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Propagule Pressure and Disturbance Drive the Invasion of Perennial False-Brome (Brachypodium sylvaticum)

Published online by Cambridge University Press:  20 January 2017

Laura A. V. Taylor*
Affiliation:
Department of Biology, Portland State University, P.O. Box 751, Portland, OR 97201
Mitchell B. Cruzan
Affiliation:
Department of Biology, Portland State University, P.O. Box 751, Portland, OR 97201
*
Corresponding author's E-mail: lauraavtaylor@gmail.com

Abstract

An ecosystem's invasibility is influenced by changes in biotic and abiotic resistances, which often occur due to shifts in the prevailing disturbance regime. The susceptibility of a community to intrusion by nonnative species may interact with propagule pressure to determine the extent of a biological invasion. We examined how propagule pressure, forest community structure, and disturbance interact to influence the invasibility of temperate Pacific Northwest forests by the newly invasive grass, perennial false-brome (Brachypodium sylvaticum). Our goal was to identify factors enabling shifts from establishment to population growth in B. sylvaticum populations at the edge of its expanding range. Ecological sampling methods were used to identify patterns in B. sylvaticum habitat. An inverse relationship between the amount of B. sylvaticum and all perennial vegetation types and soil litter depth was found, suggesting that disturbance might play a role in B. sylvaticum population establishment or growth. An experimental study was then performed to test the effects of disturbance, propagule pressure, and habitat on B. sylvaticum seedling establishment in sites where B. sylvaticum was already naturalized. We found evidence that disturbance of the soil and vegetation led to increased B. sylvaticum seedling recruitment within naturalized sites, especially where conditions of high propagule pressure and deciduous forest canopy existed. In contrast, B. sylvaticum populations dominated by coniferous forest canopy were much more invasible than deciduous forests and did not show increased seedling recruitment in response to our disturbance treatments. Our study shows how propagule pressure and plant community dynamics interact to alter the invasibility of Pacific Northwest forests allowing B. sylvaticum to transition from establishment to population growth thus allowing this weed to cause greater negative impacts on the ecosystem.

Type
Research Article
Copyright
Copyright © Weed Science Society of America 

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References

Literature Cited

Akaike, H (1974) New look at statistical-model identification. IEEE Trans Autom Control AC-19:716723 Google Scholar
Barbour, MG, Burk, JH, Pitts, WD, Gilliam, FS, Schwarts, MW (1998) Terrestrial Plant Ecology. 3rd edn. Menlo Park, CA Benjamin/Cummings. P 649 Google Scholar
Blakeley-Smith, M, Kaye, TN (2008) Mowing, Mulching and Seeding To Control False-Brome on the Eugene District, BLM, Oregon. Corvallis, OR Institute for Applied Ecology. 19 pGoogle Scholar
Britton-Simmons, KH, Abbott, KC (2008) Short- and long-term effects of disturbance and propagule pressure on a biological invasion. J Ecol 96:6877 Google Scholar
Catalan, P, Olmstead, RG (2000) Phylogenetic reconstruction of the genus Branchypodium P-Beauv. (Poaceae) from combined sequences of chloroplast ndhF gene and nuclear ITS. Plant Syst Evol 220:119 Google Scholar
Chambers, KL (1966) Notes on some grasses of the Pacific Coast. Madroño 18:250251 Google Scholar
Clark, GF, Johnston, EL (2009) Propagule pressure and disturbance interact to overcome biotic resistance of marine invertebrate communities. Oikos 118:16791686 Google Scholar
Colautti, RI, Grigorovich, IA, MacIsaac, HJ (2006) Propagule pressure: a null model for biological invasions. Biol Invasions 8:10231037 Google Scholar
Connell, JH (1979) Intermediate-disturbance hypothesis. Science 204:13451345 Google Scholar
Daehler, CC (2003) Performance comparisons of co-occurring native and alien invasive plants: implications for conservation and restoration. Annu Rev Ecol Syst 34:183211 Google Scholar
D'Antonio, CM, Levine, J, Thomsen, M (2001) Ecosystem resistance to invasion and the role of propagule supply: a California perspective. J Mediterr Ecol 2:233245 Google Scholar
Davis, MA, Grime, JP, Thompson, K (2000) Fluctuating resources in plant communities: a general theory of invasibility. J Ecol 88:528534 Google Scholar
Dietz, H, Edwards, PJ (2006) Recognition that causal processes change during plant invasion helps explain conflicts in evidence. Ecology 87:13591367 Google Scholar
Elton, CS (1958) The Ecology of Invasions by Animals and Plants. London Methuen 196 pGoogle Scholar
Eschtruth, AK, Battles, JJ (2009) Assessing the relative importance of disturbance, herbivory, diversity, and propagule pressure in exotic plant invasion. Ecol Monogr 79:265280 Google Scholar
False Brome Working Group (2009) False Brome Working Group. http://www.appliedeco.org/invasive-species-resources/FBWG. Accessed February 8, 2011Google Scholar
Frazer, GW, Canham, CD, Lertzman, KP (1999) Gap Light Analyzer (GLA): Imaging Software to Extract Canopy Structure and Gap Light Transmission Indices from True-Colour Fisheye Photographs: Users Manual and Program Documentation. Burnaby, BC, Canada, and Millbrook, NY Simon Fraser University and Institute of Ecosystem Studies 36 pGoogle Scholar
Grime, JP, Hodgson, JG, Hunt, R (1988) Comparative Plant Ecology: A Functional Approach to Common British Species. London Unwin Hyman 752 pGoogle Scholar
Heinken, T, Raudnitschka, D (2002) Do wild ungulates contribute to the dispersal of vascular plants in central European forests by epizoochory? A case study in NE Germany. Forstwissenschaftliches Centralblatt 121:179194 Google Scholar
Hitchcock, C, Cronquist, A, Ownbey, M, Thomson, J (1969) Vascular Plants of the Pacific Northwest, Part 1: Vascular Cryptograms, Gymnosperms, and Monocotyledons. Seattle University of Washington Press 914 pGoogle Scholar
Holmes, SE, Roy, BA, Reed, JP, Johnson, BJ (2010) Context-dependent pattern and process: The distribution and competitive dynamics of an invasive grass, Brachypodium sylvaticum . Bioll Invasions 12:23022318 Google Scholar
Holten, JI (1980) Distribution and ecology of Brachypodium sylvaticum, Bromus benekeni and Festuca altissima in central Norway. Blyttia 38:137144 Google Scholar
Johnstone, IM (1986) Plant invasion windows: a time-based classification of invasion potential. Biol Rev 61:369394 Google Scholar
Jongejans, E, Skarpaas, O, Tipping, PW, Shea, K (2007) Establishment and spread of founding populations of an invasive thistle: the role of competition and seed limitation. Biol Invasions 9:317325 Google Scholar
Kaye, TN, Blakeley-Smith, M (2006) False-brome (Brachypodium sylvaticum). Pages 8081 in Boersma, PD, Reichard, SE, van Buren, AN, eds. Invasive Species in the Pacific Northwest. Seattle University of Washington Press Google Scholar
Lebreton, JD, Burnham, KP, Clobert, J, Anderson, DR (1992) Modeling survival and testing biological hypotheses using marked animals — a unified approach with case-studies. Ecol Monogr 62:67118 Google Scholar
Levine, JM, D'Antonio, CM (1999) Elton revisited: a review of evidence linking diversity and invasibility. Oikos 87:1526 Google Scholar
Lockwood, JL, Cassey, P, Blackburn, T (2005) The role of propagule pressure in explaining species invasions. Trends Ecol Evol 20:223228 Google Scholar
Lockwood, JL, Cassey, P, Blackburn, TM (2009) The more you introduce the more you get: the role of colonization pressure and propagule pressure in invasion ecology. Divers Distrib 15:904910 Google Scholar
Lockwood, JL, Hoopes, MF, Marchetti, MP (2007) Invasion Ecology. Malden, MA Wiley-Blackwell 304 pGoogle Scholar
Lonsdale, WM (1999) Global patterns of plant invasions and the concept of invasibility. Ecology 80:15221536 Google Scholar
McGlone, CM, Sieg, CH, Kolb, TE (2011) Invasion resistance and persistence: established plants win, even with disturbance and high propagule pressure. Biol Invasions 13:291304 Google Scholar
Miller, NP, Matlack, GR (2010) Population expansion in an invasive grass, Microstegium vimineum: a test of the channelled diffusion model. Divers Distrib 16:816826 Google Scholar
Minton, MS, Mack, RN (2010) Naturalization of plant populations: the role of cultivation and population size and density. Oecologia 164:399409 Google Scholar
O'Brien, RM (2007) A caution regarding rules of thumb for variance inflation factors. Qual Quant 41:673690 Google Scholar
Otfinowski, R, Kenkel, NC (2010) Covariance between disturbance and soil resources dictates the invasibility of northern fescue prairies. Biol Invasions 12:13491361 Google Scholar
Peters, DPC, Yao, J, Gosz, JR (2006) Woody plant invasion at a semi-arid/arid transition zone: importance of ecosystem type to colonization and patch expansion. J Veg Sci 17:389396 Google Scholar
Prevey, JS, Germino, MJ, Huntly, NJ, Inouye, RS (2010) Exotic plants increase and native plants decrease with loss of foundation species in sagebrush steppe. Plant Ecol 207:3951 Google Scholar
R Development Core Team (2009) R: A Language and Environment for Statistical Computing. http://www.R-project.org. Accessed October 1, 2009Google Scholar
Ramakrishnan, AP, Musial, T, Cruzan, MB (2010) Shifting dispersal modes at an expanding species' range margin. Mol Ecol 19:11341146 Google Scholar
Richardson, DM, Pysek, P (2006) Plant invasions: merging the concepts of species invasiveness and community invasibility. Prog Phys Geogr 30:409431 Google Scholar
Rosenthal, DM, Ramakrishnan, AP, Cruzan, MB (2008) Evidence for multiple sources of invasion and intraspecific hybridization in Brachypodium sylvaticum (Hudson) Beauv. in North America. Mol Ecol 17:46574669 Google Scholar
Roy, BA, Güsewell, S, Coulson, T, Blaser, W, Policha, T, Stewart, J, Blaisdell, K (2011) Population regulation by enemies of the grass Brachypodium sylvaticum: demography in native and invaded ranges Ecology. Ecology 92:665675 Google Scholar
Schramm, JW, Ehrenfeld, JG (2010) Leaf litter and understory canopy shade limit the establishment, growth and reproduction of Microstegium vimineum. Biol Invasions 12:31953204 Google Scholar
Simberloff, D (2009) The role of propagule pressure in biological invasions. Annu Rev Ecol Evol Syst 40:81102 Google Scholar
Symstad, AJ (2000) A test of the effects of functional group richness and composition on grassland invasibility. Ecology 81:99109.Google Scholar
Tanentzap, AJ, Bazely, DR, Lafortezza, R (2010) Diversity-invasibility relationships across multiple scales in disturbed forest understoreys. Biol Invasions 12:21052116 Google Scholar
Taylor, LAV, Hasenkopf, EA, Cruzan, MB (2015) Barriers to invasive infilling by Brachypodium sylvaticum in Pacific Northwest forests. Biol Invasions. DOI: 10.1007/s10530-015-0871-x. 14 pGoogle Scholar
Tilman, D (1999) The ecological consequences of changes in biodiversity: a search for general principles. Ecology 80:14551474 Google Scholar
Wangen, SR, Webster, CR (2006) Potential for multiple lag phases during biotic invasions: reconstructing an invasion of the exotic tree Acer platanoides . J Appl Ecol 43:258268 Google Scholar
Warren, RJ, Ursell, T, Keiser, AD, Bradford, MA (2013) Habitat, dispersal and propagule pressure control exotic plant infilling within an invaded range. Ecosphere 4:112 Google Scholar