scholarly journals Changes in the aquatic moss Sphagnum denticulatum Brid. population abundance in a softwater lake over a period of three years

2011 ◽  
Vol 79 (2) ◽  
pp. 167-173 ◽  
Author(s):  
Józef Szmeja
Keyword(s):  
Water Temperature ◽  
Green Algae ◽  
Algal Bloom ◽  
Population Abundance ◽  
Aquatic Moss ◽  
The Third ◽  
Filamentous Green Algae ◽  
Water Ph ◽  
Second Year ◽  
Sediment Ph

Changes in population abundance of submerged <em>Sphagnum denticulatum</em> Brid. were studied in an acidic and oligotrophic lake in NW Poland over three years. Individuals were counted in a moss carpet at a depth of 2.5 m on 4 experimental plots, 1 × 1 m each, every 30 days for 36 months using the SCUBA method. PAR intensity was seasonally variable (in winter higher than in summer). Changes in water pH, conductivity, HCO<sub>3</sub><sup>-</sup> concentration, hydration and sediment pH were statistically insignificant (p &gt; 0.05). In the summer of the second study year the moss carpet disappeared almost completely due to a massive bloom of filamentous green algae. Periods of growth, regression and regeneration were observed in the population. The stabilisation of population size took 24 months and followed the pattern: slight fluctuations, then rapid growth and repetition of slight fluctuations. The first stage lasted nine, the second four and the third nine months. These stages took place irrespective of seasons, temperature or PAR intensity. Each rapid increase in abundance lasted about 30 days, at PAR intensity &gt;20% and water temperature ranging from 11 to 16<sup>o</sup>C (in winter, spring or autumn). The regression stage brought about by the algal bloom started in the second year (in summer) and lasted six months (until the end of January in the third year). The population regeneration began in winter (in February, water temperature 3.0<sup>o</sup>C, PAR about 20%, ice cover 0.15 m) and finished with the end of spring. The population of <em>S. denticulatum</em> shows a repetitive pattern of abundance variations, which is seriously disturbed in summer, especially after a warm spring, by a massive bloom of filamentous green algae.

Growth characteristics of bloom-forming filamentous green algae in the littoral zone of an experimentally acidified lake

1995 ◽  
Vol 52 (10) ◽  
pp. 2251-2263 ◽  
Author(s):  
Michael A. Turner ◽  
Leif J. Sigurdson ◽  
David L. Findlay ◽  
E. Todd Howell ◽  
Gordon G. C. Robinson ◽  
...  
Keyword(s):  
Water Temperature ◽  
Green Algae ◽  
Inorganic Carbon ◽  
Dissolved Inorganic Carbon ◽  
Benthic Algae ◽  
Growth Characteristics ◽  
Experimental Lakes Area ◽  
Filamentous Green Algae ◽  
High Photosynthetic Capacity ◽  
Major Factors

Filamentous green algae, predominantly Mougeotia and Zygogonium, bloom frequently in the littoral zones of acidified lakes. Growth characteristics of Zygogonium-dominated filamentous green algae were studied for 4 yr in an experimentally acidified (pH 4.5) lake at the Experimental Lakes Area of northwestern Ontario. They were present in low abundance as periphyton (algal associations attached to surfaces) during spring, and as blooms of metaphyton (benthic algae unconstrained by surfaces) beginning in midsummer and reaching a maximum in early fall. Metaphytic filamentous green algae displayed high photosynthetic capacity in summer despite the oligotrophic nature of the acidified lake. The major factors controlling photosynthetic rates of Zygogonium were similar to those controlling Mougeotia, and included algal crowding, irradiance, dissolved inorganic carbon, and water temperature. Rates of photosynthesis were negatively dependent upon algal crowding, so that highest rates were associated with minimum algal crowding. Light requirements for photosynthesis were higher than those of the epilithon, which were dominant prior to acidification. The dependence of photosynthesis on ambient concentrations of dissolved inorganic carbon was partly regulated by water temperature. Anthropogenically caused releases from growth limitations (e.g., increased availability of limiting nutrients, increased water temperature, and extension of the growing season) may cause proliferation of filamentous green algae in the future.

Bonding Social Capital, Afghan Refugees, and Early Access to Employment

2021 ◽  
pp. 019791832110002
Author(s):  
Matteo Vergani ◽  
Ihsan Yilmaz ◽  
Greg Barton ◽  
James Barry ◽  
Galib Bashirov ◽  
...  
Keyword(s):  
Social Capital ◽  
Migration Policy ◽  
Research Note ◽  
Bonding Social Capital ◽  
Afghan Refugees ◽  
Employment Success ◽  
The Third ◽  
Early Access ◽  
Second Year ◽  
The Impact

This IMR Research Note examines the impact of the level of bonding social capital on access to employment among newly arrived Afghan refugees in Victoria (Australia). Based on a mixed-methods analysis of biographical interviews with 80 Afghan refugees, it examines their use of social capital, year by year, during the first three years after their arrival. Our analysis shows that higher levels of bonding social capital are associated with greater success in finding employment during the first and second year of settlement. In the third year, however, bonding social capital for Afghan refugees in Victoria is no longer a significant predictor of employment. This Research Note helps clarify inconsistent findings in the literature on the effects of social capital on obtaining employment by suggesting that bonding social capital’s impact on refugee employment success changes significantly across the first three years after arrival. This finding has important implications for migration policy and the prioritization of resources toward services for newly arrived refugees.

scholarly journals AB0751 SAFETY AND PERSISTENCE OF USTEKINUMAB IN PATIENTS WITH PSORIATIC ARTHRITIS IN BIOBADASER

2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 1672.2-1672
Author(s):  
N. Busquets-Pérez ◽  
C. Sánchez-Piedra ◽  
P. Vela-Casasempere ◽  
M. Freire-Gonzalez ◽  
C. Bohórquez ◽  
...  
Keyword(s):  
Psoriatic Arthritis ◽  
Adverse Events ◽  
First Year ◽  
Line Treatment ◽  
Minimal Disease Activity ◽  
First Line ◽  
The Third ◽  
Minimal Disease ◽  
Second Year ◽  
Third Line

Background:Ustekinumab has been efficacy and safety for psoriatic artritis in clinical trials.Objectives:To assess effectiveness, by means of drug persistence analisys, and safety of ustekinumab in patients with psoriastic arthritis in Biobadaser.Methods:BIOBADASER is the Spanish registry of biological drugs of the Spanish Society of Rheumatology and the Spanish Medicines Agency. We identified patients aged 18 years or more with psoriatic arthritis on Ustekinumab. A descriptive analysis was performed.The persistence of ustekinumab therapy was calculated with a Kaplan-Meier curve and was compared with the persistence of anti-TNF, according to line treatment. Log Rank test was used to establish a comparison. Adverse events occurring with ustekinumab are described according to year treatment.Results:One hundred and twelve patients were on ustekinumab. Most of them were on their second or third line treatment: 53.57% more than one biological therapy (BT), 19.64% second BT, 26.79% were naïve for BT. Most of them were on 45 mg dose: 88.24%. Median duration of disease at Ustekinumab initiation was 10.1 SD 7.2 years; 69.23% had peripheral arthritis; 45.24% had obesity and 39.29% were overweight; 40,6% were on prednisone and 59.82% on DMARD. The cause of discontinuation of treatment was mainly inefficacy (82.61%) and less common an adverse event (6.52%). The probability of persistence of treatment with ustekinumab was 0.83 (95% CI 0.63-0.92) at year 1, 0.79 (0.58-0.90) at year 2 and 0.79 (0.58-0.9) at year 3 when ustekinumab was prescribed as the first line treatment. The persistence decrease when ustekinumab was prescribe as a second and third treatment: being 0.53 (0.27-0.73) the first year, 0.46 (0.22-0.67) the second year and 0.46 (0.22-0.67) as a second line treatment and 0.58 (0.44-0.70) the first year, 0.33 (0.17-0.50) the second year and 0.33 (0.17-0.50) the third year as a third line treatment.The persistence was similar to anti-TNF treatment, according to line treatment. Adverse events were mainly mild (97.83%) and occurred the first year of treatment. Most of the adverse events were classified as “infections and infestations” (36.96%).Conclusion:The persistence of ustekinumab was high, being 83% at the end of the first year on treatment and 79% the second and the third year of treatment. The persistence of ustekinumab was higher when if it was the first line treatment compared as if it was used as the second o third BT option. The persistence of Ustekinumab is similar to the persistence of anti-TNF treatments in all the analyzed treatment lines (no statistically differences were found). Adverse events occurred mainly during the first year treatment. They were mainly mild adverse events and the frequency decreased within the second and third year of treatment.References:[1]Treatment with ustekinumab in a Spanish cohort of patients with psoriasis and psoriatic arthritis in daily clinical practice.Almirall M, Rodriguez J, Mateo L, Carrascosa JM, Notario J, Gallardo F. Clin Rheumatol. 2017 Feb;36(2):439-443;[2]Minimal disease activity in patients with psoriatic arthritis treated with ustekinumab: results from a 24-week real-world study.Napolitano M, Costa L, Caso F, Megna M, Scarpa R, Balato N, Ayala F, Balato A. J Clin Rheumatol. 2018 Oct;24(7):381-384;[3]Minimal Disease Activity and Patient-Acceptable Symptom State in Psoriatic Arthritis: A Real-World Evidence Study With Ustekinumab.Queiro R, Brandy A, Rosado MC, Lorenzo A, Coto P, Carriles C, Alperi M, Ballina J. Actas Dermosifiliogr. 2018 Jun 28;[4]An analysis of Drug Survival, Effectiveness, and Safety in Moderate to Severe Psoriasis Treated With Ustekinumab: An Observational Study of 69 Patients in Routine Clinical Practice.Salgüero Fernández I, Gil MH, Sanz MS, Gullón GR;Disclosure of Interests:None declared

scholarly journals Trends and abrupt changes in 104 years of ice cover and water temperature in a dimictic lake in response to air temperature, wind speed, and water clarity drivers

2016 ◽  
Vol 20 (5) ◽  
pp. 1681-1702 ◽  
Author(s):  
Madeline R. Magee ◽  
Chin H. Wu ◽  
Dale M. Robertson ◽  
Richard C. Lathrop ◽  
David P. Hamilton
Keyword(s):  
Wind Speed ◽  
Water Temperature ◽  
Air Temperature ◽  
Water Clarity ◽  
Ice Cover ◽  
Ice Thickness ◽  
Lake Mendota ◽  
The Third ◽  
Abrupt Changes ◽  
Hypolimnetic Heating

Abstract. The one-dimensional hydrodynamic ice model, DYRESM-WQ-I, was modified to simulate ice cover and thermal structure of dimictic Lake Mendota, Wisconsin, USA, over a continuous 104-year period (1911–2014). The model results were then used to examine the drivers of changes in ice cover and water temperature, focusing on the responses to shifts in air temperature, wind speed, and water clarity at multiyear timescales. Observations of the drivers include a change in the trend of warming air temperatures from 0.081 °C per decade before 1981 to 0.334 °C per decade thereafter, as well as a shift in mean wind speed from 4.44 m s−1 before 1994 to 3.74 m s−1 thereafter. Observations show that Lake Mendota has experienced significant changes in ice cover: later ice-on date(9.0 days later per century), earlier ice-off date (12.3 days per century), decreasing ice cover duration (21.3 days per century), while model simulations indicate a change in maximum ice thickness (12.7 cm decrease per century). Model simulations also show changes in the lake thermal regime of earlier stratification onset (12.3 days per century), later fall turnover (14.6 days per century), longer stratification duration (26.8 days per century), and decreasing summer hypolimnetic temperatures (−1.4 °C per century). Correlation analysis of lake variables and driving variables revealed ice cover variables, stratification onset, epilimnetic temperature, and hypolimnetic temperature were most closely correlated with air temperature, whereas freeze-over water temperature, hypolimnetic heating, and fall turnover date were more closely correlated with wind speed. Each lake variable (i.e., ice-on and ice-off dates, ice cover duration, maximum ice thickness, freeze-over water temperature, stratification onset, fall turnover date, stratification duration, epilimnion temperature, hypolimnion temperature, and hypolimnetic heating) was averaged for the three periods (1911–1980, 1981–1993, and 1994–2014) delineated by abrupt changes in air temperature and wind speed. Average summer hypolimnetic temperature and fall turnover date exhibit significant differences between the third period and the first two periods. Changes in ice cover (ice-on and ice-off dates, ice cover duration, and maximum ice thickness) exhibit an abrupt change after 1994, which was related in part to the warm El Niño winter of 1997–1998. Under-ice water temperature, freeze-over water temperature, hypolimnetic temperature, fall turnover date, and stratification duration demonstrate a significant difference in the third period (1994–2014), when air temperature was warmest and wind speeds decreased rather abruptly. The trends in ice cover and water temperature demonstrate responses to both long-term and abrupt changes in meteorological conditions that can be complemented with numerical modeling to better understand how these variables will respond in a future climate.

scholarly journals Interaction between simulated dense Scenedesmus dimorphus (Chlorophyta) bloom and freshwater meta-zooplankton community

2018 ◽  
Vol 77 (2) ◽  
Author(s):  
Zengling Ma ◽  
Hengguo Yu ◽  
Ronald Thring ◽  
Chuanjun Dai ◽  
Anglv Shen ◽  
...  
Keyword(s):  
Community Structure ◽  
Green Algae ◽  
Aquatic Ecosystems ◽  
Algal Blooms ◽  
Algal Bloom ◽  
Photochemical Efficiency ◽  
Zooplankton Community ◽  
Post Inoculation ◽  
Zooplankton Community Structure ◽  
Scenedesmus Dimorphus

Algal bloom has been a subject of much research, especially the occurrence of blue-green algae (cyanobacteria) blooms and their effects on aquatic ecosystems. However, the interaction between green algae blooms and zooplankton community was rarely investigated. In the present study, the effects exerted by Scenedesmus dimorphus (green alga) bloom on the community structure of zooplankton and the top-down control of the bloom process mediated by the zooplankton were evaluated using a series of laboratory cultures. The results showed that a dense S. dimorphus bloom could change the zooplankton community structure by decreasing its diversity indices, leading to the enrichment of a particular zooplankton species, Brachionus calyciflorus. In the presence of mixed species of zooplankton, the density of S. dimorphus in the culture was decreased as determined by a change in total chlorophyll a (Chl a) concentration, which was about 200 μg L-1 lower than that of the zooplankton-free culture. Furthermore, the number of species belonging to Cladocera, Copepoda and Rotifera all decreased, with all the cladocerans disappeared in the co-culture within 2 weeks of culturing, while the density of rotifers increased from 818 (±243) ind L-1 at the time of inoculation to 40733 (±2173) ind L-1 on the 14th day post-inoculation. Grazing of S. dimorphus by the rotifer B. calyciflorus neutralized its growth, and the gradual increase in B. calyciflorus density eventually led to the collapse of the bloom. Furthermore, grazing by B. calyciflorus also led to a decrease in the maximal photochemical efficiency (Fv/Fm) of photosystem II (PSII). The combined changes occurring in the zooplankton community structure during the process of S. dimorphus bloom and the negative effects of grazing on algal growth, morphology and photosynthetic activities confirmed the key role of zooplankton in the control of algal bloom. The results of the study therefore indicated that dense algal blooms caused by non-toxic algae could still remain a threat to aquatic ecosystems.

scholarly journals Urban mosquitoes and filamentous green algae: their biomonitoring role in heavy metal pollution in open wastewater channels in Nairobi, Kenya

2021 ◽  
Author(s):  
Geoffrey Kariuki Kinuthia ◽  
Veronica Ngure ◽  
Luna Kamau
Keyword(s):  
Heavy Metals ◽  
Green Algae ◽  
Toxic Elements ◽  
Tap Water ◽  
Aquatic Organisms ◽  
Industrial Area ◽  
Metal Exposure ◽  
Water Control ◽  
Filamentous Green Algae ◽  
Us Epa

Abstract Background Levels of Mercury (Hg), Lead (Pb), Chromium (Cr), Cadmium (Cd), Thallium (Tl), and Nickel (Ni) in samples of wastewater, filamentous green algae (spirogyra) and urban mosquitoes obtained from open wastewater channels in Nairobi industrial area, Kenya, was established. Industrial wastewater may contain hazardous heavy metals upon exposure. Aquatic organisms in wastewater may accumulate the toxic elements with time. Therefore, human population living in informal settlements in Nairobi industrial area risk exposure to such toxic elements. Biomonitoring using aquatic organisms can be key in metal exposure assessment. Results Pb, Cr, & Ni levels ranged from 3.08 to 15.31 µg/L while Tl, Hg, & Cd levels ranged from 0.05 to 0.12 µg/L in wastewater. Pb, Cr, Ni, & Cd levels were above WHO, Kenya & US EPA limits for wastewater but Hg was not. Metals in tap water (control) which ranged from 0.01 to 0.2 µg/L was below WHO, US EPA, & Kenya standard limits. Pb, Cr, Tl, & Ni levels in assorted field mosquitoes were 1.3 to 2.4 times higher than in assorted laboratory-reared mosquitoes. Hg & Cd concentrations in laboratory-reared mosquitoes (0.26 mg/L & 1.8 mg/L respectively) was higher than in field mosquitoes (0.048 mg/L & 0.12 mg/L respectively). Pb, Cr, Ni, & Cd levels in green filamentous algae were 110.62, 29.75, 14.45, & 0.44 mg/L respectively and above WHO limits for vegetable plants. Hg level in algae samples (0.057 mg/L) was below WHO standard limits but above Kenya & US EPA limits in vegetables. Correlations for Pb & Hg (r = 0.957; P < 0.05); Cd & Cr (r = 0.985; P < 0.05) in algae samples were noted. The metal concentrations in the samples were in the order, wastewater < mosquitoes < filamentous green algae. Conclusion Samples of wastewater, mosquitoes and filamentous green algae from open wastewater channels and immediate vicinity, in Nairobi industrial area (Kenya) contained Hg, Pb, Cr, Cd, Tl, and Ni. Urban mosquitoes and filamentous green algae can play a role of metal biomonitoring in wastewater. The possibility of urban mosquitoes transferring the heavy metals to their hosts when sucking blood should be investigated.

scholarly journals ANÁLISIS DEL CRECIMIENTO Y LA MORTALIDAD DE ANISOTREMUS INTERRUPTUS (GILL) (PERCIFORMES: HAEMULIDAE) EN LA COSTA DE COLIMA, MÉXICO

2016 ◽  
Vol 33 ◽  
Author(s):  
Elaine Espino Barr ◽  
Manuel Gallardo Cabello ◽  
Fernando González Orozco ◽  
Arturo Garcia Boa
Keyword(s):  
Mortality Rate ◽  
Growth Parameters ◽  
Total Mortality ◽  
Condition Index ◽  
First Year ◽  
The Third ◽  
Second Year ◽  
First Year Of Life ◽  
Mortality Analysis

This paper deals with the growth and mortality analysis of the burrito grunt A n i s o t remus interru p t u s on the coast of Colima, México. The estimated growth parameters are: L¥ = 50.59 cm; W¥ = 5,051.04 g; k = 0.147 years- 1; to = -0.916 years; A0 . 9 5 = 19.46 years. Most of the growth occurred during the first year of life, when the grunt grows 12.52 cm, the second year it grows 4.95 cm and the third, 4.60 cm. The highest value of the condition index took place between February and September. The total mortality rate (Z) was calculated as 0.53 years- 1. These values are basic for the plan of administration of the fishery of this species.

scholarly journals RANCANG BANGUN ALAT UKUR SISTEM MONITORING pH, TEMPERATUR, DAN KELEMBAPAN AKUARIUM IKAN HIAS BERBASIS ARDUINO UNO

2021 ◽  
Vol 10 (1) ◽  
pp. 1
Author(s):  
Bintara Putra Candra Bareta ◽  
Alex Harijanto ◽  
Maryani Maryani
Keyword(s):  
Water Quality ◽  
Water Temperature ◽  
Physics Education ◽  
Ornamental Fish ◽  
Fish Growth ◽  
Design System ◽  
Sensor Calibration ◽  
Measuring Instruments ◽  
Water Ph ◽  
Arduino Uno

Water quality in the process of ornamental fish cultivation plays an important role in creating an environment of life that is in accordance with the needs of ornamental fish. Acidity (pH) and water temperature are one of the important factors of ornamental fish growth. The purpose of this study is to describe how the design system builds arduino-based humidity and pH temperature measuring instruments. Review the validity of moisture temperature and water pH. Monitor the humidity temperature and pH of ornamental fish aquarium water to know the results of the same data with liturgy. This research is a research and development research, conducted in the Laboratory of Physics Education Study FKIP Jember University. The research time was carried out for four months. The samples used in this study were ornamental carp. Based on the analysis of data obtained, it can be concluded that, (1) The work of pH, temperature, and spouting systems based on Arduino Uno is made with sen0161-V2, DS18B20 and DHT-11 sensors and data appearance media namely LCD. (2) Rakaian system is then calibrated to state that the system can be used properly. Calibration includes Arduino-based pH, temperature and Humidity sensor calibration as well as LCD testing. (3) The data that has been found by the researcher and the data in the literature has a match.   Keywords: water quality, Acidity (pH), water temperature, arduino-based.

scholarly journals An Environmental Study on Phytoplankton (Diatoms) in Al-Yusifiya River, Iraq

2014 ◽  
Vol 11 (3) ◽  
pp. 1301-1309
Author(s):  
Baghdad Science Journal
Keyword(s):  
Dissolved Oxygen ◽  
Water Temperature ◽  
Electric Conductivity ◽  
Physicochemical Parameters ◽  
Environmental Study ◽  
Euphrates River ◽  
The Third ◽  
Centric Diatoms

An environmental study conducted on diatoms in Al Yusifiya river beyond its branching from Euphrates river. Four sites were selected along the river for the period from march 2013 to September 2013. The present study involved the measurement of physicochemical parameters, also the qualitative and quantities of diatoms. The studied parameters values ranged as follows: 19-44Cº and 16-30 Cº for air and water temperature respectively, 6.9-8.7, 595-1248 µS/cm, 6.4-8.0 mg/l for pH, electric conductivity and dissolved oxygen respectively. A total of 74 taxa were recorded for diatoms, where the pinnate diatom was the predominant and recorded 64 taxa while 10 taxa for centric diatoms. The total number of diatoms was 1197.55*104 cell /l. The total number values were ranged as follows:( 28.3-48.6) *104 cell /l in the first site ,( 33.6-51.5) *104 cell /l in the second site,( 39.8-67.2) *104 cell /l in the third site and ( 22.3-38.0) *104 cell /l in the fourth site. Two species Asterionellaformosa Hassall and Diploneispuella Schumann were noticed in site 2 only, while C. prostateBerkeleyfound in all studied sites expect in site 1. StephaenodicushantzschiiGrunow and Didymosphenia geminate (lyngb.) Schmidtwere recorded in sites 1 and 3, Anomoeoneissp was recorded in sites 1 and 4 only. The Mastogloiasp was noticed only in sites 2 and 4.

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