Ecophysiology of Habitat-Forming Seaweeds in a Changing Environment

Total Page:16

File Type:pdf, Size:1020Kb

Ecophysiology of Habitat-Forming Seaweeds in a Changing Environment Ecophysiology of habitat-forming seaweeds in a changing environment Emma Flukes BMarSci (Hons) A thesis submitted in fulfilment of the requirements for the Degree of Doctor of Philosophy in Marine Science Institute for Marine and Antarctic Studies (IMAS) University of Tasmania July 2015 This page intentionally left blank Declarations Statement of originality This thesis contains no material which has been accepted for a degree or diploma by the University or any other institution, except by way of background information and duly acknowledged in the thesis, and to the best of my knowledge and belief no material is previously published or written by another person except where due acknowledgement is made in the text of the thesis, nor does the thesis contain any material that infringes copyright. Signed: (Emma Flukes) Date: 3rd July 2015 Statement of authority of access This thesis may be available for loans and limited copying and communication in accordance with the Copyright Act 1968. Signed: (Emma Flukes) Date: 3rd July 2015 i Abstract ‘Ecosystem engineering’ species play a disproportionately important role in ecological systems by modifying (creating or destroying) habitat for other species. Understanding the impact of climate change is particularly critical for habitat-forming ecosystem engineers, as these species are generally facilitative and form the basis of hierarchically organised communities. In temperate marine environments, seaweed beds provide the fundamental structure of most shallow rocky reef communities. The coastline of southeastern Australia is warming at nearly four times the global average rate, with temperature increases occurring simultaneously with reduced nutrient availability due to strengthening seasonal incursions of warm, oligotrophic East Australian Current water. Climate change-driven range contractions in this area have already been documented for the canopy-forming Ecklonia radiata and Phyllospora comosa, while the areal coverage of Macrocystis pyrifera forests in Tasmania has declined by ~95% over the last 3-4 decades. Continued climatic change in this region is likely to impact on the physiological performance, reproductive capacity, survival, and ultimately the distribution of important habitat-forming seaweeds. Predicting the future impacts of climate change on species distributions has largely focused around the use of bioclimate envelope models (BEMs), which relate field observations of a species’ geographic distribution with environmental predictor variables to forecast its future distribution. This generalised modelling approach relies on the assumption that the physiological performance of a species under a given set of environmental conditions will be consistent across its range. However, Elser’s Growth Rate Hypothesis (GRH) predicts that the performance of photosynthetic organisms will vary with latitude due to increased selective pressure for rapid growth at high latitudes resulting from a growth season that is shortened by low light availability. Determining whether the GRH is applicable to habitat- forming seaweeds is a critical step to evaluating the efficacy of BEMs in predicting the future impacts of climate change on seaweed distributions. This thesis assesses the likely impacts of climate change on the physiology of the key biogenic habitat-forming seaweeds E. radiata, P. comosa and M. pyrifera in southeastern Australia. It employs a unique multivariate approach by assessing a complex suite of ii performance and ecophysiological characteristics including photophysiological indicators (photosynthetic characteristics via PAM fluorometry and concentration of photosynthetic pigments), nutrient uptake dynamics (% C, % N and C:N ratios), C metabolism (stable C isotope δ13C), and RNA:DNA ratios (as a proxy for growth rate). These physiological performance indicators are assessed within the conceptual framework of the GRH, and ultimately enable evaluation of the suitability of bioclimate envelope models for predicting the future performance and distribution of seaweeds under projected climate change scenarios. The thesis also investigates the likely impacts of climate change-driven loss of seaweed canopy on associated understory communities, which is critical in evaluating the use of BEMs as the effects of biotic (competitive) interactions among species are normally assumed to be unimportant. Chapter 2 investigates the influence of temperature and nitrate – two key environmental factors predicted to vary with future climate change – on the growth and ecophysiology of P. comosa from the northern and southern parts of its range. The physiological performance of this species was strongly temperature-dependent, but the deleterious effects of high temperatures on photosystem functionality were particularly pronounced in thalli originating from higher latitude. In contrast, nitrate availability played only a minor role in regulating seaweed physiology, suggesting that P. comosa at high latitudes may be less susceptible to nutrient stress than predicted by the GRH, but that the species will respond to predicted levels of warming with a loss of photosystem functionality unless rapid adaptation is possible. Chapter 3 explores the extent to which E. radiata and P. comosa may acclimatise to environmental change through phenotypic plasticity, and how this plasticity may vary across their latitudinal distributions. Thalli were transplanted from low to high latitudes (with appropriate controls) and their physiological performance monitored over four months. Trait expression was found to be largely under environmental control despite considerable ecophysiological differences between in situ populations from sites at high and low latitudes, demonstrating the considerable capacity of these species to acclimatise to a wide range of environmental conditions. Chapter 4 examines longer-term patterns in the seasonal in situ physiology of E. radiata, P. comosa and M. pyrifera in relation to environmental characteristics, and how this varies across their latitudinal and depth distributions. Temperature and irradiance were determined iii to be important regulators of seaweed physiology, but as with controlled laboratory experiments, nitrate availability was less important (except for M. pyrifera, which has very limited internal nitrogen storage capacity). Seaweeds at high latitudes were more adversely affected by high temperature and low nutrients during summer than their lower latitude counterparts (particularly in shallower water) seemingly due to the synergistic interaction of climatic stressors with high irradiance. Thus, while predicted climate-driven changes may impact similarly on seaweeds across their latitudinal distributions, high latitude populations are likely to experience increasingly stressful summers and may retreat to deeper waters and/or become more sparse and patchy. Chapter 5 assesses the impacts of potential climate change-driven thinning of seaweed canopy on the structure of associated understory community assemblages. Canopy thinning of E. radiata (as opposed to total canopy removal) affected a shift towards a foliose algal- dominated understory, with an associated loss of sponges, bryozoans and encrusting algae. While the structure of kelp-associated understory assemblages in southeastern Tasmania appears relatively stable, even partial loss of kelp canopy cover under future climate change scenarios will likely shift these communities towards a foliose algal-dominated state, which has important biodiversity implications. This thesis demonstrates the considerable capacity of seaweeds to respond to environmental change through phenotypic plasticity. While no evidence was found to support the GRH, multivariate ecophysiological measurements revealed subtle latitudinal variation in seaweed physiology in situ; indicating that a broad-scale climate envelope approach will not adequately predict the future performance and distribution of seaweeds under predicted climate change. The key findings of this thesis are: (1) a multivariate approach is required to describe and interpret seaweed physiology, particularly when attempting to detect organismal-scale changes that may ultimately impact on the performance and local survival of a species; (2) the GRH does not apply to E. radiata and P. comosa, but seaweeds at higher latitudes are more susceptible to increasing water temperature than is often assumed due to the synergistic interaction between high temperature and high irradiance over summer; and (3) bioclimate envelope models are unlikely to be a useful tool for predicting the performance and distribution of seaweeds under future climate change scenarios. iv Contents Declarations i Abstract ii Contents v List of Tables x List of Figures xi Acknowledgements xiv Statement of co-author contributions xvi 1 Introduction 1 2 Phenotypic plasticity and biogeographic variation in physiology of a habitat- forming seaweed: response to temperature and nitrate 10 2.1 Abstract ..................................................................................... 10 2.2 Introduction ................................................................................. 11 2.3 Materials and Methods .................................................................... 14 2.3.1 Study species, seaweed collection, and in situ sampling .............................14 2.3.2 Experimental design and culture conditions ...........................................15 2.3.3 Ecophysiological measurements .........................................................17
Recommended publications
  • Mechanisms of Ecosystem Stability for Kelp Beds in Urban Environments
    Mechanisms of ecosystem stability for kelp beds in urban environments By Simon E Reeves November 2017 Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy Institute for Marine and Antarctic Studies I DECLARATIONS This declaration certifies that: (i) This thesis contains no material that has been accepted for a degree or diploma by the University or any other institution. (ii) The work contained in this thesis, except where otherwise acknowledged, is the result of my own investigations. (iii) Due acknowledgement has been made in the text to all other material used (iv) The thesis is less than 100,000 words in length, exclusive of tables, maps, bibliographies and appendices. Signed: (Simon Reeves) Date: 1/12/2017 Statement of authority of access This thesis may be available for loan and limited copying in accordance with the Copyright Act 1968. Signed: (Simon Reeves) Date: 1/12/2017 II 20/7/18 ABSTRACT Ecologists have long been interested in determining the role biotic relationships play in natural systems. Even Darwin envisioned natural systems as "bound together by a web of complex relations”, noting how “complex and unexpected are the checks and relations between organic beings” (On the Origin of Species, 1859, pp 81-83). Any event or phenomenon that alters the implicit balance in the web of interactions, to any degree, can potentially facilitate a re-organisation in structure that can lead to a wholescale change to the stability of a natural system. As a result of the increasing diversity and intensity of anthropogenic stressors on ecosystems, previously well-understood biotic interactions and emergent ecological functions are being altered, requiring a reappraisal of their effects.
    [Show full text]
  • SDSU Template, Version 11.1
    THE EFFECTS OF IRRADIANCE IN DETERMINING THE VERTICAL DISTRIBUTION OF ELK KELP PELAGOPHYCUS PORRA _______________ A Thesis Presented to the Faculty of San Diego State University _______________ In Partial Fulfillment of the Requirements for the Degree Master of Science in Biology _______________ by Stacie Michelle Fejtek Fall 2008 SAN DIEGO STATE UNIVERSITY The Undersigned Faculty Committee Approves the Thesis of Stacie Michelle Fejtek: The Effects of Irradiance in Determining the Vertical Distribution of Elk Kelp, Pelagophycus porra _____________________________________________ Matthew S. Edwards, Chair Department of Biology _____________________________________________ Todd W. Anderson Department of Biology _____________________________________________ Douglas A. Stow Department of Geography ______________________________ Approval Date iii Copyright © 2008 by Stacie Michelle Fejtek All Rights Reserved iv DEDICATION This thesis is dedicated to my family and friends who have encouraged and supported me through the trials and challenges that accompany such an undertaking. A special thanks to Colby Smith who believed in me even when I didn’t believe in myself. v “Whatever you are be a good one” -Abraham Lincoln vi ABSTRACT OF THE THESIS The Effects of Irradiance in Determining the Vertical Distribution of Elk Kelp, Pelagophycus porra by Stacie Michelle Fejtek Master of Science in Biology San Diego State University, 2008 Elk Kelp, Pelagophycus porra, is commonly observed in deep (20-30 m) water along the outer edge of Giant Kelp, Macrocystis pyrifera, beds in southern California, USA and northern Baja California, MEX, but rarely occurs in shallower water or within beds of M. pyrifera. Due to the nature of P. porra’s heteromorphic life history that alternates between a macroscopic diploid sporophyte and a microscopic haploid gametophyte, investigations of both life history stages were needed to understand P.
    [Show full text]
  • Macrocystis Pyrifera: Interpopulation Comparisons and Temporal Variability
    MARINE ECOLOGY PROGRESS SERIES Published December 15 Mar. Ecol. Prog. Ser. Copper toxicity to microscopic stages of giant kelp Macrocystis pyrifera: interpopulation comparisons and temporal variability ' Institute of Marine Sciences, University of California, Santa Cruz. California 95064, USA Marine Pollution Studies Laboratory, California Department of Fish and Game, Coast Route 1, Granite Canyon, Monterey, California 93940, USA* ABSTRACT: Experiments were conducted to evaluate temporal and geographic variation in sensitivity of microscopic stages of giant kelp Macrocystis pyrifera to copper. Spores from kelp sporophylls collected from different locations and at different times of the year were exposed to series of copper concentrations following a standard toxicity test procedure. After 48 h static exposures, toxicity was determined by measuring 2 test endpoints: germination success and growth of germination tubes. The sensitivity of these endpoints to copper was also compared with the sensitivity of longer-term reproduc- tive endpoints: sporophyte production and sporophyte growth. No significant differences in response to copper were found among spores from different collection sites. Variability between 4 tests conducted quarterly throughout the year was greater than that between 3 tests done consecutively within 1 mo, indicating temporal variability in response to copper. Long-term reproductive endpoints were more sensitive to copper than were short-term vegetative endpoints, with No Observed Effect Concentrations of < 10 pg 1-' for sporophyte production, 10 yg 1-I for sporophyte growth, 10 yg 1-' for germ-tube growth, and 50 yg 1-I for germination inhibition. INTRODUCTION ductive failure, or growth of sensitive life stages (Bay et al. 1983, Lussier et al. 1985, ASTM 1987, Dinnel et al.
    [Show full text]
  • Marine Ecology Progress Series 483:117
    Vol. 483: 117–131, 2013 MARINE ECOLOGY PROGRESS SERIES Published May 30 doi: 10.3354/meps10261 Mar Ecol Prog Ser Variation in the morphology, reproduction and development of the habitat-forming kelp Ecklonia radiata with changing temperature and nutrients Christopher J. T. Mabin1,*, Paul E. Gribben2, Andrew Fischer1, Jeffrey T. Wright1 1National Centre for Marine Conservation and Resource Sustainability (NCMCRS), Australian Maritime College, University of Tasmania, Launceston, Tasmania 7250, Australia 2Biodiversity Research Group, Climate Change Cluster, University of Technology Sydney, Sydney, New South Wales 2007, Australia ABSTRACT: Increasing ocean temperatures are a threat to kelp forests in several regions of the world. In this study, we examined how changes in ocean temperature and associated nitrate concentrations driven by the strengthening of the East Australian Current (EAC) will influence the morphology, reproduction and development of the widespread kelp Ecklonia radiata in south- eastern Australia. E. radiata morphology and reproduction were examined at sites in New South Wales (NSW) and Tasmania, where sea surface temperature differs by ~5°C, and a laboratory experiment was conducted to test the interactive effects of temperature and nutrients on E. radiata development. E. radiata size and amount of reproductive tissue were generally greater in the cooler waters of Tasmania compared to NSW. Importantly, one morphological trait (lamina length) was a strong predictor of the amount of reproductive tissue, suggesting that morphological changes in response to increased temperature may influence reproductive capacity in E. radiata. Growth of gametophytes was optimum between 15 and 22°C and decreased by >50% above 22°C. Microscopic sporophytes were also largest between 15 and 22°C, but no sporophytes developed above 22°C, highlighting a potentially critical upper temperature threshold for E.
    [Show full text]
  • Rock Lobster Hab Itat Assessment Figure 20. Nine Mile Reef Video
    36 Rock Lobster Habitat Assessment Figure 20. Nine Mile Reef video survey sites (see Table 4 for biota codes). a. NMR01a low profile reef, sessile invertebrates. d. NMR03a low profile reef, sessile invertebrates. b. NMR02a low profile reef, sessile invertebrates. e. NMR05a high profile reef, sessile invertebrates. c. NMR03a low profile reef, sessile invertebrates. f. NMR06a low profile reef, sessile invertebrates. Rock Lobster Habitat Assessment 37 g. NMR06a low profile reef, sessile invertebrates. i. NMR09a low profile reef, sessile invertebrates. h. NMR08a High profile reef, sessile j. NMR09a low profile reef. invertebrates. Figure 21. Nine Mile Reef video still images. Rock Lobster Habitat Assessment 38 Rock Lobster Habitat Assessment Figure 22. Torquay and Ocean Grove (western area) video survey sites (see Table 4 for biota codes). 39 40 Rock Lobster Habitat Assessment Figure 23. Torquay and Ocean Grove (eastern area) video survey sites (see Table 4 for biota codes). a. OGT05a low profile reef, sessile invertebrates. d. OGT12a patchy low profile reef, sessile invertebrates / E. radiata b. OGT06a patchy low profile reef. e. OGT16a low profile reef, E. radiata / Cystophora spp. c. OGT11a high profile reef, E. radiata. F. OGT17a sediment, A. antarctica. Rock Lobster Habitat Assessment 41 g. OGT18a patchy low profile reef, Cystophora j. OGT24a patchy low profile reef, sessile spp. invertebrates (Butterfly perch). h. OGT22a low profile reef, E. radiata / Cystophora k. OGT27a patchy low profile reef ‐ cobble. spp. i. OGT23a low profile reef, E. radiata. l. OGT30a patchy low profile reef, E. radiata. Rock Lobster Habitat Assessment 42 m. OGT32a low profile reef, Cystophora spp. p.
    [Show full text]
  • Cultivating the Macroalgal Holobiont: Effects of Integrated Multi-Trophic Aquaculture on the Microbiome of Ulva Rigida (Chlorophyta)
    fmars-07-00052 February 10, 2020 Time: 15:0 # 1 ORIGINAL RESEARCH published: 12 February 2020 doi: 10.3389/fmars.2020.00052 Cultivating the Macroalgal Holobiont: Effects of Integrated Multi-Trophic Aquaculture on the Microbiome of Ulva rigida (Chlorophyta) Gianmaria Califano1, Michiel Kwantes1, Maria Helena Abreu2, Rodrigo Costa3,4,5 and Thomas Wichard1,6* 1 Institute for Inorganic and Analytical Chemistry, Friedrich Schiller University Jena, Jena, Germany, 2 ALGAplus Lda, Ílhavo, Portugal, 3 Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal, 4 Centre of Marine Sciences, University of Algarve, Faro, Portugal, 5 Lawrence Berkeley National Laboratory, U.S. Department of Energy Joint Genome Institute, University of California, Berkeley, Berkeley, CA, United States, 6 Jena School for Microbial Communication, Jena, Germany Ulva is a ubiquitous macroalgal genus of commercial interest. Integrated Multi-Trophic Aquaculture (IMTA) systems promise large-scale production of macroalgae due to Edited by: their high productivity and environmental sustainability. Complex host–microbiome Bernardo Antonio Perez Da Gama, interactions play a decisive role in macroalgal development, especially in Ulva spp. Universidade Federal Fluminense, due to algal growth- and morphogenesis-promoting factors released by associated Brazil bacteria. However, our current understanding of the microbial community assembly and Reviewed by: Alejandro H. Buschmann, structure in cultivated macroalgae is scant. We aimed to determine (i) to what extent University of Los Lagos, Chile IMTA settings influence the microbiome associated with U. rigida and its rearing water, (ii) Henrique Fragoso Santos, to explore the dynamics of beneficial microbes to algal growth and development under Universidade Federal Fluminense, Brazil IMTA settings, and (iii) to improve current knowledge of host–microbiome interactions.
    [Show full text]
  • Safety Assessment of Brown Algae-Derived Ingredients As Used in Cosmetics
    Safety Assessment of Brown Algae-Derived Ingredients as Used in Cosmetics Status: Draft Report for Panel Review Release Date: August 29, 2018 Panel Meeting Date: September 24-25, 2018 The 2018 Cosmetic Ingredient Review Expert Panel members are: Chair, Wilma F. Bergfeld, M.D., F.A.C.P.; Donald V. Belsito, M.D.; Ronald A. Hill, Ph.D.; Curtis D. Klaassen, Ph.D.; Daniel C. Liebler, Ph.D.; James G. Marks, Jr., M.D.; Ronald C. Shank, Ph.D.; Thomas J. Slaga, Ph.D.; and Paul W. Snyder, D.V.M., Ph.D. The CIR Executive Director is Bart Heldreth, Ph.D. This report was prepared by Lillian C. Becker, former Scientific Analyst/Writer and Priya Cherian, Scientific Analyst/Writer. © Cosmetic Ingredient Review 1620 L Street, NW, Suite 1200 ♢ Washington, DC 20036-4702 ♢ ph 202.331.0651 ♢ fax 202.331.0088 [email protected] Distributed for Comment Only -- Do Not Cite or Quote Commitment & Credibility since 1976 Memorandum To: CIR Expert Panel Members and Liaisons From: Priya Cherian, Scientific Analyst/Writer Date: August 29, 2018 Subject: Safety Assessment of Brown Algae as Used in Cosmetics Enclosed is the Draft Report of 83 brown algae-derived ingredients as used in cosmetics. (It is identified as broalg092018rep in this pdf.) This is the first time the Panel is reviewing this document. The ingredients in this review are extracts, powders, juices, or waters derived from one or multiple species of brown algae. Information received from the Personal Care Products Council (Council) are attached: • use concentration data of brown algae and algae-derived ingredients (broalg092018data1, broalg092018data2, broalg092018data3); • Information regarding hydrolyzed fucoidan extracted from Laminaria digitata has been included in the report.
    [Show full text]
  • Marine Macroalgal Biodiversity of Northern Madagascar: Morpho‑Genetic Systematics and Implications of Anthropic Impacts for Conservation
    Biodiversity and Conservation https://doi.org/10.1007/s10531-021-02156-0 ORIGINAL PAPER Marine macroalgal biodiversity of northern Madagascar: morpho‑genetic systematics and implications of anthropic impacts for conservation Christophe Vieira1,2 · Antoine De Ramon N’Yeurt3 · Faravavy A. Rasoamanendrika4 · Sofe D’Hondt2 · Lan‑Anh Thi Tran2,5 · Didier Van den Spiegel6 · Hiroshi Kawai1 · Olivier De Clerck2 Received: 24 September 2020 / Revised: 29 January 2021 / Accepted: 9 March 2021 © The Author(s), under exclusive licence to Springer Nature B.V. 2021 Abstract A foristic survey of the marine algal biodiversity of Antsiranana Bay, northern Madagas- car, was conducted during November 2018. This represents the frst inventory encompass- ing the three major macroalgal classes (Phaeophyceae, Florideophyceae and Ulvophyceae) for the little-known Malagasy marine fora. Combining morphological and DNA-based approaches, we report from our collection a total of 110 species from northern Madagas- car, including 30 species of Phaeophyceae, 50 Florideophyceae and 30 Ulvophyceae. Bar- coding of the chloroplast-encoded rbcL gene was used for the three algal classes, in addi- tion to tufA for the Ulvophyceae. This study signifcantly increases our knowledge of the Malagasy marine biodiversity while augmenting the rbcL and tufA algal reference libraries for DNA barcoding. These eforts resulted in a total of 72 new species records for Mada- gascar. Combining our own data with the literature, we also provide an updated catalogue of 442 taxa of marine benthic
    [Show full text]
  • Effect of Environmental History on the Habitat-Forming Kelp Macrocystis
    www.nature.com/scientificreports OPEN Efect of environmental history on the habitat‑forming kelp Macrocystis pyrifera responses to ocean acidifcation and warming: a physiological and molecular approach Pamela A. Fernández1*, Jorge M. Navarro2, Carolina Camus1, Rodrigo Torres3 & Alejandro H. Buschmann1 The capacity of marine organisms to adapt and/or acclimate to climate change might difer among distinct populations, depending on their local environmental history and phenotypic plasticity. Kelp forests create some of the most productive habitats in the world, but globally, many populations have been negatively impacted by multiple anthropogenic stressors. Here, we compare the physiological and molecular responses to ocean acidifcation (OA) and warming (OW) of two populations of the giant kelp Macrocystis pyrifera from distinct upwelling conditions (weak vs strong). Using laboratory mesocosm experiments, we found that juvenile Macrocystis sporophyte responses to OW and OA did not difer among populations: elevated temperature reduced growth while OA had no efect on growth − and photosynthesis. However, we observed higher growth rates and NO3 assimilation, and enhanced − expression of metabolic‑genes involved in the NO3 and CO2 assimilation in individuals from the strong upwelling site. Our results suggest that despite no inter‑population diferences in response to OA and − OW, intrinsic diferences among populations might be related to their natural variability in CO2, NO3 and seawater temperatures driven by coastal upwelling. Further work including additional populations and fuctuating climate change conditions rather than static values are needed to precisely determine how natural variability in environmental conditions might infuence a species’ response to climate change. Anthropogenic climate change, such as global warming and ocean acidifcation (OA) are altering the structure and functioning of terrestrial and marine ecosystems, causing shifs in the distribution and relative abundance of species1–4.
    [Show full text]
  • Biomass Rather Than Growth Rate Determines Variation in Net Primary Production by Giant Kelp
    Ecology, 89(9), 2008, pp. 2493–2505 Ó 2008 by the Ecological Society of America BIOMASS RATHER THAN GROWTH RATE DETERMINES VARIATION IN NET PRIMARY PRODUCTION BY GIANT KELP 1,3 2 2 DANIEL C. REED, ANDREW RASSWEILER, AND KATIE K. ARKEMA 1Marine Science Institute, University of California, Santa Barbara, California 93111 USA 2Department of Ecology, Evolution, and Marine Biology, University of California, Santa Barbara, California 93111 USA Abstract. Net primary production (NPP) is influenced by disturbance-driven fluctuations in foliar standing crop (FSC) and resource-driven fluctuations in rates of recruitment and growth, yet most studies of NPP have focused primarily on factors influencing growth. We quantified NPP, FSC, recruitment, and growth rate for the giant kelp, Macrocystis pyrifera,at three kelp forests in southern California, USA, over a 54-month period and determined the relative roles of FSC, recruitment, and growth rate in contributing to variation in annual NPP. Net primary production averaged between 0.42 and 2.38 kg dry massÁmÀ2ÁyrÀ1 at the three sites. The initial FSC present at the beginning of the growth year and the recruitment of new plants during the year explained 63% and 21% of the interannual variation observed in NPP, respectively. The previous year’s NPP and disturbance from waves collectively accounted for 80% of the interannual variation in initial FSC. No correlation was found between annual growth rate (i.e., the amount of new kelp mass produced per unit of existing kelp mass) and annual NPP (i.e., the amount of new kelp mass produced per unit area of ocean bottom), largely because annual growth rate was consistent compared to initial FSC and recruitment, which fluctuated greatly among years and sites.
    [Show full text]
  • Molecular Phylogeography and Climate Change Biology of the Invasive Green Marine Macroalgae Caulerpa Taxifolia and Caulerpa Cylindracea in Australia
    Molecular phylogeography and climate change biology of the invasive green marine macroalgae Caulerpa taxifolia and Caulerpa cylindracea in Australia Submitted by William Maxwell Grant BSc (Hons) Thesis submitted in total fulfillment of the requirements for the degree of Doctor of Philosophy Department of Ecology and Environmental Sciences School of Biology Faculty of Science The University of Adelaide Adelaide, South Australia 5005 Australia February 2015 1 Table of Contents Acknowledgments 4 Thesis Summary 6 Thesis Declaration 9 Chapter One: Thesis Introduction Introduction 11 Study Aims 17 Chapter Two: Molecular Ecology of Caulerpa taxifolia and Caulerpa cylindracea : a review Statement of Authorship 20 Caulerpa taxifolia 21 Molecular studies on Caulerpa taxifolia 23 Caulerpa cylindracea 33 Molecular studies on Caulerpa cylindracea 35 Conclusion 37 Chapter Three: Phylogeography of the invasive marine green macroalga Caulerpa taxifolia (M. Vahl) C.Agardh in Australian waters: a next generation sequencing approach to marker discovery Statement of Authorship 43 Abstract 44 Introduction 45 Materials and Methods: 49 Results: 56 Discussion 66 Chapter 4: Phylogeography of the invasive marine green macroalga Caulerpa cylindracea Sonder in Australia. Statement of Authorship 74 2 Abstract 75 Introduction 76 Materials and Methods: 79 Results 82 Discussion 88 Chapter 5: The effect of climate change experiments on DNA, RNA, and protein concentrations, and protein profiles native and invasive Caulerpa spp. Statement of Authorship Statement of Authorship 92 Abstract 93 Introduction 94 Materials and Methods: 97 Results: 99 Discussion 108 Chapter 6: General Discussion General discussion 114 References 122 3 Acknowledgments I would like to thank my supervisors, Dr Fred Gurgel, Dr Marty Deveney, and Assoc.
    [Show full text]
  • Natural Products of Marine Macroalgae from South Eastern Australia, with Emphasis on the Port Phillip Bay and Heads Regions of Victoria
    marine drugs Review Natural Products of Marine Macroalgae from South Eastern Australia, with Emphasis on the Port Phillip Bay and Heads Regions of Victoria James Lever 1 , Robert Brkljaˇca 1,2 , Gerald Kraft 3,4 and Sylvia Urban 1,* 1 School of Science (Applied Chemistry and Environmental Science), RMIT University, GPO Box 2476V Melbourne, VIC 3001, Australia; [email protected] (J.L.); [email protected] (R.B.) 2 Monash Biomedical Imaging, Monash University, Clayton, VIC 3168, Australia 3 School of Biosciences, University of Melbourne, Parkville, Victoria 3010, Australia; [email protected] 4 Tasmanian Herbarium, College Road, Sandy Bay, Tasmania 7015, Australia * Correspondence: [email protected] Received: 29 January 2020; Accepted: 26 February 2020; Published: 28 February 2020 Abstract: Marine macroalgae occurring in the south eastern region of Victoria, Australia, consisting of Port Phillip Bay and the heads entering the bay, is the focus of this review. This area is home to approximately 200 different species of macroalgae, representing the three major phyla of the green algae (Chlorophyta), brown algae (Ochrophyta) and the red algae (Rhodophyta), respectively. Over almost 50 years, the species of macroalgae associated and occurring within this area have resulted in the identification of a number of different types of secondary metabolites including terpenoids, sterols/steroids, phenolic acids, phenols, lipids/polyenes, pheromones, xanthophylls and phloroglucinols. Many of these compounds have subsequently displayed a variety of bioactivities. A systematic description of the compound classes and their associated bioactivities from marine macroalgae found within this region is presented. Keywords: marine macroalgae; bioactivity; secondary metabolites 1.
    [Show full text]