M. P. D., Hermanutz, L., Hudson, J. M. G., Johnstone, J. F., Hülber, K., Iturrate-Garcia, M., Iversen, C. M., Jaroszynska, F., Kaarlejarvi, E., Kulonen, A., Lamarque, L. J., Lantz, T. C., Lévesque, E., Little, C. J., Michelsen, A., Milbau, A., Nabe-Nielsen, J., Nielsen, S. S., Ninot, J. M., Oberbauer, S. F., Olofsson, J., Onipchenko, V. G., Petraglia, A., Rumpf, S. B., Shetti, R., Speed, J. D. M., Suding, K. N., Tape, K. D., Tomaselli, M., Trant, A. J., Treier, U. A., Tremblay, M., Venn, S. E., Vowles, T., Weijers, S., Wookey, P. A., Zamin, T. J., Bahn, M., Blonder, B., van Bodegom, P. M., Bond-Lamberty, B., Campetella, G., Cerabolini, B. E. L., Chapin, F. S., Craine, J. M., Dainese, M., Green, W. A., Jansen, S., Kleyer, M., Manning, P., Niinemets, Ü., Onoda, Y., Ozinga, W. A., Peñuelas, J., Poschlod, P., Reich, P. B., Sandel, B., Schamp, B. S., Sheremetiev, S. N., and de Vries, F. T.

Published
2020

6. Traditional plant functional groups explain variation in economic but not size-related traits across the tundra biome

Author

Thomas, H. J. D., Myers-Smith, I. H., Bjorkman, A. D., Elmendorf, S. C., Blok, D., Cornelissen, J. H. C., Forbes, B. C., Hollister, R. D., Normand, S., Prevéy, J. S., Rixen, C., Schaepman-Strub, G., Wilmking, M., Wipf, S., Cornwell, W. K., Kattge, J., Goetz, S. J., Guay, K. C., Alatalo, J. M., Anadon-Rosell, A., Angers-Blondin, S., Berner, L. T., Björk, R. G., Buchwal, A., Buras, A., Carbognani, M., Christie, K., Siegwart Collier, L., Cooper, E. J., Eskelinen, A., Frei, E. R., Grau, O., Grogan, P., Hallinger, M., Heijmans, M. M. P. D., Hermanutz, L., Hudson, J. M. G., Hülber, K., Iturrate-Garcia, M., Iversen, C. M., Jaroszynska, F., Johnstone, J. F., Kaarlejärvi, E., Kulonen, A., Lamarque, L. J., Lévesque, E., Little, C. J., Michelsen, A., Milbau, A., Nabe-Nielsen, J., Nielsen, S. S., Ninot, J. M., Oberbauer, S. F., Olofsson, J., Onipchenko, V. G., Petraglia, A., Rumpf, S. B., Semenchuk, P. R., Soudzilovskaia, N. A., Spasojevic, M. J., Speed, J. D. M., Tape, K. D., te Beest, M., Tomaselli, M., Trant, A., Treier, U. A., Venn, S., Vowles, T., Weijers, S., Zamin, T., Atkin, O. K., Bahn, M., Blonder, B., Campetella, G., Cerabolini, B. E. L., Chapin III, F. S., Dainese, M., de Vries, F. T., Díaz, S., Green, W., Jackson, R. B., Manning, P., Niinemets, Ü., Ozinga, W. A., Peñuelas, J., Reich, P. B., Schamp, B., Sheremetev, S., van Bodegom, P. M., Spatial Ecology and Global Change, and Environmental Sciences

Subjects
vegetation change, plant traits, ecosystem function, food and beverages, tundra biome, community composition, plant functional types, plant functional groups, cluster analysis
Abstract

Aim Plant functional groups are widely used in community ecology and earth system modelling to describe trait variation within and across plant communities. However, this approach rests on the assumption that functional groups explain a large proportion of trait variation among species. We test whether four commonly used plant functional groups represent variation in six ecologically important plant traits. Location Tundra biome. Time period Data collected between 1964 and 2016. Major taxa studied 295 tundra vascular plant species. Methods We compiled a database of six plant traits (plant height, leaf area, specific leaf area, leaf dry matter content, leaf nitrogen, seed mass) for tundra species. We examined the variation in species-level trait expression explained by four traditional functional groups (evergreen shrubs, deciduous shrubs, graminoids, forbs), and whether variation explained was dependent upon the traits included in analysis. We further compared the explanatory power and species composition of functional groups to alternative classifications generated using post hoc clustering of species-level traits. Results Traditional functional groups explained significant differences in trait expression, particularly amongst traits associated with resource economics, which were consistent across sites and at the biome scale. However, functional groups explained 19% of overall trait variation and poorly represented differences in traits associated with plant size. Post hoc classification of species did not correspond well with traditional functional groups, and explained twice as much variation in species-level trait expression. Main conclusions Traditional functional groups only coarsely represent variation in well-measured traits within tundra plant communities, and better explain resource economic traits than size-related traits. We recommend caution when using functional group approaches to predict tundra vegetation change, or ecosystem functions relating to plant size, such as albedo or carbon storage. We argue that alternative classifications or direct use of specific plant traits could provide new insights for ecological prediction and modelling.

Published
2019

7. Traditional plant functional groups explain variation in economic but not size-related traits across the tundra biome

Author

Spatial Ecology and Global Change, Environmental Sciences, Thomas, H. J. D., Myers-Smith, I. H., Bjorkman, A. D., Elmendorf, S. C., Blok, D., Cornelissen, J. H. C., Forbes, B. C., Hollister, R. D., Normand, S., Prevéy, J. S., Rixen, C., Schaepman-Strub, G., Wilmking, M., Wipf, S., Cornwell, W. K., Kattge, J., Goetz, S. J., Guay, K. C., Alatalo, J. M., Anadon-Rosell, A., Angers-Blondin, S., Berner, L. T., Björk, R. G., Buchwal, A., Buras, A., Carbognani, M., Christie, K., Siegwart Collier, L., Cooper, E. J., Eskelinen, A., Frei, E. R., Grau, O., Grogan, P., Hallinger, M., Heijmans, M. M. P. D., Hermanutz, L., Hudson, J. M. G., Hülber, K., Iturrate-Garcia, M., Iversen, C. M., Jaroszynska, F., Johnstone, J. F., Kaarlejärvi, E., Kulonen, A., Lamarque, L. J., Lévesque, E., Little, C. J., Michelsen, A., Milbau, A., Nabe-Nielsen, J., Nielsen, S. S., Ninot, J. M., Oberbauer, S. F., Olofsson, J., Onipchenko, V. G., Petraglia, A., Rumpf, S. B., Semenchuk, P. R., Soudzilovskaia, N. A., Spasojevic, M. J., Speed, J. D. M., Tape, K. D., te Beest, M., Tomaselli, M., Trant, A., Treier, U. A., Venn, S., Vowles, T., Weijers, S., Zamin, T., Atkin, O. K., Bahn, M., Blonder, B., Campetella, G., Cerabolini, B. E. L., Chapin III, F. S., Dainese, M., de Vries, F. T., Díaz, S., Green, W., Jackson, R. B., Manning, P., Niinemets, Ü., Ozinga, W. A., Peñuelas, J., Reich, P. B., Schamp, B., Sheremetev, S., van Bodegom, P. M., Spatial Ecology and Global Change, Environmental Sciences, Thomas, H. J. D., Myers-Smith, I. H., Bjorkman, A. D., Elmendorf, S. C., Blok, D., Cornelissen, J. H. C., Forbes, B. C., Hollister, R. D., Normand, S., Prevéy, J. S., Rixen, C., Schaepman-Strub, G., Wilmking, M., Wipf, S., Cornwell, W. K., Kattge, J., Goetz, S. J., Guay, K. C., Alatalo, J. M., Anadon-Rosell, A., Angers-Blondin, S., Berner, L. T., Björk, R. G., Buchwal, A., Buras, A., Carbognani, M., Christie, K., Siegwart Collier, L., Cooper, E. J., Eskelinen, A., Frei, E. R., Grau, O., Grogan, P., Hallinger, M., Heijmans, M. M. P. D., Hermanutz, L., Hudson, J. M. G., Hülber, K., Iturrate-Garcia, M., Iversen, C. M., Jaroszynska, F., Johnstone, J. F., Kaarlejärvi, E., Kulonen, A., Lamarque, L. J., Lévesque, E., Little, C. J., Michelsen, A., Milbau, A., Nabe-Nielsen, J., Nielsen, S. S., Ninot, J. M., Oberbauer, S. F., Olofsson, J., Onipchenko, V. G., Petraglia, A., Rumpf, S. B., Semenchuk, P. R., Soudzilovskaia, N. A., Spasojevic, M. J., Speed, J. D. M., Tape, K. D., te Beest, M., Tomaselli, M., Trant, A., Treier, U. A., Venn, S., Vowles, T., Weijers, S., Zamin, T., Atkin, O. K., Bahn, M., Blonder, B., Campetella, G., Cerabolini, B. E. L., Chapin III, F. S., Dainese, M., de Vries, F. T., Díaz, S., Green, W., Jackson, R. B., Manning, P., Niinemets, Ü., Ozinga, W. A., Peñuelas, J., Reich, P. B., Schamp, B., Sheremetev, S., and van Bodegom, P. M.

Published
2019

8. Tundra Trait Team: A database of plant traits spanning the tundra biome

Author

Bjorkman, A. D., Myers-Smith, I. H., Elmendorf, S. C., Normand, S., Thomas, H. J. D., Alatalo, J. M., Alexander, H., Anadon-Rosell, A., Angers-Blondin, S., Bai, Y., Baruah, G., te Beest, M., Berner, L., Björk, R. G., Blok, D., Bruelheide, H., Buchwal, A., Buras, A., Carbognani, M., Christie, K., Collier, L. S., Cooper, E. J., Cornelissen, J. H. C., Dickinson, K. J. M., Dullinger, S., Elberling, B., Eskelinen, A., Forbes, B. C., Frei, E. R., Iturrate-Garcia, M., Good, M. K., Grau, O., Green, P., Greve, M., Grogan, P., Haider, S., Hájek, T., Hallinger, M., Happonen, K., Harper, K. A., Heijmans, M. M. P. D., Henry, G. H. R., Hermanutz, L., Hewitt, R. E., Hollister, R. D., Hudson, J., Hülber, K., Iversen, C. M., Jaroszynska, F., Jiménez-Alfaro, B., Johnstone, J., Jorgensen, R. H., Kaarlejärvi, E., Klady, R., Klimešová, J., Korsten, A., Kuleza, S., Kulonen, A., Lamarque, L. J., Lantz, T., Lavalle, A., Lembrechts, J. J., Lévesque, E., Little, C. J., Luoto, M., Macek, P., Mack, M. C., Mathakutha, R., Michelsen, A., Milbau, A., Molau, U., Morgan, J. W., Mörsdorf, M. A., Nabe-Nielsen, J., Nielsen, S. S., Ninot, J. M., Oberbauer, S. F., Olofsson, J., Onipchenko, V. G., Petraglia, A., Pickering, C., Prevéy, J. S., Rixen, C., Rumpf, S. B., Schaepman-Strub, G., Semenchuk, P., Shetti, R., Soudzilovskaia, N. A., Spasojevic, M. J., Speed, J. D. M., Street, L. E., Suding, K., Tape, K. D., Tomaselli, M., Trant, A., Treier, U. A., Tremblay, J. P., Tremblay, M., Venn, S., Virkkala, A. M., Vowles, T., Weijers, S., Wilmking, M., Wipf, S., Zamin, T., Bjorkman, A. D., Myers-Smith, I. H., Elmendorf, S. C., Normand, S., Thomas, H. J. D., Alatalo, J. M., Alexander, H., Anadon-Rosell, A., Angers-Blondin, S., Bai, Y., Baruah, G., te Beest, M., Berner, L., Björk, R. G., Blok, D., Bruelheide, H., Buchwal, A., Buras, A., Carbognani, M., Christie, K., Collier, L. S., Cooper, E. J., Cornelissen, J. H. C., Dickinson, K. J. M., Dullinger, S., Elberling, B., Eskelinen, A., Forbes, B. C., Frei, E. R., Iturrate-Garcia, M., Good, M. K., Grau, O., Green, P., Greve, M., Grogan, P., Haider, S., Hájek, T., Hallinger, M., Happonen, K., Harper, K. A., Heijmans, M. M. P. D., Henry, G. H. R., Hermanutz, L., Hewitt, R. E., Hollister, R. D., Hudson, J., Hülber, K., Iversen, C. M., Jaroszynska, F., Jiménez-Alfaro, B., Johnstone, J., Jorgensen, R. H., Kaarlejärvi, E., Klady, R., Klimešová, J., Korsten, A., Kuleza, S., Kulonen, A., Lamarque, L. J., Lantz, T., Lavalle, A., Lembrechts, J. J., Lévesque, E., Little, C. J., Luoto, M., Macek, P., Mack, M. C., Mathakutha, R., Michelsen, A., Milbau, A., Molau, U., Morgan, J. W., Mörsdorf, M. A., Nabe-Nielsen, J., Nielsen, S. S., Ninot, J. M., Oberbauer, S. F., Olofsson, J., Onipchenko, V. G., Petraglia, A., Pickering, C., Prevéy, J. S., Rixen, C., Rumpf, S. B., Schaepman-Strub, G., Semenchuk, P., Shetti, R., Soudzilovskaia, N. A., Spasojevic, M. J., Speed, J. D. M., Street, L. E., Suding, K., Tape, K. D., Tomaselli, M., Trant, A., Treier, U. A., Tremblay, J. P., Tremblay, M., Venn, S., Virkkala, A. M., Vowles, T., Weijers, S., Wilmking, M., Wipf, S., and Zamin, T.

Abstract

Motivation: The Tundra Trait Team (TTT) database includes field-based measurements of key traits related to plant form and function at multiple sites across the tundra biome. This dataset can be used to address theoretical questions about plant strategy and trade-offs, trait–environment relationships and environmental filtering, and trait variation across spatial scales, to validate satellite data, and to inform Earth system model parameters. Main types of variable contained: The database contains 91,970 measurements of 18 plant traits. The most frequently measured traits (> 1,000 observations each) include plant height, leaf area, specific leaf area, leaf fresh and dry mass, leaf dry matter content, leaf nitrogen, carbon and phosphorus content, leaf C:N and N:P, seed mass, and stem specific density. Spatial location and grain: Measurements were collected in tundra habitats in both the Northern and Southern Hemispheres, including Arctic sites in Alaska, Canada, Greenland, Fennoscandia and Siberia, alpine sites in the European Alps, Colorado Rockies, Caucasus, Ural Mountains, Pyrenees, Australian Alps, and Central Otago Mountains (New Zealand), and sub-Antarctic Marion Island. More than 99% of observations are georeferenced. Time period and grain: All data were collected between 1964 and 2018. A small number of sites have repeated trait measurements at two or more time periods. Major taxa and level of measurement: Trait measurements were made on 978 terrestrial vascular plant species growing in tundra habitats. Most observations are on individuals (86%), while the remainder represent plot or site means or maximums per species. Software format: csv file and GitHub repository with data cleaning scripts in R; contribution to TRY plant trait database (www.try-db.org) to be included in the next version release.

Published
2018

9. Traditional plant functional groups explain variation in economic but not size‐related traits across the tundra biome

Author

Thomas, H. J. D., primary, Myers‐Smith, I. H., additional, Bjorkman, A. D., additional, Elmendorf, S. C., additional, Blok, D., additional, Cornelissen, J. H. C., additional, Forbes, B. C., additional, Hollister, R. D., additional, Normand, S., additional, Prevéy, J. S., additional, Rixen, C., additional, Schaepman‐Strub, G., additional, Wilmking, M., additional, Wipf, S., additional, Cornwell, W. K., additional, Kattge, J., additional, Goetz, S. J., additional, Guay, K. C., additional, Alatalo, J. M., additional, Anadon‐Rosell, A., additional, Angers‐Blondin, S., additional, Berner, L. T., additional, Björk, R. G., additional, Buchwal, A., additional, Buras, A., additional, Carbognani, M., additional, Christie, K., additional, Siegwart Collier, L., additional, Cooper, E. J., additional, Eskelinen, A., additional, Frei, E. R., additional, Grau, O., additional, Grogan, P., additional, Hallinger, M., additional, Heijmans, M. M. P. D., additional, Hermanutz, L., additional, Hudson, J. M. G., additional, Hülber, K., additional, Iturrate‐Garcia, M., additional, Iversen, C. M., additional, Jaroszynska, F., additional, Johnstone, J. F., additional, Kaarlejärvi, E., additional, Kulonen, A., additional, Lamarque, L. J., additional, Lévesque, E., additional, Little, C. J., additional, Michelsen, A., additional, Milbau, A., additional, Nabe‐Nielsen, J., additional, Nielsen, S. S., additional, Ninot, J. M., additional, Oberbauer, S. F., additional, Olofsson, J., additional, Onipchenko, V. G., additional, Petraglia, A., additional, Rumpf, S. B., additional, Semenchuk, P. R., additional, Soudzilovskaia, N. A., additional, Spasojevic, M. J., additional, Speed, J. D. M., additional, Tape, K. D., additional, te Beest, M., additional, Tomaselli, M., additional, Trant, A., additional, Treier, U. A., additional, Venn, S., additional, Vowles, T., additional, Weijers, S., additional, Zamin, T., additional, Atkin, O. K., additional, Bahn, M., additional, Blonder, B., additional, Campetella, G., additional, Cerabolini, B. E. L., additional, Chapin III, F. S., additional, Dainese, M., additional, de Vries, F. T., additional, Díaz, S., additional, Green, W., additional, Jackson, R. B., additional, Manning, P., additional, Niinemets, Ü., additional, Ozinga, W. A., additional, Peñuelas, J., additional, Reich, P. B., additional, Schamp, B., additional, Sheremetev, S., additional, and van Bodegom, P. M., additional

Published
2018
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11. Effects of hydropeaking on benthic invertebrate community composition in two central Norwegian rivers.

Author

Kjærstad, G., Arnekleiv, J. V., Speed, J. D. M., and Herland, A. K.

Subjects
BIOTIC communities, INVERTEBRATES, CHIRONOMIDAE, BAETIS, OLIGOCHAETA
Abstract

Abstract: Hydropower regulations can have dramatic impacts on river ecological communities. The operation of hydropower stations is related to power demands, but their releases in the receiving water body causes sudden changes in flow, which in turn affect the biota. The effects of such flow variations on benthic invertebrates is not fully understood. Here, we studied the effects of duration and intensity of hydropeaking on benthic invertebrates in two rivers over a 3.5‐year period. We used both quantitative (Surber) and semiquantitative (kick samples) sampling methods to compare the ramping zone with the permanently water covered zone downstream of the hydropower plant, and with corresponding unaffected upstream areas. The ramping zone had a different invertebrate community composition and lower benthic density than other areas, especially after hydropeaking. Mayflies and chironomids were most negatively affected by hydropeaking and oligochaetes largely unaffected. Chironomids and the mayfly Baetis rhodani were able to recolonize the ramping zone and almost reach densities similar to deeper areas within 48 days following hydropeaking. The relative abundance of filter feeders tended to increase and gatherers/collectors tended to decrease from the ramping zone towards the deep, permanently water covered areas. In corresponding areas upstream of the power plant, the relative abundance of different functional feeding groups was the same in the mid‐channel and shore sites. Our study shows that hydropeaking has clear impacts on the functional structure of benthic invertebrates below the power plants. The ecological impact of hydropeaking on invertebrate communities should thus be taken into account, for example, by reducing the amplitude and duration of flow fluctuations. [ABSTRACT FROM AUTHOR]

Published
2018
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15. Effects of Three Consecutive Rotenone Treatments on the Benthic Macroinvertebrate Fauna of the River Ogna, Central Norway.

Author

Kjærstad, G., Arnekleiv, J. V., and Speed, J. D. M.

Subjects
ROTENONE, AQUATIC invertebrates, GROUNDFISHES, WILDLIFE recovery, RIVERS
Abstract

The effects of piscicides on aquatic invertebrates are often studied after one treatment, even though piscicides may be repeatedly applied within river management. Here we investigate the impacts of repeated piscidie treatment on riverine benthic invertebrates. The River Ogna, Norway, was treated with rotenone three times over a 16-month period. The two first treatments caused temporary density reduction of a few rotenone sensitive benthic invertebrate taxa. Effects of the third treatment were variable with some taxa unaffected while all Plecoptera, were locally extinct. The toxic effect of rotenone increases with water temperature and high water temperature (20 °C) combined with high rotenone concentration was probably the main reason why the benthic community in the third treatment was more negatively affected than during the two previous treatments (4 and 8 °C). Eight months after the treatment benthic densities had not reached pre-treatment levels, but most taxa had recolonized the treated area within a year. Our data suggest that the severe effects of the third treatment were not influenced by the two former ones. This implies that the timing of piscicide treatment has a greater impact on the benthic invertebrate community than the number of treatments. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Published
2016
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16. Continuous and discontinuous variation in ecosystem carbon stocks with elevation across a treeline ecotone.

Author

Speed, J. D. M., Martinsen, V., Hester, A. J., Holand, Ø., Mulder, J., Mysterud, A., and Austrheim, G.

Subjects
TIMBERLINE, ECOTONES, BIOLOGICAL variation, CLIMATE change, CARBON content of plants, FORESTS & forestry
Abstract

Treelines differentiate vastly contrasting ecosystems: open tundra from closed forest. Treeline advance has implications for the climate system due to the impact of the transition from tundra to forest ecosystem on carbon (C) storage and albedo. Treeline advance has been seen to increase above-ground C stocks as low vegetation is replaced with trees, but decrease organic soil C stocks as old carbon is decomposed. However, studies comparing across the treeline typically do not account for elevational variation within the ecotone. Here we sample ecosystem C stocks along an elevational gradient (970 to 1300m), incorporating a large-scale and long-term livestock grazing experiment, in the Southern Norwegian mountains. We investigate whether there are continuous or discontinuous changes in C storage across the treeline ecotone, and whether these are modulated by grazing. We find that vegetation C stock decreases with elevation, with a clear breakpoint between the forest line and treeline above which the vegetation C stock is constant. In contrast, C stocks in organic surface horizons of the soil increase linearly with elevation within the study's elevational range, whereas C stocks in mineral soil horizons are unrelated to elevation. Total ecosystem C stocks also showed a discontinuous elevational pattern, increasing with elevation above the treeline (8 gm-2 m-1 increase in elevation), but decreasing with elevation below the forest line (-15 gm-2 m-1 increase in elevation), such that ecosystem C storage reaches a minimum between the forest line and treeline. We did not find any effect of short-term (12 years) grazing on the elevational patterns. Our findings demonstrate that patterns of C storage across the treeline are complex, and should be taken account of when estimating ecosystem C storage with shifting treelines. [ABSTRACT FROM AUTHOR]

Published
2014
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17. Do Nitrogen Concentration and Forage Quality of the Moss Racomitrium lanuginosumIncrease with Latitude?

Author

Speed, J. D. M., van der Wal, R., and Woodin, S. J.

Abstract

Mosses are an important component of high latitude ecosystems, contributing the majority of the plant biomass in many communities. In Arctic regions mosses also form a substantial part of the diet of many herbivore species. This may reflect either the availability of moss or its quality as forage. Here we test whether the nitrogen concentration and forage quality of the moss Racomitrium lanuginosumincrease with latitude and discuss the findings with reference to herbivore utilisation of moss in the Arctic. In contrast to vascular plants, moss nitrogen concentration significantly decreased with latitude (P<.01), in line with estimates of N deposition at the sampling sites. In addition, no evidence of an increase in nutritional quality of moss with latitude was observed; thus, this study suggests that the utilisation of moss by herbivores in arctic ecosystems maybe a function of their relatively high biomass rather than their quality as forage.

Published
2009
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18. Traditional plant functional groups explain variation in economic but not size-related traits across the tundra biome.

Author

Thomas HJD, Myers-Smith IH, Bjorkman AD, Elmendorf SC, Blok D, Cornelissen JHC, Forbes BC, Hollister RD, Normand S, Prevéy JS, Rixen C, Schaepman-Strub G, Wilmking M, Wipf S, Cornwell WK, Kattge J, Goetz SJ, Guay KC, Alatalo JM, Anadon-Rosell A, Angers-Blondin S, Berner LT, Björk RG, Buchwal A, Buras A, Carbognani M, Christie K, Siegwart Collier L, Cooper EJ, Eskelinen A, Frei ER, Grau O, Grogan P, Hallinger M, Heijmans MMPD, Hermanutz L, Hudson JMG, Hülber K, Iturrate-Garcia M, Iversen CM, Jaroszynska F, Johnstone JF, Kaarlejärvi E, Kulonen A, Lamarque LJ, Lévesque E, Little CJ, Michelsen A, Milbau A, Nabe-Nielsen J, Nielsen SS, Ninot JM, Oberbauer SF, Olofsson J, Onipchenko VG, Petraglia A, Rumpf SB, Semenchuk PR, Soudzilovskaia NA, Spasojevic MJ, Speed JDM, Tape KD, Te Beest M, Tomaselli M, Trant A, Treier UA, Venn S, Vowles T, Weijers S, Zamin T, Atkin OK, Bahn M, Blonder B, Campetella G, Cerabolini BEL, Chapin Iii FS, Dainese M, de Vries FT, Díaz S, Green W, Jackson RB, Manning P, Niinemets Ü, Ozinga WA, Peñuelas J, Reich PB, Schamp B, Sheremetev S, and van Bodegom PM

Abstract

Aim: Plant functional groups are widely used in community ecology and earth system modelling to describe trait variation within and across plant communities. However, this approach rests on the assumption that functional groups explain a large proportion of trait variation among species. We test whether four commonly used plant functional groups represent variation in six ecologically important plant traits., Location: Tundra biome., Time Period: Data collected between 1964 and 2016., Major Taxa Studied: 295 tundra vascular plant species., Methods: We compiled a database of six plant traits (plant height, leaf area, specific leaf area, leaf dry matter content, leaf nitrogen, seed mass) for tundra species. We examined the variation in species-level trait expression explained by four traditional functional groups (evergreen shrubs, deciduous shrubs, graminoids, forbs), and whether variation explained was dependent upon the traits included in analysis. We further compared the explanatory power and species composition of functional groups to alternative classifications generated using post hoc clustering of species-level traits., Results: Traditional functional groups explained significant differences in trait expression, particularly amongst traits associated with resource economics, which were consistent across sites and at the biome scale. However, functional groups explained 19% of overall trait variation and poorly represented differences in traits associated with plant size. Post hoc classification of species did not correspond well with traditional functional groups, and explained twice as much variation in species-level trait expression., Main Conclusions: Traditional functional groups only coarsely represent variation in well-measured traits within tundra plant communities, and better explain resource economic traits than size-related traits. We recommend caution when using functional group approaches to predict tundra vegetation change, or ecosystem functions relating to plant size, such as albedo or carbon storage. We argue that alternative classifications or direct use of specific plant traits could provide new insights for ecological prediction and modelling.

Published
2019
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