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Ibáñez I, Petri L, Barnett DT, Beaury EM, Blumenthal DM, Corbin JD, Diez J, Dukes JS, Early R, Pearse IS, Sorte CJB, Vilà M, Bradley B. Combining local, landscape, and regional geographies to assess plant community vulnerability to invasion impact. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2023; 33:e2821. [PMID: 36806368 DOI: 10.1002/eap.2821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 11/29/2022] [Accepted: 01/10/2023] [Indexed: 06/02/2023]
Abstract
Invasive species science has focused heavily on the invasive agent. However, management to protect native species also requires a proactive approach focused on resident communities and the features affecting their vulnerability to invasion impacts. Vulnerability is likely the result of factors acting across spatial scales, from local to regional, and it is the combined effects of these factors that will determine the magnitude of vulnerability. Here, we introduce an analytical framework that quantifies the scale-dependent impact of biological invasions on native richness from the shape of the native species-area relationship (SAR). We leveraged newly available, biogeographically extensive vegetation data from the U.S. National Ecological Observatory Network to assess plant community vulnerability to invasion impact as a function of factors acting across scales. We analyzed more than 1000 SARs widely distributed across the USA along environmental gradients and under different levels of non-native plant cover. Decreases in native richness were consistently associated with non-native species cover, but native richness was compromised only at relatively high levels of non-native cover. After accounting for variation in baseline ecosystem diversity, net primary productivity, and human modification, ecoregions that were colder and wetter were most vulnerable to losses of native plant species at the local level, while warmer and wetter areas were most susceptible at the landscape level. We also document how the combined effects of cross-scale factors result in a heterogeneous spatial pattern of vulnerability. This pattern could not be predicted by analyses at any single scale, underscoring the importance of accounting for factors acting across scales. Simultaneously assessing differences in vulnerability between distinct plant communities at local, landscape, and regional scales provided outputs that can be used to inform policy and management aimed at reducing vulnerability to the impact of plant invasions.
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Affiliation(s)
- Inés Ibáñez
- School for Environment and Sustainability, University of Michigan, Ann Arbor, Michigan, USA
| | - Laís Petri
- School for Environment and Sustainability, University of Michigan, Ann Arbor, Michigan, USA
| | - David T Barnett
- Battelle, National Ecological Observatory Network, Boulder, Colorado, USA
| | - Evelyn M Beaury
- Organismic and Evolutionary Biology, University of Massachusetts Amherst, Amherst, Massachusetts, USA
| | - Dana M Blumenthal
- USDA-ARS Rangeland Resources & Systems Research Unit, Fort Collins, Colorado, USA
| | - Jeffrey D Corbin
- Department of Biological Sciences, Union College, Schenectady, New York, USA
| | - Jeffrey Diez
- Institute of Ecology and Evolution, Department of Biology, University of Oregon, Eugene, Oregon, USA
| | - Jeffrey S Dukes
- Department of Global Ecology, Carnegie Institution for Science, Stanford, California, USA
| | - Regan Early
- Centre for Ecology and Conservation, University of Exeter Penryn Campus, Penryn, UK
| | - Ian S Pearse
- U.S. Geological Survey, Fort Collins Science Center, Fort Collins, Colorado, USA
| | - Cascade J B Sorte
- Department of Ecology and Evolutionary Biology, University of California, Irvine, California, USA
| | - Montserrat Vilà
- Estación Biológica de Doñana (EBD-CSIC), Sevilla, Spain
- Department of Plant Biology and Ecology, University of Sevilla, Sevilla, Spain
| | - Bethany Bradley
- Department of Environmental Conservation, University of Massachusetts Amherst, Amherst, Massachusetts, USA
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Zhang DJ, Qi Q, Tong SZ. Growth of Carex Tussocks as a Response of Flooding Depth and Tussock Patterning and Size in Temperate Sedge Wetland, Northeast China. RUSS J ECOL+ 2020. [DOI: 10.1134/s1067413620020137] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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3
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Variations in herbaceous vegetation structures and vegetation–environment relationships from floodplain to terrace along a large semi-humid river. Ecol Res 2018. [DOI: 10.1007/s11284-018-1619-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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Germain RM, Strauss SY, Gilbert B. Experimental dispersal reveals characteristic scales of biodiversity in a natural landscape. Proc Natl Acad Sci U S A 2017; 114:4447-4452. [PMID: 28416694 PMCID: PMC5410805 DOI: 10.1073/pnas.1615338114] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Ecological theory posits that dispersal among habitat patches links local communities and is a key "regional" process that maintains biological diversity. However, manipulations required to experimentally test regional processes are infeasible for most systems, and thus more work is needed to detect the scales at which regional processes manifest and their overall effect on diversity. In a Californian grassland, a hotspot for global biodiversity, we used a seed vacuum to increase dispersal at spatial scales varying from 1 m to 10 km while maintaining a realistic spatial structure of species pools and environmental conditions. We found that dispersal limitation has a profound influence on diversity; species richness increased with the spatial scale of seed mixing, doubling in plots that received seed from large (≥5 km) compared with small (≤5 m) scales. This increase in diversity corresponded to an increase in how well species distributions were explained by environmental conditions, from modest at small scales (R2 = 0.34) to strong at large scales (R2 = 0.52). Responses to the spatial scale of seed mixing were nonlinear, with no differences below 5 m or above 5 km. Nonlinearities were explained by homogeneity of environmental conditions below 5 m and by a lack of additional variation in the species pool above 5 km. Our approach of manipulating natural communities at different spatial scales reveals (i) nonlinear transitions in the importance of environmental sorting and dispersal, and (ii) the negative effects of dispersal limitation on local diversity, consistent with previous research suggesting that large numbers of species are headed toward regional extinction.
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Affiliation(s)
- Rachel M Germain
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, ON, Canada M5S 3G5;
| | - Sharon Y Strauss
- Department of Evolution and Ecology, University of California, Davis, CA 95616
| | - Benjamin Gilbert
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, ON, Canada M5S 3G5
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Tabacchi E, Planty-Tabacchi AM. Exotic and native plant community distributions within complex riparian landscapes: A positive correlation. ECOSCIENCE 2016. [DOI: 10.2980/i1195-6860-12-3-412.1] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Belter PR, Cahill JF. Disentangling root system responses to neighbours: identification of novel root behavioural strategies. AOB PLANTS 2015; 7:plv059. [PMID: 26019230 PMCID: PMC4512042 DOI: 10.1093/aobpla/plv059] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Accepted: 05/12/2015] [Indexed: 05/14/2023]
Abstract
Plants live in a social environment, with interactions among neighbours a ubiquitous aspect of life. Though many of these interactions occur in the soil, our understanding of how plants alter root growth and the patterns of soil occupancy in response to neighbours is limited. This is in contrast to a rich literature on the animal behavioural responses to changes in the social environment. For plants, root behavioural changes that alter soil occupancy patterns can influence neighbourhood size and the frequency or intensity of competition for soil resources; issues of fundamental importance to understanding coexistence and community assembly. Here we report a large comparative study in which individuals of 20 species were grown with and without each of two neighbour species. Through repeated root visualization and analyses, we quantified many putative root behaviours, including the extent to which each species altered aspects of root system growth (e.g. rooting breadth, root length, etc.) in response to neighbours. Across all species, there was no consistent behavioural response to neighbours (i.e. no general tendencies towards root over-proliferation nor avoidance). However, there was a substantial interspecific variation showing a continuum of behavioural variation among the 20 species. Multivariate analyses revealed two novel and predominant root behavioural strategies: (i) size-sensitivity, in which focal plants reduced their overall root system size in response to the presence of neighbours, and (ii) location-sensitivity, where focal plants adjusted the horizontal and vertical placement of their roots in response to neighbours. Of these, size-sensitivity represents the commonly assumed response to competitive encounters-reduced growth. However, location sensitivity is not accounted for in classic models and concepts of plant competition, though it is supported from recent work in plant behavioural ecology. We suggest that these different strategies could have important implications for the ability of a plant to persist in the face of strong competitors, and that location sensitivity may be a critical behavioural strategy promoting competitive tolerance and coexistence.
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Affiliation(s)
- Pamela R Belter
- Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada T6G 2E9
| | - James F Cahill
- Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada T6G 2E9
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Wolf ID, Croft DB. Impacts of tourism hotspots on vegetation communities show a higher potential for self-propagation along roads than hiking trails. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2014; 143:173-185. [PMID: 24907669 DOI: 10.1016/j.jenvman.2014.04.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Revised: 01/25/2014] [Accepted: 04/13/2014] [Indexed: 06/03/2023]
Abstract
Vegetation communities along recreational tracks may suffer from substantial edge-effects through the impacts of trampling, modified environmental conditions and competition with species that benefit from disturbance. We assessed impacts on trackside vegetation by comparing high and low usage tourism sites at a 1-10 m distance from recreational tracks in a popular arid-lands tourism destination in South Australia. The central aim was quantification of the strengths and spatial extent of tourism impacts along recreational tracks with a qualitative comparison of roads and trails. Track-distance gradients were most prevalent at high usage sites. There, species community composition was altered, total plant cover decreased, non-native species cover increased, plant diversity increased or decreased (depending on the distance) and soil compaction increased towards recreational tracks. Roadside effects were greater and more pervasive than trailside effects. Further, plant diversity did not continuously increase towards the road verge as it did along trails but dropped sharply in the immediate road shoulder which indicated high disturbance conditions that few species were able to tolerate. To our knowledge, we are the first to demonstrate that the access mode to a recreation site influences the potential of certain impacts, such as the increase of non-native species, to self-perpetuate from their points of introduction to disjointed sites with a predisposition to disturbance. Due to this propulsion of impacts, the overall spatial extent of roadside impacts was far greater than initially apparent from assessments at the road verge. We discuss possible means of mitigating these impacts.
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Affiliation(s)
- Isabelle D Wolf
- Centre for Ecosystem Science, University of New South Wales, Sydney, NSW 2052, Australia.
| | - David B Croft
- School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, NSW 2052, Australia.
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Greene B, Blossey B. Patterns of Privet: Urbanizing Watersheds, Invasive Ligustrum sinense, and Performance of Native Plant Species in Piedmont Floodplain Forests. Ecosystems 2014. [DOI: 10.1007/s10021-014-9774-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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9
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Miller AL, Diez JM, Sullivan JJ, Wangen SR, Wiser SK, Meffin R, Duncan RP. Quantifying invasion resistance: the use of recruitment functions to control for propagule pressure. Ecology 2014; 95:920-9. [DOI: 10.1890/13-0655.1] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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10
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Holeski LM, Keefover-Ring K, Bowers MD, Harnenz ZT, Lindroth RL. Patterns of Phytochemical Variation in Mimulus guttatus (Yellow Monkeyflower). J Chem Ecol 2013; 39:525-36. [DOI: 10.1007/s10886-013-0270-7] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Revised: 12/19/2012] [Accepted: 02/18/2013] [Indexed: 11/29/2022]
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Nilsson C, Brown RL, Jansson R, Merritt DM. The role of hydrochory in structuring riparian and wetland vegetation. Biol Rev Camb Philos Soc 2011; 85:837-58. [PMID: 20233190 DOI: 10.1111/j.1469-185x.2010.00129.x] [Citation(s) in RCA: 149] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Hydrochory, or the passive dispersal of organisms by water, is an important means of propagule transport, especially for plants. During recent years, knowledge about hydrochory and its ecological consequences has increased considerably and a substantial body of literature has been produced. Here, we review this literature and define the state of the art of the discipline. A substantial proportion of species growing in or near water have propagules (fruits, seeds or vegetative units) able to disperse by water, either floating, submerged in flowing water, or with the help of floating vessels. Hydrochory can enable plants to colonize sites out of reach with other dispersal vectors, but the timing of dispersal and mechanisms of establishment are important for successful establishment. At the population level, hydrochory may increase the effective size and longevity of populations, and control their spatial configuration. Hydrochory is also an important source of species colonizing recruitment-limited riparian and wetland communities, contributing to maintenance of community species richness. Dispersal by water may even influence community composition in different landscape elements, resulting in landscape-level patterns. Genetically, hydrochory may reduce spatial aggregation of genetically related individuals, lead to high gene flow among populations, and increase genetic diversity in populations receiving many propagules. Humans have impacted hydrochory in many ways. For example, dams affect hydrochory by reducing peak flows and hence dispersal capacity, altering the timing of dispersal, and by presenting physical barriers to dispersal, with consequences for riverine plant communities. Hydrochory has been inferred to be an important vector for the spread of many invasive species, but there is also the potential for enhancing ecosystem restoration by improving or restoring water dispersal pathways. Climate change may alter the role of hydrochory by modifying the hydrology of water-bodies as well as conditions for propagule release and plant colonization.
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Affiliation(s)
- Christer Nilsson
- Landscape Ecology Group, Department of Ecology and Environmental Science, Umeå University, SE-901 87 Umeå, Sweden.
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Altieri AH, van Wesenbeeck BK, Bertness MD, Silliman BR. Facilitation cascade drives positive relationship between native biodiversity and invasion success. Ecology 2010; 91:1269-75. [PMID: 20503860 DOI: 10.1890/09-1301.1] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The pervasive impact of invasive species has motivated considerable research to understand how characteristics of invaded communities, such as native species diversity, affect the establishment of invasive species. Efforts to identify general mechanisms that limit invasion success, however, have been frustrated by disagreement between landscape-scale observations that generally find a positive relationship between native diversity and invasibility and smaller-scale experiments that consistently reveal competitive interactions that generate the opposite relationship. Here we experimentally elucidate the mechanism explaining the large-scale positive associations between invasion success and native intertidal diversity revealed in our landscape-scale surveys of New England shorelines. Experimental manipulations revealed this large-scale pattern is driven by a facilitation cascade where ecosystem-engineering species interact nonlinearly to enhance native diversity and invasion success by alleviating thermal stress and substrate instability. Our findings reveal that large-scale diversity-invasion relationships can be explained by small-scale positive interactions that commonly occur across multiple trophic levels and functional groups. We argue that facilitation has played an important but unrecognized role in the invasion of other well studied systems, and will be of increasing importance with anticipated climate change.
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Affiliation(s)
- Andrew H Altieri
- Department of Ecology and Evolutionary Biology, Brown University, Providence, Rhode Island 02912, USA.
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14
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Minor ES, Tessel SM, Engelhardt KAM, Lookingbill TR. The role of landscape connectivity in assembling exotic plant communities: a network analysis. Ecology 2009; 90:1802-9. [DOI: 10.1890/08-1015.1] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Abstract
Adaptive divergence due to habitat differences is thought to play a major role in formation of new species. However it is rarely clear the extent to which individual reproductive isolating barriers related to habitat differentiation contribute to total isolation. Furthermore, it is often difficult to determine the specific environmental variables that drive the evolution of those ecological barriers, and the geographic scale at which habitat-mediated speciation occurs. Here, we address these questions through an analysis of the population structure and reproductive isolation between coastal perennial and inland annual forms of the yellow monkeyflower, Mimulus guttatus. We found substantial morphological and molecular genetic divergence among populations derived from coast and inland habitats. Reciprocal transplant experiments revealed nearly complete reproductive isolation between coast and inland populations mediated by selection against immigrants and flowering time differences, but not postzygotic isolation. Our results suggest that selection against immigrants is a function of adaptations to seasonal drought in inland habitat and to year round soil moisture and salt spray in coastal habitat. We conclude that the coast and inland populations collectively comprise distinct ecological races. Overall, this study suggests that adaptations to widespread habitats can lead to the formation of reproductively isolated species.
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Affiliation(s)
- David B Lowry
- University Program in Genetics and Genomics, Duke University Medical Center, Box 3565, and Department of Biology, Box 90338, Duke University Medical Center, Durham, North Carolina 27710, USA.
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Srivastava DS, Kolasa J, Bengtsson J, Gonzalez A, Lawler SP, Miller TE, Munguia P, Romanuk T, Schneider DC, Trzcinski MK. Are natural microcosms useful model systems for ecology? Trends Ecol Evol 2007; 19:379-84. [PMID: 16701289 DOI: 10.1016/j.tree.2004.04.010] [Citation(s) in RCA: 177] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Several recent, high-impact ecological studies feature natural microcosms as tools for testing effects of fragmentation, metacommunity theory or links between biodiversity and ecosystem processes. These studies combine the microcosm advantages of small size, short generation times, contained structure and hierarchical spatial arrangement with advantages of field studies: natural environmental variance, 'openness' and realistic species combinations with shared evolutionary histories. This enables tests of theory pertaining to spatial and temporal dynamics, for example, the effects of neighboring communities on local diversity, or the effects of biodiversity on ecosystem function. Using examples, we comment on the position of natural microcosms in the roster of ecological research strategies and tools. We conclude that natural microcosms are as versatile as artificial microcosms, but as complex and biologically realistic as other natural systems. Research to date combined with inherent attributes of natural microcosms make them strong candidate model systems for ecology.
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Affiliation(s)
- Diane S Srivastava
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, 6270 University Blvd, Vancouver, BC, Canada, V6T 1Z4.
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Sousa WP, Kennedy PG, Mitchell BJ, Ordóñez L BM. SUPPLY-SIDE ECOLOGY IN MANGROVES: DO PROPAGULE DISPERSAL AND SEEDLING ESTABLISHMENT EXPLAIN FOREST STRUCTURE? ECOL MONOGR 2007. [DOI: 10.1890/05-1935] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Abstract
The importance of facilitation to local community dynamics is becoming increasingly recognized. However, the predictability of positive interactions in stressful environments, the balance of competition and facilitation along environmental gradients, and the scaling of local positive interactions to regional distributions are aspects of facilitation that remain unresolved. I explored these questions in a habitat specialist, Delphinium uliginosum, and a moss, Didymodon tophaceus, both found in small serpentine wetlands. I tested three hypotheses: (1) moss facilitates germination, growth, and/or fecundity of D. uliginosum; (2) facilitation is stronger at the harsher ends of gradients in soil moisture, toxicity, and/or biomass; and (3) facilitation is reflected in positive associations at the levels of local abundance and regional occurrence. Although considerable competitive interactions occurred in later life stages, moss strongly facilitated D. uliginosum seedling emergence. There was no evidence that this facilitative effect weakened, or switched to competition, in benign environments. D. uliginosum was more locally abundant and more frequently present, across a large portion of its range, with than without moss, indicating a net facilitative effect in the face of competitive influences. Facilitated recruitment, possibly by seed retention, was found to be an important control on abundance and distribution in this rare species.
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Affiliation(s)
- Amy L Freestone
- Environmental Science and Policy, University of California, Davis, California 95616, USA.
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R. Houseman G, L. Gross K. Does ecological filtering across a productivity gradient explain variation in species pool-richness relationships? OIKOS 2006. [DOI: 10.1111/j.2006.0030-1299.14743.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Lambrinos JG. Spatially variable propagule pressure and herbivory influence invasion of chaparral shrubland by an exotic grass. Oecologia 2005; 147:327-34. [PMID: 16189663 DOI: 10.1007/s00442-005-0259-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2005] [Accepted: 08/25/2005] [Indexed: 10/25/2022]
Abstract
Although numerous studies have identified mechanisms that either resist or facilitate biological invasions, few studies have explicitly tested how resisting and facilitating mechanisms interact to drive invasion success. In California, USA, undisturbed Mediterranean-type shrublands have resisted invasion by the perennial tussock grass Cortaderia jubata. In some cases, however, this resistance has been spectacularly breached even in the absence of large-scale disturbance. I tested the hypothesis that these invasions are facilitated by local reductions in the strength of biotic resistance. I evaluated invasive success using C. jubata seed and seedling additions at different microhabitats: the edge of a chaparral stand, under shrub canopy at different distances from the stand edge, and in canopy gaps within the stand. When left exposed to mammalian herbivores, seedling survivorship decreased sharply from nearly 40% on the stand edge to zero just 10 m into the stand. When transplants were protected from herbivory, however, distance from the edge had no significant influence on transplant survivorship. Seedling emergence was also greater on the edge and in canopy gaps than under the canopy, but these differences were not caused by differences in herbivory. The flux of invasive propagules reaching the soil surface was immense and greater along the edge and within gaps than under the stand canopy. Mirroring these patterns, naturally occurring seedling abundance declined dramatically with distance from the stand edge, and seedlings were far more common within stand gaps than would be expected given gap frequency within the stand. Despite strong biotic resistance to invasion within the stand, the cover of C. jubata has increased 20% over the last 9 years. These results suggest that the relative amount of susceptible edge habitat and the supply of invasive propagules can facilitate invasion even in the face of strong local biotic resistance.
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Affiliation(s)
- John G Lambrinos
- Department of Environmental Science and Policy, University of California, One Shields Ave., Davis, CA 95616, USA.
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Gilbert B, Lechowicz MJ. INVASIBILITY AND ABIOTIC GRADIENTS: THE POSITIVE CORRELATION BETWEEN NATIVE AND EXOTIC PLANT DIVERSITY. Ecology 2005. [DOI: 10.1890/04-09997] [Citation(s) in RCA: 154] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Rudgers JA, Mattingly WB, Koslow JM. Mutualistic fungus promotes plant invasion into diverse communities. Oecologia 2005; 144:463-71. [PMID: 15942761 DOI: 10.1007/s00442-005-0039-y] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2004] [Accepted: 02/01/2005] [Indexed: 10/25/2022]
Abstract
Reducing the biological diversity of a community may decrease its resistance to invasion by exotic species. Manipulative experiments typically support this hypothesis but have focused mainly on one trophic level (i.e., primary producers). To date, we know little about how positive interactions among species may influence the relationship between diversity and invasibility, which suggests a need for research that addresses the question: under what conditions does diversity affect resistance to invasion? We used experimental manipulations of both plant diversity and the presence of an endophytic fungus to test whether a fungal mutualist of an invasive grass species (Lolium arundinaceum) switches the relationship between plant community diversity and resistance to invasion. Association with the fungal endophyte (Neotyphodium coenophialum) increased the ability of L. arundinaceum to invade communities with greater species diversity. In the absence of the endophyte, the initial diversity of the community significantly reduced the establishment of L. arundinaceum. However, establishment was independent of initial diversity in the presence of the endophyte. Fungal symbionts, like other key species, are often overlooked in studies of plant diversity, yet their presence may explain variation among studies in the effect of diversity on resistance to invasion.
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Jiang L, Morin PJ. Productivity gradients cause positive diversity-invasibility relationships in microbial communities. Ecol Lett 2004. [DOI: 10.1111/j.1461-0248.2004.00660.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Williams JL, Levine JM. Small-scale variation in growing season length affects size structure of scarlet monkeyflower. OIKOS 2004. [DOI: 10.1111/j.0030-1299.2004.13040.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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28
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Wolters M, Geertsema J, Chang ER, Veeneklaas RM, Carey PD, Bakker JP. Astroturf seed traps for studying hydrochory. Funct Ecol 2004. [DOI: 10.1111/j.1365-2435.2004.00813.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Levine JM, Murrell DJ. The Community-Level Consequences of Seed Dispersal Patterns. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2003. [DOI: 10.1146/annurev.ecolsys.34.011802.132400] [Citation(s) in RCA: 329] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Jonathan M. Levine
- Department of Ecology, Evolution, and Marine Biology, University of California, Santa Barbara, California 93106;
- Center for Population Biology, Imperial College at Silwood Park, Ascot, Berkshire SL5 7PY, United Kingdom;
| | - David J. Murrell
- Department of Ecology, Evolution, and Marine Biology, University of California, Santa Barbara, California 93106;
- Center for Population Biology, Imperial College at Silwood Park, Ascot, Berkshire SL5 7PY, United Kingdom;
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Collins SL, Glenn SM, Briggs JM. Effect of local and regional processes on plant species richness in tallgrass prairie. OIKOS 2003. [DOI: 10.1034/j.1600-0706.2002.12112.x] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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