Morphology and spatial distribution of alien sea-rockets (Cakile spp.) on South Australian and Western Canadian beaches

2004 ◽  
Vol 52 (2) ◽  
pp. 175 ◽  
Author(s):  
Timothy W. D. Cody ◽  
Martin L. Cody

Sea-rockets (Cakile spp., Brassicaceae) are annual plants of sandy beaches. Cakile edentula (Bigel.) Hook. is native to the eastern coast of North America, C. maritima Scop. to western Europe and the Mediterranean basin. The two species differ in several morphological features, including leaf form, fruits and petal size. Both are long-established aliens on beaches in western Canada and southern Australia, at sites where we examined their morphological and distributional attributes. The two Cakile species co-occur at Pachina Beach, British Columbia, Canada, with C. edentula more common and widely distributed over broader range of beach elevations and C. maritima restricted to the upper beach. Although a few putative hybrids occur, the species are morphologically quite distinct. In contrast, on Westlake Shores beach, South Australia, Cakile is at least in part perennial, with widely variable morphologies, and the taxon is not separable into two morphologically distinct entities. Species boundaries have blurred apparently because of introgression. Factors that may have lead to this contrasting situation in South Australia are discussed.

2018 ◽  
Vol 6 (2) ◽  
pp. 91-103
Author(s):  
Ágnes Vass

AbstractPolicy towards Hungarians living in neighbouring countries has been a central issue for Hungarian governments, yet Hungarian diaspora living mainly in Western Europe and North America have received very little attention. This has changed after the 2010 landslide victory of Fidesz. The new government introduced a structured policy focused on engaging Hungarian diaspora, largely due to the nationalist rhetoric of the governing party. The article argues that this change reflects a turn of Hungarian nationalism into what Ragazzi and Balalowska (2011) have called post-territorial nationalism, where national belonging becomes disconnected from territory. It is because of this new conception of Hungarian nationalism that we witness the Hungarian government approach Hungarian communities living in other countries in new ways while using new policy tools: the offer of extraterritorial citizenship; political campaigns to motivate the diaspora to take part in Hungarian domestic politics by voting in legislative elections; or the never-before-seen high state budget allocated to support these communities. Our analysis is based on qualitative data gathered in 2016 from focus group discussions conducted in the Hungarian community of Western Canada to understand the effects of this diaspora politics from a bottom-up perspective. Using the theoretical framework of extraterritorial citizenship, external voting rights and diaspora engagement programmes, the paper gives a brief overview of the development of the Hungarian diaspora policy. We focus on how post-territorial nationalism of the Hungarian government after 2010 effects the ties of Hungarian communities in Canada with Hungary, how the members of these communities conceptualise the meaning of their “new” Hungarian citizenship, voting rights and other diaspora programmes. We argue that external citizenship and voting rights play a crucial role in the Orbán government’s attempt to govern Hungarian diaspora communities through diaspora policy.


1994 ◽  
Vol 30 (1) ◽  
pp. 23-32 ◽  
Author(s):  
John R. Argue

The water resources crisis facing countries of the Mediterranean Basin is reflected, in diminished form, in the semi-arid, “Mediterranean-climate” zone of Australia. Some creative solutions involving the collection, treatment, storage, retrieval and use of storm runoff to replace the component of mainssupplied water presently used for “second quality” purposes, are emerging in Adelaide, capital city of South Australia. The paper describes one initiative being taken to achieve source control of stormwater – quantity and quality – in mixed-density residential streets. The resulting streetscape is suitable for use in both “greenfields” and re-development projects. The paper explores the hydrological/hydraulic performance of the system and shows that it satisfies all theoretical- requirements for safety in the full range of flooding up to and including the “once in 100-years” event. The new streetscape holds the following advantages over conventional streetscapes : reduced peak outflows, greatly improved effluent water quality, aids “greening” of the landscape, potential for aquifer recharge where appropriate, aquiferretrieved groundwater can replace mains water used for irrigation, “nuisance” flows are fully contained (no surface appearance), major flows only occupy the swale, street residences are less flood prone and the streetscape fits more harmoniously into undulating terrain.


1981 ◽  
Vol 59 (12) ◽  
pp. 2595-2602 ◽  
Author(s):  
Anita M. Payne ◽  
M. A. Maun

Cakile edentula (Bigel) Hook var. lacustris occurs abundantly along sandy beaches of Lakes Huron, Erie and Ontario. Until now the species had not been reported to occur along Georgian Bay but we located one population at Deanlea Beach. The deciduous upper fruit segments disperse long distances by water waves and currents and short distances by rolling caused by strong winds. The lower fruit segments usually remain attached to the parents which may be uprooted by high waves and then transported as tumble weeds to new locations. The floatation experiment showed that the agitation of jars containing the fruits improved their floating ability. Agitated upper fruit segments showed a significantly lower sinking index than agitated lower fruit segments and upper and lower fruit segments in the still treatment. The overwintering of fruits improved their floating ability.


2009 ◽  
Vol 9 (1) ◽  
pp. 1521-1560 ◽  
Author(s):  
M. Beekmann ◽  
R. Vautard

Abstract. The variability of the relative sensitivity to volatile organic compounds (VOC) or NOx emissions, the chemical regime, over Europe during summers 2001 to 2003 is simulated with a regional scale transport-chemistry model. The robustness of chemical regimes is shown. A VOC sensitive regime over North-Western Europe and a mainly NOx sensitive regime over the Mediterranean basin and Eastern Europe are found, confirming earlier published results. The chemical regime time variability, its robustness to several environmental factors (seasonality, interannual variability) and to model uncertainty are thoroughly analysed. The chemical regime spatial structure only slightly depends on the ozone target considered (daily ozone maximum or AOT40, SOMO35, ...). Differences between particular years and summer months are weak. Day to day variability is significant but does not change the occurrence of one or another chemical regime over North-Western Europe and the Mediterranean basin. Expected decreases in anthropogenic NOx emissions over Europe since the last and for the next few decades have shifted and will shift chemical regimes to more NOx sensitive. The predictive and explanatory use of chemical regime indicator species is also investigated. For all cases but near ship tracks over the Mediterranean basin, the spatial pattern of chemical regimes appears to be robust with respect to model uncertainty.


2022 ◽  
Vol 78 (02) ◽  
pp. 6619-2022
Author(s):  
WIESŁAW NIEDBALSKI

The article reviews the history of BT occurrence in Europe and its present status. It describes the distribution of BT in Europe before 1998, the emergence of BTV in southern and eastern Europe in 1998-2006 and the epidemiology of BT in north-western Europe after 2006. Up to 1998, sporadic cases of BT were noted in Cyprus, on the Iberian Peninsula and on several Greek islands. However, since 1998, probably due to climatic changes, BTV has spread northwards into the Mediterranean Basin, where five BTV serotypes (1, 2, 4, 9 and 16) have been identified. In August 2006, BTV passed for the first time latitude 50°N, and BT outbreaks caused by BTV serotype 8 occurred in the Netherlands, Belgium, Germany, France and Luxembourg. Mass vaccination campaigns implemented in Europe in the spring of 2008 quickly limited the spread of disease caused by BTV-8, and it was eradicated by 2011. However, after a 3-year break, in September 2015, BTV-8 re-emerged in Europe, in central France, and subsequently spread throughout the entire country. In the following years, BTV-8 outbreaks were found in Switzerland, Germany, Belgium and Spain. In addition to BTV-8 outbreaks, BTV serotypes 1, 2, 4, 9 and 16 have recently circulated in Europe. As revealed by phylogeographic inference, the recent spread of BTV in Europe is a consequence of climatic, landscape and vertebrate host factors


1992 ◽  
Vol 6 ◽  
pp. 69-69
Author(s):  
Simon Conway Morris

Ediacaran taxa are a characteristic element of latest Precambrian biotas, with an effectively global distribution. Their time range is not well understood, but with one possible exception from western Canada Ediacaran faunas appear always to post-date the late Precambrian glaciations. There is also growing evidence that many Ediacaran taxa disappeared before the Precambrian-Cambrian boundary. These disappearances traditionally have been ascribed to changes in taphonomic circumstances, but a series of extinctions is a plausible alternative. Ediacaran fossils pose two major problems: Notwithstanding the reasons for their disappearance shortly before the Precambrian-Cambrian boundary, was their demise total or did some forms persist into the Cambrian? Second, is the traditional view that Ediacaran taxa are metazoans, many of a cnidarian grade, correct? Recently Seilacher, Bergström and others have argued that the Ediacaran organisms have a distinctive bauplan, difficult to reconcile with known phyla and possibly different from any metazoan.In the Cambrian, Burgess Shale-type faunas are the principal source of information on soft-bodied metazoans. The differences between them and Ediacaran assemblages are largely self-evident, but there is now unequivocal evidence for at least one Ediacaran survivor from the Middle Cambrian Burgess Shale of British Columbia. This is a sea-pen-like animal, known from three specimens (one adult about 20 cm in length, and two juveniles). The fossils consist of a broad frond, with branches arising from a central axis on one side, while the opposite side is smooth apart from longitudinal ridges. The frond extends into a blunt holdfast that presumably was embedded in the muddy silt of the sea floor. This fossil is strikingly similar to the Ediacaran taxon Charniodiscus, best known from South Australia. The Burgess Shale example shows two important features. The first are pustule-like structures, possibly zooids, both on the branches and adjacent to the axis. The second feature is evidence for connections between the branches and axis, possibly representing canals. These features both support a comparison with extant pennatulaceans, and suggest that at least some Ediacaran taxa are correctly assigned to the metazoans.Also occurring in the Burgess Shale is an enigmatic bag-like organism Mackenzia costalis. Clear evidence exists for it being benthic, but its mode of feeding is uncertain. The interior appears to have consisted largely of a spacious cavity, probably sub-divided by longitudinal partitions. In addition, an elongate strand may represent a discrete organ, perhaps connected with digestion or reproduction. No exact equivalent to Mackenzia appears to occur in Ediacaran assemblages, but bag-like taxa are a common component. These include erniettids, best known from Namibia, and Platypholina, from the White Sea region of Russia.


2020 ◽  
Vol 11 (5) ◽  
pp. 210-217
Author(s):  
Donato Traversa

In the recent decades, the geographic distribution of vector-borne diseases (VBDs) of dogs and cats has changed for intrinsic and extrinsic reasons. Therefore some infections/infestations, some of zoonotic concern, have been recorded in geographic areas where they were unexpected. In Europe, arthropods (e.g. ticks, fleas, mosquitoes and sand flies) and the pathogens that they transmit are in general considered to be more frequent in the Mediterranean Basin. Nonetheless, a possible occurrence in other regions should not be a priori excluded, given that travels of animals (to or imported from endemic areas), movements of goods and global warming all may foster the introduction of vectors and/or transmitted pathogens in previously free areas. This could also be the case in the UK, which, because of its territorial characteristics as an island area in north-western Europe, is traditionally considered at minor risk of VBDs. Given the growing increase of movements and travels of pets, and changes in the phenology of many arthropod vectors, it is crucial that veterinary practitioners are aware of and prepared to diagnose, treat and control a series of unexpected diseases.


2003 ◽  
Vol 77 (2) ◽  
pp. 267-292 ◽  
Author(s):  
Xueping Ma ◽  
Jed Day

Study of the shell features of Givetian and Frasnian spiriferid brachiopods attributed to the genus Cyrtospirifer shows that the type species C. verneuili has micro-ornament consisting of fine concentric growth lines, radial capillae, with microspines arising from some capillae, spine bases appear to extend into the primary shell layer. Its dorsal interior features a pseudoseptum supporting the cardinalia. Micro-ornament of Cyrtospirifer varies widely and is a useful criterion for characterization of species of the genus. Most Frasnian species retained in the genus have micropustulate shells. Two late Givetian and Frasnian phylogenetic species groups of Cyrtospirifer are recognized based on similarities of shell form and external and internal shell features. Species of the verneuilisyringothyriformis group have transverse alate shells, and are the most abundant and widespread group in Frasnian deposits worldwide. The verneuiliformis group includes the oldest known species of Cyrtospirifer with narrow hinges and more inflated ventral valves where shell width is close to or equal to length. The oldest Cyrtospirifer originated in western Europe during the late Givetian, and subsequently migrated at different times during the Frasnian into other shelf areas of Eurasia, North America and China. The initial migration of Cyrtospirifer into tropical and subtropical shelf settings in North America coincided with the middle Frasnian eustatic sea level rise of Devonian Transgressive-Regressive (T-R) cycle IIc of Johnson and others. A second late Frasnian dispersal from western Canada to subtropical carbonate and clastic shelves in the southwestern and central U.S. coincided with the initial sea level rise of T-R cycle IId of Johnson and others. The Frasnian species Cyrtospirifer glaucus Crickmay, 1952a (middle Frasnian of western Canada) is the type species for Regelia Crickmay, 1952b, and is considered a valid genus, and is not a synonym of C. chemungensis (Conrad, 1842) as previously interpreted by some authors. Regelia differs from Cyrtospirifer in the absence of a delthyrial plate, complete in-filling of the delthyrial cavity by secondary shell material, its simpler rod-like teeth, and its fewer medial sinal shell plications. Species of Regelia are restricted to the middle to late Frasnian of North America.


2021 ◽  
Author(s):  
Lorenzo Pubblici

This book is a synthesis of the great migrations of the 6th-13th centuries, focused on the median space between the two extremes of the Eurasian continent: Western Europe and Eastern Asia. In the light of the sources, it aims to reassess the complexity of the relationships between the nomads of the steppes and the sedentarized societies that came into contact with them. The choice to focus on the Qïpčaq-Cumans is due to their history, unique because they never constituted an organized and centralized center of collective power (stateless nomads); and paradigmatic, because it encompasses all the constitutive elements of steppe nomadism: social heterogeneity, mobility, military preparation, attraction for trade and willingness to negotiate. The migrations of the nomads of the steppes and their arrival close to the great organized communities of the Islamic and Christian world, from Asia to Europe, contributed to triggering a process of integration between Asia and the Mediterranean basin, a process that the Mongol invasion and conquest completed, giving birth to a new shared global space.


Sign in / Sign up

Export Citation Format

Share Document