scholarly journals Design and optimization of an experimental maintenance system for yellow clam broodstock Amarilladesma mactroides (Reeve, 1854)

2022 ◽  
Vol 82 ◽  
Author(s):  
N. B. Gauthier ◽  
F. S. Goes ◽  
L. Quaresma ◽  
V. F. Pedrosa ◽  
F. Roselet ◽  
...  
Keyword(s):  
Anthropogenic Activities ◽  
Feasibility Studies ◽  
Gonadal Development ◽  
North Coast ◽  
Oocyte Diameter ◽  
High Survival ◽  
Design And Optimization ◽  
The North ◽  
Management Protocol ◽  
In Captivity

Abstract The yellow clam is a sand-burrowing bivalve that inhabits the dissipative beaches from southern Brazil to the north coast of Argentina. In the last decades, populations of this species have been impacted by mass mortality events, overfishing and other anthropogenic activities. The production of juveniles in captivity would allow feasibility studies to be carried out to restore the natural stock as well as the production in aquaculture systems. Given the scarcity of studies on the maintenance of this species in captivity, a culture system and a management protocol were developed and tested. Wild-caught clams (total length ≥50 mm) were used in a series of 14 day-long trials. Survival was higher in clams that were allowed to bury into the sand. A permanent ink marker covered with a thin layer of a quick-hardening adhesive proved to be a reliable method to tag clams. The maintenance of yellow clams in this system resulted in high survival and growth, increases in the condition factor and oocyte diameter, and a relative advancement of gonadal development.

scholarly journals The Pattern of Change in the Abundances of Specific Bacterioplankton Groups Is Consistent across Different Nutrient-Enriched Habitats in Crete

2014 ◽  
Vol 80 (13) ◽  
pp. 3784-3792 ◽  
Author(s):  
Stilianos Fodelianakis ◽  
Nafsika Papageorgiou ◽  
Paraskevi Pitta ◽  
Panagiotis Kasapidis ◽  
Ioannis Karakassis ◽  
...  
Keyword(s):  
Nutrient Enrichment ◽  
Anthropogenic Activities ◽  
North Coast ◽  
Common Source ◽  
Content Type ◽  
Dissolved Nitrogen ◽  
The North ◽  
Change Pattern ◽  
Α Diversity ◽  
Taxonomic Groups

ABSTRACTA common source of disturbance for coastal aquatic habitats is nutrient enrichment through anthropogenic activities. Although the water column bacterioplankton communities in these environments have been characterized in some cases, changes in α-diversity and/or the abundances of specific taxonomic groups across enriched habitats remain unclear. Here, we investigated the bacterial community changes at three different nutrient-enriched and adjacent undisturbed habitats along the north coast of Crete, Greece: a fish farm, a closed bay within a town with low water renewal rates, and a city port where the level of nutrient enrichment and the trophic status of the habitat were different. Even though changes in α-diversity were different at each site, we observed across the sites a common change pattern accounting for most of the community variation for five of the most abundant bacterial groups: a decrease in the abundance of thePelagibacteraceaeand SAR86 and an increase in the abundance of theAlteromonadaceae,Rhodobacteraceae, andCryomorphaceaein the impacted sites. The abundances of the groups that increased and decreased in the impacted sites were significantly correlated (positively and negatively, respectively) with the total heterotrophic bacterial counts and the concentrations of dissolved organic carbon and/or dissolved nitrogen and chlorophyll α, indicating that the common change pattern was associated with nutrient enrichment. Our results provide anin situindication concerning the association of specific bacterioplankton groups with nutrient enrichment. These groups could potentially be used as indicators for nutrient enrichment if the pattern is confirmed over a broader spatial and temporal scale by future studies.

IMPLANTATION OF LHRH-a HORMONE TO STIMULATION OF GONAD DEVELOPMENT OF HUMPBACK GROUPER SECOND GENERATION ( F-2 )

2013 ◽  
Vol 5 (2) ◽  
Author(s):  
Tridjoko Tridjoko
Keyword(s):  
Body Weight ◽  
Second Generation ◽  
Gonad Development ◽  
Gonadal Development ◽  
Oocyte Diameter ◽  
2Nd Generation ◽  
Length Range ◽  
Concrete Tank ◽  
Implant Treatment ◽  
Stimulation Of

This study aimed to determine the effect of LHRH-a hormone implantation on gonadal development of humpback grouper, Cromileptes altivelis 2nd generation (F-2). Individuals used were 20 female grouper fish with weight range of 600-800 gram/fish and total length range of 28.0-30.0 cm. The treatment used 5 fish each with tagging. Grouper fishes were stocked into the 75 m3 circular concrete tank. Hormone of LHRH-a with dosage of 50 μg/kg body weight was used as implant treatment of (A) 1 time,, (B) 2 times, (C) 3 times, and (D) without implant. The results showed that implantation of LHRH-a hormone were significantly stimulate gonad development of humpback grouper second generation (F-2). Treatment of 3 times implant every month showed the best results produced  oocyte diameter up to 480 μm, while the control of oocyte diameter only reached <400 μm. Keywords: LHRH-a hormone, implantation, Humpback grouper, gonad development

MBAH HENDRO KUSUMO BIN SYECH AHMAD MUTAMAKKIN: JEJAK SYIAR ISLAM DI WILAYAH PATI

EMPIRISMA ◽  
2008 ◽  
Vol 27 (2) ◽  
Author(s):  
Fathimatuz Zahra Dan Abdul Azis
Keyword(s):  
Central Region ◽  
Marital Relationship ◽  
Southern Region ◽  
North Coast ◽  
The North ◽  
Trace Back ◽  
Northern Regions ◽  
The One

Pati is a region on the north coast, according to the hypothesis of the researcher, the region is divided into three categories. The northern regions are more religious, the central is more plural, while the southern region is in the middle. In the central region there are many relics of tombs believed to be the those of the Muslim proselytizers in the area of Pati. The one that attracts the researcher is a tomb in the Gambiran area, where there are five local Muslim saints buried, one of them belons to mbah Hendro Kusumo, the son of Syech Ahmad Mutamakkin. This article attempts to trace back the spreading of Islam in Pati based on the existence of thetomb of Mbah Hendro Kusumo. It wants to answer question of whethere the existence of his tomb is due to his studying there or marital relationship, and how it relates to the spreading of Islam.Keywords: Mbah Hendro Kusumo, Traces of Islamic Dakwah, Islam

4 The Tyara Site

1968 ◽  
Vol 22 ◽  
pp. 44-79 ◽  
Author(s):  
William E. Taylor
Keyword(s):  
Sandy Beach ◽  
North Coast ◽  
National Museum ◽  
The West ◽  
Rock Outcrops ◽  
Small Boat ◽  
The North

The Tyara site, KkFb-7 in the National Museum catalogue and site file, faces the north coast of the Ungava mainland and rests on the west shore of Sugluk Island (Fig. 1). That island stands about five hundred yards from the mainland and from Sugluk Inlet, one of the few good harbors on that coast. This handsome little island, about one and one-half miles long and as wide, consists of rounded, rugged, hardrock hills that shelter well-vegetated, generally flat-floored valleys. The valleys often contain marshy patches. The shore, of variable incline, is quite jagged, a result of abrupt rock outcrops projecting seaward from brief stretches of sandy beach. The shore facing the mainland is, therefore, quite convenient for small boat use. Dark grey gneisses seem to predominate, although they are often cut by dykes and veins of lighter material, notably quartz. The dense, green valley and hillside vegetation includes willows, mosses, grasses, lichens, and a pleasant profusion of arctic wild flowers (Polunin 1948, Pt. III). I was told at Sugluk that at the head of the inlet, willows, growing in protected situations, reach the thickness of a man's wrist.

Seed production and seedling emergence of Giant Parramatta grass on the north coast of New South Wales

1996 ◽  
Vol 36 (3) ◽  
pp. 299 ◽  
Author(s):  
TS Andrews ◽  
RDB Whalley ◽  
CE Jones
Keyword(s):  
Seed Production ◽  
Seed Bank ◽  
New South ◽  
New South Wales ◽  
Seed Banks ◽  
North Coast ◽  
The North ◽  
South Wales ◽  
Seed Fall ◽  
The Impact

Inputs and losses from Giant Parramatta grass [GPG, Sporobolus indicus (L.) R. Br. var. major (Buse) Baaijens] soil seed banks were quantified on the North Coast of New South Wales. Monthly potential seed production and actual seed fall was estimated at Valla during 1991-92. Total potential production was >668 000 seeds/m2 for the season, while seed fall was >146000 seeds/m2. Seed fall >10000 seeds/m2.month was recorded from January until May, with further seed falls recorded in June and July. The impact of seed production on seed banks was assessed by estimating seed banks in the seed production quadrats before and after seed fall. Seed banks in 4 of the 6 sites decreased in year 2, although seed numbers at 1 damp site increased markedly. Defoliation from mid-December until February, April or June prevented seed production, reducing seed banks by 34% over 7 months. Seed banks in undefoliated plots increased by 3300 seeds/m2, although seed fall was estimated at >114 000 seeds/m2. Emergence of GPG seedlings from artificially established and naturally occurring, persistent seed banks was recorded for 3 years from bare and vegetated treatment plots. Sown seeds showed high levels of innate dormancy and only 4% of seeds emerged when sown immediately after collection. Longer storage of seeds after collection resulted in more seedlings emerging. Estimates of persistent seed banks ranged from 1650 to about 21260 seeds/m2. Most seedlings emerged in spring or autumn and this was correlated with rainfall but not with ambient temperatures. Rates of seed bank decline in both bare and vegetated treatment plots was estimated by fitting exponential decay curves to seed bank estimates. Assuming no further seed inputs, it was estimated that it would take about 3 and 5 years, respectively, for seed banks to decline to 150 seeds/m2 in bare and vegetated treatments.

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.

scholarly journals The Potential of GRASP/GARRLiC Retrievals for Dust Aerosol Model Evaluation: Case Study during the PreTECT Campaign

2021 ◽  
Vol 13 (5) ◽  
pp. 873
Author(s):  
Dimitra Konsta ◽  
Alexandra Tsekeri ◽  
Stavros Solomos ◽  
Nikolaos Siomos ◽  
Anna Gialitaki ◽  
...  
Keyword(s):  
Model Evaluation ◽  
Dust Concentration ◽  
Saharan Dust ◽  
North Coast ◽  
Concentration Profiles ◽  
Future Studies ◽  
Aerosol Model ◽  
The North ◽  
Sun Photometer

We use the Generalized Retrieval of Aerosol Surface Properties algorithm (GRASP) to compare with dust concentration profiles derived from the NMME-DREAM model for a specific dust episode. The GRASP algorithm provides the possibility of deriving columnar and vertically-resolved aerosol properties from a combination of lidar and sun-photometer observations. Herein, we apply GRASP for analysis of a Saharan dust outburst observed during the “PREparatory: does dust TriboElectrification affect our ClimaTe” campaign (PreTECT) that took place at the North coast of Crete, at the Finokalia ACTRIS station. GRASP provides column-averaged and vertically resolved microphysical and optical properties of the particles. The retrieved dust concentration profiles are compared with modeled concentration profiles derived from the NMME-DREAM dust model. To strengthen the results, we use dust concentration profiles from the POlarization-LIdar PHOtometer Networking method (POLIPHON). A strong underestimation of the maximum dust concentration is observed from the NMME-DREAM model. The reported differences between the retrievals and the model indicate a high potential of the GRASP algorithm for future studies of dust model evaluation.

scholarly journals Thinner Sea Ice Contribution to the Remarkable Polynya Formation North of Greenland in August 2018

2021 ◽  
Author(s):  
Xiaoyi Shen ◽  
Chang-Qing Ke ◽  
Bin Cheng ◽  
Wentao Xia ◽  
Mengmeng Li ◽  
...  
Keyword(s):  
Sea Ice ◽  
Ice Cover ◽  
Reanalysis Data ◽  
Mean Value ◽  
Ocean Model ◽  
North Coast ◽  
Average Value ◽  
The North ◽  
Wind Sea ◽  
The One

AbstractIn August 2018, a remarkable polynya was observed off the north coast of Greenland, a perennial ice zone where thick sea ice cover persists. In order to investigate the formation process of this polynya, satellite observations, a coupled ice-ocean model, ocean profiling data, and atmosphere reanalysis data were applied. We found that the thinnest sea ice cover in August since 1978 (mean value of 1.1 m, compared to the average value of 2.8 m during 1978–2017) and the modest southerly wind caused by a positive North Atlantic Oscillation (mean value of 0.82, compared to the climatological value of −0.02) were responsible for the formation and maintenance of this polynya. The opening mechanism of this polynya differs from the one formed in February 2018 in the same area caused by persistent anomalously high wind. Sea ice drift patterns have become more responsive to the atmospheric forcing due to thinning of sea ice cover in this region.

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