Reproduction and survival of Phyllorhiza punctata (Cnidaria: Rhizostomeae) in a seasonally fluctuating salinity regime in Western Australia

1995 ◽  
Vol 46 (8) ◽  
pp. 1145 ◽  
Author(s):  
RJ Rippingale ◽  
SJ Kelly
Keyword(s):  
Western Australia ◽  
Deep Water ◽  
Surface Waters ◽  
Rapid Growth ◽  
Runoff Water ◽  
Salinity Regime ◽  
Low Salinity ◽  
Phyllorhiza Punctata

Although medusae of the scyphozoan Phyllorhiza punctata are abundant in the Swan-Canning estuary during summer, they are absent when surface waters are dominated by low-salinity runoff water following winter rains. In the laboratory, scyphistomae of P. punctata are shown to survive in conditions of temperature and salinity that occur in the estuary during winter in waters deeper than 5 m. It is postulated that areas of deep water provide a winter refuge for scyphistomae and that asexual production of both ciliary buds and ephyrae enables rapid growth of the P. punctata population in the spring of each year.

Chemical composition of some inland surface waters in South, Western and northeren Australia

1976 ◽  
Vol 27 (3) ◽  
pp. 379 ◽  
Author(s):  
WD Williams ◽  
RT Buckney
Keyword(s):  
Western Australia ◽  
Surface Waters ◽  
Major Ions ◽  
South Australia ◽  
Northern Australia ◽  
Low Salinity ◽  
South West ◽  
Yorke Peninsula ◽  
Standing Waters ◽  
Almost All

Numerous analyses of the major ions in surface waters of South Australia, south-western Western Australia, and northern Australia are presented and discussed. In South Australia three regions were investigated: the Yorke Peninsula, the Snowtown area, and the extreme south-east including the Coorong. In all three areas salinities were high, except for Lake Alexandrina and Lake Albert at the mouth of the River Murray, and sodium and chloride were the dominant ions. In rivers and standing waters in the south-west of Western Australia sodium and chloride were likewise the dominant ions. Almost all standing waters sampled in this region were saline and salinity was also high in some rivers investigated; there are, nevertheless, freshwater lakes and rivers of low salinity in this region. In running and standing waters of northern Australia, salinities were low and there was no consistent pattern of ionic dominance.

CO2-saturated Salinity Environment Effects on Ni-Mo Alloys at Gas Hydrate Formation Temperatures

2019 ◽  
Author(s):  
Christopher Ozigagu ◽  
Ting Zhou ◽  
Stephen Sanders ◽  
Teresa Golden
Keyword(s):  
Corrosion Resistance ◽  
Deep Water ◽  
Gas Hydrate ◽  
Surface Characterization ◽  
Oil And Gas ◽  
High Salinity ◽  
Hydrate Formation ◽  
Test Solution ◽  
Low Salinity ◽  
Gas Hydrate Formation

Corrosion and gas hydrate formation are flow assurance problems that can cause serious safety problems in deep water environments. One aspect that has been given less attention is the corrosion behavior of materials in salinity environment where gas hydrate formation and CO2 (sweet) corrosion can both occur. This type of environment is common in oil and gas deep water environments. The aim of this work is to investigate the effects of CO2-saturated salinity environment on Ni-Mo alloys at gas hydrate formation temperatures using electrochemical, SEM/EDX, and XRD surface characterization techniques. The immersion test solutions were sweet low-salinity (CO2 + 1 wt% salt + 5 oC) and sweet high- salinity (CO2 + ~24 wt% salt + 5 oC) environments, respectively. The as-deposited Ni-Mo alloy coating has the highest corrosion resistance of 33.28 kΩ cm2. The corrosion resistance dropped to 14.36 kΩ cm2 and 11.11 kΩ cm2 after 20 hrs of immersion in the sweet low-salinity and sweet high-salinity test solutions respectively. From grazing incidence XRD, the (111) reflection peak of the Ni-Mo coating was depressed and broaden after immersion in both test solutions due to increase in oxide layer formation on the surface of the Ni-Mo coating. SEM revealed a cracked surface morphology after immersion in sweet high-salinity test solution and elemental analysis shows the presence of oxygen after immersion in both test solutions. The oxygen content increased from 1.70 wt% after immersion in sweet low-salinity test solution to 2.37 wt% after immersion in sweet high-salinity test solution.

Groundwater oligochaetes show complex genetic patterns of distribution in the Pilbara region of Western Australia

2015 ◽  
Vol 29 (5) ◽  
pp. 405 ◽  
Author(s):  
Louise Brown ◽  
Terrie Finston ◽  
Garth Humphreys ◽  
Stefan Eberhard ◽  
Adrian Pinder
Keyword(s):  
Genetic Diversity ◽  
Western Australia ◽  
Surface Waters ◽  
Ecological Niches ◽  
Mitochondrial Coi ◽  
Groundwater Fauna ◽  
Ecological Requirements ◽  
Large Size ◽  
Geographic Patterns ◽  
Genetic Patterns

Patterns of genetic diversity in the groundwater fauna of Australia have largely focused on obligate stygobites of relatively large size, namely, crustaceans. Oligochaete worms, with their smaller size and broader ecological niches, provide a contrasting model in which to examine such patterns. Genetic diversity in subterranean oligochaetes in the Pilbara region of Western Australia were examined using one nuclear (18S) and two mitochondrial (COI, 12S) regions. The observed variation was assessed at three levels of hydrology – river basin, creek catchment, and individual bore or site – to document geographic patterns. Most species appeared to be restricted to an individual catchment; however, five species, representing three families, were widespread, with some haplotypes being shared between bores, catchments and even basins. General patterns suggest that while hydrology plays a role in the distribution of oligochaete species, it does not always confine them to catchments, in contrast to patterns observed in groundwater isopods and amphipods in the region. We suggest that intrinsic characteristics of oligochaetes, such as body size, shape, reproductive strategy and ecological requirements, may have allowed them greater dispersal within the subterranean biome of the Pilbara. In particular, oligochaetes may occupy subterranean and surface waters, increasing their opportunities for dispersal.

scholarly journals On the Linkage between Antarctic Surface Water Stratification and Global Deep-Water Temperature

2011 ◽  
Vol 24 (14) ◽  
pp. 3545-3557 ◽  
Author(s):  
Ralph F. Keeling ◽  
Martin Visbeck
Keyword(s):  
Water Temperature ◽  
North Atlantic ◽  
Deep Water ◽  
Surface Waters ◽  
Feedback Loop ◽  
Deep Ocean ◽  
Static Stability ◽  
Deep Waters ◽  
Water Stratification ◽  
The Antarctic

Abstract The suggestion is advanced that the remarkably low static stability of Antarctic surface waters may arise from a feedback loop involving global deep-water temperatures. If deep-water temperatures are too warm, this promotes Antarctic convection, thereby strengthening the inflow of Antarctic Bottom Water into the ocean interior and cooling the deep ocean. If deep waters are too cold, this promotes Antarctic stratification allowing the deep ocean to warm because of the input of North Atlantic Deep Water. A steady-state deep-water temperature is achieved such that the Antarctic surface can barely undergo convection. A two-box model is used to illustrate this feedback loop in its simplest expression and to develop basic concepts, such as the bounds on the operation of this loop. The model illustrates the possible dominating influence of Antarctic upwelling rate and Antarctic freshwater balance on global deep-water temperatures.

scholarly journals Stratification of surface waters during the last glacial millennial climatic events: a key factor in subsurface and deep-water mass dynamics

2015 ◽  
Vol 11 (11) ◽  
pp. 1507-1525 ◽  
Author(s):  
M. Wary ◽  
F. Eynaud ◽  
M. Sabine ◽  
S. Zaragosi ◽  
L. Rossignol ◽  
...  
Keyword(s):  
Deep Water ◽  
Surface Waters ◽  
High Surface ◽  
Hydrological Processes ◽  
Glacial Period ◽  
Last Glacial Period ◽  
Surface Conditions ◽  
Last Glacial ◽  
Deep Circulation ◽  
The Last Glacial

Abstract. The last glacial period was punctuated by abrupt climatic events with extrema known as Heinrich and Dansgaard–Oeschger events. These millennial events have been the subject of many paleoreconstructions and model experiments in the past decades, but yet the hydrological processes involved remain elusive. In the present work, high-resolution analyses were conducted on the 12–42 ka BP section of core MD99-2281 retrieved southwest of the Faeroe Islands, and combined with analyses conducted in two previous studies (Zumaque et al., 2012; Caulle et al., 2013). Such a multiproxy approach, coupling micropaleontological, geochemical and sedimentological analyses, allows us to track surface, subsurface, and deep hydrological processes occurring during these rapid climatic changes. Records indicate that the coldest episodes of the studied period (Greenland stadials and Heinrich stadials) were characterized by a strong stratification of surface waters. This surface stratification seems to have played a key role in the dynamics of subsurface and deep-water masses. Indeed, periods of high surface stratification are marked by a coupling of subsurface and deep circulations which sharply weaken at the beginning of stadials, while surface conditions progressively deteriorate throughout these cold episodes; conversely, periods of decreasing surface stratification (Greenland interstadials) are characterized by a coupling of surface and deep hydrological processes, with progressively milder surface conditions and gradual intensification of the deep circulation, while the vigor of the subsurface northward Atlantic flow remains constantly high. Our results also reveal different and atypical hydrological signatures during Heinrich stadials (HSs): while HS1 and HS4 exhibit a "usual" scheme with reduced overturning circulation, a relatively active North Atlantic circulation seems to have prevailed during HS2, and HS3 seems to have experienced a re-intensification of this circulation during the middle of the event. Our findings thus bring valuable information to better understand hydrological processes occurring in a key area during the abrupt climatic shifts of the last glacial period.

scholarly journals The depth distribution of recent marine Ostracoda from the southern Strait of Magellan

1997 ◽  
Vol 16 (2) ◽  
pp. 121-130 ◽  
Author(s):  
R. C. Whatley ◽  
M. Staunton ◽  
R. L. Kaesler
Keyword(s):  
Deep Water ◽  
Depth Distribution ◽  
Water Masses ◽  
Cold Temperature ◽  
Tierra Del Fuego ◽  
Sediment Samples ◽  
Low Salinity ◽  
Strait Of Magellan ◽  
The Strait Of Magellan

Abstract. From 16 sediment samples collected from the Chilean part of the Strait of Magellan, 2338 Ostracoda were recovered. These represent 61 species belonging to 45 genera and 16 families. Previous work in the Tierra del Fuego Province has shown the faunas to be highly endemic, resulting from the relative isolation of the region and its particular climatic and oceanographical characteristics. The fauna of the Strait of Magellan is similar to those previously described with one notable exception: the occurrence of deep-water, psychrospheric species at shallow depths. Species of Bradleya, Agrenocythere, Poseidonamicus, Bythoceratina, and Legitimocythere, usually recorded from bathyal to abyssal depths of more than 1000 m, were found together in the same samples with a typical, shelf fauna. Such unusual depth distribution of psychrospheric species may have resulted from the extremely cold temperature and low salinity of the water in the southern Strait of Magellan, coupled with the upwelling of cold, deep water masses.

Soil controls of phosphorus in runoff: Management barriers and opportunities

2011 ◽  
Vol 91 (3) ◽  
pp. 329-338 ◽  
Author(s):  
Peter Kleinman ◽  
Andrew Sharpley ◽  
Anthony Buda ◽  
Richard McDowell ◽  
Arthur Allen
Keyword(s):  
Water Quality ◽  
Surface Waters ◽  
Agricultural Soils ◽  
Soil Phosphorus ◽  
Short Term ◽  
Runoff Water ◽  
Sediment Delivery ◽  
Persistent Problem ◽  
Soil P ◽  
Barriers And Opportunities

Kleinman, P. J. A., Sharpley, A. N., Budda, A. R., McDowell, R. W. and Allen, A. L. 2011. Soil controls of phosphorus in runoff: Management barriers and opportunities. Can. J. Soil Sci. 91: 329–338. The persistent problem of eutrophication, the biological enrichment of surface waters, has produced a vast literature on soil phosphorus (P) effects on runoff water quality. This paper considers the mechanisms controlling soil P transfers from agricultural soils to runoff waters, and the management of these transfers. Historical emphases on soil conservation and control of sediment delivery to surface waters have demonstrated that comprehensive strategies to mitigate sediment-bound P transfer can produce long-term water quality improvements at a watershed scale. Less responsive are dissolved P releases from soils that have historically received P applications in excess of crop requirements. While halting further P applications to such soils may prevent dissolved P losses from growing, the desorption of P from soils that is derived from historical inputs, termed here as “legacy P”, can persist for long periods of time. Articulating the role of legacy P in delaying the response of watersheds to remedial programs requires more work, delivering the difficult message that yesterday's sinks of P may be today's sources. Even legacy sources of P that occur in low concentration relative to agronomic requirement can support significant loads of P in runoff under the right hydrologic conditions. Strategies that take advantage of the capacity of soils to buffer dissolved P losses, such as periodic tillage to diminish severe vertical stratification of P in no-till soils, offer short-term solutions to mitigating P losses. In some cases, more aggressive strategies are required to mitigate both short-term and legacy P losses.

scholarly journals ENVIRONMENTAL CONDITIONS OF THE WATERS OF THE MANZANARES RIVER, CUMANA-SUCRE, VENEZUELA

2016 ◽  
Author(s):  
Arístide Márquez ◽  
William James Senior ◽  
Gregorio Martínez ◽  
J. Castañeda
Keyword(s):  
Heavy Metals ◽  
Dissolved Oxygen ◽  
Surface Waters ◽  
Environmental Conditions ◽  
Dilution Effect ◽  
Volume Flow ◽  
Human Consumption ◽  
Suspended Material ◽  
Low Salinity ◽  
Total Ammonium

The Manzanares River is one of the more important rivers of Venezuela inasmuch as it is used to supply drinkingwater to a large part of the northeastern zone of Venezuela. For this reason a study was undertaken of the surface waters of theestuarine zone of the river, following the saline gradient from zero to salinities greater than 30. The following properties weremeasured: river volume flow, rainfall, pH, temperature, suspended materials, dissolved oxygen and ammonium, and heavy metals(Fe, Mn, Cu, Zn, Ni, Cr, Pb and Cd) in particulate and dissolved phases. River volume flow varied with seasonal rainfall throughoutthe year, as expected, while temperature varied between 24.5 and30.4 oC and pH ranged from 6.65 and 8.9. From the dry to the wetseason, suspended material increased from 23 to 880 mg/l at low salinity, and always decreased progressively as salinity increased.Concentrations of total ammonium, 14.5 to 14.3 mmol/l, were high, while those of dissolved oxygen, 3.57 to 5.27 ml/l, were low, andthese levels were even more accentuated at salinities under 5 during the dry season. The highest concentrations found for heavymetals were: Fe 406.02; Mn 5.57; Zn 2.18; Cu 0.72; Cr 0.19; Ni 0.72; Pb 0.12; Cd 0.03 mmol/l. These surpass Venezuelan legal limitsfor water intended for human consumption as well as for waters to be discharged in coastal areas. Concentrations decreased atincreased salinity because of the dilution effect, flocculation and/or precipitation in the form of oxyhydroxides. The results obtainedin this study reveal a serious deterioration of the state of the waters of the lower Manzanares river.

scholarly journals Chemical Quality of Surface Water of Bhola Sadar Upazila in Bangladesh for Irrigation, Aquaculture, Drinking and Livestock Consumption

2015 ◽  
Vol 6 (1) ◽  
pp. 131-140
Author(s):  
MF Karim ◽  
MW Zaman ◽  
R Sultana ◽  
MU Nizam ◽  
MR Kamruzzaman
Keyword(s):  
Surface Water ◽  
Surface Waters ◽  
Water Samples ◽  
Pond Water ◽  
Magnesium Content ◽  
Low Salinity ◽  
Quality Of Water ◽  
Hard Limit ◽  
Surface Water Samples

A study was carried out with 25 pond water samples of Bhola Sadar Upazila to assess the quality of surface water for irrigation, aquaculture, drinking and livestock consumption. Chemical analyses of different parameters were done to assess the quality of water. All of the water samples showed slightly acidic in nature. Sixteen surface water samples were not suitable for drinking and aquaculture in respect of pH (pH <6.5). Electrical conductivity (EC) categorized the waters as “low salinity” (C1) to “medium salinity” (C2) class for irrigation. With respect to total dissolved solids surface waters were within “highest desirable limit” for drinking and irrigation and suitable for livestock consumption and aquaculture. Calcium and Magnesium content rated the samples as “maximum permissible” and “highest desirable” limit for drinking. All the samples were suitable for drinking in case of Na and K, 21 samples were not suitable for aquaculture due to higher (>5.0 mg L-1) K content. Six samples were unsuitable for livestock due to higher (Cl >30mgL- 1) Cl values. SSP rated 9 samples as “good”, 1 as “excellent”, 6 as “doubtful” and 9 as “permissible” for irrigation. With respect to RSC 21 samples were “suitable”, 3 were “marginal” and 1 was “unsuitable” for irrigation. Hardness classified 14 samples within “moderately hard”, 10 within “soft” and only one as “hard” limit for irrigation and 1 sample (No. 16) was unsuitable for livestock consumption. P, B, Cu and As concentration categorized all the samples suitable for irrigation, aquaculture, drinking and livestock consumption.DOI: http://dx.doi.org/10.3329/jesnr.v6i1.22053 J. Environ. Sci. & Natural Resources, 6(1): 131-140 2013

scholarly journals Effect of water salinity on survival and osmotic level of larval (Zoea Stage) of mud crabs Scylla tranquebarica

2021 ◽  
Vol 890 (1) ◽  
pp. 012032
Author(s):  
Herlinah ◽  
Sulaeman ◽  
Gunarto ◽  
A Parenrengi ◽  
Rosmiati
Keyword(s):  
Glass Container ◽  
Water Salinity ◽  
Salinity Range ◽  
Asian Countries ◽  
Mud Crab ◽  
Salinity Regime ◽  
Optimal Salinity ◽  
Low Salinity ◽  
Effect Of Water ◽  
Crab Larvae

Abstract Mud crab of the genus Scylla are considered one of the most sought-after seafood today. This crab species has high quality and delicious aging growth rate and encourage expansion in the aquaculture sector especially in Southeast Asian Countries. However, salinity changes will cause changes in organisms osmotic pressure, and every aquatic biota has an optimal salinity range for survival. The study focuses on evaluating the effect of water salinity on the survival and osmotic levels of the purple mud crab, larvae of Scylla tranquebarica at the zoea stage. The LC50 assessment was performed in 10 different level of water salinity (0; 5; 10; 15; 20; 25; 30; 35, 40, and 50 ppt). Each treatment involved 20 ind./L of newly hatched crabs and being observed for 24 h in 10 different water salinity using 1 L volume glass container. The number of crab’s mortality were taken for each salinity regime. Larval behavior monitored during experiment. Meanwhile, the measurement of osmotic level was carried out at the salinity of 25, 30, and 35 ppt. The result shows that mud crab larvae exhibit any tolerance on the low salinity ranged from 0-10 ppt and the salinity of > 40 ppt. On the other hand, mud crab larvae were still able to survive at the salinity ranged from 20-40 ppt for more than 24 hours. The trend of the osmotic level of mud crab to survive is by hypo osmotic to iso osmotic.

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