1
|
Rohal CB, Duncan B, Follstad Shah J, Veblen KE, Kettenring KM. Targeted grazing reduces a widespread wetland plant invader with minimal nutrient impacts, yet native community recovery is limited. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 362:121168. [PMID: 38823302 DOI: 10.1016/j.jenvman.2024.121168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 05/06/2024] [Accepted: 05/10/2024] [Indexed: 06/03/2024]
Abstract
Targeted grazing to control undesirable plant species is increasingly of interest across a diversity of ecosystems, particularly as an alternative or complement to widely used herbicides. However, there are limited comprehensive evaluations of targeted grazing that evaluate both invasive species management effectiveness and potential negative effects on the ecosystem. Phragmites australis, a tall-statured, dense perennial invasive grass from Eurasia, is a pervasive problem in wetlands across the North American continent. As with many invasive species where management has historically relied on herbicides and resistance is a growing concern, land managers seek viable alternatives that have minimal negative ecosystem impacts. Grazing has been used for millennia to manage native Phragmites in Europe. Similarly, in its invasive range within North America, small-scale studies suggest Phragmites may be suppressed by grazers. Yet, the effectiveness of grazing at large scales and its effects on broader ecosystem properties remain largely unknown. We evaluated the influence of targeted grazing on vegetation, soil nutrients, and water nutrients over two years in large plots (∼300x the size of previous studies). We also tested the effects of mowing, a treatment that can be used to facilitate grazer access to large, dense Phragmites stands. In line with our predictions, we found that cattle grazing effectively suppressed invasive Phragmites over two years. Mowing reduced litter, and moderately reduced standing dead Phragmites, both of which suppress native plant germination in this system. However, these reductions in Phragmites were not accompanied by indications of native plant community recovery, as we had optimistically predicted. Despite the potential for grazing to reduce nutrient sequestration by plants and fertilize soils, we were surprised to find no clear negative effects of grazing on nutrient mobilization to groundwater or floodwater. Taken together, our findings indicate that targeted grazing, when implemented at broad scales over short time frames, is effective at achieving invasive plant management goals without sizable nutrient impacts. However, additional steps will be needed to achieve the restoration of diverse, robust native plant communities.
Collapse
Affiliation(s)
- Christine B Rohal
- Department of Environmental Horticulture and Soil, Water, and Ecosystem Sciences Department, University of Florida, Gainesville, FL, 32611, USA; Department of Watershed Sciences and Ecology Center, Utah State University, Logan, UT, 84322, USA.
| | - Brittany Duncan
- Department of Watershed Sciences and Ecology Center, Utah State University, Logan, UT, 84322, USA; Utah Department of Agriculture and Food, Taylorsville, UT, 84129, USA
| | - Jennifer Follstad Shah
- School of the Environment, Society & Sustainability, University of Utah, Salt Lake City, UT, 84112, USA
| | - Kari E Veblen
- Department of Wildland Resources and Ecology Center, Utah State University, Logan, UT, 84322, USA
| | - Karin M Kettenring
- Department of Watershed Sciences and Ecology Center, Utah State University, Logan, UT, 84322, USA
| |
Collapse
|
2
|
Ellis KS, Larsen RT, Koons DN. Dependence of spatial scale in landscape associations with cause‐specific predation of snowy plover nests. Ecosphere 2020. [DOI: 10.1002/ecs2.3257] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Affiliation(s)
- Kristen S. Ellis
- Department of Fish, Wildlife, and Conservation Biology Colorado State University Fort Collins Colorado80523USA
| | - Randy T. Larsen
- Department of Plant and Wildlife Sciences Brigham Young University Provo Utah84602USA
| | - David N. Koons
- Department of Fish, Wildlife, and Conservation Biology, and Graduate Degree Program in Ecology Colorado State University Fort Collins Colorado80523USA
| |
Collapse
|
3
|
Ellis KS, Larsen RT, Koons DN. The importance of functional responses among competing predators for avian nesting success. Funct Ecol 2019. [DOI: 10.1111/1365-2435.13460] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Kristen S. Ellis
- Department of Fish, Wildlife, and Conservation Biology Colorado State University Fort Collins CO USA
| | - Randy T. Larsen
- Department of Plant and Wildlife Sciences Brigham Young University Provo UT USA
| | - David N. Koons
- Department of Fish, Wildlife, and Conservation Biology Graduate Degree Program in Ecology Colorado State University Fort Collins CO USA
| |
Collapse
|
4
|
Evidence does not support the targeting of cryptic invaders at the subspecies level using classical biological control: the example of Phragmites. Biol Invasions 2019. [DOI: 10.1007/s10530-019-02014-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
|
5
|
Williams J, Lambert AM, Long R, Saltonstall K. Does hybrid Phragmites australis differ from native and introduced lineages in reproductive, genetic, and morphological traits? AMERICAN JOURNAL OF BOTANY 2019; 106:29-41. [PMID: 30633812 DOI: 10.1002/ajb2.1217] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 10/03/2018] [Indexed: 06/09/2023]
Abstract
PREMISE OF THE STUDY Hybridization between previously isolated species or lineages can stimulate invasiveness because of increased genetic diversity and inherited traits facilitating competitive and reproductive potential. We evaluated differences in stand characteristics and sexual and vegetative reproduction among native, introduced, and hybrid Phragmites australis lineages in the southwestern United States. We also assessed the degree of hybridization among lineages and backcrossing of hybrids with parental lineages. METHODS Growth and morphological characteristics were measured in native, introduced, and hybrid Phragmites stands to evaluate relative cover and dominance in associated plant communities. Panicles were collected from stands to evaluate germination, dormancy, and differences in seed traits. Seedlings from germination trials were genotyped to determine frequency of crossing and backcrossing among lineages. KEY RESULTS Introduced and hybrid Phragmites stands had significantly greater stem and panicle densities than native stands and were more likely to be dominant members of their respective plant communities. Hybrid seed outputs were significantly greater, but hybrid seeds had lower germination rates than those from native and introduced lineages. We detected a novel hybridization event between native and introduced lineages, but found no strong evidence of hybrids backcrossing with parental lineages. CONCLUSIONS Hybrid Phragmites in the Southwest exhibits reproductive, genetic, and morphological characteristics from both parental lineages that facilitate dispersal, establishment, and aggressive growth, including high reproductive output, rhizome viability, and aboveground biomass, with smaller seeds and greater genetic diversity than its progenitors. Our results show hybrids can inherit traits that confer invasiveness and provide insight for managing this species complex and other cryptic species with native and introduced variants with potential for intraspecific hybridization.
Collapse
Affiliation(s)
- Jared Williams
- Marine Science Institute and Cheadle Center for Biodiversity and Ecological Restoration, University of California, Santa Barbara, CA, 93106-6150, USA
| | - Adam M Lambert
- Marine Science Institute and Cheadle Center for Biodiversity and Ecological Restoration, University of California, Santa Barbara, CA, 93106-6150, USA
| | - Randy Long
- Ecology, Evolution, and Marine Biology, University of California, Santa Barbara, CA, 93106, USA
| | - Kristin Saltonstall
- Smithsonian Tropical Research Institute, Apartado, 0843-03092, Balboa, Ancon, Republic of Panama
| |
Collapse
|
6
|
Guo WY, Lambertini C, Pyšek P, Meyerson LA, Brix H. Living in two worlds: Evolutionary mechanisms act differently in the native and introduced ranges of an invasive plant. Ecol Evol 2018. [PMID: 29531666 PMCID: PMC5838077 DOI: 10.1002/ece3.3869] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Identifying the factors that influence spatial genetic structure among populations can provide insights into the evolution of invasive plants. In this study, we used the common reed (Phragmites australis), a grass native in Europe and invading North America, to examine the relative importance of geographic, environmental (represented by climate here), and human effects on population genetic structure and its changes during invasion. We collected samples of P. australis from both the invaded North American and native European ranges and used molecular markers to investigate the population genetic structure within and between ranges. We used path analysis to identify the contributions of each of the three factors-geographic, environmental, and human-related-to the formation of spatial genetic patterns. Genetic differentiation was observed between the introduced and native populations, and their genetic structure in the native and introduced ranges was different. There were strong effects of geography and environment on the genetic structure of populations in the native range, but the human-related factors manifested through colonization of anthropogenic habitats in the introduced range counteracted the effects of environment. The between-range genetic differences among populations were mainly explained by the heterogeneous environment between the ranges, with the coefficient 2.6 times higher for the environment than that explained by the geographic distance. Human activities were the primary contributor to the genetic structure of the introduced populations. The significant environmental divergence between ranges and the strong contribution of human activities to the genetic structure in the introduced range suggest that invasive populations of P. australis have evolved to adapt to a different climate and to human-made habitats in North America.
Collapse
Affiliation(s)
- Wen-Yong Guo
- Department of Invasion EcologyInstitute of Botany The Czech Academy of Sciences Průhonice Czech Republic.,Department of Bioscience Aarhus University Aarhus C Denmark
| | - Carla Lambertini
- Department of Bioscience Aarhus University Aarhus C Denmark.,Department of Agricultural Science University of Bologna Bologna Italy
| | - Petr Pyšek
- Department of Invasion EcologyInstitute of Botany The Czech Academy of Sciences Průhonice Czech Republic.,Department of Ecology Faculty of Science Charles University Prague Czech Republic
| | - Laura A Meyerson
- Natural Resources Science The University of Rhode Island Kingston RI USA
| | - Hans Brix
- Department of Bioscience Aarhus University Aarhus C Denmark
| |
Collapse
|
7
|
Rohal CB, Kettenring KM, Sims K, Hazelton ELG, Ma Z. Surveying managers to inform a regionally relevant invasive Phragmites australis control research program. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2018; 206:807-816. [PMID: 29182931 DOI: 10.1016/j.jenvman.2017.10.049] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 08/21/2017] [Accepted: 10/23/2017] [Indexed: 06/07/2023]
Abstract
Managers of invasive species consider the peer-reviewed literature only moderately helpful for guiding their management programs. Though this "knowing-doing gap" has been well-described, there have been few efforts to guide scientists in how to develop useful and usable science. Here we demonstrate how a comprehensive survey of managers (representing 42 wetland management units across the Great Salt Lake watershed) can highlight management practices and challenges (here for the widespread invasive plant, Phragmites australis, a recent and aggressive invader in this region) to ultimately inform a research program. The diversity of surveyed organizations had wide-ranging amounts of Phragmites which led to different goals and approaches including more aggressive control targets and a wider array of control tools for smaller, private organizations compared to larger government-run properties. We found that nearly all managers (97%) used herbicide as their primary Phragmites control tool, while burning (65%), livestock grazing (49%), and mowing (43%) were also frequently used. Managers expressed uncertainties regarding the timing of herbicide application and type of herbicide for effective control. Trade-offs between different Phragmites treatments were driven by budgetary concerns, as well as environmental conditions like water levels and social constraints like permitting issues. Managers had specific ideas about the plant communities they desired following Phragmites control, yet revegetation of native species was rarely attempted. The results of this survey informed the development of large-scale, multi-year Phragmites control and native plant revegetation experiments to address management uncertainties regarding herbicide type and timing. The survey also facilitated initial scientist-manager communication, which led to collaborations and knowledge co-production between managers and researchers. An important outcome of the survey was that experimental results were more pertinent to manager needs and trusted by managers. Such an approach that integrates manager surveys to inform management experiments could be adapted to any developing research program seeking to be relevant to management audiences.
Collapse
Affiliation(s)
- C B Rohal
- Department of Watershed Sciences and Ecology Center, Utah State University, United States.
| | - K M Kettenring
- Department of Watershed Sciences and Ecology Center, Utah State University, United States
| | - K Sims
- Department of Economics, University of Tennessee, United States
| | - E L G Hazelton
- Department of Watershed Sciences and Ecology Center, Utah State University, United States
| | - Z Ma
- Department of Forestry and Natural Resources, Purdue University, United States
| |
Collapse
|
8
|
Uddin MN, Robinson RW. Allelopathy and resource competition: the effects of Phragmites australis invasion in plant communities. BOTANICAL STUDIES 2017; 58:29. [PMID: 28664396 PMCID: PMC5491426 DOI: 10.1186/s40529-017-0183-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Accepted: 06/16/2017] [Indexed: 05/29/2023]
Abstract
BACKGROUND Phragmites australis, a ubiquitous wetland plant, has been considered one of the most invasive species in the world. Allelopathy appears to be one of the invasion mechanisms, however, the effects could be masked by resource competition among target plants. The difficulty of distinguishing allelopathy from resource competition among plants has hindered investigations of the role of phytotoxic allelochemicals in plant communities. This has been addressed via experiments conducted in both the greenhouse and laboratory by growing associated plants, Melaleuca ericifolia, Rumex conglomeratus, and model plant, Lactuca sativa at varying densities with the allelopathic plant, P. australis, its litter and leachate of P. australis litter. This study investigated the potential interacting influences of allelopathy and resource competition on plant growth-density relationships. RESULTS In greenhouse, the root exudates mediated effects showed the strongest growth inhibition of M. ericifolia at high density whereas litter mediated results revealed increased growth at medium density treatments compared to low and high density. Again, laboratory experiments related to seed germination and seedling growth of L. sativa and R. conglomeratus exhibited phytotoxicity decreased showing positive growth as plant density increased and vice versa. Overall, the differential effects were observed among experiments but maximum individual plant biomass and some other positive effects on plant traits such as root and shoot length, chlorophyll content occurred at an intermediate density. This was attributed to the sharing of the available phytotoxin among plants at high densities which is compatible to density-dependent phytotoxicity model. CONCLUSIONS The results demonstrated that plant-plant interference is the combined effect of allelopathy and resource competition with many other factors but this experimental design, target-neighbor mixed-culture in combination of plant grown at varying densities with varying level of phytotoxins, mono-culture, can successfully separate allelopathic effects from competition.
Collapse
Affiliation(s)
- Md Nazim Uddin
- Department of Ecology & Environmental Management, College of Engineering & Science, Victoria University, Melbourne, VIC 8001 Australia
- Institute for Sustainability & Innovation, Victoria University, Melbourne, VIC 8001 Australia
| | - Randall William Robinson
- Department of Ecology & Environmental Management, College of Engineering & Science, Victoria University, Melbourne, VIC 8001 Australia
- Institute for Sustainability & Innovation, Victoria University, Melbourne, VIC 8001 Australia
| |
Collapse
|
9
|
Management of invasive Phragmites australis in the Adirondacks: a cautionary tale about prospects of eradication. Biol Invasions 2017. [DOI: 10.1007/s10530-017-1513-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
|
10
|
Duncan JP, Rozum RN, Powell JA, Kettenring KM. Multi-scale methods predict invasion speeds in variable landscapes. THEOR ECOL-NETH 2017. [DOI: 10.1007/s12080-017-0329-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
11
|
Bohórquez E, Paredes D, Arias CA. Vertical flow-constructed wetlands for domestic wastewater treatment under tropical conditions: effect of different design and operational parameters. ENVIRONMENTAL TECHNOLOGY 2017; 38:199-208. [PMID: 27628332 DOI: 10.1080/09593330.2016.1230650] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
This study assessed the treatment of domestic wastewater to find the optimum vertical flow-constructed wetland (VFCW) configuration under tropical conditions. Eight pilot-scale configurations units were studied to compare between fine sand and medium gravel used as substrate, two feeding frequencies (20 pulses d-1 and 10 pulses d-1), and the presence or absence of tropical plants (Heliconia psittacorum). The results showed that the sand beds were significantly more efficient in the removal of organic matter, ammonia nitrogen, and total suspended solids than gravel beds, presenting average removal rates of 48 and 24 g m-2 d-1 of COD; 35 and 16 g m-2 d-1 of BOD5; 7 and 4 g m-2 d-1 of [Formula: see text]; 9 and 0 g m-2 d-1 for sand and gravel, respectively. The oxygen consumption rates were calculated and a value of 65 g m-2 d-1 was obtained for sand beds while for the gravel beds the consumption rate was 30 g m-2 d-1. The assessment of different kinds of nitrogen showed interesting dynamics in the nitrification processes. The presence of H. psittacorum showed positive effects in the total nitrogen (TN) removal. The different loading frequencies applied did not show significant statistical differences in the removal of the tested contaminants. Preliminary results were found in the pathogen removal, where the sand is favorable as the substrate. This work represents the first step in the research of optimum VFWC design and operation parameters for Colombia as well as the use of plants of the genus Heliconia.
Collapse
Affiliation(s)
- Eliana Bohórquez
- a Water and Sanitation Research Group, Faculty of Environmental Sciences , Universidad Tecnológica de Pereira , Pereira , Colombia
| | - Diego Paredes
- a Water and Sanitation Research Group, Faculty of Environmental Sciences , Universidad Tecnológica de Pereira , Pereira , Colombia
| | | |
Collapse
|
12
|
|
13
|
Saltonstall K, Lambert AM, Rice N. What happens in Vegas, better stay in Vegas: Phragmites australis hybrids in the Las Vegas Wash. Biol Invasions 2016. [DOI: 10.1007/s10530-016-1167-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023]
|
14
|
Life on the edge: reproductive mode and rate of invasive Phragmites australis patch expansion. Biol Invasions 2016. [DOI: 10.1007/s10530-016-1125-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|
15
|
Multitrophic enemy escape of invasive Phragmites australis and its introduced herbivores in North America. Biol Invasions 2015. [DOI: 10.1007/s10530-015-0968-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
16
|
Cronin JT, Bhattarai GP, Allen WJ, Meyerson LA. Biogeography of a plant invasion: plant–herbivore interactions. Ecology 2015; 96:1115-27. [DOI: 10.1890/14-1091.1] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
|
17
|
Piwpuan N, Jampeetong A, Brix H. Ammonium tolerance and toxicity of Actinoscirpus grossus--a candidate species for use in tropical constructed wetland systems. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2014; 107:319-328. [PMID: 25038560 DOI: 10.1016/j.ecoenv.2014.05.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2013] [Revised: 05/29/2014] [Accepted: 05/29/2014] [Indexed: 06/03/2023]
Abstract
Actinoscirpus grossus, a native species in tropical wetlands of South-East Asia, North Australia and the Pacific islands, has been reported to perform well in experimental scale constructed wetland (CW) systems. However, little is known about how high NH4(+) concentrations prevailing in wastewater affect growth and performance of this species. We examined growth, morphological and physiological responses of A. grossus to NH4(+) concentrations of 0.5, 2.5, 5, 10 and 15mM under hydroponic growth conditions. The relative growth rates (RGR) of the plants were highest at 2.5mM NH4(+) but significantly reduced at 10 and 15mM NH4(+). The roots of the plants were stunted and produced subepidermal lignified-cell layers at exposure to 10 and 15mM NH4(+). The photosynthetic rates did not differ between treatments (average An=21.3±0.4µmolCO2m(-2)s(-1)) but the photosynthetic nitrogen and carbon use efficiency (PNUE and PCUE) were significantly depressed at 10 and 15mM NH4(+) treatments. The concentration of NH4(+) in the roots, but not in the leaves, reflected the NH4(+) concentration in the growth medium suggesting that the species is unable to regulate the NH4(+) uptake. The high root respiration rates in concert with high tissue NH4(+) and declined C/N ratio at 10 and 15mM NH4(+) suggest that the NH4(+) assimilation occurs primarily in the roots and the plant has inadequate C-skeletons for NH4(+) assimilation and exudation at high NH4(+) concentration in the external solution. The concentrations of mineral cations were generally reduced and the root membrane permeability increased at high external NH4(+) concentrations. Our study shows that A. grossus tolerates NH4(+) concentrations up to 5mM which is characteristic of most types of wastewater. Hence, A. grossus is a good native candidate species for use in CW systems in tropical and subtropical climates in South-East Asia, North Australia and the Pacific islands.
Collapse
Affiliation(s)
- Narumol Piwpuan
- Faculty of Science and Technology, Aarhus University, Ole Worms Allé 1, 8000 Aarhus C, Denmark.
| | - Arunothai Jampeetong
- Department of Biology, Faculty of Science, Chiang Mai University, Meuang, Chiang Mai 50202, Thailand
| | - Hans Brix
- Faculty of Science and Technology, Aarhus University, Ole Worms Allé 1, 8000 Aarhus C, Denmark
| |
Collapse
|
18
|
Vanderlinder MS, Neale CMU, Rosenberg DE, Kettenring KM. Use of Remote Sensing to Assess Changes in Wetland Plant Communities Over An 18-Year Period: A Case Study from the Bear River Migratory Bird Refuge, Great Salt Lake, Utah. WEST N AM NATURALIST 2014. [DOI: 10.3398/064.074.0104] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
19
|
Uddin MN, Robinson RW, Caridi D, Al Harun MAY. Suppression of native Melaleuca ericifolia by the invasive Phragmites australis through allelopathic root exudates. AMERICAN JOURNAL OF BOTANY 2014; 101:479-87. [PMID: 24634438 DOI: 10.3732/ajb.1400021] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
PREMISE OF THE STUDY Invasive plants are a great threat to the conservation of natural ecosystems and biodiversity. Allelopathy as a mechanism for invasion of plants such as Phragmites australis, one of the most aggressive invaders, has the potential to suppress neighboring plant species. Allelopathic interference, through root exudates of P. australis on native Melaleuca ericifolia, was investigated to find out the underlying invasion mechanisms. METHODS Germination and growth effects of P. australis on M. ericifolia were studied in the greenhouse using potting mix both with and without activated carbon, and a combination of single and repeated cuttings of P. australis as the management tool. KEY RESULTS P. AUSTRALIS had significant negative effects on germination and growth of M. ericifolia by inhibiting germination percentage, maximum root length and plant height, biomass, stem diameter, and number of growth points with little effect on leaf physiology. Activated carbon (AC) in turn moderately counteracted these effects. The cutting of P. australis shoots significantly reduced the suppressive effects on M. ericifolia compared to the addition of AC to soil. Furthermore, significant changes in soil such as pH, electrical conductivity, osmotic potential, phenolics, and dehydrogenase activity were identified among cutting treatments with little variation between AC treatments. CONCLUSION The results demonstrated that allelopathy through root exudates of P. australis had relatively low contribution in suppressing M. ericifolia in comparison to other competitive effects. Management tools combining repeated cutting of P. australis shoots with AC treatments may assist partly in the restoration of native ecosystems invaded by P. australis.
Collapse
Affiliation(s)
- Md Nazim Uddin
- College of Engineering & Science, Victoria University, St. Albans Campus, Melbourne, Victoria 8001, Australia
| | | | | | | |
Collapse
|
20
|
Impacts of plant invasions can be reversed through restoration: a regional meta-analysis of faunal communities. Biol Invasions 2013. [DOI: 10.1007/s10530-012-0404-9] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
21
|
Kettenring KM, de Blois S, Hauber DP. Moving from a regional to a continental perspective of Phragmites australis invasion in North America. AOB PLANTS 2012; 2012:pls040. [PMID: 23755351 PMCID: PMC3676263 DOI: 10.1093/aobpla/pls040] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2012] [Accepted: 10/17/2012] [Indexed: 05/25/2023]
Abstract
AIMS We use a regional comparison of Phragmites australis (common reed) subsp. americanus, P. australis subsp. berlandieri and introduced P. australis (possibly five sublineages) in the Chesapeake Bay, the St Lawrence River, Utah and the Gulf Coast to inform a North American perspective on P. australis invasion patterns, drivers, impacts and research needs. FINDINGS AND RESEARCH NEEDS: Our regional assessments reveal substantial diversity within and between the three main lineages of P. australis in terms of mode of reproduction and the types of environment occupied. For introduced P. australis, the timing of introduction also differed between the regions. Nevertheless, a common finding in these regions reinforces the notion that introduced P. australis is opportunistic and thrives in disturbed habitats. Thus, we expect to see substantial expansion of introduced P. australis with increasing anthropogenic disturbances in each of these regions. Although there have been some studies documenting the negative impacts of introduced P. australis, it also plays a beneficial role in some regions, and in some cases, the purported negative impacts are unproven. There is also a broader need to clarify the genetic and ecological relationships between the different introduced sublineages observed in North America, and their relative competitive ability and potential for admixture. This may be done through regional studies that use similar methodologies and share results to uncover common patterns and processes. To our knowledge, such studies have not been performed on P. australis in spite of the broad attention given to this species. Such research could advance theoretical knowledge on biological invasion by helping to determine the extent to which the patterns observed can be generalized or are sublineage specific or region specific. SYNTHESIS Given what appears to be sometimes idiosyncratic invasion patterns when interpreted in isolation in the regions that we analysed, it may be time to consider initiatives on a continental (if not intercontinental) scale to tackle unresolved issues about P. australis.
Collapse
Affiliation(s)
- Karin M. Kettenring
- Department of Watershed Sciences and Ecology
Center, Utah State University, Logan, UT
84322, USA
| | - Sylvie de Blois
- McGill School of Environment and Department of Plant
Science, McGill University, 21 111
Lakeshore, Ste-Anne-de-Bellevue, QC H9X 3V9, Canada
| | - Donald P. Hauber
- Department of Biological Sciences,
Loyola University, New Orleans, LA
70118, USA
| |
Collapse
|
22
|
Genetic diversity, reproductive mode, and dispersal differ between the cryptic invader, Phragmites australis, and its native conspecific. Biol Invasions 2012. [DOI: 10.1007/s10530-012-0246-5] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
23
|
Lambertini C, Mendelssohn IA, Gustafsson MHG, Olesen B, Riis T, Sorrell BK, Brix H. Tracing the origin of Gulf Coast Phragmites (Poaceae): a story of long-distance dispersal and hybridization. AMERICAN JOURNAL OF BOTANY 2012; 99:538-51. [PMID: 22334449 DOI: 10.3732/ajb.1100396] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
PREMISE OF THE STUDY Long-distance dispersal can affect speciation processes in two opposing ways. Dispersal can promote geographic isolation or it can bring together geographically distant and distantly related genotypes, thus counteracting local differentiation. We used the Gulf Coast of North America (GC), a "hot spot" of reed diversity and evolutionary dynamics, as a model system to study the diversification processes within the invasive, cosmopolitan, polyploid grass Phragmites. METHODS Genetic diversity was studied using collections representing all species of the genus and from all continents (except Antarctica). A range of molecular markers, including chloroplast and nuclear sequences, microsatellites, and AFLPs, was analyzed to detect DNA variation from the population to the species level and to infer phylogenetic relationships across continents. KEY RESULTS An interspecific hybrid, Phragmites mauritianus × P. australis, and four P. australis cp-DNA haplotypes from Africa, Europe, and North America have been dispersed to the GC and interbreed with each other. CONCLUSIONS Long-distance dispersal and weak breeding barriers appear to be recurring phenomena, not only in the GC, but worldwide. We present data strongly suggesting that interspecific hybridization and introgression among different Phragmites species take place and appear to have contributed significantly to the diversification processes within the genus. Hence, the application of traditional species concepts within Phragmites might be inappropriate.
Collapse
Affiliation(s)
- Carla Lambertini
- Department of Bioscience, Plant Biology, Aarhus University, Ole Worms Allé 1, 8000 Aarhus C, Denmark.
| | | | | | | | | | | | | |
Collapse
|
24
|
Meyerson LA, Lambertini C, McCormick MK, Whigham DF. Hybridization of common reed in North America? The answer is blowing in the wind. AOB PLANTS 2012; 2012:pls022. [PMID: 22993684 PMCID: PMC3444738 DOI: 10.1093/aobpla/pls022] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Accepted: 07/26/2012] [Indexed: 05/22/2023]
Abstract
BACKGROUND AND AIMS We review evidence for hybridization of Phragmites australis in North America and the implications for the persistence of native P. australis ssp. americanus populations in North America. We also highlight the need for an updated classification system, which takes P. australis intraspecific variation and hybridization into account. METHODOLOGY We reviewed available published, in press and in preparation literature to assess the likelihood of hybridization and interbreeding in genotypes of P. australis present in North America. PRINCIPAL RESULTS Experimental results demonstrate that hybridization among introduced and native haplotypes is possible within the genus Phragmites, yet evidence that hybridization has occurred naturally is only starting to emerge. The lag in identifying hybridization in Phragmites in North America may be related to under-sampling in some parts of North America and to a lack of molecular tools that provide the capability to recognize hybrids. CONCLUSIONS Our understanding of the gene flow within and between species in the genus Phragmites is moving at a fast pace, especially on the east and Gulf coasts of North America. More attention should also be focused on the Great Lakes region, the southwestern and the west coast of the USA, where sympatry has created opportunities for hybridization. Where hybridizations have been detected, there are currently no published data on how hybridization affects plant vigour, morphology, invasiveness or conservation of the genetic integrity of the North American native subspecies. We conclude that the detection of more hybridization is highly likely and that there is a need to develop new markers for the different Phragmites species and lineages to fill current knowledge gaps. Finally, we suggest that the classification system for P. australis should be updated and published to help clarify the nomenclature.
Collapse
Affiliation(s)
- L. A. Meyerson
- Department of Invasion Ecology, Institute of Botany, Academy of Sciences of the Czech Republic, Průhonice CZ 252 43, Czech Republic
- Department of Natural Resources Science, University of Rhode Island, Kingston, RI 02881, USA
- Corresponding author's e-mail address:
| | - C. Lambertini
- Department of Biosciences, Aarhus University, Aarhus, Denmark
| | - M. K. McCormick
- Smithsonian Environmental Research Center, PO Box 28, Edgewater, MD 20137, USA
| | - D. F. Whigham
- Smithsonian Environmental Research Center, PO Box 28, Edgewater, MD 20137, USA
| |
Collapse
|