scholarly journals Tolerance assessment of the aquatic invasive snail Potamopyrgus antipodarum to different post-dispersive conditions: implications for its invasive success

NeoBiota ◽  
2019 ◽  
Vol 44 ◽  
pp. 57-73 ◽  
Author(s):  
Alberto Romero-Blanco ◽  
Álvaro Alonso
Keyword(s):  
Aquatic Ecosystems ◽  
Exposure Period ◽  
High Water ◽  
Negative Consequences ◽  
Natural Conditions ◽  
Air Exposure ◽  
Abiotic Conditions ◽  
Normal Water ◽  
Chemical Conditions ◽  
Physical And Chemical

The New Zealand mudsnail (NZMS) Potamopyrgusantipodarum (Gray, 1843) (Tateidae, Mollusca) is a successful invasive species able to alter the functioning of the invaded ecosystems. However, to arrive and establish in new aquatic ecosystems, this snail must survive to the overland translocation through aerial exposure and must tolerate the new physical and chemical conditions of the recipient ecosystem. In this study, we simulated different conditions for the NZMS invasion by combining two air exposure treatments (0 and 20 h) with different physical and chemical conditions of the rehydration water (low and normal water temperatures and normal and high water conductivities). Mortality, behavior and neonate production were compared across treatments. Air exposure caused a high percentage of mortality but survivors tolerated the subsequent abiotic conditions. Low temperatures and high conductivities altered the behavior of adult snails, increasing significantly their reaction time (i.e. time to start normal movement). This may have negative consequences for the survival of this species under natural conditions. Finally, these conditions did not affect significantly the production of neonates. These results supported that the surviving NZMS to a brief period of air exposure possess the ability to acclimate to contrasting abiotic conditions with a potential establishment of new populations and that survivors can reproduce in different abiotic conditions after an air exposure period.

II. An Experiment in Marine Fish Cultivation: II. Some Physical and Chemical Conditions in a Fertilized Sea-loch (Loch Craiglin, Argyll)

1947 ◽  
Vol 63 (1) ◽  
pp. 3-20 ◽  
Author(s):  
A. P. Orr
Keyword(s):  
Marine Fish ◽  
Sea Water ◽  
Animal Production ◽  
Plant Production ◽  
Natural Conditions ◽  
Chemical Conditions ◽  
Physical And Chemical

The dependence of plant production in the sea on the presence of nutrient salts, especially nitrate and phosphate, and on illumination has been repeatedly demonstrated. The object of the present work was to find primarily whether, and to what degree, plant and animal production could be increased by adding fertilizers to an enclosed body of sea water under otherwise natural conditions.

scholarly journals Abundance and diversity of phytoplankton in the Paraná River (Argentina) 220 km downstream of the Yacyretá reservoir

2007 ◽  
Vol 67 (1) ◽  
pp. 53-63 ◽  
Author(s):  
Y. Zalocar de Domitrovic ◽  
ASG. Poi de Neiff ◽  
SL. Casco
Keyword(s):  
High Water ◽  
Paraná River ◽  
Cylindrospermopsis Raciborskii ◽  
Left Bank ◽  
Parana River ◽  
Paraguay River ◽  
Abundance And Diversity ◽  
Chemical Conditions ◽  
The Right ◽  
Physical And Chemical

Patterns in the temporal composition, abundance and diversity of the phytoplankton community of the Paraná river prior to and after the initial filling phase of the Yacyretá reservoir are analyzed. The study site is located 220 km downstream from the Yacyretá reservoir and 30 km downstream from the confluence with the Paraguay river. Because both rivers remain separate and unmixed at the study site, we compared the possible effects of the impoundment on both river banks (left and right banks) in hydrological periods with similar duration and magnitude of the low and high water phases. Physical and chemical conditions measured on the right bank (water from the Paraguay river) were similar at both periods (pre and post-impoundment) whereas conductivity, pH and orthophosphate concentration increased on the left bank (water from the High Paraná river and Yacyretá reservoir) after the impoundment. Changes in phytoplankton density and diversity were observed only in samples collected from water flowing from the reservoir (left bank). The density of Chlorophyceae (Chloromonas acidophila, Chlamydomonas leptobasis, Choricystis minor, Chlorella vulgaris, Scenedesmus ecornis, Monoraphidium minutum, M. contortum and M. pusillum) and Cryptophyceae (Rhodomonas minuta, Cryptomonas marssonii and C. ovata) increased while Cyanophyceae (Cylindrospermopsis raciborskii, Raphidiopsis mediterranea and Planktolyngbya subtilis) and Bacillariophyceae (Aulacoseira granulata and its bioforms) decreased compared to previous studies conducted on the left bank of the Paraná river. Phytoplankton collected from the right bank of the river did not differ in pre and post- impoundment samples because they originate from the Paraguay river, which remains relatively unaffected by human activities.

Permeability to albumin in isolated coronary venules

1993 ◽  
Vol 265 (2) ◽  
pp. H543-H552 ◽  
Author(s):  
Y. Yuan ◽  
W. M. Chilian ◽  
H. J. Granger ◽  
D. C. Zawieja
Keyword(s):  
Permeability Coefficient ◽  
Filtration Rate ◽  
Intraluminal Pressure ◽  
Apparent Permeability ◽  
Filtration Pressure ◽  
Diffusive Permeability ◽  
Apparent Permeability Coefficient ◽  
Chemical Conditions ◽  
Physical And Chemical ◽  
Intravascular Pressure

This study reports measurements of albumin permeability in isolated coronary venules. The isolated microvessel technique allows the quantification of transmural exchange of macromolecules under tightly controlled physical and chemical conditions. Transvenular exchange of albumin was studied in isolated coronary venules during alterations in filtration rate caused by changes in intravascular pressure. The apparent permeability coefficient of albumin (Pa) at an intraluminal pressure of 11 cmH2O was 3.92 +/- 0.43 x 10(-6) cm/s. Elevating intraluminal pressure to 16 and 21 cmH2O increased Pa to 5.13 +/- 0.57 x 10(-6) and 6.78 +/- 0.66 x 10(-6) cm/s, respectively. Calculation of the true diffusive permeability coefficient of albumin (Pd) at zero filtration rate was 1.54 x 10(-6) cm/s. The product of hydraulic conductance (Lp) and (1 - sigma), where sigma is the solute reflection coefficient, was 3.25 x 10(-7) cm.s-1 x cmH2O-1. At a net filtration pressure of 4-5 cmH2O, diffusion accounts for > 60% of total albumin transport across the venular wall. Transmural albumin flux is very sensitive to filtration rate, rising 6.7% for each cmH2O elevation of net filtration pressure. At 11 cmH2O net filtration pressure, convection accounts for nearly 70% of net albumin extravasation from the venular lumen. We suggest that the isolated coronary venule is a suitable preparation for the study of solute exchange in the heart.

scholarly journals Origin of Life on Mars: Suitability and Opportunities

Life ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 539
Author(s):  
Benton C. Clark ◽  
Vera M. Kolb ◽  
Andrew Steele ◽  
Christopher H. House ◽  
Nina L. Lanza ◽  
...  
Keyword(s):  
Origin Of Life ◽  
Energy Sources ◽  
Early Earth ◽  
Sediment Samples ◽  
Life On Mars ◽  
Eventual Return ◽  
History Of ◽  
Early Mars ◽  
Chemical Conditions ◽  
Physical And Chemical

Although the habitability of early Mars is now well established, its suitability for conditions favorable to an independent origin of life (OoL) has been less certain. With continued exploration, evidence has mounted for a widespread diversity of physical and chemical conditions on Mars that mimic those variously hypothesized as settings in which life first arose on Earth. Mars has also provided water, energy sources, CHNOPS elements, critical catalytic transition metal elements, as well as B, Mg, Ca, Na and K, all of which are elements associated with life as we know it. With its highly favorable sulfur abundance and land/ocean ratio, early wet Mars remains a prime candidate for its own OoL, in many respects superior to Earth. The relatively well-preserved ancient surface of planet Mars helps inform the range of possible analogous conditions during the now-obliterated history of early Earth. Continued exploration of Mars also contributes to the understanding of the opportunities for settings enabling an OoL on exoplanets. Favoring geochemical sediment samples for eventual return to Earth will enhance assessments of the likelihood of a Martian OoL.

scholarly journals STRUKTUR KOMUNITAS ZOOPLANKTON DI PERAIRAN KABUPATEN LOMBOK UTARA, PROVINSI NUSA TENGGARA BARAT

2018 ◽  
Vol 18 (2) ◽  
Author(s):  
Muhammad Junaidi ◽  
Nurliah Nurliah ◽  
Fariq Azhar
Keyword(s):  
Water Quality ◽  
Community Structure ◽  
Aquatic Ecosystems ◽  
Zooplankton Community ◽  
Geographical Information ◽  
Zooplankton Community Structure ◽  
Ecological Index ◽  
Physical Chemical ◽  
Chemical Conditions

ABSTRAKMengingat peranan zooplankton dalam ekosistem perairan sangat penting, maka dilakukan penelitian dengan tujuan untuk menganalisis struktur komunitas zooplankton yang meliputi jenis, kelimpahan, dan indek ekologi, dan  kaitan  distribusi zooplankton dan kualitas perairan di Perairan Kabupaten Lombok Utara. Pengumpulan data dirancang dengan sistem informasi geografis (SIG) pada 23 stasiun pengamatan yang ditentukan dengan teknik acak sederhana.  Hasil penelitian menunjukkan bahwa jenis dan kelimpahan zooplankton yang ditemukan di Perairan Kabupaten Lombok Utara cukup bervariasi dengan jumlah genus  sebanyak 9 yang terbagi  dari  5 kelas.  Berdasarkan perhitungan indeks ekologi menunjukkan bahwa struktur  komunitas zooplankton dalam kategori perairan yang kurang stabil. Kelimpahan dan indeks ekologi zooplankton  dipengaruhi oleh kondisi lingkungan (fisik-kimia) perairan antara lain  kecerahan, pH dan oksigen terlarut. Kata kunci : zooplankton,  struktur komunitas, kualitas perairan, kelimpahanABSTRACTConsidering that the role of zooplankton in aquatic ecosystems is very  important, research is carried out with the aim of analyzing zooplankton community structure which includes the type, abundance, and ecological index, and the relation of zooplankton distribution and water quality in North Lombok Regency Waters. Data collection was designed with a geographical information system (GIS) on 23 observation stations that were determined by simple random techniques. he results of this study indicate that the type and abundance of zooplankton found in the waters of North Lombok Regency are quite varied with the number of genus as many as 9 which are divided into 5 classes. Based on the calculation of the ecological index shows that the zooplankton community structure is in the category of less stable waters. The abundance and ecological index of zooplankton is influenced by the environmental (physical-chemical) conditions of the waters including brightness, pH and dissolved oxygen. Keywords: zooplankton, community structure, water quality, abundance 

scholarly journals THE ISSUE OF APPLICATION OF PHYSICAL AND CHEMICAL TECHNOLOGIES IN THE DEVELOPMENT OF OIL AND GAS FIELDS

2016 ◽  
pp. 71-74
Author(s):  
E. F. Zakharova ◽  
E. V. Levanova ◽  
G. N. Farkhutdinov
Keyword(s):  
Oil And Gas ◽  
High Water ◽  
Oil Fields ◽  
Chemical Methods ◽  
Oil And Gas Fields ◽  
Extraction Factor ◽  
High Water Cut ◽  
Water Cut ◽  
Gas Fields ◽  
Physical And Chemical

The efficiency of different physical and chemical technologies used in various areas and Romashkinskoye New-Elkhovskoye oil fields was researched. The result was a conclusion that at high water-cut objects, restriction of movement of water in highly permeable leached zones of a productive layer is one of the main conditions for increasing the efficiency of not only flooding, but also the use of physical and chemical methods based on improving of oil extraction factor.

scholarly journals Ekosistem Mangrove Binuangeun, Banten: Kondisi Fisik Dan Kimia Serta Ragam Ikan

2020 ◽  
Vol 5 (2) ◽  
pp. 32-40
Author(s):  
Fitri Andriyani
Keyword(s):  
Research Method ◽  
Mangrove Ecosystem ◽  
Water Current ◽  
Root Structure ◽  
Chemical Condition ◽  
Literature Study ◽  
Marine Animals ◽  
Mangrove Ecosystems ◽  
Chemical Conditions ◽  
Physical And Chemical

Binuangeun Mangrove Ecosystem is located in the south western Java Island, in the area of ​​Lebak Regency, Banten Province. Mangrove ecosystems are ecosystems that located at the Coastal areas which are a habitat for a variety of marine animals which are associated with it, mostly fish, because of its complex or a very effective root structure which can provide a place for fish to be able to live, take shelter, develop, breed and also look for food. This research was conducted to determine the physical and chemical condition and the variety of fishes which found in the Binuangeu, Banten Mangrove Ecosystem. This research method uses literature study. Physical and chemical conditions of the Binuangeun Mangrove Ecosystem, Banten have degrees of temperature ranging from 28.20 - 32.20; acidity range between 7.00 - 8.09; turbidity ranges from 22.50 - 76.00 NTU; water current ranged from 0.079 to 0.189; phosphate content ranges from 0.02 - 0.008; salinity ranges from 30-35 PSU; and dissolved oxygen content ranges from 5.67 - 8.70. The types of fish found in the Binuangeun Mangrove Ecosystem, Banten are 45 species from 22 Family. The most abundant and relatively high species of existence is the Gobiidae with 10 species.   Keywords: Banten, Binuangeun, Ecosystems, Fish, Mangroves

Temperature effects on bank filtration: redox conditions and physical-chemical parameters of pore water at Lake Tegel, Berlin, Germany

2010 ◽  
Vol 1 (1) ◽  
pp. 55-66 ◽  
Author(s):  
A. Gross-Wittke ◽  
G. Gunkel ◽  
A. Hoffmann
Keyword(s):  
Water Temperature ◽  
High Water ◽  
Nitrate Respiration ◽  
Redox Processes ◽  
Redox Potentials ◽  
Bank Filtration ◽  
Physical Chemical ◽  
Drinking Water Production ◽  
Chemical Conditions ◽  
Sediment Layers

In the city of Berlin, artificial groundwater recharge techniques, such as bank filtration and infiltration ponds, are an important source for drinking water production. Climate change with increasing surface water temperatures can influence the water purification processes during bank filtration mainly due the intensification of metabolic processes leading to a decrease of oxygen and an increase of anaerobic conditions. In Lake Tegel a significant increase of water temperature in the epilimnion of 2.4°C within the last 30 years was recorded. For a better understanding of induced bank filtration at Lake Tegel, redox processes and physical-chemical conditions within the surface sediment layers (0–26 cm depth) at the littoral infiltration zone were investigated. The influence of temperature in the range of 0–25°C on microbial catalysis of redox processes, such as reduction of nitrate and sulphate, was examined during the period March 2004–June 2005. High water temperatures (16–25°C) were accompanied by negative redox potentials (EH=−47 mV) and decreasing Ninorg concentrations, while the amount of ammonia, Mn2 +  and Fe2 +  was rising. This indicates redox processes such as denitrification, Mn4 +  reduction, nitrate respiration and ammonification, as well as Fe3 +  reduction. The reduction of sulphate, however, has not yet become significant at Lake Tegel, but with increasing water temperature, sulphate reduction must be expected.

Sign in / Sign up

Export Citation Format

Share Document