Variation in clonal structure in an eelgrass (Zostera marina) meadow on the Pacific coast of Canada

1992 ◽  
Vol 70 (3) ◽  
pp. 653-657 ◽  
Author(s):  
Paul G. Harrison ◽  
Cynthia Durance
Keyword(s):  
Zostera Marina ◽  
Clonal Diversity ◽  
Clonal Plant ◽  
Shoot Density ◽  
Banding Patterns ◽  
Original Population ◽  
Drainage Patterns ◽  
The Pacific ◽  
Microgeographic Variation ◽  
A Site

The seagrass Zostera marina L. was studied in southwestern British Columbia at a site where habitat quality has been altered by construction of a port. Morphology, shoot density, and electrophoretic banding patterns for eight enzyme systems were compared in plants from locations that represented the center of the original population (main), a marginal habitat colonized by seedlings, a remnant isolated by changes in drainage patterns, and the subtidal edge of the main bed (deep). Compared with the original population, both the colony and remnant populations had lower shoot densities and shorter shoots. The mean number of banding patterns was lower at the colony and deep locations than at the main location. Clonal diversity was lowest at the main and deep locations. As expected, the colony population shared no clones with the original population. The absence of shared clones in the remnant and original populations suggests that sexual reproduction and seedling establishment are more important in the dynamics of perennial eelgrass populations than is generally believed. Electrophoretically the plants at the seaward margin of the site were the most distinct and uniform; their relation to the other plants is unknown. Key words: clonal plant, electrophoresis, microgeographic variation, population genetic structure, Zostera marina.

MONARCHS, TRAVELLERS AND EMPIRE IN THE PACIFIC'S AGE OF REVOLUTIONS

2020 ◽  
Vol 30 ◽  
pp. 77-96
Author(s):  
Sujit Sivasundaram
Keyword(s):  
Pacific Islanders ◽  
Modern World ◽  
Global History ◽  
The Past ◽  
The Pacific ◽  
Cultural Terms ◽  
The Pacific Ocean ◽  
Definition Of ◽  
The Uk ◽  
A Site

AbstractThe Pacific has often been invisible in global histories written in the UK. Yet it has consistently been a site for contemplating the past and the future, even among Britons cast on its shores. In this lecture, I reconsider a critical moment of globalisation and empire, the ‘age of revolutions’ at the end of the eighteenth century and the start of the nineteenth century, by journeying with European voyagers to the Pacific Ocean. The lecture will point to what this age meant for Pacific islanders, in social, political and cultural terms. It works with a definition of the Pacific's age of revolutions as a surge of indigeneity met by a counter-revolutionary imperialism. What was involved in undertaking a European voyage changed in this era, even as one important expedition was interrupted by news from revolutionary Europe. Yet more fundamentally vocabularies and practices of monarchy were consolidated by islanders across the Pacific. This was followed by the outworkings of counter-revolutionary imperialism through agreements of alliance and alleged cessation. Such an argument allows me, for instance, to place the 1806 wreck of the Port-au-Prince within the Pacific's age of revolutions. This was an English ship used to raid French and Spanish targets in the Pacific, but which was stripped of its guns, iron, gunpowder and carronades by Tongans. To chart the trajectory from revolution and islander agency on to violence and empire is to appreciate the unsettled paths that gave rise to our modern world. This view foregrounds people who inhabited and travelled through the earth's oceanic frontiers. It is a global history from a specific place in the oceanic south, on the opposite side of the planet to Europe.

scholarly journals Megafauna of the UKSRL exploration contract area and eastern Clarion-Clipperton Zone in the Pacific Ocean: Annelida, Arthropoda, Bryozoa, Chordata, Ctenophora, Mollusca

2017 ◽  
Vol 5 ◽  
Author(s):  
Diva Amon ◽  
Amanda Ziegler ◽  
Jeffrey Drazen ◽  
Andrei Grischenko ◽  
Astrid Leitner ◽  
...  
Keyword(s):  
Pacific Ocean ◽  
Autonomous Underwater Vehicle ◽  
Remotely Operated Vehicle ◽  
Molecular Barcoding ◽  
Polymetallic Nodule ◽  
The Pacific ◽  
Biological Studies ◽  
Threatened Habitat ◽  
The Uk ◽  
A Site

There is growing interest in mining polymetallic nodules from the abyssal Clarion-Clipperton Zone (CCZ) in the tropical Pacific Ocean. Despite having been the focus of environmental studies for decades, the benthic megafauna of the CCZ remain poorly known. To predict and manage the environmental impacts of mining in the CCZ, baseline knowledge of the megafauna is essential. The ABYSSLINE Project has conducted benthic biological baseline surveys in the UK Seabed Resources Ltd polymetallic-nodule exploration contract area (UK-1). Prior to ABYSSLINE research cruises in 2013 and 2015, no biological studies had been done in this area of the eastern CCZ. Using a Remotely Operated Vehicle and Autonomous Underwater Vehicle (as well as several other pieces of equipment), the megafauna within the UK Seabed Resources Ltd exploration contract area (UK-1) and at a site ~250 km east of the UK-1 area were surveyed, allowing us to make the first estimates of megafaunal morphospecies richness from the imagery collected. Here, we present an atlas of the abyssal annelid, arthropod, bryozoan, chordate, ctenophore and molluscan megafauna observed and collected during the ABYSSLINE cruises to the UK-1 polymetallic-nodule exploration contract area in the CCZ. There appear to be at least 55 distinct morphospecies (8 Annelida, 12 Arthropoda, 4 Bryozoa, 22 Chordata, 5 Ctenophora, and 4 Mollusca) identified mostly by morphology but also using molecular barcoding for a limited number of animals that were collected. This atlas will aid the synthesis of megafaunal presence/absence data collected by contractors, scientists and other stakeholders undertaking work in the CCZ, ultimately helping to decipher the biogeography of the megafauna in this threatened habitat.

scholarly journals Toxicity of reduced nitrogen in eelgrass (Zostera marina) is highly dependent on shoot density and pH

Oecologia ◽  
2008 ◽  
Vol 158 (3) ◽  
pp. 411-419 ◽  
Author(s):  
T. van der Heide ◽  
A. J. P. Smolders ◽  
B. G. A. Rijkens ◽  
E. H. van Nes ◽  
M. M. van Katwijk ◽  
...  
Keyword(s):  
Zostera Marina ◽  
Shoot Density ◽  
Reduced Nitrogen

Clonal Diversity in Differently-Aged Populations of the Pseudo-Annual Clonal Plant Circaea lutetiana L.

Plant Biology ◽  
2000 ◽  
Vol 2 (6) ◽  
pp. 646-652 ◽  
Author(s):  
R. Verburg ◽  
J. Maas ◽  
H. J. During
Keyword(s):  
Clonal Diversity ◽  
Clonal Plant

scholarly journals A ‘MONTAGE OF MINORITIES’: HAWAI‘I TOURISM AND THE COMMODIFICATION OF RACIAL TOLERANCE, 1959–1978

2017 ◽  
Vol 60 (3) ◽  
pp. 817-842
Author(s):  
SARAH MILLER-DAVENPORT
Keyword(s):  
State Government ◽  
Tourism Industry ◽  
Us Foreign Policy ◽  
Social Harmony ◽  
Cultural Ideal ◽  
Racial Tolerance ◽  
Racial Experiences ◽  
The Pacific ◽  
A Site ◽  
Ethnic Festivals

AbstractThis article studies the Hawai‘i tourism industry's efforts to market Hawai‘i as a multi-cultural paradise where positive racial experiences could be bought and sold. With jet travel arriving in Hawai‘i the same year as statehood, the tourism industry, aided by the new state government, exploited Hawai‘i's newfound prominence, luring planeloads of American tourists who thronged its beaches, hotels, and cultural spectacles. Tourism helped turn racial tolerance into a saleable, if intangible, commodity. Marketers invited mainlanders to partake in the islands’ celebrated ‘Aloha Spirit’: an elusive vision of social harmony said to be the defining feature of the Hawai‘i vacation. By attending ethnic festivals, eating exotic food, and interacting with locals, visitors might even bring some Aloha Spirit home with them. Hawai‘i's society thus became not only a site of consumption, but an object of consumption itself. What such utopian ideas obscured was that the broader construction of Hawai‘i as a multi-cultural paradise was part of state efforts both to transform Hawai‘i's economy and to promote US influence in the Pacific. While the limited historiography on multi-culturalism situates its emergence in grassroots protest, this article argues for the elite origins of the multi-cultural ideal, which served the interests of both business and US foreign policy.

scholarly journals Habitat degradation of an eelgrass bed variably affects epifaunal biodiversity

2018 ◽  
Author(s):  
Francesca Rossi ◽  
Marie Pierrejean
Keyword(s):  
Species Diversity ◽  
Zostera Marina ◽  
Habitat Complexity ◽  
Photosynthetic Activity ◽  
Habitat Degradation ◽  
Shoot Density ◽  
Seagrass Habitat ◽  
Abiotic Stressors ◽  
Complex Patterns ◽  
Epifaunal Assemblages

Seagrass habitat complexity can determine species diversity and abundance, through, for instance, changes in the availability of microhabitats, refuge from predators or changes in the intensity and frequency of abiotic stressors. Human-related perturbations cause seagrass habitat degradation and, therefore, reduce its complexity, thereby affecting biodiversity. We have followed the epifaunal assemblages of a Zostera marina meadow and deliberately modified seagrass shoot density three times during a year to measure how epifaunal assemblages responded to habitat degradation and whether patterns of response were consistent through time. We have also measured in the laboratory how epifauna controlled epiphyte biomass, which could feedback on seagrass photosynthetic activity, growth and productivity, thereby changing its resilience to disturbances. Results have shown complex patterns, variable in time.

scholarly journals Habitat degradation of an eelgrass bed variably affects epifaunal biodiversity

2018 ◽  
Author(s):  
Francesca Rossi ◽  
Marie Pierrejean
Keyword(s):  
Species Diversity ◽  
Zostera Marina ◽  
Habitat Complexity ◽  
Photosynthetic Activity ◽  
Habitat Degradation ◽  
Shoot Density ◽  
Seagrass Habitat ◽  
Abiotic Stressors ◽  
Complex Patterns ◽  
Epifaunal Assemblages

Seagrass habitat complexity can determine species diversity and abundance, through, for instance, changes in the availability of microhabitats, refuge from predators or changes in the intensity and frequency of abiotic stressors. Human-related perturbations cause seagrass habitat degradation and, therefore, reduce its complexity, thereby affecting biodiversity. We have followed the epifaunal assemblages of a Zostera marina meadow and deliberately modified seagrass shoot density three times during a year to measure how epifaunal assemblages responded to habitat degradation and whether patterns of response were consistent through time. We have also measured in the laboratory how epifauna controlled epiphyte biomass, which could feedback on seagrass photosynthetic activity, growth and productivity, thereby changing its resilience to disturbances. Results have shown complex patterns, variable in time.

The persistence and stability of fish assemblages within eelgrass meadows (Zostera marina) on the Pacific coast of Canada

2013 ◽  
Vol 70 (5) ◽  
pp. 775-784 ◽  
Author(s):  
Clifford L.K. Robinson ◽  
Jennifer Yakimishyn
Keyword(s):  
Zostera Marina ◽  
Pacific Coast ◽  
Fish Assemblages ◽  
Time Lag ◽  
Critical Element ◽  
Short Time Series ◽  
Ecosystem Integrity ◽  
The Pacific ◽  
Temporal Turnover ◽  
Short Time

The persistence and stability of fish assemblages found in 34 eelgrass (Zostera marina) meadows along the British Columbia coast was examined from 2004 to 2011. Assemblage persistence (nontrending species composition) and assemblage stability (constancy in abundance over time) were assessed using a time-lag regression method that tests for temporal turnover within short time series. Overall, 85% of the fish assemblages persisted, and 80% of the assemblages exhibited stability in abundance over the 8-year study. Environmental conditions in 33 of 34 meadows did not change substantially over the 8 years, and the low interannual variability may have contributed to the high persistence and stability of the fish assemblages. The lack of temporal turnover in relatively undisturbed eelgrass fish assemblage properties is a critical element for effective monitoring of coastal ecosystem integrity.

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