scholarly journals Effects of gamete dilution, age and contact time on fertilization success in the tropical sea urchin, Echinometra mathaei

2001 ◽  
Vol 2001 (3) ◽  
pp. 1-12 ◽  
Author(s):  
M. Aminur Rahman ◽  
S. Mustafizur Rahman ◽  
T. Uehara
2003 ◽  
Vol 20 (5) ◽  
pp. 617-626 ◽  
Author(s):  
Tetsuya Kominami ◽  
Hiromi Takata

Water ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 775
Author(s):  
Mary McGann

The benthic foraminifers Bulimina denudata and Eggerelloides advenus are commonly abundant in offshore regions in the Pacific Ocean, especially in waste-discharge sites. The relationship between their abundance and standard macrofaunal sediment toxicity tests (amphipod survival and sea urchin fertilization) as well as sediment chemistry analyte measurements were determined for sediments collected in 1997 in Santa Monica Bay, California, USA, an area impacted by historical sewage input from the Hyperion Outfall primarily since the late 1950s. Very few surface samples proved to be contaminated based on either toxicity or chemistry tests and the abundance of B. denudata did not correlate with any of these. The abundance of E. advenus also did not correlate with toxicity, but positively correlated with total solids and negatively correlated with arsenic, beryllium, chromium, lead, mercury, nickel, zinc, iron, and TOC. In contrast, several downcore samples proved to be contaminated as indicated by both toxicity and chemistry data. The abundance of B.denudata positively correlated with amphipod survival and negatively correlated with arsenic, cadmium, unionized ammonia, and TOC; E. advenus negatively correlated with sea urchin fertilization success as well as beryllium, cadmium, and total PCBs. As B. denudata and E. advenus are tolerant of polluted sediments and their relative abundances appear to track those of macrofaunal toxicity tests, their use as cost- and time-effective marine sediment toxicity tests may have validity and should be further investigated.


2014 ◽  
Vol 19 (2) ◽  
pp. 75 ◽  
Author(s):  
Cristiana Manullang ◽  
Makoto Tsuchiya ◽  
Ambariyanto Ambariyanto ◽  
Diah Permata

Bioerosi adalah aktivitas berbagai organisme yang menyebabkan terjadinya erosi dan kerusakan misalnya pada kalsium karbonat karang. Aktivitas ini merupakan faktor utama yang mempengaruhi morfologi terumbu karang. Bioerosi dipengaruhi oleh tiga variabel yakni jenis spesies, ukuran dan kelimpahan spesies tersebut. Tujuh puluh lima persen dari bioerosi disebabkan oleh landak laut. Perbedaan pada ukuran dan jenis landak laut memberikan dampak signifikan terhadap daerah yang terjadi bioerosi. Penelitian ini bertujuan untuk menguji pengaruh ukuran dan jenis landak laut E. mathaei (tipe A dan B) pada komposisi CaCO3 dalam isi usus dan tinja organisme tersebut sebagai agen bioersi. Landak laut yang digunakan diperoleh dari ekosistem karang di pantai Minatogawa, Okinawa-Jepang. Masing-masing tipe landak laut dibedakan berdasarkan ukuran ≥30 mm dan <30mm. Penelitian dilakukan dengan tiga ulangan. Pemeliharaan ini dilakukan di laboratorium dengan analisis komposisi CaCO3 pada tinja dan konten usus. Hasil penelitian membuktikan bahwa komposisi CaCO3 disebabkan karena aktivitas bioerosi harian dari E. mathaei. Landak laut dengan ukuran diameter ≥30 mm terbukti lebih aktif dibandingkan dengan diameter <30mm. Disamping itu landak laut tipe B lebih aktif dibandingkan tipe A dengan ukuran yang sama. Persentase CaCO3 dalam usus selama pemeliharaan di laboratorium adalah 73% dan sisa 27% berupa bahan organik dan anorganik. Bierosion harian E. mathaei tipe A ≥ 30 mm 166,70 mg.hari-1, tipe A <30 mm 77.78 mg.hari-1, tipe B ≥ 30 mm 126,30 mg.hari-1, tipe B <30 mm 116,17 mg.hari-1. Tingkat bioerosion harian E. mathaei dipengaruhi oleh jenis, spesies, kecepatan menggiling, dan ukuran landak laut. Kata kunci: ukuran; Echinometra mathaei; bioerosi; karang Bioerosion is an activity of various organisms such as erosion and destruction of coral calcium carbonate and become a major factor influencing coral reefs morphology. Bioerosion is influenced by three variables: type of species, size of species and abundance. Seventyfive percent of bioerosion caused by sea urchin. Differences on size and type of sea urchin gave a significant impact to the bioerosion area. This study aimed to examine the influence of the size and the type of sea urchin E. mathaei (type A and type B) on the composition of CaCO3 in the gut content and feces as bioersion agent on the reef flat in Minatogawa Coast, Okinawa-Japan. The organisms used were E. mathaei type A and type B with each type distinguished by size ≥ 30 mm and < 30 mm with three replications. The maintenance was carried out at laboratory for 3 days by observing analysis of the composition of CaCO3 on feces and gut content. It indicates that the composition of CaCO3 as daily bioerosion was caused by E. mathaei. The results showed E. mathaei with diameter ≥ 30 mm was more active than those with diameter of < 30mm and type B was more active than type A in each of the same size. Percentage of CaCO3 in the gut during maintenance in the laboratory was 73% and the other 27% consist of organic and inorganic materials. Daily bierosion E. mathaei type A ≥ 30 mm 166.70 mg.day-1 , type A < 30 mm 77.78 mg.day-1 , type B ≥ 30 mm 126.30 mg.day-1 , type B < 30 mm 116.17 mg.day-1. Daily bioerosion rate E. mathaei was influenced by the type, species, speed of grind, and the size of the sea urchin. Keywords: size; Echinometra mathaei; bioerosion; reef flat


2020 ◽  
Vol 161 ◽  
pp. 105106
Author(s):  
Tatiana Miura Pereira ◽  
Karla Giavarini Gnocchi ◽  
Julia Merçon ◽  
Bruna Mendes ◽  
Barbara Martins Lopes ◽  
...  

2013 ◽  
Vol 50 (4) ◽  
pp. 111-118 ◽  
Author(s):  
Roxanne Dominique Haverkort-Yeh ◽  
Clyde S. Tamaru ◽  
Kelvin Dalauta Gorospe ◽  
Malia Ana J. Rivera

Sign in / Sign up

Export Citation Format

Share Document