DOCSLIB.ORG

Seagrass Foliage from the Maastrichtian Type Area (Maastrichtian, Danian, NE Belgium, SE Netherlands) ⁎ R.W.J.M

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Seagrass Foliage from the Maastrichtian Type Area (Maastrichtian, Danian, NE Belgium, SE Netherlands) ⁎ R.W.J.M Review of Palaeobotany and Palynology 144 (2007) 301–321 www.elsevier.com/locate/revpalbo Seagrass foliage from the Maastrichtian type area (Maastrichtian, Danian, NE Belgium, SE Netherlands) ⁎ R.W.J.M. van der Ham a, , J.H.A. van Konijnenburg-van Cittert a,b, L. Indeherberge c a Nationaal Herbarium Nederland, Leiden branch, P.O. Box 9514, 2300 RA Leiden, The Netherlands b Nationaal Natuurhistorisch Museum, P.O. Box 9517, 2300 RA Leiden, The Netherlands c Reuvoortweg 63, 3520 Zonhoven, Belgium Received 17 November 2005; received in revised form 3 July 2006; accepted 5 July 2006 Available online 18 September 2006 Abstract Seagrasses are the only angiosperms that have invaded the marine environment. Fossil seagrasses are rare and received only little attention to date. However, among the scarce plant fossils in the marine deposits of the Maastrichtian type area, remains of seagrasses are relatively common. The present paper provides a detailed description of the morphology and anatomy of the leaves. Maastrichtian and Danian material is considered here as a single species: Thalassotaenia debeyi gen. nov., sp. nov. Campanian material is assigned to Zosterites, but this is not necessarily a seagrass. Thalassotaenia includes the oldest anatomically preserved material of seagrass leaves. Comparison with extant seagrasses shows that there is not an easy match with any of the extant genera or families. Amphibolis and Thalassodendron (Cymodoceaceae) and Posidonia (Posidoniaceae) show the greatest resemblance. Possibly, Thalassotaenia represents the leaves of an ancestor of the Cymodoceaceae–Posidoniaceae (–Ruppiaceae) clade found in several phylogenetic analyses. Because Thalassotaenia also shows some features not found in extant seagrasses, it might also represent an extinct clade of seagrasses. © 2006 Elsevier B.V. All rights reserved. Keywords: seagrass leaves; Cymodoceaceae; Posidoniaceae; Thalassocharis; Maastrichtian 1. Introduction tidae (Monocotyledonae) having been recognised in a rbcL study by Les et al. (1997). Considerable monocot diver- Worldwide, seagrass communities are important eco- sification took place during the Early Cretaceous, and systems in relatively warm, shallow seas (Green and Short, seagrasses probably evolved from freshwater monocots 2003). They are well-known for their high biodiversity and during the Late Cretaceous (Janssen and Bremer, 2004). over the last decades there has been a lot of research into Fossil seagrasses are rare. The oldest record is from the many aspects of seagrass biology and ecology (e.g. Brasier, Early Campanian of the Netherlands: Thalassocharis 1975; Larkum et al., 1989, 2006). Seagrasses are the only mülleri (Debey, 1848; Pomel, 1849; Debey,1851), which angiosperms that have successfully invaded the marine represents the stem of a seagrass. Voigt and Domke (1955) environment. They make up an ecological, polyphyletic published an extensive paper on Thalassocharis bosquetii group rather than a single taxonomical, monophyletic Debey ex Miquel from the Late Maastrichtian of the group, three different clades within the subclass Alisma- Netherlands, in which they analysed anatomically pre- served stems and attached roots, considering these related ⁎ Corresponding author. Fax: +31 0 71 527 35 11. to those of the extant genus Cymodocea. A description of E-mail address: [email protected] (R.W.J.M. van der Ham). the leaves is lacking so far. They are always found detached 0034-6667/$ - see front matter © 2006 Elsevier B.V. All rights reserved. doi:10.1016/j.revpalbo.2006.07.008 302 R.W.J.M. van der Ham et al. / Review of Palaeobotany and Palynology 144 (2007) 301–321 and incomplete, without base and apex, represented by different parts of the Maastrichtian type area (Fig. 1) fragments mostly not longer than a few centimeters, and and originates from the Early Campanian to Early usually poorly preserved, showing only a faint imprint with Danian time interval (Fig. 2). indistinct venation. Recently, however, several leaf frag- Two Early Campanian specimens are from the Vaals ments with remarkable details were discovered by one of us Formation (Inoceramus lingua/Gonioteuthis quadrata (LI). These include isolated fragments in chert, showing Zone) of Hallembaye in the southwestern part of the venation, fiber strands and even cell patterns, as well as the area (Fig. 1: locality 1). remains of amassed fragments in chert suited for thin- A single Late Maastrichtian specimen is from the Lixhe sectioning. This material allows detailed description and I Member of the Gulpen Formation (Belemnitella junior statements about the affinity of the seagrass foliage from Zone) of Loën in the southwestern part (Fig. 1: locality 2), the Maastrichtian type area (NE Belgium, SE Netherlands). while all other Late Maastrichtian material is from several The present paper is part of the ongoing study of members of the Maastricht Formation (Belemnitella junior fossil plants from the Maastrichtian type area. Earlier Zone and Belemnella kasimiroviensis Zone) in both the papers dealt with conifers and associated fungi (Van der southwestern and the northeastern part of the area. The Ham and Dortangs, 2005, and references therein). material from the southwestern part (Fig. 1: localities 1, 3– 6) is from the fully marine facies of the Maastricht 2. Material, localities and stratigraphy Formation (Valkenburg to Meerssen Members), while specimens from the northeastern part (Fig. 1:localities8– The material studied (c. 200 specimens; see Section 20) originate from the Kunrade Chalk, which is the more 4. Systematics and descriptions) was collected in coastal facies of the Maastricht Formation (Fig. 2). The Fig. 1. Map of the Maastrichtian type area, showing the localities where Thalassotaenia debeyi has been collected: 1. Hallembaye, 2. Loën, 3. Sluizen, 4. Romontbos, 5. Zichen, 6. ENCI, 7. Geulhem, 8. boring XVI, 9. boring S.M. XIX, 10. Emma I, 11. Oranje Nassau III, 12. boring 634, 13. boring 1291, 14. Kunrade, 15. Winthagen, 16. Welterberg, 17. Daelhoeve, 18. Benzenrade, 19. Simpelveld, 20. Vetschau. Locality 1 (Hallembaye) also provided the material of Zosterites sp. R.W.J.M. van der Ham et al. / Review of Palaeobotany and Palynology 144 (2007) 301–321 303 Fig. 2. Stratigraphy of the Cretaceous deposits in the Maastrichtian type area, showing the origin of the material of Thalassotaenia debeyi (Gulpen and Maastricht Formations) and Zosterites sp. (Vaals Formation). See Jagt (1999) for further stratigraphical details. The dot at the level of the Lichtenberg Horizon represents the specimens from the residual chert deposit (′flint eluvium′) of Hallembaye (including the type material) as well as those from the Valkenburg Member, and the dot at the Gronsveld Member, besides those of the Gronsveld Member, also the specimens from the Kunrade Chalk. Besides the residual chert deposit derived from the top of the Lanaye Member and base of the Maastricht Formation (indicated in scheme as ′flint eluvium′), a younger residual chert deposit exists (not indicated in scheme) derived from a part of the Nekum Member. 304 R.W.J.M. van der Ham et al. / Review of Palaeobotany and Palynology 144 (2007) 301–321 Fig. 3. Selected specimens of Thalassotaenia debeyi, gen. et sp. nov., showing veins, alternating fiber strands and cross-veins. a–c. Kunrade Chalk, Emma I, a. JMS 52006 (see also Plate III, 3), b, c. JMS 52067 (see also Plate III, 1). d–e. Residual chert deposit (′flint eluvium′), Hallembaye, NHMM LI 451 and 452, respectively (part and counterpart; type material; see also Plate I, 3, 4); note adaxial and abaxial fiber strands close together in Fig. 3d, immediately right of the midrib. f–g. Kunrade Chalk, Benzenrade, f. JMS 52027 (see also Plate II, 2), g. JMS 52045. h. Nekum Member, residual chert deposit, Sluizen, NHMM LI 4606 (see also Plate I, 2). i. Early Danian part of Meerssen Member, Geulhem, NHMM RH 808. Bar=10 mm (a–e, g–i) or 20 mm (f ). R.W.J.M. van der Ham et al. / Review of Palaeobotany and Palynology 144 (2007) 301–321 305 anatomically preserved leaves were found in residual chert vein thicker than the others; stomata absent; hypoder- deposits (‘flint eluvium’), which originated by dissolution mis present. of the chalky matrix from the top of the Lanaye Member of Etymology: From Greek thalassa (sea) and tainia the Gulpen Formation and the base of the Maastricht (strap), referring to the shape of the leaves and the Formation (Hallembaye; Fig. 1: locality 1) and from the environment in which they grew. Nekum Member (Romontbos quarry and Sluizen; Fig. 1: Type: Thalassotaenia debeyi sp. nov. localities 3, 4). Affinity: Monocotyledonae, ?Cymodoceaceae/Posido- Early Danian fossils are from the uppermost part of niaceae (see: Section 6. Affinities). the Meerssen Member of the Maastricht Formation (E clay sensu Smit and Brinkhuis, 1996) of Geulhem Thalassotaenia debeyi Van der Ham et Van Konij- (Fig. 1: locality 7). nenburg-Van Cittert, sp. nov. (Fig. 3; Plates I, 2–4; II; The following abbreviations are used to denote the III; IV, 1–3; V, 1–3;) locations of the specimens: IRSNB: Institut royal des Sciences naturelles de Belgique, Brussels, Belgium; JMS: 1849 Abdrücke eines najadeenartigen Blattes — Debey, p. 285, 286 Jongmans collection, Nationaal Natuurhistorisch Muse- 1851 Najadeenblätter (Thalassocharis/Zosterites) — Debey, p. 568 um, Leiden, The Netherlands; MB.PB.: Museum für 1853 ? phyllitae monocotylei,1.— Miquel, p. 53 Naturkunde der Humboldt Universität, Berlin, Germany; 1853 non phyllitae monocotylei,2.— Miquel,
Load more

Recommended publications
  • Growth and Population Dynamics of Posidonia Oceanica on the S~Anishmediterranean Coast: Elucidatina Seacrrass Decline
    MARINE ECOLOGY PROGRESS SERIES Vol. 137: 203-213, 1996 Published June 27 Mar Ecol Prog Ser Growth and population dynamics of Posidonia oceanica on the S~anishMediterranean coast: elucidatina seacrrass decline Nuria ~arba'l*,Carlos M. ~uarte',Just cebrianl, Margarita E. ~allegos~, Birgit Olesen3, Kaj sand-~ensen~ 'Centre dlEstudis Avanqats de Blanes, C.S.I.C., Cami de Santa Barbara sin, E-17300 Blanes, Girona, Spain 'Departamento de Hidrobiologia, Universidad Autonoma Metropolitana- Iztapalapa, Michocan y Purisima, col. Vicentina, AP 55-535, 09340 Mexico D.F., Mexico 3Department of Plant Ecology, University of Aarhus, Nordlandsvej 68, DK-8240 Risskov. Denmark 'Freshwater Biological Laboratory. University of Copenhagen, 51 Helsingersgade, DK-3400 Hillered. Denmark ABSTRACT: The growth and population dynamics of Posidonia oceanica were examined in 29 mead- ows along 1000 km of the Spanish Mediterranean coast (from 36"46' to 42"22' N). oceanica devel- oped the densest meadows (1141 shoots m-') and the highest aboveground biomass (1400 g DW m") between 38 and 39"N. P. oceanica shoots produced, on average, 1 leaf every 47 d, though leaf forma- tion rates in the populations increased from north to south (range 5 7 to 8.9leaves shoot-' yr-'). P ocean- ica is a long-living seagrass, with shoots able to live for at least 30 yr P, oceanica recruited shoots at low rates (0.02 to 0.5 In units yr-l) which did not balance the mortality rates (0.06 to 0.5 In unlts yr.') found in most (57 %) of the meadows. If the present disturbance and rate of decline are maintained, shoot den- sity is predicted to decline by 50% over the coming 2 to 24 yr.
    [Show full text]
  • Global Seagrass Distribution and Diversity: a Bioregional Model ⁎ F
    Journal of Experimental Marine Biology and Ecology 350 (2007) 3–20 www.elsevier.com/locate/jembe Global seagrass distribution and diversity: A bioregional model ⁎ F. Short a, , T. Carruthers b, W. Dennison b, M. Waycott c a Department of Natural Resources, University of New Hampshire, Jackson Estuarine Laboratory, Durham, NH 03824, USA b Integration and Application Network, University of Maryland Center for Environmental Science, Cambridge, MD 21613, USA c School of Marine and Tropical Biology, James Cook University, Townsville, 4811 Queensland, Australia Received 1 February 2007; received in revised form 31 May 2007; accepted 4 June 2007 Abstract Seagrasses, marine flowering plants, are widely distributed along temperate and tropical coastlines of the world. Seagrasses have key ecological roles in coastal ecosystems and can form extensive meadows supporting high biodiversity. The global species diversity of seagrasses is low (b60 species), but species can have ranges that extend for thousands of kilometers of coastline. Seagrass bioregions are defined here, based on species assemblages, species distributional ranges, and tropical and temperate influences. Six global bioregions are presented: four temperate and two tropical. The temperate bioregions include the Temperate North Atlantic, the Temperate North Pacific, the Mediterranean, and the Temperate Southern Oceans. The Temperate North Atlantic has low seagrass diversity, the major species being Zostera marina, typically occurring in estuaries and lagoons. The Temperate North Pacific has high seagrass diversity with Zostera spp. in estuaries and lagoons as well as Phyllospadix spp. in the surf zone. The Mediterranean region has clear water with vast meadows of moderate diversity of both temperate and tropical seagrasses, dominated by deep-growing Posidonia oceanica.
    [Show full text]
  • Posidonia Paper.Docx
    Epiphyte accruel patterns and effects on Posidonia oceanica By Emily Hardison and Scott Borsum Abstract This study focuses on the relationship between Posidonia oceanica leaves and the epiphytes that live on those leaves at Stareso Research center in Calvi Bay, Corsica. We determine patterns of epiphyte accrual along Posidonia oceanica leaves for depths of 5m, 10m, 15m, and 20m and calculate the abundance of epiphytes across this depth range and the biomass of epiphytes in Posidonia oceanica bed at each depth, through in water measurements and characterizing epiphyte loads of samples brought onshore. We show that epiphytes aggregate in depth specific and leaf-side specific patterns along Posidonia leaves, cause degradation of live Posidonia tissue, and contribute a significant amount of biomass to Posidonia oceanica beds and detritus. We attempt to explain why certain patterns of epiphyte accrual are seen by determining that the convex side of the leaf most commonly faces up towards the sun. Introduction Posidonia oceanica is a protected endemic seagrass species in the Mediterranean Sea. This species is particularly interesting because of the large role it plays in maintaining a healthy and diverse Mediterranean ecosystem. It grows in vasts meadows and provides habitats, food, and nursery areas for a wide array of species (Boudouresque C. et al., 2006). Despite its energy expensive lifestyle, Posidonia is able to survive in the nutrient poor waters of the Mediterranean Sea (Lepoint, 2002). Posidonia is often inhabited by epiphytes. Previous research has shown that epiphyte load on Posidonia leaves has a negative relationship with depth (Lopez, 2012). Light attenuates with depth and can therefore become a limiting factor for primary producers, like Posidonia.
    [Show full text]
  • Morpho-Chronological Variations and Primary Production in Posidonia
    Morpho-chronological variations and primary production in Posidonia sea grass from Western Australia Gérard Pergent, Christine Pergent-Martini, Catherine Fernandez, Pasqualini Vanina, Diana Walker To cite this version: Gérard Pergent, Christine Pergent-Martini, Catherine Fernandez, Pasqualini Vanina, Diana Walker. Morpho-chronological variations and primary production in Posidonia sea grass from Western Aus- tralia. Journal of the Marine Biological Association of the United Kingdom, Cambridge University Press, 2004, 84 (5), pp.895-899. 10.1017/S0025315404010161h. hal-01768985 HAL Id: hal-01768985 https://hal.archives-ouvertes.fr/hal-01768985 Submitted on 17 Apr 2018 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. J. Mar. Biol. Ass. U.K. (2004), 84, 895^899 Printed in the United Kingdom Morpho-chronological variations and primary production in Posidonia sea grass from Western Australia P Ge¤rard Pergent* , Christine Pergent-Martini*, Catherine Fernandez*, O Vanina Pasqualini* and Diana Walker O *Equipe Ecosyste' mes Littoraux, Faculty of Sciences,
    [Show full text]
  • GENOME EVOLUTION in MONOCOTS a Dissertation
    GENOME EVOLUTION IN MONOCOTS A Dissertation Presented to The Faculty of the Graduate School At the University of Missouri In Partial Fulfillment Of the Requirements for the Degree Doctor of Philosophy By Kate L. Hertweck Dr. J. Chris Pires, Dissertation Advisor JULY 2011 The undersigned, appointed by the dean of the Graduate School, have examined the dissertation entitled GENOME EVOLUTION IN MONOCOTS Presented by Kate L. Hertweck A candidate for the degree of Doctor of Philosophy And hereby certify that, in their opinion, it is worthy of acceptance. Dr. J. Chris Pires Dr. Lori Eggert Dr. Candace Galen Dr. Rose‐Marie Muzika ACKNOWLEDGEMENTS I am indebted to many people for their assistance during the course of my graduate education. I would not have derived such a keen understanding of the learning process without the tutelage of Dr. Sandi Abell. Members of the Pires lab provided prolific support in improving lab techniques, computational analysis, greenhouse maintenance, and writing support. Team Monocot, including Dr. Mike Kinney, Dr. Roxi Steele, and Erica Wheeler were particularly helpful, but other lab members working on Brassicaceae (Dr. Zhiyong Xiong, Dr. Maqsood Rehman, Pat Edger, Tatiana Arias, Dustin Mayfield) all provided vital support as well. I am also grateful for the support of a high school student, Cady Anderson, and an undergraduate, Tori Docktor, for their assistance in laboratory procedures. Many people, scientist and otherwise, helped with field collections: Dr. Travis Columbus, Hester Bell, Doug and Judy McGoon, Julie Ketner, Katy Klymus, and William Alexander. Many thanks to Barb Sonderman for taking care of my greenhouse collection of many odd plants brought back from the field.
    [Show full text]
  • The Genus Ruppia L. (Ruppiaceae) in the Mediterranean Region: an Overview
    Aquatic Botany 124 (2015) 1–9 Contents lists available at ScienceDirect Aquatic Botany journal homepage: www.elsevier.com/locate/aquabot The genus Ruppia L. (Ruppiaceae) in the Mediterranean region: An overview Anna M. Mannino a,∗, M. Menéndez b, B. Obrador b, A. Sfriso c, L. Triest d a Department of Sciences and Biological Chemical and Pharmaceutical Technologies, Section of Botany and Plant Ecology, University of Palermo, Via Archirafi 38, 90123 Palermo, Italy b Department of Ecology, University of Barcelona, Av. Diagonal 643, 08028 Barcelona, Spain c Department of Environmental Sciences, Informatics & Statistics, University Ca’ Foscari of Venice, Calle Larga S. Marta, 2137 Venice, Italy d Research Group ‘Plant Biology and Nature Management’, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium article info abstract Article history: This paper reviews the current knowledge on the diversity, distribution and ecology of the genus Rup- Received 23 December 2013 pia L. in the Mediterranean region. The genus Ruppia, a cosmopolitan aquatic plant complex, is generally Received in revised form 17 February 2015 restricted to shallow waters such as coastal lagoons and brackish habitats characterized by fine sediments Accepted 19 February 2015 and high salinity fluctuations. In these habitats Ruppia meadows play an important structural and func- Available online 26 February 2015 tional role. Molecular analyses revealed the presence of 16 haplotypes in the Mediterranean region, one corresponding to Ruppia maritima L., and the others to various morphological forms of Ruppia cirrhosa Keywords: (Petagna) Grande, all together referred to as the “R. cirrhosa s.l. complex”, which also includes Ruppia Aquatic angiosperms Ruppia drepanensis Tineo.
    [Show full text]
  • Restoration of Seagrass Meadows in the Mediterranean Sea: a Critical Review of Effectiveness and Ethical Issues
    water Review Restoration of Seagrass Meadows in the Mediterranean Sea: A Critical Review of Effectiveness and Ethical Issues Charles-François Boudouresque 1,*, Aurélie Blanfuné 1,Gérard Pergent 2 and Thierry Thibaut 1 1 Aix-Marseille University and University of Toulon, MIO (Mediterranean Institute of Oceanography), CNRS, IRD, Campus of Luminy, 13009 Marseille, France; [email protected] (A.B.); [email protected] (T.T.) 2 Università di Corsica Pasquale Paoli, Fédération de Recherche Environnement et Societé, FRES 3041, Corti, 20250 Corsica, France; [email protected] * Correspondence: [email protected] Abstract: Some species of seagrasses (e.g., Zostera marina and Posidonia oceanica) have declined in the Mediterranean, at least locally. Others are progressing, helped by sea warming, such as Cymodocea nodosa and the non-native Halophila stipulacea. The decline of one seagrass can favor another seagrass. All in all, the decline of seagrasses could be less extensive and less general than claimed by some authors. Natural recolonization (cuttings and seedlings) has been more rapid and more widespread than was thought in the 20th century; however, it is sometimes insufficient, which justifies transplanting operations. Many techniques have been proposed to restore Mediterranean seagrass meadows. However, setting aside the short-term failure or half-success of experimental operations, long-term monitoring has usually been lacking, suggesting that possible failures were considered not worthy of a scientific paper. Many transplanting operations (e.g., P. oceanica) have been carried out at sites where the species had never previously been present. Replacing the natural Citation: Boudouresque, C.-F.; ecosystem (e.g., sandy bottoms, sublittoral reefs) with P.
    [Show full text]
  • On the Sea-Grasses in Japan (III)
    On the Sea-grasses in Japan (III). General Consideration on the Japanese Sea-grasses By Shigeru Niiki Received October 3, 1933 I. Characters of Sea-Grasses A. Shape B. Morphological Differences from the Allied Fresh Water Plants II. Distribution of Sea-Grasses A. General Distribution B. Sea-Grasses in the World C. On Non-Occurrence of Posidonia in Japan III. Floristic Consideration of Sea-Grasses in Japan A. Zosteraceae B. Cymodoceaceae C. Ilydrocaritaceae IV. Summary V. Literature There are eight genera of sea-grasses known in the world. Of these, with the exception of Posidonia, seven remaining genera represented by 15 species, are found in Japan. They have been described in my previous papers (9, 10 and 11). Among them the great majority of Zostera and Phyllospadix species are endemic, while Gym odocea, Diplanthera except one, and all species of the Hydrocaritaceae belong to the Indo-1\Ialay element. The morphological characters of sea-grasses together with their ecological and floristic distribution in general may now be considered. I. Characters of Sea-Grasses A. Shape The leaf is ribbon-like in form except in Halophila and the vegetative shoots grow all the year round except in the northern form of Zostera nana. The arrangement of leaves vary in different families; in the Hydro- 172 THE BOTANICAL MAGAZINE (vol. XLVIII,No. X67 caritaceae they are arranged on the upper and lower side of the rhizome and without axillant leaf on the branches except the rhizome of T halassia (11), while in all other families leaves are attached to the lateral sides of rhizome, and each branch is provided with an axillant leaf.
    [Show full text]
  • The Rise of Ruppia in Seagrass Beds: Changes in Coastal Environment and Research Needs
    In: Handbook on Environmental Quality ISBN: 978-1-60741-420-9 Editors: E. K. Drury, T. S. Pridgen, pp. - © 2009 Nova Science Publishers, Inc. Chapter 12 THE RISE OF RUPPIA IN SEAGRASS BEDS: CHANGES IN COASTAL ENVIRONMENT AND RESEARCH NEEDS Hyun Jung Cho*1, Patrick Biber*2 and Cristina Nica1 1 Department of Biology; Jackson State University; 1400 Lynch St., Jackson, MS 39217, USA 2 Department of Coastal Sciences; The University of Southern Mississippi; 703 East Beach Drive, Ocean Springs, MS 39564 ABSTRACT It is well known that the global seagrass beds have been declining due to combining effects of natural/anthropogenic disturbances. Restoration efforts have focused on revegetation of the lost seagrass species, which may well work in cases the seagrass loss is recent and the habitat quality has not been altered substantially. Recent studies in several estuaries in the U.S. report the similar change in the seagrass community structures: much of the habitats previously dominated by stable seagrasses (Thalassia testudinum and Syringodium filiforme in tropical and Zostera marina in temperate regions) are now replaced by Ruppia maritima, an opportunistic, pioneer species that is highly dependent on sexual reproduction. The relative increases of R. maritima in seagrass habitats indicate that: (1) the coastal environmental quality has been altered to be more conducive to this species; (2) the quality of environmental services that seagrass beds play also have been changed; and (3) strategies for seagrass restoration and habitat management need to be adjusted. Unlike Zostera or Thalassia, Ruppia maritima beds are known for their seasonal and annual fluctuations. The authors’ previous and on-going research and restoration efforts as well as literature reviews are presented to discuss the causes for and the potential impacts of this change in seagrass community on the coastal ecosystem and future restoration strategies.
    [Show full text]
  • Epiphyte Load on the Seagrass Posidonia Oceanica (L.) Delile Does
    SCIENTIA MARINA 72(3) September 2008, 503-510, Barcelona (Spain) ISSN: 0214-8358 Epiphyte load on the seagrass Posidonia oceanica (L.) Delile does not indicate anthropogenic nutrient loading in Cabrera Archipelago National Park (Balearic Islands, Western Mediterranean) JORGE TERRADOS and FRANCISCO JAVIER MEDINA PONS Instituto Mediterráneo de Estudios Avanzados (CSIC-UIB), C/ Miquel Marqués 21, 07190 Esporles, Mallorca, Spain. E-mail: [email protected] SUMMARY: The epiphyte load on the leaves of the seagrass Posidonia oceanica (L.) Delile was estimated at the end of summer in three sites and two depths (7 m and 17 m) of the Cabrera Archipelago National Park (Balearic Islands, Western Mediterranean) from 2004 to 2006 to evaluate if epiphyte load could be used as an indicator of anthropogenic nutrient loading in the shallow marine ecosystems of the park. Asymmetrical ANOVA was used to divide data variability into two components: the contrast between the site receiving direct anthropogenic inputs of nutrients and organic matter (Es Port) and the two control sites (Cala Santa María, Es Burri); and the variability between the control sites. The nitrogen concentra- tion in P. oceanica leaves was higher in Es Port than in Cala Santa María and Es Burri but only at 7 m depth. There was no difference between the epiphyte load on P. oceanica shoots in Es Port and the sites without inputs at both 7 m and 17 m. However, the epiphyte load in Es Burri was higher than that in Cala Santa María at both depths. The results show that the epiphyte load on P. oceanica shoots was not a sensitive indicator of anthropogenic nutrient and organic matter loading in Cabrera Archipelago National Park.
    [Show full text]
  • Monocotyledons, Posid
    Published in: Journal of Phycology (2007), vol. 4 ,iss. 2, pp. 208-218 Status: Postprint (Author’s version) FIELD MEASUREMENTS OF INORGANIC NITROGEN UPTAKE BY EPIFLORA COMPONENTS OF THE SEAGRASS POSIDONIA OCEANICA (MONOCOTYLEDONS, POSIDONIACEAE) Gilles Lepoint Laboratoire d'Océanologie, MARE Centre, Institut de Chimie, Bât. B6, Université de Liège, 4000 Liège, Belgique Julien Jacquemart MARE Centre, Algologie, Mycologie et Systématique Expérimentale, Bât. B22, Boulevard du Rectorat 27, 4000 Liège, Belgique Jean-Marie Bouquegneau Laboratoire d'Océanologie, MARE Centre, Institut de Chimie, Bât. B6, Université de Liège, 4000 Liège, Belgique Vincent Demoulin MARE Centre, Algologie, Mycologie et Systématique Expérimentale, Bât. B22, Boulevard du Rectorat 27, 4000 Liège, Belgique and Sylvie Gobert Laboratoire d'Océanologie, MARE Centre, Institut de Chimie, Bât. B6, Université de Liège, 4000 Liège, Belgique Abstract Crustose corallines, crustose and erect brown algae, and sessile animals are major components of the epiphytic community of the Mediterranean seagrass Posidonia oceanica (L.) Delile. Production, biomass, and specific composition of this epiphyte-seagrass association are impacted by anthropogenic increase of nutrient load in this oligotrophic area. In this context, nitrogen uptake by P. oceanica and its epiflora was measured using the isotope 15 N at a 10 m depth in the Revellata Bay (Corsica, Mediterranean Sea). Epiflora components showed various seasonal patterns of biomass and abundance. The epiphytic brown algae appeared at the end of spring, later than the crustose corallines, and after the nitrate peak in the bay. Because of their later development in the season, epiphytic brown algae mostly rely on ammonium for their N needs. We hypothesize that the temporal succession of epiphytic organisms plays a crucial role in the N dynamics of this community under natural conditions.
    [Show full text]
  • Posidonia Australis Complex Seagrass Meadows Draft Description
    1 POSIDONIA AUSTRALIS COMPLEX SEAGRASS MEADOWS DRAFT 2 DESCRIPTION 3 4 Draft Description 5 The ecological community consists of the assemblage of plants, animals and micro-organisms 6 associated with seagrass meadows dominated by species from the Posidonia australis 7 complex and occurs mostly in temperate regions of Australia. The ecological community is the 8 climax community of a successional process that occurs over decades to centuries (Kendrick et 9 al, 2008). 10 11 Name of the ecological community 12 The ecological community was nominated as Posidonia australis seagrass beds or Posidonia 13 dominated seagrass meadows. The Threatened Species Scientific Committee recommended 14 that the ecological community be assessed as Posidonia seagrass meadows and it was placed 15 on the 2011 Finalised Priority Assessment List (FPAL) by the Minister for the Environment, 16 with an assessment period ending in December 2013. 17 Further consideration of the definition of this marine ecological community, including an 18 expert workshop, resulted in a focus on the species of the Posidonia australis complex. The 19 P. australis complex is one of two distinct groups of Australian Posidonia species; the other 20 being the P. ostenfeldii complex1. The two groups can be separated on the basis of their leaf 21 and rhizome characteristics but also their ecological characteristics. The three species of the 22 P. australis complex (P. australis; P. angustifolia; and P. sinuosa) are the meadow forming 23 species of the Posidonia genus (Cambridge and Kuo, 1979). It is therefore recommended that 24 the name of the ecological community be Posidonia australis complex seagrass meadows 25 (hereafter referred to as ‘the ecological community’).
    [Show full text]