Range Expansion Mechanisms of the Invasive Kelp Undaria Pinnatifida PDF Download

Author: Merle Bollen
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Author: Glen Andrew Thompson
Publisher:
ISBN:
Category : Intertidal ecology
Languages : en
Pages : 332

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Author: Kate James
Publisher:
ISBN:
Category : Invasive plants
Languages : en
Pages : 127

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Book Description
Macroalgal invasions can change the structure and function of benthic habitat, dominating space, altering primary productivity, nutrient cycles, and community composition. This is a serious concern for receiving environments. A major determinant of the geographic distribution of macroalgal species is water temperature. Investigating the population ecology, genetic variation and factors controlling the density and spread of invasive macroalgae towards the extent of their thermal distribution limits can therefore provide important insights into the potential range and ecological impacts both now and with future climate change. The kelp Undaria pinnatifida is a prolific and cosmopolitan invasive species. Undaria has invaded countries around the world across a variety of temperature regimes. Undaria displays a variable phenology at introduced locations; it is a winter annual in its native range, but sporophyte presence can vary from annual to year-round across its invasive range. Information is lacking on how Undaria phenology and impacts manifest under warm-temperate conditions. This work studies Undaria in northern New Zealand, one of the warmest-water populations in the world. I investigated how water temperature influenced the phenology and distribution of Undaria. In addition I examined some attributes of the invasion process for warm-water populations; I looked at the role mussel aquaculture plays in influencing the spread of Undaria to native habitats, how disturbance might facilitate the spread of Undaria to subtidal reefs, and the genetic composition of populations in northern New Zealand. Monitoring over three growth seasons revealed how Undaria in northern New Zealand displayed an annual growth cycle. Recruitment occurred when temperatures dropped below ~15 oC and density was minimal at temperatures above 20 oC. Sporophyte size and growth rates were comparable to those of cooler water populations but the seasonal cycle was compressed into a shorter timeframe. Undaria was found to proliferate on mussel farms and low numbers were found on reefs adjacent to farms, in shallow habitats lacking native macroalgal canopies. Undaria was rare in deeper habitats dominated by native macroalgal canopies, experimental canopy removal did not facilitate the spread of Undaria into these habitats at the site examined. This suggests that native canopy-forming species are not the sole factor prohibiting the invasion of Undaria to subtidal reef sites in this region. Genetic analysis of Undaria from all known populations in the North Island revealed very low genetic diversity in northern New Zealand. The presence of a single haplotype in northeastern New Zealand may indicate a particularly warm-tolerant strain and suggests thermal preadaptation may influence invasion success. An investigation into the global distribution and associated phenology of Undaria, and how this related to water temperature regimes, demonstrated how Undaria only occurred where winter temperatures dropped below ~15 oC and that persistent year-round populations were only present at sites where summer temperatures did not exceed 20 oC. This analysis also revealed that there are extensive areas of the world where Undaria does not occur that have temperature regimes suitable for Undaria colonisation. Such areas are potentially at risk from future invasion based on current temperature regimes. These thermal limits for Undaria indicate that populations in northern New Zealand are towards the limit of its distribution, with winter temperatures close to 15 oC, Undaria is unable to withstand warmer winter temperatures. Ocean warming is likely to restrict the potential geographic distribution of Undaria, particularly where winter temperatures exceed 15 oC. Increases in summer temperatures, which prolong the period during the year when temperatures exceed 20 oC, will reduce the annual persistence of Undaria. A limited annual presence of sporophytes at warmer locations may reduce the ecological impacts of Undaria invasion as compared to cooler water locations where sporophytes persist for a longer portion of the year.

Author: Inger Wallentinus
Publisher:
ISBN:
Category : Biodiversity conservation
Languages : en
Pages : 46

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Author: João Canning-Clode
Publisher: Walter de Gruyter GmbH & Co KG
ISBN: 3110438666
Category : Science
Languages : en
Pages : 488

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Book Description
When organisms are deliberately or accidentally introduced into a new ecosystem a biological invasion may take place. These so-called ‘invasive species’ may establish, spread and ecologically alter the invaded community. Biological invasions by animals, plants, pathogens or vectors are one of the greatest environmental and economic threats and, along with habitat destruction, a leading cause of global biodiversity loss. In this book, more than 50 worldwide invasion scientists cover our current understanding of biological invasions, its impacts, patterns and mechanisms in both aquatic and terrestrial systems.

Author: Trevor R. Burridge
Publisher:
ISBN: 9780643061804
Category : Undaria pinnatifida
Languages : en
Pages : 27

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Author: Zi-Min Hu
Publisher: Springer
ISBN: 9401775346
Category : Science
Languages : en
Pages : 398

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The book provides an overview of research on the remarkable diversity, adaptive genetic differentiation, and evolutionary complexity of intertidal macroalgae species. Through incorporating molecular data, ecological niche and model-based phylogeographic inference, this book presents the latest findings and hypotheses on the spatial distribution and evolution of seaweeds in the context of historical climate change (e.g. the Quaternary ice ages), contemporary global warming, and increased anthropogenic influences. The chapters in this book highlight past and current research on seaweed phylogeography and predict the future trends and directions. This book frames a number of research cases to review how biogeographic processes and interactive eco-genetic dynamics shaped the demographic histories of seaweeds, which furthermore enhances our understanding of speciation and diversification in the sea. Dr. Zi-Min Hu is an associate professor at Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China. Dr. Ceridwen Fraser is a senior lecturer at Fenner School of Environment and Society, Australian National University, Canberra, Australia.

Author: Stephen J. Hawkins
Publisher: Cambridge University Press
ISBN: 110841608X
Category : Nature
Languages : en
Pages : 535

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Book Description
A comprehensive account of how abiotic and biotic interactions shape patterns of coastal marine biodiversity and ecosystem processes globally.

Author: Jennifer Lorraine Madrid Thorson
Publisher:
ISBN:
Category :
Languages : en
Pages : 94

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Book Description
Adaptation to novel and changing environmental conditions is crucial for the persistence and range expansion of species in the context of biological invasions and climate change. Investigating the mechanisms by which populations adapt to environmental conditions is a key component of our understanding of adaptive evolution. Invasive species are prime candidates to study these mechanisms of adaptation. I have examined several mechanisms facilitating adaptation in a widely invasive and asexual aquatic snail, Potamopyrgus antipodarum. Classically, adaptation is attributed to selection on phenotypic variation which is encoded by genetic variation. I have investigated an assemblage of clonal lineages of P. antipodarum to understand how these clonal lineages respond to diverse habitats in the invasive range. The clonal lineages sampled represent habitat generalists, appearing in multiple diverse habitats. Phenotypic plasticity involves environmentally driven alterations to the phenotype independent of the genotype and is understood to be common and important among invasive species. I have examined the origins of phenotypic plasticity among invasive populations to understand if the trait of plasticity precedes an invasion event or if plasticity is a response to the novel range. The invasive lineages exhibited alterations in the reaction norm, supporting the hypothesis that invaders adapt through shifts in phenotypic plasticity. Finally, the alteration of methylation of DNA sequences can lead to shifts in levels of gene expression, which can result in phenotypic variation independent of genetic variation. I have quantified the variation of methylation among phenotypically diverged populations of the invader to understand if epigenetic variation is a mechanism that can explain adaptive phenotypic change among populations. Significant differences in the methylation of the two divergent populations support the potential for epigenetic alterations to facilitate rapid adaptation.

Author: Mark A. Ragan
Publisher: Springer Science & Business Media
ISBN: 9400940572
Category : Science
Languages : en
Pages : 566

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Book Description
Proceedings of the Twelfth International Seaweed Symposium, held in São Paulo, Brazil, July 27-August, 1986.