scholarly journals Spatiotemporal patterns of phenology of the alien Phaeophyceae Sargassum muticum on the Atlantic coast of Morocco

2021 ◽  
Vol 85 (2) ◽  
pp. 103-111
Author(s):  
Samir El Atouani ◽  
Zahira Belattmania ◽  
Soukaina Kaidi ◽  
Aschwin H. Engelen ◽  
Ester A. Serrão ◽  
...  
Keyword(s):  
Life Cycle ◽  
Atlantic Coast ◽  
Early Summer ◽  
Spatiotemporal Patterns ◽  
Sargassum Muticum ◽  
Growth Phases ◽  
Sandy Bottom ◽  
Body Depth ◽  
Rocky Substratum ◽  
High Elongation

The present study focused on the dynamics of the phenology and life cycle of the Phaeophyceae invader Sargassum muticum at three sites on the Atlantic coast of Morocco over a period of two years (2013 and 2014). The results showed that S. muticum has two distinct growth phases; one with slower growth in winter followed by one with faster growth in spring-early summer, when the species exhibited high elongation and branching activities with thalli length ranging from 1 to more than 5 m depending on the study site. The site S1, with a rocky substratum covered by submerged sands, promotes thalli elongation, with maximum lengths of 643.33 11.10 cm recorded in July. At the rocky sites (S2 and S3), the maximum length of the seaweed depends on the pools’ depth. Although the elongation of thalli is enhanced by the water body depth, the settlements’ density (5-48 ind. m–2) seems to be mainly related to the nature of the substrate. The maturity index progressively increases from spring to early summer, when it reaches the highest values. S. muticum seems to be more abundant and more easily acclimated in shallow rockpools (sufficiently lighted and semi-exposed to wave action at the mid and lower tidal levels) than in protected sandy bottom sites with low hydrodynamic forces.

Seasonal patterns of growth, alginate content and block structure of the alien invader Sargassum muticum (Fucales, Ochrophyta) from the Atlantic coast of Morocco

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Zahira Belattmania ◽  
Samir El Atouani ◽  
Fouad Bentiss ◽  
Charafeddine Jama ◽  
Annalisa Falace ◽  
...  
Keyword(s):  
Vegetative Growth ◽  
Block Structure ◽  
Atlantic Coast ◽  
Late Summer ◽  
Early Summer ◽  
Sargassum Muticum ◽  
Early Autumn ◽  
Commercial Applications ◽  
Alien Invader ◽  
G Ratio

Abstract In the present study, alginate yield and composition were investigated during the seasonal life cycle of the alien brown alga Sargassum muticum harvested from the Atlantic coast of Morocco. Alginate yield ranged from 11.14% in winter to 25.62% in spring/early summer, coinciding with maximum vegetative growth. Monthly monitoring of the alginate block structure showed that the highest mannuronate (M)/guluronate (G) ratio was recorded during the maximum development of S. muticum, before sexual maturity and during resumption of vegetative growth, giving maximum flexibility to the alga. The unusually high molar monad fractions (FG) and dyad fractions (FGG) of guluronic acid in late summer/early autumn appeared to be related to stiffness of senescent thalli. Rheological characterisation showed that the alginate of S. muticum exhibited pseudoplastic behaviour, with the highest apparent viscosities measured in late summer/early autumn when the G blocks dominated the alginate structure. This study suggests that S. muticum could be exploited as an alginophyte for commercial applications. The best harvest time is May-June, which corresponds to the highest alginate yield, maximum thallus growth, and largely completed sexual reproduction, ensuring sustainable exploitation of the species.

The life-cycle of Bucephalus haimeanus Lacaze-Duthiers, 1854 from Cardium edule L.

Parasitology ◽  
1973 ◽  
Vol 67 (3) ◽  
pp. 341-350 ◽  
Author(s):  
R. A. Matthews
Keyword(s):  
Life Cycle ◽  
Cyst Wall ◽  
Adult Stage ◽  
Comparative Morphology ◽  
Early Summer ◽  
Host Tissue ◽  
Remaining Life ◽  
Estuarine Habitat ◽  
Main Site ◽  
First Time

Bucephalus haimeanus is shown to be an estuarine species. The cercaria from Cardium edule is briefly redescribed to include details of the nephridial system. The metacercaria is described for the first time, having been obtained experimentally in Pomatoschistus microps and Pleuronectes platessa. In Pomatoschistus microps it survives at least 10 months, development within this host being completed within 2 months. The main site of infection is the liver. Migration is completed within 1 h and in some instances within 10 min. During this period the metacercaria actively feeds on host tissue, the gut being greatly distended with food on encystment. A hyaline cyst wall is maintained throughout the remaining life of the metacercaria. ‘O’ group plaice are highly susceptible to invasion by B. haimeanus during early summer and 100% infections were recorded in catches from Ynys-las, Dovey Estuary, in June. Experiments showed that only 2% of the metacercariae survived more than two weeks and that ‘l’ group plaice were non-susceptible to infection. Plaice are therefore considered accidental hosts. The metacercaria was linked with the adult stage from Morone labrax on the basis of comparative morphology and the ecology of the hosts, the bass entering the estuarine habitat during the summer months. The adult is considered synonymous with Bucephalus minimus Stossich, 1887.

scholarly journals Some New Observations on the Developmental Cycle of the Organism of Bovine Pleuropneumonia and Related Microbes

1942 ◽  
Vol 42 (2) ◽  
pp. 110-123 ◽  
Author(s):  
Emmy Klieneberger ◽  
J. Smiles
Keyword(s):  
Life Cycle ◽  
Staining Technique ◽  
Developmental Cycle ◽  
Growth Phases ◽  
New Methods ◽  
Ground Method ◽  
Dark Ground ◽  
Good Agreement

A study of the growth phases of pleuropneumoma has been carried out by two new methods: (1) a new fixing and staining technique, (2) a new dark-ground method. The results obtained by the two methods are in good agreement, and the life cycle of the organism of bovine pleuropneumoma and related microbes as revealed by means of both methods has been described.

Life cycles of four species of Pseudocalanus in Nova Scotia

1989 ◽  
Vol 67 (3) ◽  
pp. 552-558 ◽  
Author(s):  
I. A. McLaren ◽  
Estelle Laberge ◽  
C. J. Corkett ◽  
J.-M. Sévigny
Keyword(s):  
Life Cycle ◽  
Nova Scotia ◽  
First Generation ◽  
Early Summer ◽  
Life Cycles ◽  
The Arctic ◽  
Late Winter ◽  
Early Winter ◽  
Temperature Dependent ◽  
Scotian Shelf

The primarily arctic Pseudocalanus acuspes, relict in Bedford Basin, Nova Scotia, produces a first generation (G1) in late winter; most G1 individuals mature in late spring. The G1 then produces a G2, most of which "rest" in copepodite stages III and IV until early winter. These stages store large amounts of lipid in early summer, which slowly diminish subsequently. A small number of G2 individuals continue to develop at temperature-dependent rates, maturing in early autumn and producing G3 adults in November. Copepodites developing in winter and spring store less lipid. The primarily arctic Pseudocalanus minutus, rare in Bedford Basin and on the Scotia Shelf, is strictly annual, developing to a lipid-filled copepodite stage V after spawning in late winter. The arctic–temperate Pseudocalanus newmani is abundant on the Scotian Shelf, but may not be self-sustaining when advected into Bedford Basin. It stores little lipid and appears to have at least three mature generations at temperature-dependent intervals over Browns Bank between May and November. It may rest in winter, or its life-cycle synchrony by spring could result from food-limited development during winter. The temperate Pseudocalanus moultoni appears to have a life cycle similar to that of P. newmani, but was less common during summer on Browns Bank. These life cycles are appropriately adapted to the geographical ranges of the species, and show some parallels with species of Calanus.

Nematodes associated with damage in oilseed rape: new data on the biology and geographical distribution of Meloidogyne artiellia

Nematology ◽  
2014 ◽  
Vol 16 (2) ◽  
pp. 201-206
Author(s):  
Alain Buisson ◽  
Andre Chabert ◽  
Laurent Ruck ◽  
Sylvain Fournet
Keyword(s):  
Life Cycle ◽  
Oilseed Rape ◽  
Atlantic Coast ◽  
Parasitic Nematodes ◽  
Paris Basin ◽  
Plant Parasitic Nematodes ◽  
Mediterranean Species ◽  
Climate Conditions ◽  
Development Stages ◽  
Plant Parasitic

For several years, patches of plants presenting deficiencies in growth have been observed in fields cultivated with oilseed rape. Over 3 years, 57 pairs of damaged and undamaged plants were sampled from cultivated fields on the Atlantic coast of France and around the Paris basin. Results show that two main species of plant-parasitic nematodes can be associated with the patches, Heterodera cruciferae and Meloidogyne artiellia, and that both species probably do not occur in the same fields and regions. This means that M. artiellia, which is considered as a Mediterranean species causing damage essentially on wheat, is also well adapted to colder climate conditions and can extensively damage oilseed rape. Monitoring the different development stages of M. artiellia in a field cultivated with oilseed rape provided more information about the life cycle and showed that only one generation can develop between the sowing in autumn and April.

Life cycle, population dynamics and productivity of Ventrosia maritima in the Evros Delta (northern Aegean Sea)

2005 ◽  
Vol 85 (2) ◽  
pp. 375-382 ◽  
Author(s):  
Theodoros Kevrekidis ◽  
Thomas Wilke
Keyword(s):  
Population Dynamics ◽  
Life Cycle ◽  
Outer Part ◽  
Dry Weight ◽  
Early Summer ◽  
Late Winter ◽  
Published Data ◽  
Annual Life Cycle ◽  
Frequency Method ◽  
Innermost Part

Life cycle, population dynamics and productivity of the larviparous mudsnail species Ventrosia maritima were investigated at low salinities (0·3–6 psu) in differentiated parts of a Mediterranean lagoon (Monolimni Lagoon). Monthly samples were collected during the period from February 1998 to February 1999 in both parts of the lagoon. Ventrosia maritima displayed an annual life cycle. Recruitment occurred in summer and autumn at the outer part of the lagoon and additionally in late winter at the innermost part. A positive correlation was found between the percentages of small individuals and salinity or sediment organic matter at the outer part. Growth practically ceased in winter. The mudsnail displayed remarkable densities and an increase in growth in spring at <1 psu indicating that it is highly tolerant to extremely low salinities. Population density showed a significant seasonal variation; it increased from early summer to autumn (30,000–40,000 individuals m−2) following the summer and autumn recruitment. No significant correlation between the density of V. maritima and several examined physicochemical variables was found; a negative correlation was observed between the density of the mudsnail and that of the co-occurring polychaete Streblospio shrubsolii. Secondary production calculated by the size–frequency method gave a mean annual density (N) of 9740 ind m−2, a mean biomass (B) of 1·66 g ash-free dry weight (AFDW) m−2 y−1, a production (P) of 4·51 g m−2 y−1 and a P:B ratio of 2·72 at the outer part of the lagoon and a N of 14,570 ind m−2, a B of 3·2 g AFDW m−2 y−1, a P of 9·9 g m−2 y−1 and a P:B ratio of 3·09 at the innermost part. At the innermost part of the lagoon, where the seawater renewal rate and hydro-dynamism were lower and the sediment finer and organically richer, V. maritima displayed more recruitment pulses, a larger body size and a denser and more productive population than the one at the outer part. Our findings are compared to published data for the direct-developing congeners V. ventrosa and V. truncata.

Seasonal dynamics and life cycle of Heterotrissocladius marcidus (Diptera: Chironomidae) in high altitude lakes (High Tatra Mts, Slovakia)

Biologia ◽  
2015 ◽  
Vol 70 (7) ◽  
Author(s):  
Katarína Goffová ◽  
Peter Bitušík ◽  
Zuzana Čiamporová-Zatóvičová ◽  
Dana Bukvová ◽  
Ladislav Hamerlík
Keyword(s):  
Life Cycle ◽  
Seasonal Dynamics ◽  
Seasonal Changes ◽  
Alpine Lakes ◽  
Early Summer ◽  
Larval Abundance ◽  
Tatra Mountains ◽  
Tatra Mts ◽  
Summer Decline ◽  
High Tatra Mountains

AbstractWe estimated the seasonal dynamics and life cycle of the chironomid Heterotrissocladius marcidus (Walker, 1856) in three alpine lakes in the High Tatra Mountains (Central Europe). H. marcidus had univoltine cycle in all lakes surveyed and seasonal changes of density showed an early summer and an autumn peak interrupted by a mid-summer decline of larval abundance. Our results indicate that phenology of H. marcidus is sensitive to thermal regime and local differences in lake water temperature can lead to differences of the life history within the same population

scholarly journals Life cycle of ground beetle Chlaenius tristis reticulatus Motschulsky, 1844 (Coleoptera: Carabidae) in the condition of Western Transbaikalia

2020 ◽  
Vol 418 ◽  
pp. 19-24
Author(s):  
L.Ts. Khobrakova ◽  
◽  
S.G. Rudykh ◽  
Ts. Ulzii ◽  
Ch. Gantigmaa ◽  
...  
Keyword(s):  
Soil Moisture ◽  
Life Cycle ◽  
Ground Beetle ◽  
Early Summer ◽  
Related Structure ◽  
Young Generation ◽  
Seasonal Activity ◽  
Western Transbaikalia ◽  
Age Related ◽  
One Year

In the conditions of Western Transbaikalia, Chlaenius tristis reticulatus Motschulsky, 1844 has a one-year late spring – early summer life cycle with the hibernation of a young generation of beetles. The interpretation of their life cycle is based on the study of sex and age-related structure of imago, the seasonal activity of generative females, the above-ground activity of larvae, and stages of the development of beetles in the laboratory conditions. The changes in the seasonal activity of beetles on meadows with different soil moisture (steppificated, moistened, and marshy meadows) were identified.

Seasonal occurrence of waterbirds in Minas Passage, Bay of Fundy, Nova Scotia, Canada, 2010 to 2012

2021 ◽  
Vol 135 (2) ◽  
pp. 124-141
Author(s):  
Patrick L. Stewart ◽  
Fulton L. Lavender ◽  
Heather A. Levy
Keyword(s):  
Nova Scotia ◽  
Atlantic Coast ◽  
Early Summer ◽  
Seasonal Abundance ◽  
Bay Of Fundy ◽  
Somateria Mollissima ◽  
Migration Pathway ◽  
Cepphus Grylle ◽  
Surf Scoter ◽  
Abundance And Diversity

We determined patterns of seasonal abundance and diversity of seabirds and coastal waterfowl in Minas Passage, Bay of Fundy, Nova Scotia, Canada using quantitative, shore-based point surveys from mid-March to late August and mid-October to December 2010 to 2012. This area experiences the world’s highest tides and greatest tidal currents. We showed that species and seasonal cycles of waterbirds in Minas Passage reflect patterns typical of the inner Bay of Fundy and the northeast Atlantic coast of North America. The study highlights the importance of Minas Passage as an important local migration pathway for waterbirds including Black Scoter (Melanitta americana) and Red-throated Loon (Gavia stellata) passing through the Bay of Fundy. Large numbers of sea ducks (Black Scoter, Surf Scoter [Melanitta perspicillata], White-winged Scoter (Melanitta fusca), and Long-tailed Duck [Clangula hyemalis]), and Red-throated Loon were observed at the site in spring and fall, corresponding to known peak movements elsewhere in the Bay of Fundy. Fewest species and smallest abundances of waterbirds overall occurred in summer and early winter, while most species and largest abundances occurred in April-May and early November. Of the 46 species observed, resident breeders such as Herring Gull (Larus argentatus), Great Black-backed Gull (Larus marinus), Common Eider (Somateria mollissima), Black Guillemot (Cepphus grylle), and Double-crested Cormorant (Phalacrocorax auritus), were most abundant in spring to early summer during breeding and migrants including Red-throated Loon, Black Scoter, Ring-billed Gull (Larus delawarensis), Surf Scoter, and Northern Gannet (Morus bassanus) occurred in moderate numbers during migration periods.

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