scholarly journals The Strategy of Phytoplankton on Critical Conditions in Coastal Waters

2020 ◽  
Vol 8 (1) ◽  
pp. 11
Author(s):  
Rahmadi Tambaru ◽  
Muh. Farid Samawi ◽  
Khairul Amri
Keyword(s):  
Incubation Time ◽  
Coastal Waters ◽  
Critical Time ◽  
Sampling Time ◽  
Critical Conditions ◽  
Environmental Condition ◽  
Phytoplankton Abundance ◽  
Group I ◽  
Components Analysis ◽  
Sunlight Intensity

The productivity of phytoplankton found best in coastal waters is on a critical aquatic environmental condition for the life of phytoplankton (incubation time : 10.00-14.00). At that incubation time, the sun reached the apex of illumination (12.00). Theoretically, the best productivity is unlikely to happen because the activity of phytoplankton is not perfect. To answer that doubt, the research deals with the strategy of life phytoplankton on critical conditions in coastal waters. To achieve the desired results, multivariate analysis is used Correspondent analysis (CA) and Principal Components Analysis (PCA). The results showed that based on the analysis of Factorial Koresponde (CA), there were two grouping of phytoplankton  abundance. Group I showed that the grouping of phytoplankton  abundance of occurred at A depth of 10 m at the sampling  time A (10.00 : normal conditions). Group II occurs at a depth of 5 and 15 m at sampling time B (14.00: critical condition). Furthermore, the shift in grouping phytoplankton occurs at the sampling  time A at a depth of 10 m into the sampling time B in 5 m depth, not at at a depth of 0 m. This is due to the very strong sunlight intensity that can lead to death in the genera of phytoplankton that exist. It turns out that the strategy and the dynamics of phytoplankton abundance at critical time is not doing the grouping at the surface depth (0 m), but at a deeper depth (5 m) in order to keep the activity well done.

scholarly journals Length-length Relationship, Weight-Length Relationship, Sex Ratio and factor of Condition of Sardinella maderensis (Lowe, 1838) in South-Eastern Coastal waters of Benin

2020 ◽  
Vol 3 (3) ◽  
Keyword(s):  
Coastal Waters ◽  
Condition Factor ◽  
Stock Assessment ◽  
Central Area ◽  
Environmental Condition ◽  
Small Pelagic Fish ◽  
Relative Condition Factor ◽  
Length Relationship ◽  
Significant Difference ◽  
Shared Character

Face to decreasing of high-value commercial fishes’ stocks particularly of small pelagic fish in the central part of FAO fishery area 34, the present study has been carried out. From November 2016 to June 2018, monthly 1041 specimens of Sardinella maderensis were collected from southeastern coastal water of Benin randomly. Standard and Total Length, and weight as well as, the sex data were collected.t-test, z-test and ANOVA one tail test were performed to determine whether there was a significant difference between data. With a ratio of 1:1.5 statistically different from 1:1 (p<0.001), female dominate S. maderensis population in Benin. Negative allometry both for the female (2.92) the male (2.88) and combined sexes (2.90) highly different from the consensus, “b=3” (p<0.001) is remarked. The relative condition factor computed from the allometry shows an average environmental condition for S. maderensis growth. Regarding the shared character of S. maderensis stock in CECAF’s central area, these results are important for the next stock assessment..

scholarly journals Comparison of short and long co-incubation time of gametes for in vitro fertilization

2019 ◽  
Vol 8 (11) ◽  
pp. 4366
Author(s):  
Pallop Pongsuthirak
Keyword(s):  
In Vitro Fertilization ◽  
Incubation Time ◽  
Pregnancy Outcomes ◽  
Fertilization Failure ◽  
Vitro Fertilization ◽  
Group I ◽  
Significant Difference ◽  
Total Fertilization Failure ◽  
Rescue Icsi

Background: The short and long co-incubation time of gametes for in vitro fertilization are still debatable issues. This study aims to investigate the effects of short and long co-incubation time of gametes on fertilization, polyspermy, embryonic developmental potential, and clinical outcomes.Methods: Sixty-five patients undergoing IVF treatment were invited to participate in the study between May 2017 and March 2019. Ovarian hyperstimulation was prescribed and oocytes were obtained by trans-vaginal aspiration under ultrasound guidance. Sibling oocytes were randomly allocated to short co-incubation for 4 hours (Group I) in 352 oocytes and long co-incubation for 16-18 hours in 363 oocytes (Group II). Rescue ICSI was carried out if total fertilization failure was documented. Fertilization, embryonic development, and pregnancy outcomes were determined.Results: No significant differences between short and long co-incubation were found in fertilization, polyspermy, cleavage, blastocyst, implantation, clinical pregnancy, and live birth rates.Conclusions: The present study showed that short co-incubation of gametes had no significant difference in fertilization, polyspermy, embryo development, and pregnancy outcomes when compared to long co-incubation. The short co-incubation with early cumulus cell removal and rescue ICSI may have the potential to help a couple who had total fertilization failure.

scholarly journals The Analysis of Phytoplankton Abundance Using Weibull Distribution (A Case Study in the Coastal Area of East Yapen in the Regency of Yapen Islands, Papua)

2018 ◽  
Vol 7 (3) ◽  
pp. 251
Author(s):  
Ervina Indrayani ◽  
Lisiard Dimara ◽  
Kalvin Paiki ◽  
Felix Reba
Keyword(s):  
Coastal Waters ◽  
Likelihood Estimation ◽  
Cumulative Probability ◽  
Marine Biota ◽  
Phytoplankton Abundance ◽  
Chi Square ◽  
Phytoplankton Distribution ◽  
Distribution Parameters ◽  
Primary Producer ◽  
Special Studies

The coastal waters of East Yapen is one of the spawning sites and areas of care for marine biota in Papua. Because of its very open location, it is widely used by human activities such as fishing, residential, industrial and cruise lines. This indirectly affects the balance of coastal waters condition of East Yapen that impact on the existence of marine biota, especially phytoplankton. Phytoplanktons have a very important role because phytoplankton is the primary producer in the food chain as a link to higher tropical levels. Therefore, special studies are needed such as looking at the distribution of phytoplankton abundance at each site. The data analysis uses the American Public Health Association (APHA), Geo-statistical data, and Chi Square. Then, the distribution parameters are estimated using the Maximum Likelihood Estimation (MLE) method.The obtained parameters are used to describe the cumulative probability and survival of phytoplankton distribution. Samples are taken from fifteen sampling points. The form parameter of the phytoplankton abundance data is 3.9844 and the scale parameter is 79.929. So phytoplankton is the most widely spread in the 15th location, followed by the 6th location. While phytoplankton is at least in the 8th location.The results showthat the highest phytoplankton abundance composition is Bacillariophyceae (50%) and the lowest is Phyrrophyceae (9%) and Cyanophceae. The research is expected to provide an overview of the fertility rate of East Yapen Coastal Waters in particular and Yapen Islands regency in general.

scholarly journals STRUKTUR KOMUNITAS SUMBERDAYA IKAN PADANG LAMUN DI TELUK EKASLOMBOK TIMUR

2019 ◽  
Vol 15 (1) ◽  
Author(s):  
Karnan Karnan ◽  
Lalu Japa ◽  
Ahmad Raksun
Keyword(s):  
Coastal Waters ◽  
Intertidal Zone ◽  
Fish Habitat ◽  
Research Area ◽  
Environmental Condition ◽  
Strong Indication ◽  
Beach Seine ◽  
Low Diversity ◽  
Key Words Fish ◽  
Swept Area

AbstractResearch on seagrass fishes resources condition was conducted in the intertidal zone of Ekas Bay, East Lombok. Sampling of fishes was conducted using the swept area method with beach seine. The result of this research in three station showed that the degree of fishes diversity was low. There was a strong indication that the fishes species in the research area were dominated by certain fish species. In general, the firtility of Ekas Bay coastal water was semilar with the other coastal waters, however the environmental condition mainly the low of persentage of seagrass covering in the research location was the main couse of the low diversity of seagrass fish of the area. High exploitation followed by destruction methods of exploitation can be the main causes of fish degradation habitat, mainly in the seagrass of Ekas Bay, East Lombok. Key words: fish habitat, Lombok, marine,seagrass fishs AbstrakPenelitian kondisi sumberdaya ikan padang lamun telah dilakukan di wilayah intertidal Teluk Ekas, Lombok Timur. Pengambilan sampel ikan menggunakan metode swept area dengan pukat pantai (beach seine) di tiga stasiun pengamatan menunjukkan bahwa tingkat keanekaragaman ikan di lokasi penelitian rendah. Ada indikasi yang sangat kuat bahwa dominansi suatu jenis ikan di setiap stasiun pengamatan. Secara umum, kesuburan perairan Teluk Ekas relatif sama dengan perairan lainnya, namun kondisi lingkungan terutama persentasi penutupan padang lamun yang rendah menjadi penyebab utama rendahnya keanekaragaman ikan padang lamun di lokasi penelitian. Tingkat eksploitasi yang tinggi disertai dengan cara eksploitasi yang tidak mempertimbangkan kesinambungan pemanfaatan sumberdaya menjadi penyebab rusaknya habitat ikan, khususnya padang lamun di Teluk Ekas, Lombok Timur. Kata kunci: ikan padang lamun, habitat ikan, laut, Lombok.

scholarly journals Abundance of Phytoplankton In The Coastal Waters of South Sumatera

2017 ◽  
Vol 22 (1) ◽  
pp. 31
Author(s):  
Riris Aryawati ◽  
Dietriech G. Bengen ◽  
Tri Prartono ◽  
Hilda Zulkifli
Keyword(s):  
Water Quality ◽  
Primary Production ◽  
Food Chain ◽  
Coastal Waters ◽  
Diversity Index ◽  
Mesh Size ◽  
Phytoplankton Species ◽  
Phytoplankton Abundance ◽  
Dominance Index

Phytoplankton in the ocean has an important role in forming the base of food chain,  responsible in primary production. Its abundance and number of phytoplankton species will indirectly affect the level of water’s fertility. This study aimed to determine the presence of phytoplankton as bio-indicators of water quality in terms of abundance, diversity index, uniformity index, and saprobic coefficient in coastal waters of South Sumatera. The study was conducted on May 2013 - February 2014, at ten stations during high and low tides. Phytoplankton samples were taken vertically using plankton nets,  cone-shaped with a diameter of 30 cm, length 100 cm and mesh size 30 μm. The study found 41 genera of phytoplankton, consisted of family Bacillariophyceae (26 genera), Dinophyceae (7 genera) Cyanophyceae (7 genera) and Chlorophyceae (1 genus). The highest number of genera was recorded while low tides in November (24 genera), and the lowest was on May while high tides (16 genera). The highest abundance of phytoplankton was recorded in August during high tides (2,68 x 107 cell.m-3), and the lowest was in May during high tides (6,59 x 105cell.m-3). The diversity index (H'),  the uniformity index (E), and the dominance index (D) ranged between 0,64–3; 0,15–0,71 and 0,15–0,83 respectively.  Keywords: phytoplankton, abundance, diversity index, South Sumatera coast.

Determining the No-Recrystallization Conditions for Industrial Hot Strip Rolling of Steels Using Laboratory Simulations

2012 ◽  
Vol 706-709 ◽  
pp. 1409-1414 ◽  
Author(s):  
Gwenola Herman ◽  
Evgueni I. Poliak
Keyword(s):  
Hot Rolling ◽  
Incubation Time ◽  
Rolling Process ◽  
Critical Conditions ◽  
Recrystallization Temperature ◽  
Static Case ◽  
Hot Strip Rolling ◽  
Strip Rolling ◽  
Hot Strip ◽  
Cold Rolling And Annealing

Avoiding recrystallization of austenite in hot strip rolling of steels is highly important for enhancing mechanical properties of hot rolled products, as well as for the products undergoing cold rolling and annealing or coating. Recrystallization can only be avoided if its incubation time is longer that the time intervals characteristic for a particular hot rolling process. The present work focuses on computation of incubation time tinc for static recrystallization using laboratory hot deformation data and on extrapolation the results to industrial conditions. The computations are done based on application of critical conditions for initiation of dynamic recrystallization to the static case. No-recrystallization temperature in hot strip rolling is determined by setting tinc equal to interpass time. Simulations allow for prediction of the onset of austenite static or metadynamic recrystallization after individual rolling passes during industrial hot rolling and evaluation of the effects of strip thickness, rolling speeds, etc.

Growth aspect of squid (Loligo chinensis) from the Banyuasin Coastal Waters, South Sumatra, Indonesia

2020 ◽  
Vol 27 ◽  
pp. 1-10
Author(s):  
Fauziyah . ◽  
Anna I.S. Purwiyanto ◽  
Fitri Agustriani ◽  
Wike A.E. Putri
Keyword(s):  
Coastal Waters ◽  
Growth Pattern ◽  
Condition Factor ◽  
Critical Value ◽  
Small Scale ◽  
Environmental Condition ◽  
Small Scale Fisheries ◽  
Relative Condition Factor ◽  
The Mean ◽  
First Maturity

Squid (Loligo chinensis) played an important role in small scale fisheries in Banyuasin Coastal Waters, however, the information and publications were limited. This study aimed to estimate the length at first capture (LC50%), the length at first maturity (Lm), growth pattern and condition factor of L. chinensis from Banyuasin Coastal Waters of South Sumatra. The squids were observed for samples in April 2018 and March 2019 using a stationary lift net. During the observation, the squid measurement was conducted on 1179 individuals. The mantle length ranged was 40-210 mm and their body weight ranged was 2-42 gr. The value of LC50%, Lm and ½L∞ were obtained at 103 mm, 147 mm, and 110.5 mm respectively. The analysis results of the length-weight relationship (W = 0.0145L1.4618, R2 = 0.9265 and P < 0.05) showed that their growth pattern was negative allometric (b < 3).  The mean relative condition factor (Kn = 1.01) above the critical value limits (K=0.56) confirmed that the environmental condition of Banyuasin Coastal Waters suitable for the L. chinensis growth. However, should be careful with their length size of the squid catch were not feasible in the capture.

scholarly journals NUTRIENT CONCENTRATION AND PH IN THE CISADANE ESTUARINE AND COASTAL WATERS

2018 ◽  
Vol 32 (2) ◽  
pp. 63-74
Author(s):  
Muswerry Muchtar
Keyword(s):  
Surface Water ◽  
Coastal Waters ◽  
Inorganic Phosphate ◽  
Mangrove Forest ◽  
Nutrient Concentration ◽  
Nutrient Concentrations ◽  
Environmental Condition ◽  
Open Sea ◽  
Phosphate Nitrate

The study on the fluctuation of dissolved nutrient concentrations and acidity (pH) in the Cisadane Estuary was carried out in May 2004 October 2004 and July 2005. Inorganic phosphate, nitrate and silicate of the surface water were analyzed, using Spectrophotometer and pH was measured with a pH meter. Generally the nutrient concentrations in the estuary were higher compared to those in the coastal and offshore areas. The concentrations were gradually becoming lower and lower toward the open sea. Their fluctuation depended not only on the environmental condition but also on the water volurrie from the land and the mangrove forest in that area.

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