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Mayol E, Boada J, Pérez M, Sanmartí N, Minguito-Frutos M, Arthur R, Alcoverro T, Alonso D, Romero J. Understanding the depth limit of the seagrass Cymodocea nodosa as a critical transition: Field and modeling evidence. MARINE ENVIRONMENTAL RESEARCH 2022; 182:105765. [PMID: 36252284 DOI: 10.1016/j.marenvres.2022.105765] [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: 07/21/2022] [Revised: 09/30/2022] [Accepted: 09/30/2022] [Indexed: 06/16/2023]
Abstract
Changes in light and sediment conditions can sometimes trigger abrupt regime shifts in seagrass meadows resulting in dramatic and unexpected die-offs of seagrass. Light attenuates rapidly with depth, and in seagrass systems with non-linear behaviours, can serve as a sharp boundary beyond which the meadow transitions to bare sand. Determining system behaviour is therefore essential to ensuring resilience is maintained and to prevent stubborn critical ecosystem transitions caused by declines in water quality. Here we combined field and modelling studies to explore the transition from meadow to bare sand in the seagrass Cymodocea nodosa at the limit of its depth distribution in a shallow, light-limited bay. We first describe the relationship between light availability and seagrass density along a depth gradient in an extensive unfragmented meadow (Alfacs bay, NE Spain). We then develop a simple mechanistic model to characterise system behaviour. In the field, we identified sharp decline in shoot density beyond a threshold of ∼1.9 m depth, shifting from a vegetated state to bare sand. The dynamic population model we developed assumes light-dependent growth and an inverse density-dependent mortality due to facilitation between shoots (mortality rate decreases as shoot density increases). The model closely tracked our empirical observations, and both the model and the field data showed signs of bistability. This strongly suggests that the depth limit of C. nodosa is a critical transition driven by photosynthetic light requirements. While the mechanisms still need to be confirmed with experimental evidence, recognizing the non-linear behaviour of C. nodosa meadows is vital not only in improving our understanding of light effects on seagrass dynamics, but also in managing shallow-water meadows. Given the shallow threshold (<2m), light-limited systems may experience significant and recalcitrant meadow retractions with even small changes in sediment and light conditions. Understanding the processes underlying meadow resilience can inform the maintenance and restoration of meadows worldwide.
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Affiliation(s)
- Elvira Mayol
- Institut Mediterrani d'Estudis Avançats (IMEDEA-CSIC), Carrer Miquel Marqués 21, 07190, Esporles, Spain.
| | - Jordi Boada
- Laboratoire d'Océanographie de Villefranche, Sorbonne Université, Villefranche-sur-Mer, France
| | - Marta Pérez
- Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals, Facultat de Biologia, Universitat de Barcelona, Avinguda Diagonal 643, 08028, Barcelona, Spain
| | - Neus Sanmartí
- Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals, Facultat de Biologia, Universitat de Barcelona, Avinguda Diagonal 643, 08028, Barcelona, Spain
| | - Mario Minguito-Frutos
- Centre d'Estudis Avançats de Blanes (CEAB-CSIC), Carrer d'Accés a la cala Sant Francesc 14, 17300, Blanes, Spain
| | - Rohan Arthur
- Centre d'Estudis Avançats de Blanes (CEAB-CSIC), Carrer d'Accés a la cala Sant Francesc 14, 17300, Blanes, Spain; Nature Conservation Foundation, 1311 Amritha, 12th Cross, Vijayanagara 1st Stage, Mysore, 570017, India
| | - Teresa Alcoverro
- Centre d'Estudis Avançats de Blanes (CEAB-CSIC), Carrer d'Accés a la cala Sant Francesc 14, 17300, Blanes, Spain; Nature Conservation Foundation, 1311 Amritha, 12th Cross, Vijayanagara 1st Stage, Mysore, 570017, India
| | - David Alonso
- Centre d'Estudis Avançats de Blanes (CEAB-CSIC), Carrer d'Accés a la cala Sant Francesc 14, 17300, Blanes, Spain
| | - Javier Romero
- Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals, Facultat de Biologia, Universitat de Barcelona, Avinguda Diagonal 643, 08028, Barcelona, Spain
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Llabrés E, Mayol E, Marbà N, Sintes T. A mathematical model for inter‐specific interactions in seagrasses. OIKOS 2022. [DOI: 10.1111/oik.09296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Eva Llabrés
- Inst. for Cross‐Disciplinary Physics and Complex Systems, IFISC (CSIC‐UIB), Univ. de les Illes Balears Palma de Mallorca Spain
| | - Elvira Mayol
- Dept of Global Change Research, Mediterranean Inst. for Advanced Studies, IMEDEA (CSIC‐UIB) Esporles (Mallorca) Spain
| | - Núria Marbà
- Dept of Global Change Research, Mediterranean Inst. for Advanced Studies, IMEDEA (CSIC‐UIB) Esporles (Mallorca) Spain
| | - Tomàs Sintes
- Inst. for Cross‐Disciplinary Physics and Complex Systems, IFISC (CSIC‐UIB), Univ. de les Illes Balears Palma de Mallorca Spain
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3
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Spatial patterns in ecological systems: from microbial colonies to landscapes. Emerg Top Life Sci 2022; 6:245-258. [PMID: 35678374 DOI: 10.1042/etls20210282] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 05/10/2022] [Accepted: 05/12/2022] [Indexed: 11/17/2022]
Abstract
Self-organized spatial patterns are ubiquitous in ecological systems and allow populations to adopt non-trivial spatial distributions starting from disordered configurations. These patterns form due to diverse nonlinear interactions among organisms and between organisms and their environment, and lead to the emergence of new (eco)system-level properties unique to self-organized systems. Such pattern consequences include higher resilience and resistance to environmental changes, abrupt ecosystem collapse, hysteresis loops, and reversal of competitive exclusion. Here, we review ecological systems exhibiting self-organized patterns. We establish two broad pattern categories depending on whether the self-organizing process is primarily driven by nonlinear density-dependent demographic rates or by nonlinear density-dependent movement. Using this organization, we examine a wide range of observational scales, from microbial colonies to whole ecosystems, and discuss the mechanisms hypothesized to underlie observed patterns and their system-level consequences. For each example, we review both the empirical evidence and the existing theoretical frameworks developed to identify the causes and consequences of patterning. Finally, we trace qualitative similarities across systems and propose possible ways of developing a more quantitative understanding of how self-organization operates across systems and observational scales in ecology.
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Calvo S, Pirrotta M, Tomasello A. Letter to the editor regarding the article "Taking advantage of seagrass recovery potential to develop novel and effective meadow rehabilitation methods" by Alagna et al., published in Marine Pollution Bulletin, 149: 2019 (110578). MARINE POLLUTION BULLETIN 2020; 158:111395. [PMID: 32568075 DOI: 10.1016/j.marpolbul.2020.111395] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 06/17/2020] [Accepted: 06/17/2020] [Indexed: 06/11/2023]
Abstract
Alagna et al. (2019) suggest new transplantation methods for Posidonia oceanica (Linnaeus) Delile, inspired by its natural recovery process after disturbance due to dredging operations for gas-pipelines. They observe that P. oceanica vegetative fragments naturally settled only on loose calcareous stones deployed to fill the trenches of the gas-pipeline. No recovery was noted on dead matte, sand and large calcarenitic boulders. Following a new pilot restoration project currently ongoing in the same area, we demonstrate that natural recovery also occurs on dead matte. After examining other alternative transplantation methods for P. oceanica, the Authors suggest using their "habitat enhancement units" method for the restoration of seagrasses, not only on rocky bottom but also on sand and other bare substrate requiring general environmental restoration. Here we express disagreement on certain issues reported in the paper.
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Affiliation(s)
- Sebastiano Calvo
- Department of Earth and Marine Science (DiSTeM), University of Palermo, Viale delle Scienze Ed. 16, 90128 Palermo, Italy.
| | - Maria Pirrotta
- Department of Earth and Marine Science (DiSTeM), University of Palermo, Viale delle Scienze Ed. 16, 90128 Palermo, Italy
| | - Agostino Tomasello
- Department of Earth and Marine Science (DiSTeM), University of Palermo, Viale delle Scienze Ed. 16, 90128 Palermo, Italy
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Ruiz-Reynés D, Gomila D. Distribution of growth directions in meadows of clonal plants. Phys Rev E 2019; 100:052208. [PMID: 31870011 DOI: 10.1103/physreve.100.052208] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Indexed: 11/07/2022]
Abstract
Clonal growth plants are abundant in both terrestrial and marine ecosystems. Some marine species are particularly important since they provide essential ecosystem services in the shores of all continents except Antarctica. For the appropriate modelization of clonal growth the discretization of the growth direction angle has to be carefully treated to correctly describe the dynamics of the meadow. Specifically, determining the minimum number of growth directions is important to maximize the efficiency of numerical simulations. We show that the presence of neutral modes in the growth direction angle tends to make the distribution of the growth directions uniform in the presence of noise, allowing us to choose the minimal number of discrete angles compatible with the branching. We also show that the formation of spatial patterns induces small differences in the population density within these different growth directions.
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Affiliation(s)
- D Ruiz-Reynés
- IFISC (CSIC-UIB), Instituto de Física Interdisciplinar y Sistemas Complejos, Campus Universitat de les Illes Balears, E-07122 Palma de Mallorca, Spain
| | - D Gomila
- IFISC (CSIC-UIB), Instituto de Física Interdisciplinar y Sistemas Complejos, Campus Universitat de les Illes Balears, E-07122 Palma de Mallorca, Spain
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Vieira VMNCS, Lopes IE, Creed JC. A model for the biomass-density dynamics of seagrasses developed and calibrated on global data. BMC Ecol 2019; 19:4. [PMID: 30683077 PMCID: PMC6346591 DOI: 10.1186/s12898-019-0221-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Accepted: 01/16/2019] [Indexed: 12/02/2022] Open
Abstract
BACKGROUND Seagrasses are foundation species in estuarine and lagoon systems, providing a wide array of services for the ecosystem and the human population. Understanding the dynamics of their stands is essential in order to better assess natural and anthropogenic impacts. It is usually considered that healthy seagrasses aim to maximize their stand biomass (g DW m-2) which may be constrained by resource availability i.e., the local environment sets a carrying capacity. Recently, this paradigm has been tested and reassessed, and it is believed that seagrasses actually maximize their efficiency of space occupation-i.e., aim to reach an interspecific boundary line (IBL)-as quick as possible. This requires that they simultaneously grow in biomass and iterate new shoots to increase density. However, this strategy depresses their biomass potential. RESULTS to comply with this new paradigm, we developed a seagrass growth model that updates the carrying capacities for biomass and shoot density from the seagrass IBL at each time step. The use of a joint biomass and density growth rates enabled parameter estimation with twice the sample sizes and made the model less sensitive to episodic error in either of the variables. The use of instantaneous growth rates enabled the model to be calibrated with data sampled at widely different time intervals. We used data from 24 studies of six seagrass species scattered worldwide. The forecasted allometric biomass-density growth trajectories fit these observations well. Maximum growth and decay rates were found consistently for each species. The growth rates varied seasonally, matching previous observations. CONCLUSIONS State-of-art models predicting both biomass and shoot density in seagrass have not previously incorporated our observation across many seagrass species that dynamics depend on current state relative to IBL. Our model better simulates the biomass-density dynamics of seagrass stands while shedding light on its intricacies. However, it is only valid for established patches where dynamics involve space-filling, not for colonization of new areas.
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Affiliation(s)
- Vasco M. N. C. S. Vieira
- MARETEC, Instituto Superior Técnico, Universidade Técnica de Lisboa, Av. Rovisco Pais, 1049-001 Lisbon, Portugal
| | - Inês E. Lopes
- MARETEC, Instituto Superior Técnico, Universidade Técnica de Lisboa, Av. Rovisco Pais, 1049-001 Lisbon, Portugal
| | - Joel C. Creed
- Departamento de Ecologia, Instituto de Biologia Roberto Alcântara Gomes, Universidade do Estado do Rio de Janeiro, Rua São Francisco Xavier 524, Rio de Janeiro, RJ 20559-900 Brazil
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Whitehead S, Cambridge ML, Renton M. A functional-structural model of ephemeral seagrass growth influenced by environment. ANNALS OF BOTANY 2018; 121:897-908. [PMID: 29370337 PMCID: PMC5906912 DOI: 10.1093/aob/mcx156] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Accepted: 10/23/2017] [Indexed: 05/12/2023]
Abstract
Background and Aims Ephemeral seagrasses that respond rapidly to environmental changes are important marine habitats. However, they are under threat due to human activity and are logistically difficult and expensive to study. This study aimed to develop a new functional-structural environmentally dependent model of ephemeral seagrass, able to integrate our understanding of ephemeral seagrass growth dynamics and assess options for potential management interventions, such as seagrass transplantation. Methods A functional-structural plant model was developed in which growth and senescence rates are mechanistically linked to environmental variables. The model was parameterized and validated for a population of Halophila stipulacea in the Persian Gulf. Key Results There was a good match between empirical and simulated results for the number of apices, net rhizome length or net number of internodes using a 330 d simulation. Simulated data were more variable than empirical data. Simulated structural patterns of seagrass rhizome growth qualitatively matched empirical observations. Conclusions This new model successfully simulates the environmentally dependent growth and senescence rates of our case-study ephemeral seagrass species. It produces numerical and visual outputs that help synthesize our understanding of how the influence of environmental variables on plant functional processes affects overall growth patterns. The model can also be used to assess the potential outcomes of management interventions like seagrass transplantation, thus providing a useful management tool. It is freely available and easily adapted for new species and locations, although validation with more species and environments is required.
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Affiliation(s)
- S Whitehead
- School of Biological Sciences, The University of Western Australia, Crawley, WA, Australia
| | - M L Cambridge
- School of Biological Sciences, The University of Western Australia, Crawley, WA, Australia
- The UWA Oceans Institute, The University of Western Australia, Crawley, WA, Australia
| | - M Renton
- School of Biological Sciences, The University of Western Australia, Crawley, WA, Australia
- School of Agriculture and Environment, The University of Western Australia, Crawley, WA, Australia
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Becheler R, Masson JP, Arnaud-Haond S, Halkett F, Mariette S, Guillemin ML, Valero M, Destombe C, Stoeckel S. ClonEstiMate, a Bayesian method for quantifying rates of clonality of populations genotyped at two-time steps. Mol Ecol Resour 2017; 17:e251-e267. [DOI: 10.1111/1755-0998.12698] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 06/01/2017] [Accepted: 06/22/2017] [Indexed: 11/29/2022]
Affiliation(s)
- Ronan Becheler
- Evolutionary Biology and Ecology of Algae; CNRS; Sorbonne Universités; UPMC; University of Paris VI; UC; UACH; UMI 3614; Roscoff France
| | - Jean-Pierre Masson
- Institute for Genetics; Environment and Plant Protection; INRA; UMR1349; Le Rheu France
| | - Sophie Arnaud-Haond
- Ifremer; MARBEC (Marine Biodiversity, Exploitation and Conservation); Boulevard Jean Monet; 34200 SETE
| | | | | | - Marie-Laure Guillemin
- Evolutionary Biology and Ecology of Algae; CNRS; Sorbonne Universités; UPMC; University of Paris VI; UC; UACH; UMI 3614; Roscoff France
- Facultad de Ciencias; Instituto de Ciencias Ambientales y Evolutivas; Universidad Austral de Chile; Valdivia Chile
| | - Myriam Valero
- Evolutionary Biology and Ecology of Algae; CNRS; Sorbonne Universités; UPMC; University of Paris VI; UC; UACH; UMI 3614; Roscoff France
| | - Christophe Destombe
- Evolutionary Biology and Ecology of Algae; CNRS; Sorbonne Universités; UPMC; University of Paris VI; UC; UACH; UMI 3614; Roscoff France
| | - Solenn Stoeckel
- Institute for Genetics; Environment and Plant Protection; INRA; UMR1349; Le Rheu France
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9
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Ruiz-Reynés D, Gomila D, Sintes T, Hernández-García E, Marbà N, Duarte CM. Fairy circle landscapes under the sea. SCIENCE ADVANCES 2017; 3:e1603262. [PMID: 28782035 PMCID: PMC5540242 DOI: 10.1126/sciadv.1603262] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Accepted: 06/28/2017] [Indexed: 05/15/2023]
Abstract
Short-scale interactions yield large-scale vegetation patterns that, in turn, shape ecosystem function across landscapes. Fairy circles, which are circular patches bare of vegetation within otherwise continuous landscapes, are characteristic features of semiarid grasslands. We report the occurrence of submarine fairy circle seascapes in seagrass meadows and propose a simple model that reproduces the diversity of seascapes observed in these ecosystems as emerging from plant interactions within the meadow. These seascapes include two extreme cases, a continuous meadow and a bare landscape, along with intermediate states that range from the occurrence of persistent but isolated fairy circles, or solitons, to seascapes with multiple fairy circles, banded vegetation, and "leopard skin" patterns consisting of bare seascapes dotted with plant patches. The model predicts that these intermediate seascapes extending across kilometers emerge as a consequence of local demographic imbalances along with facilitative and competitive interactions among the plants with a characteristic spatial scale of 20 to 30 m, consistent with known drivers of seagrass performance. The model, which can be extended to clonal growth plants in other landscapes showing fairy rings, reveals that the different seascapes observed hold diagnostic power as to the proximity of seagrass meadows to extinction points that can be used to identify ecosystems at risks.
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Affiliation(s)
- Daniel Ruiz-Reynés
- IFISC (Instituto de Física Interdisciplinar y Sistemas Complejos) [Universidad Illes Baleares–Consejo Superior de Investigaciones Científicas (UIB-CSIC)], Campus Universitat Illes Balears, 07122 Palma de Mallorca, Spain
| | - Damià Gomila
- IFISC (Instituto de Física Interdisciplinar y Sistemas Complejos) [Universidad Illes Baleares–Consejo Superior de Investigaciones Científicas (UIB-CSIC)], Campus Universitat Illes Balears, 07122 Palma de Mallorca, Spain
| | - Tomàs Sintes
- IFISC (Instituto de Física Interdisciplinar y Sistemas Complejos) [Universidad Illes Baleares–Consejo Superior de Investigaciones Científicas (UIB-CSIC)], Campus Universitat Illes Balears, 07122 Palma de Mallorca, Spain
| | - Emilio Hernández-García
- IFISC (Instituto de Física Interdisciplinar y Sistemas Complejos) [Universidad Illes Baleares–Consejo Superior de Investigaciones Científicas (UIB-CSIC)], Campus Universitat Illes Balears, 07122 Palma de Mallorca, Spain
| | - Núria Marbà
- Department of Global Change Research, IMEDEA (Mediterranean Institute for Advanced Studies) (UIB-CSIC), Miquel Marqués 21, 07190 Esporles, Spain
| | - Carlos M. Duarte
- King Abdullah University of Science and Technology, Red Sea Research Center, Thuwal 23955-6900, Saudi Arabia
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Evidences of adaptive traits to rocky substrates undermine paradigm of habitat preference of the Mediterranean seagrass Posidonia oceanica. Sci Rep 2015; 5:8804. [PMID: 25740176 PMCID: PMC4350093 DOI: 10.1038/srep08804] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Accepted: 02/05/2015] [Indexed: 11/08/2022] Open
Abstract
Posidonia oceanica meadows are acknowledged as one of the most valuable ecosystems of the Mediterranean Sea. P. oceanica has been historically described as a species typically growing on mobile substrates whose development requires precursor communities. Here we document for the first time the extensive presence of sticky hairs covering P. oceanica seedling roots. Adhesive root hairs allow the seedlings to firmly anchor to rocky substrates with anchorage strength values up to 5.23 N, regardless of the presence of algal cover and to colonise bare rock without the need for precursor assemblages to facilitate settlement. Adhesive root hairs are a morphological trait common on plants living on rocks in high-energy habitats, such as the riverweed Podostemaceae and the seagrass Phyllospadix scouleri. The presence of adhesive root hairs in P. oceanica juveniles suggests a preference of this species for hard substrates. Such an adaptation leads to hypothesize a new microsite driven bottleneck in P. oceanica seedling survival linked to substrate features. The mechanism described can favour plant establishment on rocky substrates, in contrast with traditional paradigms. This feature may have strongly influenced P. oceanica pattern of colonisation through sexual propagules in both the past and present.
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Ruiz-Montoya L, Lowe RJ, Kendrick GA. Contemporary connectivity is sustained by wind- and current-driven seed dispersal among seagrass meadows. MOVEMENT ECOLOGY 2015; 3:9. [PMID: 25897403 PMCID: PMC4404238 DOI: 10.1186/s40462-015-0034-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Accepted: 02/26/2015] [Indexed: 05/22/2023]
Abstract
BACKGROUND Seagrasses are clonal marine plants that form important biotic habitats in many tropical and temperate coastal ecosystems. While there is a reasonable understanding of the dynamics of asexual (vegetative) growth in seagrasses, sexual reproduction and the dispersal pathways of the seeds remain poorly studied. Here we address the potential for a predominantly clonal seagrass, P. australis, to disperse over long distances by movement of floating fruit via wind and surface currents within the coastal waters of Perth, Western Australia. We first simulated the dominant atmospheric and ocean forcing conditions that are known to disperse these seagrass seeds using a three-dimensional numerical ocean circulation model. Field observations obtained at 8 sites across the study area were used to validate the model performance over ~2 months in summer when buoyant P. australis fruit are released into the water column. P. australis fruit dispersal trajectories were then quantified throughout the region by incorporating key physical properties of the fruit within the transport model. The time taken for the floating fruit to release their seed (dehiscence) was incorporated into the model based on laboratory measurements, and was used to predict the settlement probability distributions across the model domain. RESULTS The results revealed that high rates of local and regional demographic connectivity among P. australis meadows are achieved via contemporary seed dispersal. Dispersal of seeds via floating fruit has the potential to regularly connect meadows at distances of 10s of kilometres (50% of seeds produced) and infrequently for meadows at distances 100 s km (3% of seeds produced). CONCLUSIONS The spatial patterns of seed dispersal were heavily influenced by atmospheric and oceanographic conditions, which generally drove a northward pattern of connectivity on a regional scale, but with geographical barriers influencing finer-scale connectivity pathways at some locations. Such levels of seed dispersal infer greater levels of ecological and genetic connectivity and suggest that seagrasses are not just strongly clonal.
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Affiliation(s)
- Leonardo Ruiz-Montoya
- />The School of Earth and Environment, The University of Western Australia, Crawley, Western Australia Australia
- />The School of Plant Biology, The University of Western Australia, Crawley, Western Australia Australia
- />The University of Western Australia Oceans Institute, Crawley, Western Australia Australia
| | - Ryan J Lowe
- />The School of Earth and Environment, The University of Western Australia, Crawley, Western Australia Australia
- />The University of Western Australia Oceans Institute, Crawley, Western Australia Australia
- />ARC Centre of Excellence for Coral Reef Studies, Crawley, Western Australia Australia
| | - Gary A Kendrick
- />The School of Plant Biology, The University of Western Australia, Crawley, Western Australia Australia
- />The University of Western Australia Oceans Institute, Crawley, Western Australia Australia
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12
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Govers LL, de Brouwer JHF, Suykerbuyk W, Bouma TJ, Lamers LPM, Smolders AJP, van Katwijk MM. Toxic effects of increased sediment nutrient and organic matter loading on the seagrass Zostera noltii. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2014; 155:253-60. [PMID: 25064458 DOI: 10.1016/j.aquatox.2014.07.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Revised: 06/11/2014] [Accepted: 07/06/2014] [Indexed: 05/27/2023]
Abstract
As a result of anthropogenic disturbances and natural stressors, seagrass beds are often patchy and heterogeneous. The effects of high loads of nutrients and organic matter in patch development and expansion in heterogeneous seagrass beds have, however, poorly been studied. We experimentally assessed the in situ effects of sediment quality on seagrass (Zostera noltii) patch dynamics by studying patch (0.35 m diameter) development and expansion for 4 sediment treatments: control, nutrient addition (NPK), organic matter addition (OM) and a combination (NPK+OM). OM addition strongly increased porewater sulfide concentrations whereas NPK increased porewater ammonium, nitrate and phosphate concentrations. As high nitrate concentrations suppressed sulfide production in NPK+OM, this treatment was biogeochemically comparable to NPK. Sulfide and ammonium concentrations differed within treatments, but over a 77 days period, seagrass patch survival and expansion were impaired by all additions compared to the control treatment. Expansion decreased at porewater ammonium concentrations >2,000 μmol L(-1). Mother patch biomass was not affected by high porewater ammonium concentrations as a result of its detoxification by higher seagrass densities. Sulfide concentrations >1,000 μmol L(-1) were toxic to both patch expansion and mother patch. We conclude that patch survival and expansion are constrained at high loads of nutrients or organic matter as a result of porewater ammonium or sulfide toxicity.
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Affiliation(s)
- Laura L Govers
- Department of Environmental Science, Institute for Water and Wetland Research, Radboud University Nijmegen, Faculty of Science, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands.
| | - Jan H F de Brouwer
- Department of Environmental Science, Institute for Water and Wetland Research, Radboud University Nijmegen, Faculty of Science, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Wouter Suykerbuyk
- Department of Environmental Science, Institute for Water and Wetland Research, Radboud University Nijmegen, Faculty of Science, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands; Department of Spatial Ecology, NIOZ Yerseke Royal Netherlands Institute for Sea Research, P.O. Box 140, 4400 AC Yerseke, The Netherlands
| | - Tjeerd J Bouma
- Department of Spatial Ecology, NIOZ Yerseke Royal Netherlands Institute for Sea Research, P.O. Box 140, 4400 AC Yerseke, The Netherlands
| | - Leon P M Lamers
- Department of Aquatic Ecology and Environmental Biology, Institute for Water and Wetland Research, Radboud University Nijmegen, Faculty of Science, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Alfons J P Smolders
- Department of Aquatic Ecology and Environmental Biology, Institute for Water and Wetland Research, Radboud University Nijmegen, Faculty of Science, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Marieke M van Katwijk
- Department of Environmental Science, Institute for Water and Wetland Research, Radboud University Nijmegen, Faculty of Science, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
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13
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Duarte CM, Sintes T, Marbà N. Assessing the CO2capture potential of seagrass restoration projects. J Appl Ecol 2013. [DOI: 10.1111/1365-2664.12155] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Carlos M. Duarte
- Department of Global Change Research; IMEDEA (UIB-CSIC); Miquel Marqués 21 07190 Esporles Spain
- The UWA Oceans Institute; and School of Plant Biology; University of Western Australia; 35 Stirling Highway Crawley WA 6009 Australia
- Faculty of Marine Sciences; King Abdulaziz University; PO Box 80207 Jeddah 21589 Saudi Arabia
| | - Tomás Sintes
- Instituto de Física Interdisciplinar y Sistemas Complejos; IFISC (UIB-CSIC); Universitat de les Illes Balears; E-07122 Palma de Mallorca Spain
| | - Núria Marbà
- Department of Global Change Research; IMEDEA (UIB-CSIC); Miquel Marqués 21 07190 Esporles Spain
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Balestri E, Lardicci C. Nursery-propagated plants from seed: a novel tool to improve the effectiveness and sustainability of seagrass restoration. J Appl Ecol 2012. [DOI: 10.1111/j.1365-2664.2012.02197.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Elena Balestri
- Dipartimento di Biologia; Pisa University; Via Derna 1; 56100; Pisa; Italy
| | - Claudio Lardicci
- Dipartimento di Biologia; Pisa University; Via Derna 1; 56100; Pisa; Italy
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15
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Arnaud-Haond S, Duarte CM, Diaz-Almela E, Marbà N, Sintes T, Serrão EA. Implications of extreme life span in clonal organisms: millenary clones in meadows of the threatened seagrass Posidonia oceanica. PLoS One 2012; 7:e30454. [PMID: 22312426 PMCID: PMC3270012 DOI: 10.1371/journal.pone.0030454] [Citation(s) in RCA: 146] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2011] [Accepted: 12/16/2011] [Indexed: 11/18/2022] Open
Abstract
The maximum size and age that clonal organisms can reach remains poorly known, although we do know that the largest natural clones can extend over hundreds or thousands of metres and potentially live for centuries. We made a review of findings to date, which reveal that the maximum clone age and size estimates reported in the literature are typically limited by the scale of sampling, and may grossly underestimate the maximum age and size of clonal organisms. A case study presented here shows the occurrence of clones of slow-growing marine angiosperm Posidonia oceanica at spatial scales ranging from metres to hundreds of kilometres, using microsatellites on 1544 sampling units from a total of 40 locations across the Mediterranean Sea. This analysis revealed the presence, with a prevalence of 3.5 to 8.9%, of very large clones spreading over one to several (up to 15) kilometres at the different locations. Using estimates from field studies and models of the clonal growth of P. oceanica, we estimated these large clones to be hundreds to thousands of years old, suggesting the evolution of general purpose genotypes with large phenotypic plasticity in this species. These results, obtained combining genetics, demography and model-based calculations, question present knowledge and understanding of the spreading capacity and life span of plant clones. These findings call for further research on these life history traits associated with clonality, considering their possible ecological and evolutionary implications.
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16
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Multifractal pattern and process during a recent period of forest expansion in a temperate mountainous region of China. ECOL INFORM 2011. [DOI: 10.1016/j.ecoinf.2011.08.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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17
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Renton M, Airey M, Cambridge ML, Kendrick GA. Modelling seagrass growth and development to evaluate transplanting strategies for restoration. ANNALS OF BOTANY 2011; 108:1213-23. [PMID: 21821624 PMCID: PMC3189841 DOI: 10.1093/aob/mcr131] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2010] [Accepted: 03/23/2011] [Indexed: 05/12/2023]
Abstract
BACKGROUND AND AIMS Seagrasses are important marine plants that are under threat globally. Restoration by transplanting vegetative fragments or seedlings into areas where seagrasses have been lost is possible, but long-term trial data are limited. The goal of this study is to use available short-term data to predict long-term outcomes of transplanting seagrass. METHODS A functional-structural plant model of seagrass growth that integrates data collected from short-term trials and experiments is presented. The model was parameterized for the species Posidonia australis, a limited validation of the model against independent data and a sensitivity analysis were conducted and the model was used to conduct a preliminary evaluation of different transplanting strategies. KEY RESULTS The limited validation was successful, and reasonable long-term outcomes could be predicted, based only on short-term data. CONCLUSIONS This approach for modelling seagrass growth and development enables long-term predictions of the outcomes to be made from different strategies for transplanting seagrass, even when empirical long-term data are difficult or impossible to collect. More validation is required to improve confidence in the model's predictions, and inclusion of more mechanism will extend the model's usefulness. Marine restoration represents a novel application of functional-structural plant modelling.
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Affiliation(s)
- Michael Renton
- School of Plant Biology, University of Western Australia, Crawley, 6009, Australia.
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18
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Wong S, Anand M, Bauch CT. Agent-based modelling of clonal plant propagation across space: Recapturing fairy rings, power laws and other phenomena. ECOL INFORM 2011. [DOI: 10.1016/j.ecoinf.2010.11.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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19
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Mony C, Garbey M, Smaoui M, Benot ML. Large scale parameter study of an individual-based model of clonal plant with volunteer computing. Ecol Modell 2011. [DOI: 10.1016/j.ecolmodel.2010.10.014] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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20
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Uhrin AV, Hall MO, Merello MF, Fonseca MS. Survival and Expansion of Mechanically Transplanted Seagrass Sods. Restor Ecol 2009. [DOI: 10.1111/j.1526-100x.2008.00376.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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21
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Yamakita T, Nakaoka M. Scale dependency in seagrass dynamics: how does the neighboring effect vary with grain of observation? POPUL ECOL 2008. [DOI: 10.1007/s10144-008-0119-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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22
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Allowing macroalgae growth forms to emerge: Use of an agent-based model to understand the growth and spread of macroalgae in Florida coral reefs, with emphasis on Halimeda tuna. Ecol Modell 2008. [DOI: 10.1016/j.ecolmodel.2008.04.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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23
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Arnaud-Haond S, Duarte CM, Alberto F, Serrão EA. Standardizing methods to address clonality in population studies. Mol Ecol 2007; 16:5115-39. [PMID: 17944846 DOI: 10.1111/j.1365-294x.2007.03535.x] [Citation(s) in RCA: 326] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Although clonal species are dominant in many habitats, from unicellular organisms to plants and animals, ecological and particularly evolutionary studies on clonal species have been strongly limited by the difficulty in assessing the number, size and longevity of genetic individuals within a population. The development of molecular markers has allowed progress in this area, and although allozymes remain of limited use due to their typically low level of polymorphism, more polymorphic markers have been discovered during the last decades, supplying powerful tools to overcome the problem of clonality assessment. However, population genetics studies on clonal organisms lack a standardized framework to assess clonality, and to adapt conventional data analyses to account for the potential bias due to the possible replication of the same individuals in the sampling. Moreover, existing studies used a variety of indices to describe clonal diversity and structure such that comparison among studies is difficult at best. We emphasize the need for standardizing studies on clonal organisms, and particularly on clonal plants, in order to clarify the way clonality is taken into account in sampling designs and data analysis, and to allow further comparison of results reported in distinct studies. In order to provide a first step towards a standardized framework to address clonality in population studies, we review, on the basis of a thorough revision of the literature on population structure of clonal plants and of a complementary revision on other clonal organisms, the indices and statistics used so far to estimate genotypic or clonal diversity and to describe clonal structure in plants. We examine their advantages and weaknesses as well as various conceptual issues associated with statistical analyses of population genetics data on clonal organisms. We do so by testing them on results from simulations, as well as on two empirical data sets of microsatellites of the seagrasses Posidonia oceanica and Cymodocea nodosa. Finally, we also propose a selection of new indices and methods to estimate clonal diversity and describe clonal structure in a way that should facilitate comparison between future studies on clonal plants, most of which may be of interest for clonal organisms in general.
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Affiliation(s)
- S Arnaud-Haond
- CCMAR - CIMAR Laboratório Associado, Univ. Algarve, Gambelas, 8005-139, Faro, Portugal.
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24
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Sintes T, Moragues E, Traveset A, Rita J. Clonal growth dynamics of the invasive Carpobrotus affine acinaciformis in Mediterranean coastal systems: A non-linear model. Ecol Modell 2007. [DOI: 10.1016/j.ecolmodel.2007.03.027] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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25
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Brun FG, Cummaudo F, Olivé I, Vergara JJ, Pérez-Lloréns JL. Clonal extent, apical dominance and networking features in the phalanx angiosperm Zostera noltii Hornem. MARINE BIOLOGY 2007; 151:1917-1927. [PMID: 30363820 PMCID: PMC6182604 DOI: 10.1007/s00227-007-0627-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2006] [Accepted: 01/17/2007] [Indexed: 05/29/2023]
Abstract
Disaggregating seagrass meadows and studying its components separately (clones, ramets, shoots) can provide us insights on meadow dynamics and growth patterns. The clonal growth, dependent upon clonal rules may regulate and impose constraints to plant architecture and, therefore, determine how individual clones evolve into the environment. In order to investigate the relationship between clonal growth rules and clone architecture, the belowground network architecture of single-clones of the seagrass Zostera noltii was studied. Networks were traced in situ after washing out the overlying sediment, and network characteristics were measured using digital analysis: area covered by clone, total rhizome length, type of rhizomatic axes (main, secondary, tertiary, quaternary), number and length of the internodes, branching angles and branching frequencies. This approach revealed that Z. noltii is able to develop into large clones integrating up to 300 internodes, 676 cm of rhizome, 208 shoots and 4,300 cm2 of plant area. Internodal length depended on both, the distance to the apical shoot (time effect) and the axes type (apical dominance effect). However, average branching angle was independent of axis type (average 58.3 ± 0.75), but varied significantly depending on the distance from the apical shoot. This average branching angle allows Z. noltii maximize the rate of centrifugal expansion, maintaining a high density in colonized areas to produce close stands but also minimizing the investment in belowground biomass and ramets overlapping. The clonal architecture of Z. noltii seems to be regulated by the interaction of both, apical dominance strength and clonal integration distance. Moreover, clonal growth rules and growth pattern seem to constrain clonality through (clonal) plant architecture regulations (i.e. branching is restricted in secondary axes, similar average branching angles regardless the axes, the higher the distance to the apex the higher the number of internodes in secondary axes, shorter internodes in secondary and tertiary axes). Future research efforts should focus on how these complex relationships between apical dominance and clonal integration interact to elucidate the temporal (seasonal) and spatial scales of both processes and the outcome at the plant architectural level.
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Affiliation(s)
- Fernando G. Brun
- Netherlands Institute of Ecology (NIOO-KNAW), Centre for Estuarine and Marine Ecology, Korringaweg 7, 4401 NT Yerseke, The Netherlands
- Departamento de Biología. Área de Ecología, Universidad de Cádiz, Facultad de Ciencias del Mar y Ambientales, 11510 Puerto Real, Cádiz, Spain
| | - Fabio Cummaudo
- Ecology and Computational Hydrodynamics in Oceanography, Istituto Nazionale di Oceanografia e di Geofisica Sperimentale (OGS), Borgo Grotta Gigante 42/C, 34010 Sgonico, Trieste, Italy
| | - Irene Olivé
- Departamento de Biología. Área de Ecología, Universidad de Cádiz, Facultad de Ciencias del Mar y Ambientales, 11510 Puerto Real, Cádiz, Spain
| | - Juan José Vergara
- Departamento de Biología. Área de Ecología, Universidad de Cádiz, Facultad de Ciencias del Mar y Ambientales, 11510 Puerto Real, Cádiz, Spain
| | - José Lucas Pérez-Lloréns
- Departamento de Biología. Área de Ecología, Universidad de Cádiz, Facultad de Ciencias del Mar y Ambientales, 11510 Puerto Real, Cádiz, Spain
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O'Malley L, Kozma B, Korniss G, Rácz Z, Caraco T. Fisher waves and front roughening in a two-species invasion model with preemptive competition. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2006; 74:041116. [PMID: 17155031 DOI: 10.1103/physreve.74.041116] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2006] [Indexed: 05/12/2023]
Abstract
We study front propagation when an invading species competes with a resident; we assume nearest-neighbor preemptive competition for resources in an individual-based, two-dimensional lattice model. The asymptotic front velocity exhibits an effective power-law dependence on the difference between the two species' clonal propagation rates (key ecological parameters). The mean-field approximation behaves similarly, but the power law's exponent slightly differs from the individual-based model's result. We also study roughening of the front, using the framework of nonequilibrium interface growth. Our analysis indicates that initially flat, linear invading fronts exhibit Kardar-Parisi-Zhang (KPZ) roughening in one transverse dimension. Further, this finding implies, and is also confirmed by simulations, that the temporal correction to the asymptotic front velocity is of O(t(-2/3)).
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Affiliation(s)
- L O'Malley
- Department of Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180-3590, USA.
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27
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Alberto F, Gouveia L, Arnaud-Haond S, Pérez-Lloréns JL, Duarte CM, Serrão EA. Within-population spatial genetic structure, neighbourhood size and clonal subrange in the seagrass Cymodocea nodosa. Mol Ecol 2005; 14:2669-81. [PMID: 16029469 DOI: 10.1111/j.1365-294x.2005.02640.x] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Abstract The extent of clonality within populations strongly influences their spatial genetic structure (SGS), yet this is hardly ever thoroughly analysed. We employed spatial autocorrelation analysis to study effects of sexual and clonal reproduction on dispersal of the dioecious seagrass Cymodocea nodosa. Analyses were performed both at genet level (i.e. excluding clonal repeats) and at ramet level. Clonal structure was characterized by the clonal subrange, a spatial measure of the linear limits where clonality still affects SGS. We show that the clonal subrange is equivalent to the distance where the probability of clonal identity approaches zero. This combined approach was applied to two meadows with different levels of disturbance, Cadiz (stable) and Alfacs (disturbed). Genotypic richness, the proportion of the sample representing distinct genotypes, was moderate (0.38 Cadiz, 0.46 Alfacs) mostly due to dominance of a few clones. Expected heterozygosities were comparable to those found in other clonal plants. SGS analyses at the genet level revealed extremely restricted gene dispersal in Cadiz (Sp = 0.052, a statistic reflecting the decrease of pairwise kinship with distance), the strongest SGS found for seagrass species, comparable only to values for selfing herbaceous land plants. At Cadiz the clonal subrange extended across shorter distances (20-25 m) than in Alfacs (30-35 m). Comparisons of sexual and vegetative components of gene dispersal suggest that, as a dispersal vector within meadows, clonal spread is at least as important as sexual reproduction. The restricted dispersal and SGS pattern in both meadows indicates that the species follows a repeated seedling recruitment strategy.
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Affiliation(s)
- Filipe Alberto
- CCMAR, CIMAR-Laboratório Associado, University of Algarve, Campus de Gambelas, 8005-139 Faro, Portugal
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