IDENTIFIKASI SPONS BERDASARKAN TUTUPAN KARANG DI PERAIRAN SOMBU TAMAN NASIONAL WAKATOBI

Spons merupakan hewan multiseluler paling primitif yang hidup diberbagai tipe perairan mulai dari tawar, payau, dan laut. Biota ini hidup di dasar perairan dan biasanya menempel pada substrat keras seperti batu atau karang dan berkompetisi dengan organisme penempel lainnya untuk memperoleh ruang dan makanan. Penelitian ini bertujuan untuk mengetahui keanekaragaman dan kepadatan spons berdasarkan tutupan karang. Penelitian ini dilaksanakan pada bulan Desember 2020 – Juli 2021, di Perairan Sombu Taman Nasional Wakatobi. Pengambilan data spons dilakukan dengan menggunakan metode belt transect dengan panjang line transect 50 m dengan lebar 4 m pada kedalaman 3 m (reef flat) dan 7 m (reef slope) pada masing-masing stasiun. Data diambil bersama dengan tutupan karang menggunakan metode line intercept transect (LIT) dengan panjang line transect 50 m pada kedalaman yang sama dengan data spons. Hasil penelitian didapatkan bahwa keanekagaraman hayati spons yang ditemukan dilokasi penelitian yaitu sebanyak 2 kelas, 19 famili dan 23 genus. Yakni keanekaragaman jenis spons tertinggi yaitu pada stasiun I sebesar 20 genus, serta kepadatan spons tertinggi sebesar 0,18 individu/m2 terdapat pada genus Spheciospongia sp., kepadatan spons tertinggi berdasarkan stasiun terdapat pada stasiun I zona reef slope yaitu dengan nilai 0,32 individu/m². Persentase tutupan karang pada stasiun I dan II masuk dalam kondisi baik, sedangkan pada stasiun III masuk dalam kondisi sedang. Keanekaragaman dan kepadatan spons dipengaruhi adanya keberadaan terumbu karang, sehingga keberadaan tutupan karang yang tinggi menyebabkan melimpahnya pertumbuhan spons.Kata Kunci : Keanekaragaman, Kepadatan, Spons, Terumbu Karang

DOMINASI GENERA KARANG KERAS (HARD CORAL) DI PERAIRAN DESA TANJUNG TIRAM, KAB. KONAWE SELATAN

Ekosistem terumbu karang di Desa Tanjung Tiram memiliki sumberdaya yang beranekaragam dan berlimpah. Namun dalam beberapa dekade terakhir, keberadaannya terancam oleh kegiatan penangkapan ikan yang tidak ramah lingkungan. Penelitian ini bertujuan untuk mengetahui dominasi genera karang keras dan persentase tutupan karang hidup serta hubungan faktor lingkungan dengan sebaran kondisi terumbu karang di perairan Desa Tanjung Tiram. Penelitian ini dilaksanakan pada bulan September 2020. Hasil penelitian ini ditemukan 3 genera dominasi yaitu Porites, Fungia dan Favites dimana Porites merupakan genus karang yang paling dominan ditemukan di area reef slope dan reef flat. Secara keseluruhan persentase tutupan karang hidup Perairan Tanjung Tiram berada di bawah 60%. Semakin dalam perairan presentase tutupan karang hidup makin rendah dan patahan mendominasi.Kata kunci: Dominasi, Karang Keras, Tanjung Tiram.

Massive cryptic microbe-sponge deposits in a Devonian fore-reef slope (Elbingerode Reef Complex, Harz Mts., Germany)

A massive occurrence of microbial carbonates, including abundant sponge remains, within the Devonian Elbingerode Reef Complex was likely deposited in a former cavity of the fore-reef slope during the early Frasnian. It is suggested that the formation of microbial carbonate was to a large part favored by the activity of heterotrophic, i.e., sulfate-reducing bacteria, in analogy to Quaternary coral reef microbialites. The Elbingerode Reef Complex is an example of an oceanic or Darwinian barrier reef system. In modern barrier reef settings, microbialite formation is commonly further facilitated by weathering products from the central volcanic islands. The Devonian microbialites of the Elbingerode Reef Complex occur in the form of reticulate and laminated frameworks. Reticulate framework is rich in hexactinellid glass sponges, the tissue decay of which led to the formation of abundant micrite as well as peloidal and stromatactis textures. Supposed calcimicrobes such as Angusticellularia (formerly Angulocellularia) and Frutexites, also known from cryptic habitats, were part of the microbial association. The microbial degradation of sponge tissue likely also contributed to the laminated framework accretion as evidenced by the occurrence of remains of so-called “keratose” demosponges. Further typical textures in the microbialite of the Elbingerode Reef Complex include zebra limestone, i.e., the more or less regular intercalation of microbial carbonate and cement. Elevated concentrations of magnesium in the microbialite as compared to the surrounding metazoan (stromatoporoid-coral) reef limestone suggests that the microbialite of the Elbingerode Reef Complex was initially rich in high-magnesium calcite, which would be yet another parallel to modern, cryptic coral reef microbial carbonates. Deposition and accretion of the microbialite largely occurred in oxygenated seawater with suboxic episodes as indicated by the trace element (REE + Y) data.

HARD CORAL (SCLERACTINIA) RECRUITMENT BASED ON THE GEOMORPHOLOGY ZONE IN BINTAN ISLAND WATERS, RIAU ISLANDS

The health of coral reef ecosystems can be seen through the emergence of coral recruitment. Aim of this research was to compared the scleractinia coral recruitment list based on genus, life form, and variations in size of the scleractinia coral recuit in the waters of Kampung Baru Lagoi and Teluk Bakau Village, Bintan Regency by geomorfology zone. The research was conducted using a Purposive sampling method in consideration of the presence of scleractinia coral in reef flat and reef slope areas using a 1x1 m square frame mounted along a 70 m transverse line parallel to the shoreline. Research has found 164 colonies of 24 genus dominated by Favia and Favites. Based on the most extensive life form of Coral encrusting and Coral massive variations in size 4.5-6 cm or medium category. The results of t test showed that the geomorphological differences in the research locations did not have a significant impact on the abundance of corals recruitment

IDENTIFIKASI ANEMON DI DAERAH TERUMBU KARANG PERAIRAN KASWARI, TAMAN NASIONAL WAKATOBI

Anemon merupakan salah satu hewan laut dari filum Cnidaria atau Coelenterata yang sering dimanfaatkan sebagai penghias akuarium dan sumber makanan bagi masyarakat pesisir Wakatobi. Berdasarkan literature, anemon telah berhasil di identifikasi sebanyak 12 jenis tersebar di seluruh dunia, 10 jenis diantaranya terdapat di Indonesia. Penelitian ini bertujuan mengetahui keanekaragaman dan kelimpahan anemon pada daerah terumbu karang di perairan Desa Kasuari, Wakatobi. Pengumpulan data dilaksanakan selama 2 bulan yaitu Februari – Maret 2020. Metode pengumpulan data menggunakan metode belt transect yaitu dengan luas 200m² dengan 3 kali ulangan untuk mewakili area reef flat dan reef slope. Jenis anemon yang ditemukan di perairan Desa Kaswari yaitu Heteractis crispa dan Heteractis malu. Kelimpahan anemon di perairan Desa Kaswari pada stasiun Reef Flat adalah 0,045 individu/m² sedangkan pada stasiun Reef Slope adalah 0,065 individu/m². Hasil Uji-T diperoleh nilai t-hitung (-2.000) ≤ t-tabel (2.776). Artinya bahwa tidak terdapat perbedaan yang nyata antara nilai rata-rata individu anemon pada daerah reef flat dan reef slope meskipun berada pada zona terumbu karang yang berbeda.Kata Kunci: Kelimpahan anemon, Terumbu karang, Kaswari.

Coral Cover and Diversity Life form in Different Geomorpholgy Zone at Kampung Baru Waters, Bintan Island

The purpose of this study was to compare the percentage of cover conditions, diversity index, uniformited index and dominance index of life form coralin the zones reef flate and reef slope in Kampung Baru Lagoi, Bintan Regency. This research was conducted using the method Line Intersept Transect (LIT) with the line transect length used was 30 meters, three replications with a gap of 5 meters. The results showed, at point station 1 in the zone flate Reef the percentage of live coral cover was 36,92% are categorized as moderate. Forms the coral growth Life form were found as many 9 types of Life form hard corals namely ACB, ACT, ACE, ACS, ACD, CB, CM, CE, CS with a diversity index of 2,53 are categorized as moderate, a uniformited index of 0,80 are categorized as high, and a dominance index of 0,22 are categorized as low. At the point station 2 in the zone slope Reef the percentage of live coral cover was 50,44% are categorized as good. Forms of coral growth (Life form) were found as many as 8 types of Life form hard corals namely ACT, ACE, CB, CM, CE, CS, CF and CMR, with a diversity index of 2,13 are categorized as moderate, a uniformited index of 0,71 are categorized as high, and a dominance index of 0,30 are categorized as low.

First record of the cryptic fishes Ptereleotris calliura (Gobiidae) and Liopropoma rubre (Serranidae) from the Veracruz reef system in Mexico

Based on several in situ observations, the species Ptereleotris calliura (family Gobiidae) and Liopropoma rubre (family Serranidae) are added to the taxonomic fish inventory of the Veracruz reef system, Mexico. While P. calliura was found on sandy substratum in the lagoon, L. rubre was detected on the reef slope. With their addition, the checklist of reef fishes in the Veracruz reef system is expanded to 479 species. Given these findings, we predict that additional survey efforts (beyond visual transects) will reveal more previously unrecorded species of cryptic fishes in the Veracruz reef system.

Fossil molluscan fauna reflects zonation of a Late Pleistocene reef of the Red Sea

<p>Many studies focus on modern coral reefs and their associated invertebrate fauna, but not much is known about the paleoecology and diversity of molluscs of Late Pleistocene coral reefs, which were formed during the last interglacial MIS5e. This study is investigating the molluscan assemblage of a Late Pleistocene coral reef in southern Egypt, at the locality Sharm El Luli, in the area of Marsa Alam. The locality is characterized by a variety of reef- and reef associated habitats, including a reef flat, reef slope, a patch reef, and soft bottoms of a lagoon and in the backreef area. We quantitatively and qualitatively sampled 10 sites with a total of 79 samples and collected 2126 shells, which belong to 177 taxa, mostly identified to the species level.   Most taxa were found with the qualitative sampling approach. The most abundant bivalves taxon was the epifaunal, encrusting <em>Chama </em>spp., the most abundant gastropod species was the cerithiid <em>Rhinoclavis vertagus</em>. Regarding the life habitats most bivalve species are infaunal filter feeders, while most gastropods are epifaunal carnivores.    Alpha diversity is highest in the coral patch and in the upper reef region, which implies the reef slope, the reef flat as well as the transition between reef slope and the lagoon. Preliminary statistical results suggest a division in coral-patch, lagoon and backreef as well as a cluster of upper-reef habitats. From these two broad environments can be distinguished: hard bottoms associated to reefs and reef-associated soft bottom environments. The former are best characterized by encrusting taxa such as <em>Chama </em>spp. and <em>Spondylus </em>spp., and by <em>Tridacna maxima</em> and <em>Perigylypta </em>spp., which are well-known reef associates. Gastropods in this environment are predatory conids and cypraeids. All of these species live on - or occur cryptically in - structured hard bottoms. Reef associated-soft bottom environments are best characterized by infauna, such as the tellinid <em>Quidinipagus palatam</em> and the lucinids <em>Anodontia kora</em> and <em>Pillucina vietnamica</em>. Furthermore, many soft bottom gastropod species such as the strombid <em>Gibberulus gibberulus albus</em>, the cerithiid <em>Rhinoclavis vertagus</em>, both with an herbivorous diet, and the nassariid <em>Nassarius fenistratus</em>, a scavenger, can be found here.  A comparison with modern datasets from the Red Sea indicates strong similarities in faunal composition and habitat diversity between fossil and recent reefs.  Furthermore, our preliminary results suggest that Late Pleistocene molluscan assemblages can aid in reconstruction of associated fossil reef habitats. </p>