Identifying pollen grains of Typha latifolia, Typha angustifolia, and Typha ×glauca

2003 ◽  
Vol 81 (9) ◽  
pp. 985-990 ◽  
Author(s):  
Sarah A Finkelstein
Keyword(s):  
Typha Latifolia ◽  
Pollen Grains ◽  
Pollen Record ◽  
Typha Angustifolia ◽  
North American Continent ◽  
Statistical Confidence ◽  
The North ◽  
Pollen Diagrams ◽  
Sparganium Eurycarpum ◽  
Typha Glauca

Typha angustifolia L. and Typha ×glauca Godron have increased their ranges on the North American continent over the past 150 years, and the pollen record has potential to document this spread. In T. angustifolia, pollen disperses as a reticulate, monoporate monad, similar in appearance to the pollen of Sparganium eurycarpum Engelm. Typha angustifolia and Sparganium are generally not distinguished, and T. ×glauca is rarely shown on pollen diagrams. My study of pollen reference material shows that Typha monads and Sparganium can be separated using diameter and roundness at a known level of statistical confidence. Typha monads are on average significantly smaller in diameter (mean and standard deviation = 22.7 ± 2.6 µm) than Sparganium (25.3 ± 2.7 µm). The incidence of angularity is higher in T. angusti folia pollen grains, whereas Sparganium grains are more often rounded. The pollen signature of T. ×glauca consists of mostly monads, but can contain up to 30% dyads, and (or) 14% tetrads, and (or) 10% triads. I suggest that T. angusti folia and T. ×glauca can be identified as one category in the pollen record and, where their dates of arrival are known, this category may be used as a chronostratigraphic indicator.Key words: Typha, Sparganium, pollen, invasive species, wetlands.

Morphological analysis of genetically identified cattails Typha latifolia, Typha angustifolia, and Typha ×glauca

1999 ◽  
Vol 77 (6) ◽  
pp. 906-912 ◽  
Author(s):  
Monica Marcinko Kuehn ◽  
Bradley N White
Keyword(s):  
Discriminant Analysis ◽  
Parental Species ◽  
Typha Latifolia ◽  
Spike Length ◽  
Morphological Data ◽  
Leaf Width ◽  
Morphological Identification ◽  
Typha Angustifolia ◽  
Accurate Identification ◽  
Typha Glauca

Hybridization between the cattail species Typha latifolia L. and Typha angustifolia L. is frequent throughout northeastern and central North America. While studies are required to elucidate the ecological role of interspecific hybrids, morphological intergradation of the hybrids and parental species limits accurate identification. Although species-specific molecular markers have been developed, some researchers do not have the resources necessary for molecular analysis. Consequently, this study used genetically identified specimens of T. latifolia,T. angustifolia, and their hybrid Typha ×glauca Godr. to discriminate sound taxonomic characters for morphological identification. Leaf width, spike gap, spike width, and spike length were measured for 153 specimens of cattails from Massachusetts, Ontario, Quebec, and Manitoba. In addition, stigma width was measured using a compound microscope. Morphological data were used in discriminant analysis; approximately 90% of the classifications derived by discriminant analysis corresponded to the genetic identity. Discriminant analysis using stigma width, spike length, spike interval and leaf width provided accurate identification for 28 of 31 T. angustifolia specimens, 38 of 41 T. ×glauca specimens, and 20 of 25 T. latifolia specimens. Thus, discriminant analysis of morphological characters can be used to distinguish the hybrid cattail from the parental species with reasonable confidence when molecular resources are not available.Key words: Typha, cattails, discriminant analysis, DNA markers.

scholarly journals Striking forest revival at the end of the Roman Period in north-western Europe

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
C. Lambert ◽  
A. Penaud ◽  
M. Vidal ◽  
C. Gandini ◽  
L. Labeyrie ◽  
...  
Keyword(s):  
North Atlantic ◽  
Western Europe ◽  
Anthropogenic Activities ◽  
Sedimentary Environment ◽  
Pollen Grains ◽  
Roman Period ◽  
Freshwater Microalgae ◽  
Environmental Signals ◽  
The North ◽  
North Western

AbstractThe Holocene period (last 11,700 years BP) has been marked by significant climate variability over decadal to millennial timescales. The underlying mechanisms are still being debated, despite ocean–atmosphere–land connections put forward in many paleo-studies. Among the main drivers, involving a cluster of spectral signatures and shaping the climate of north-western Europe, are solar activity, the North Atlantic Oscillation (NAO) varying atmospheric regimes and North Atlantic oceanic gyre dynamics. Over the last 2500 years BP, paleo-environmental signals have been strongly affected by anthropogenic activities through deforestation and land use for crops, grazing, habitations, or access to resources. Palynological proxies (especially pollen grains and marine or freshwater microalgae) help to highlight such anthropogenic imprints over natural variability. Palynological analyses conducted in a macro-estuarine sedimentary environment of north-western France over the last 2500 years BP reveal a huge and atypical 300 year-long arboreal increase between 1700 and 1400 years BP (around 250 and 550 years AD) that we refer to as the ‘1.7–1.4 ka Arboreal Pollen rise event’ or ‘1.7–1.4 ka AP event’. Interestingly, the climatic 1700–1200 years BP interval coincides with evidence for the withdrawal of coastal societies in Brittany (NW France), in an unfavourable socio-economic context. We suggest that subpolar North Atlantic gyre strengthening and related increasing recurrence of storminess extremes may have affected long-term coastal anthropogenic trajectories resulting in a local collapse of coastal agrarian societies, partly forced by climatic degradation at the end of the Roman Period.

Some Experiments and Observations on the Longevity of Diphyllobothrium Infections

1936 ◽  
Vol 14 (3) ◽  
pp. 127-130 ◽  
Author(s):  
R. T. Leiper
Keyword(s):  
Adult Life ◽  
Infected Fish ◽  
Human Infection ◽  
Natural Occurrence ◽  
Natural Area ◽  
North American Continent ◽  
The North ◽  
History Of ◽  
Typical Instance ◽  
Diphyllobothrium Latum

In an article on “The Longevity of Diphyllobothrium latum” published in 1935 in the “Recueil des Travaux dédié au 25-me Anniversaire Scientifique du Professeur Eugène Paviosky 1909−1934”, it is suggested that present day conceptions regarding the longevity of this parasite are erroneous and that multiple successive infections are frequently attributed to a single long-lived specimen. Ward gives a detailed review and analysis of the evidence hitherto published both in general works and special monographs and cites as specially important the history of the occurrence of this species on the North American continent. He points out that the age of the parasite is regularly based on the statement that the host had not been in an infected region for the period indicated. To this statement, Ward puts forward the objections that the distribution of the parasite and the natural occurrence of plerocercoid carrying fish are far more extensive than was formerly suspected and, further, that infected fish are distributed commercially as food to regions far outside their natural area of distribution. He also refers to certain records which seem to indicate that there is a “period of inactivity” during the adult life of the parasite and suggests that its alleged occurrence throws doubt upon the supposed longevity of the parasite. In support of this contention, he cites, as a typical instance, a case of human infection with Diphyllobothrium latum reported by me (Leiper, 1928) as a “cryptic infection”; regarding which he erroneously states that I believed was “latent” for 5 years.

scholarly journals Late Glacial and Holocene plant cover in Węgliny, Lubsza Plain, south-west Poland, based on pollen analysis

2013 ◽  
Vol 53 (2) ◽  
pp. 191-233 ◽  
Author(s):  
Aleksandra Jurochnik ◽  
Dorota Nalepka
Keyword(s):  
Pollen Analysis ◽  
Plant Cover ◽  
Late Glacial ◽  
Anaerobic Sediments ◽  
The North ◽  
South West ◽  
Pollen Diagrams ◽  
Laacher See Tephra ◽  
Late Glacial And Holocene

ABSTRACT Late Glacial (since Oldest Dryas) and Holocene (to Subatlantic) changes of vegetation at the Węgliny site (south-west Poland) are reconstructed based mainly on pollen analysis of five cores from the palaeobasin (anaerobic sediments). The chronology of the described events is based on palynological comparison with the Lubsza Plain environs, based on LPAZs from several published pollen diagrams on 14C data, and multiple cryptotephra levels determined in the Węgliny profiles. The Węgliny record integrates well into the north European Holocene and Late Glacial biostratigraphic framework. The Węgliny site is the next (fourth) locality in Poland where the Laacher See Tephra (LST) horizon within the Allerød chronozone was identified.

scholarly journals Q fever in South Australia: an outbreak in a meat-works

1962 ◽  
Vol 60 (1) ◽  
pp. 1-20 ◽  
Author(s):  
Margaret D. Beech ◽  
A. E. Duxbury ◽  
Peter Warner
Keyword(s):  
Q Fever ◽  
South Australia ◽  
Meteorological Conditions ◽  
American Continent ◽  
North American Continent ◽  
The Past ◽  
The North ◽  
Epidemiological Features ◽  
Very High ◽  
Abattoir Workers

This paper consists of an epidemiological study of 52 cases of Q fever occurring in metropolitan Adelaide in 1957 and also a description of the results of a survey of 516 sera obtained from abattoir workers.The only case occurring outside the abattoirs was a dairy farmer who probably became infected while visiting the abattoirs. If this were so the incubation period (35 days) of his disease would have been exceptionally long.The general features of the outbreak, which lasted several months, differed from those on the North American continent in that the latter occurred explosively within a few days with very high attack rates. The situation in the Adelaide abattoirs is similar to that in Brisbane, where the disease appears to be endemic. However, unlike in Adelaide, cases are commonly recognized outside the abattoirs in Brisbane.In the abattoirs the disease affected mainly inspectors, those working on killing beef, and those working on offal. Mutton workers were not so severely affected. However, all these groups had similar incidences of low titre antibodies suggesting that in the past Q fever spread equally in all killing departments. In departments not directly associated with slaughtering the incidence both of cases in 1957 and low titre antibodies was relatively small.It was suggested that the epidemiological features of Q fever in Adelaide could be explained by the irregular appearance of animals from infected herds situated perhaps in Queensland—a known endemic area. Perhaps the appearance of such animals in the Adelaide abattoirs might be governed by meteorological conditions such that they were prevented from going to the ordinarily most convenient slaughterhouse.

An inverse relationship between moisture and grazing intensity in an arid mountain-basin system

2021 ◽  
pp. 030913332110600
Author(s):  
Jun Zhang ◽  
Xiao-zhong Huang ◽  
Jia-le Wang ◽  
Richard HW Bradshaw ◽  
Tao Wang ◽  
...  
Keyword(s):  
Arid Region ◽  
Influencing Factor ◽  
Regional Climate ◽  
Fungal Spores ◽  
Grazing Intensity ◽  
Pollen Grains ◽  
High Mountains ◽  
Spores And Pollen ◽  
The North ◽  
Basin System

Precipitation has been suggested as a crucial influencing factor in the primary productivity in arid and semi-arid regions, yet how moisture fluctuation in an arid mountain-basin system of the north Qinghai–Tibetan Plateau has affected human activities is poorly understood. Here, we reconstruct the variations of grazing intensity in high elevations and regional humidity based on independent and high-resolution records of Sporormiella-type coprophilous fungal spores and pollen grains in the same well-dated sediment core from Lake Tian’E in the western Qilian Mountains over the past 3500 years. We find that stronger grazing activity was associated with low regional effective moisture, and propose that the drier regional climate pushed people and their livestock into the mountainous areas. A notable exception was a reduction of human and grazing activities in arid region with high mountains during 380–580 CE caused by centennial-length dry and cold conditions. In addition, it is also noteworthy that intensified grazing activity occurred during 580–720 CE and after ∼1920 CE, corresponding to a warmer and wetter climate and diverse subsistence strategies with social developments in the lowlands of the Hexi Corridor. Our findings potentially provide a historical reference for understanding how ancient people adapted to the climate change in arid region with high mountains.

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