Elevated sea-water temperature and solar UV-B flux associated with two successive coral mass bleaching events in Tahiti

1995 ◽  
Vol 46 (8) ◽  
pp. 1153 ◽  
Author(s):  
JH Drollet ◽  
M Faucon ◽  
PMV Martin
Keyword(s):  
Water Temperature ◽  
Coral Bleaching ◽  
Sea Water ◽  
Bleaching Event ◽  
Chemical Parameters ◽  
Physico Chemical ◽  
Long Line ◽  
Solar Uv ◽  
Line Transects ◽  
A Minor

After a minor coral bleaching event in 1993, a more dramatic episode occurred in Tahiti from March to July 1994. Coral bleaching was recorded along four continuous 25-m-long line transects. Physico-chemical parameters of the sea water (temperature, salinity, dissolved oxygen and pH) were noted once a week, and solar UV-B flux was recorded daily before and during the bleaching episode. Results emphasized the importance of the taxonomic position of coral in susceptibility to bleaching. The evolution of bleaching through time was related to mean daily solar UV-B flux and sea-water temperature. Moreover, comparison of the 1993 and 1994 data suggested temperature and/or UV-B thresholds that may elicit minor or severe bleaching events.

A survey of environmental physico-chemical parameters during a minor coral mass bleaching event in Tahiti in 1993

1994 ◽  
Vol 45 (7) ◽  
pp. 1149 ◽  
Author(s):  
JH Drollet ◽  
M Faucon ◽  
S Maritorena ◽  
PMV Martin
Keyword(s):  
Solar Irradiance ◽  
Sea Water ◽  
Seawater Temperature ◽  
Total Solar Irradiance ◽  
Chemical Parameters ◽  
Physico Chemical ◽  
Hermatypic Corals ◽  
Solar Uv ◽  
Line Transects ◽  
A Minor

Hermatypic corals along two continuous 25-m-long line transects on the northern and eastern coasts of the island of Tahiti (Arue, buter reef slope, and Hitia'a, fringing reef, respectively) were monitored during a minor episode of coral bleaching in April and May 1993. From early February to the end of May, the physico-chemical parameters of the sea water (temperature, salinity, dissolved oxygen, pH and total solar irradiance) were noted once a week, and solar UV-B radiation was recorded from 1100 to 1400 hours every day. The results are consistent with a synergistic interaction between temperature and UV-B radiation, possibly associated with total solar irradiance. The interval of four weeks between peaks in solar UV-B radiation and seawater temperature may explain why the 1993 bleaching in Tahiti was minor. Different patterns of bleaching occurred in different species, and all corals recovered within four to six weeks. Hermatypic corals appear to have multiform reactions in response to environmental stresses.

scholarly journals Study on physico-chemical features of water in Tarahara Fish Farm, Sunsari, Nepal

2017 ◽  
Vol 7 (1) ◽  
pp. 47-57
Author(s):  
Ganesh Bahadur Thapa ◽  
Joydeb Pal
Keyword(s):  
Water Quality ◽  
Water Temperature ◽  
Air Temperature ◽  
Physicochemical Parameters ◽  
Quality Parameters ◽  
Fish Farm ◽  
Fish Growth ◽  
Chemical Parameters ◽  
Physico Chemical ◽  
Peripheral Areas

Tarahara Fish Farm includes 37 large ponds as a fish super zone. Physicochemical parameters viz., air and water temperature, pH, DO, BOD, CO2, Cl-, TA and TH of these ponds were studied for two years (Nov. 2008 to Oct. 2010). The air temperature had positive and significant correlation with water temperature (r=0.893, P<0.01) but inverse and significant correlation with DO (r = - 0.669 P<0.05) and TH (r = - 0.673, P<0.05). Both air and water temperature showed a decreasing trend during the winter months of November to January and again September to October in both years. Similarly, positive and significant correlation showed by pH with DO (r =0.660, P<0.05) and BOD (r =0.846, P<0.05); by free CO2 with DO (r=0.854, P<0.01), chloride (r=0.648, P<0.05) and TA (r=0.616, P<0.05); by DO with TA (r =0.715, P<0.01) and chloride (r =0.625, P<0.05) and by TH with TA (r= 0.592, P<0.05) but inverse and significant correlation showed by pH with water temperature (r =-0.671, P<0.05); by free CO2 with BOD (r=-0.627, P<0.05) and by DO with BOD (r = -0.810, P <0.01). The water quality parameters were within suitable range for the fish growth and breeding with small fluctuations in different months during the first and second years. Physico-chemical parameters significantly (P<0.01; 0.05) differed between different months. However, no mass mortality of fish was recorded from this site. So, the area selected as fish super zone is fruitful to meet the expected production level of fishes and fish seeds in peripheral areas.

scholarly journals Investigation of parasite and diseases at cage culture Nile tilapia (Oreochromis niloticus) in Southern region of Bangladesh

2020 ◽  
Vol 6 (3) ◽  
pp. 431-437
Author(s):  
Mohammad Ashaf Ud Doulah ◽  
SM Majharul Islam ◽  
Mohammad Shadiqur Rahman ◽  
Md Shariful Islam ◽  
Mohammad Harun Or Rashid ◽  
...  
Keyword(s):  
Mortality Rate ◽  
Dissolved Oxygen ◽  
Water Temperature ◽  
Oreochromis Niloticus ◽  
Nile Tilapia ◽  
Cage Culture ◽  
Chemical Parameters ◽  
Physico Chemical ◽  
Nile Tilapia Oreochromis Niloticus ◽  
Eleven Species

The study was carried out to identify the parasite and causative diseases on cage reared tilapia at Bakerganj upazila, Barisal district. The infected tilapia fishes were collected from the cages and brought to the laboratory to find out signs, symptoms and infection area on the fish body. Physico-chemical parameters of water, such as water temperature, pH, dissolved oxygen, nitrate, phosphate and ammonia were monitored fortnightly. The values of water temperature (°C), pH, dissolved oxygen (mg/l), nitrate (mg/l), phosphate (mg/l) and ammonia (mg/l) were 32.4±2.1, 6.2±0.3, 7.52±0.4, 0.028±.008, 11.30±2.26 and 0.09±0.02, respectively but the concentration of nitrate was so higher during the study time. Eleven species of parasites namely, Chilodonella sp, Trichodiniasp., Gyrodactylussp.,Cichlidogyrus sp., Capillariasp, Orientocreadium sp, Eustrongylidae sp, Allocreadium sp, Euclinostomum sp, Tylodelphys sp. and Metagonimus spwere were identified. Parasites were found on all the examined parts of the fish body but gill showed the most infested area of the host. Highest mortality rate was occurred in the month of October and lowest mortality rate was in July. In this circumstance, proper management system and handling are best ways to prevent diseases and reduce the mortality rate of tilapia on cage farming in the southern area. Res. Agric., Livest. Fish.6(3): 431-437, December 2019

Total Biomass and Carbon Estimates in Mangrove Species of Bhitarkanika Wildlife Sanctuary (BWLS), Odisha

2018 ◽  
Vol 4 (02) ◽  
pp. 27-34
Author(s):  
Kakoli Banerjee ◽  
Gobinda Bal ◽  
Rakesh Paul
Keyword(s):  
Environmental Changes ◽  
Sea Water ◽  
Water Discharge ◽  
Total Carbon ◽  
Total Biomass ◽  
Chemical Parameters ◽  
Wildlife Sanctuary ◽  
Mangrove Species ◽  
Physico Chemical ◽  
Fresh Water Discharge

We estimated total biomass and total carbon in 18 selected woody mangrove species based on the IVI values along with physico-chemical parameters of sea water and soil. AGB and BGB values were calculated as per the standard protocol in BWLS in five sampling stations namely Dangmal, Bhitarkanika, Habalikhati, Ekakula and Gupti. The highest values of IVI were noted for E. agallocha followed by A. officinalis, A. marina, H. fomes and C. decandra. Total biomass of species range was found to be varying between 0.69 tha-1 in X. molluccensis and 2122.17 tha-1 in A. officinalis. Total site-wise biomass ranged between 0.22 tha-1 in B. cylindrica at Gupti and 1419.26 tha-1 in A. officinalis at Bhitarkanika. Total carbon was considered to be 50% of total dry biomass which varied from 188.45±21.87 tha-1 at Ekakula to 941.31±201.17 tha-1 at Bhitarkanika, respectively. The higher biomass and carbon in A. officinalis proves it to be highly adaptive to the environmental changes in the present geographical locale. The maximum biomass and carbon of all the mangrove species in station Bhitarkanika is due to the fact that this station receives the fresh water discharge of Baitarani river thereby the adequate lower salinity is maintained. The present study reveals that mangroves of Bhitarkanika Wildlife Sanctuary can store substantial amount of atmospheric carbon and therefore needs to be conserved and sustainably managed.

scholarly journals Physico-chemical properties of water of Ramshagar dighi, the largest man made historical reservoir in northern Bangladesh

2018 ◽  
Vol 23 ◽  
pp. 29-37
Author(s):  
Ashaduzzaman ◽  
MJ Hossain ◽  
S Akther
Keyword(s):  
Carbon Dioxide ◽  
Dissolved Oxygen ◽  
Water Temperature ◽  
Air Temperature ◽  
Water Depth ◽  
Chemical Properties ◽  
Current Status ◽  
Chemical Parameters ◽  
Monthly Average ◽  
Physico Chemical

Ramshagar dighi is a larger historical man made reservoir (Dighi, Bengali meaning) situated at Tajpur village in Dinajpur, Bangladesh. This study was aimed to estimate current status of physico-chemical variables of water of Ramshagar dighi at Dinajpur District, Bangladesh. Monthly average changes in physico-chemical parameters such as water temperature, total dissolved oxygen, air temperature, humidity, rainfall, water depth and pH of water were analyzed for the period of 11 months from May 2011 to March 2012. The average air temperature (°C) at the study area of Ramshagar dighi at Dinajpur District was determined as 24.97 ± 4.92. Our present study showed that physico-chemical properties of water in Ramshagar dighi were monthly average of water temperature (°C) as 24.68 ± 4.77, air temperature (°C) 24.97 ± 4.92, humidity as 82.075 ± 4.14, rainfall as 1534.5 mm, water depth as 9.10 m ± 1.286, pH as7.67± 0.48 and carbon dioxide as 0.85 ± 0.92 as well as dissolved oxygen as 4.65 ± 0.62 respectively during the period of May 2011 to March 2012. Therefore, present study was conducted to assess physico-chemical properties of water of Ramshagar dighi, Dinajpur, Bangladesh.J. bio-sci. 23: 29-37, 2015

scholarly journals Monthly Variation of Physico-Chemical Parameters of Haleji lake, Sindh, Pakistan

2019 ◽  
Vol 10 (1) ◽  
pp. 36-41
Author(s):  
Shahina Rao ◽  
Muhammad Arshad Azmi
Keyword(s):  
Dissolved Oxygen ◽  
Water Temperature ◽  
Air Temperature ◽  
Physical Factors ◽  
Monthly Variation ◽  
Chemical Parameters ◽  
Physico Chemical ◽  
Light Green

Present work is based on the physico-chemical parameters of Haleji lake. Physical factors and chemistry oflake water were analyzed with regular intervals. The color of water showed variation from light green to yellowishgreen, air temperature ranged between 20 °C to 35 °C, water temperature between 17 °C to 33 °C , pH 5.5 to 7.5,dissolved oxygen 2.04 mg/L to 6.44 mg/L, salinity 0.32 mg/L to 1.1 mg/L, alkalinity from 30 mg/L to 100 mg/L,acidity 10 to 96 mg/L, sulphate 4.5 mg/L to 305 mg/L, phosphate from 1 mg/L to 190 mg/L, and nitrates 9 mg/L to 270mg/L during 2006, 2007 and 2008 respectively.

scholarly journals Early trajectories of benthic coral reef communities following the 2015/16 coral bleaching event at remote Aldabra Atoll, Seychelles

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Anna Koester ◽  
Valentina Migani ◽  
Nancy Bunbury ◽  
Amanda Ford ◽  
Cheryl Sanchez ◽  
...  
Keyword(s):  
Coral Reef ◽  
Water Temperature ◽  
Coral Bleaching ◽  
Coral Cover ◽  
Bleaching Event ◽  
Hard Coral ◽  
Reef Communities ◽  
Remote Sites ◽  
Hard Coral Cover ◽  
Coral Reef Communities

Abstract Documenting post-bleaching trajectories of coral reef communities is crucial to understand their resilience to climate change. We investigated reef community changes following the 2015/16 bleaching event at Aldabra Atoll, where direct human impact is minimal. We combined benthic data collected pre- (2014) and post-bleaching (2016–2019) at 12 sites across three locations (lagoon, 2 m depth; seaward west and east, 5 and 15 m depth) with water temperature measurements. While seaward reefs experienced relative hard coral reductions of 51–62%, lagoonal coral loss was lower (− 34%), probably due to three-fold higher daily water temperature variability there. Between 2016 and 2019, hard coral cover did not change on deep reefs which remained dominated by turf algae and Halimeda, but absolute cover on shallow reefs increased annually by 1.3% (east), 2.3% (west) and 3.0% (lagoon), reaching, respectively, 54%, 68% and 93% of the pre-bleaching cover in 2019. Full recovery at the shallow seaward locations may take at least five more years, but remains uncertain for the deeper reefs. The expected increase in frequency and severity of coral bleaching events is likely to make even rapid recovery as observed in Aldabra’s lagoon too slow to prevent long-term reef degradation, even at remote sites.

scholarly journals Monthly Variation of Physico-Chemical Parameters of Haleji lake, Sindh, Pakistan

2019 ◽  
Vol 10 (1) ◽  
pp. 36-41
Author(s):  
Shahina Rao ◽  
Muhammad Arshad Azmi
Keyword(s):  
Dissolved Oxygen ◽  
Water Temperature ◽  
Air Temperature ◽  
Physical Factors ◽  
Monthly Variation ◽  
Chemical Parameters ◽  
Physico Chemical ◽  
Light Green

Present work is based on the physico-chemical parameters of Haleji lake. Physical factors and chemistry oflake water were analyzed with regular intervals. The color of water showed variation from light green to yellowishgreen, air temperature ranged between 20 °C to 35 °C, water temperature between 17 °C to 33 °C , pH 5.5 to 7.5,dissolved oxygen 2.04 mg/L to 6.44 mg/L, salinity 0.32 mg/L to 1.1 mg/L, alkalinity from 30 mg/L to 100 mg/L,acidity 10 to 96 mg/L, sulphate 4.5 mg/L to 305 mg/L, phosphate from 1 mg/L to 190 mg/L, and nitrates 9 mg/L to 270mg/L during 2006, 2007 and 2008 respectively.

scholarly journals Comparative Assessment of Physico-Chemical Parameters of Lotic and Lentic Zone of River Betwa in Jhansi (U.P.), India

2020 ◽  
Vol 26 (2) ◽  
Author(s):  
Umesh Kumar Mishra ◽  
Vijay Kumar Yadav
Keyword(s):  
Water Temperature ◽  
Electric Conductivity ◽  
Comparative Assessment ◽  
Total Alkalinity ◽  
Total Hardness ◽  
Chemical Parameters ◽  
Human Race ◽  
Water Parameters ◽  
Physico Chemical ◽  
Two Samples

Water is the most precious natural gift given by God to human race. Its purity is also important for everyone. For the present study two sampling stations, Baratha village and Parichha dam head were selected for comparative assessment of physico-chemical parameters of lotic and lentic zones on Betwa river. Both these sampling stations are located at Jhansi (UP) India. Samples were collected regularly for one complete year from July 2018 to June 2019. Eighteen water parameters and four hundred thirty two samples were analysed. The overall mean ranges of these parameters at Baratha village and Parichha dam head were notified as electric conductivity (518.66±43.47) and (528.75±59.65), pH (8.09±0.36) and (8.14±0.26), water temperature (24.37±4.14) and (23.78±4.12), transparency (54.91±4.97) and (41.61±3.83), turbidity (30±12.38) and (35.25±16.38), TDS (265.33±16.74) and (267.66±25.42), TSS (66.5±12.52) and 69.83±14.45), TS (331.83±28.76) and (337.5±39.04), DO (6.76±0.68) and (6.72±0.86), total alkalinity (141.58±22.74) and (142.25±29.37), total hardness (150.08±22.70) and (153.66±20.55), Ca (29.04±2.32) and (29.84±5.38), Mg (13.51±2.01) and (14.32±2.20), chloride (24.77±3.29) and (26.85±3.99), BOD (4.08±0.71) and (4.15±1.16), COD (11.64±1.02) and (12.82±1.20), NO3 (1.64±0.37) and (1.93±0.59), PO4 (0.46±0.21) and (1.33±0.29). All these findings concluded that the lentic zone (Parichha) is more polluted than the lotic zone (Baratha). However all the observed values are in the range of permissible limits, so both zones can be used for irrigation and fisheries sector.

scholarly journals Kesesuaian areal budidaya rumput laut berdasarkan kapasitas perairan Desa Arakan Kabupeten Minahasa Selatan

2013 ◽  
Vol 1 (1) ◽  
Author(s):  
Handy Burase ◽  
Robert Rompas ◽  
Edwin L.A. Ngangi
Keyword(s):  
Carrying Capacity ◽  
Sea Water ◽  
Chemical Parameters ◽  
Muddy Sand ◽  
Potential Production ◽  
Culture Area ◽  
Coral Sand ◽  
Long Line ◽  
Physical And Chemical ◽  
Planting Season

The purpose of this research was to provide data on waters physical and chemical parameters, proper areal map, carrying capacity, and potential production of seaweed. Research method used was spacial approach through direct measurement in the field and through laboratory analysis. Ten observation stations were established purposively at Desa Arakan waters. Samples were collected four times at two weeks interval. It was found that water temperature was 31–31,25 ºC, flow rate 5,97–11,09 cm/det., dissolved oxygen 5,34–6,45 mg/l, pH 7,7–8,1, salinity 32,5-33 ppt, nitrate 5,02–5,25 mg/l, phosphate 0,01–0,14 mg/l, water depth 1,3–16,5 m, velocity 1,3–4,5 m, tide 0–283 cm with Mean Sea Level 75,6 cm. bottom substrate consisted of coral sand and muddy sand. Proper culture area based on SIG analysis was 134.64 ha in which very proper areal was 68.40 ha, proper 66.23%. while proper areal was 66.23 ha. Based on carrying capacity analysis, proper sustainable site was 126.57 ha. This area could support 1.054 long line measuring 20x60 cm each. Seaweed potential was 3363,7 ton per ha or 4.4 ton/ha/year or 4.4 ton/ha/planting season. Keywords: marine seaweed, water quality, SIG, sea water, SIG, carrying capacity, production

Sign in / Sign up

Export Citation Format

Share Document