Beberapa Aspek Biologi Ikan Beronang (Siganus Vermiculatus) Di Perairan Arakan Kecamatan Tatapaan Kabupaten Minahasa Selatan

BEBERAPA ASPEK BIOLOGI IKAN BERONANG (Siganus vermiculatus) DI PERAIRAN ARAKAN KECAMATAN TATAPAAN KABUPATEN MINAHASA SELATAN1 Suleiman Tuegeh2, Ferdinand F Tilaar3, Gaspar D Manu3 ABSTRACT One of the goals in the development of fisheries and marine biological resources is the formation of water conservation. Marine biological resources are considered to have significant economic value is rabbitfish. Availability of rabbitfish throughout Indonesia is still relatively large, this is possible because the Rabbitfish is a part of the coral reef ecosystem. The existence of rabbitfish (Siganus vermiculatus) in the waters of Arakan is a source of considerable revenue to help the fishermen in the village of Arakan. Market demand for these fish make the fishermen increasing the catch of rabbitfish in the waters of Arakan. As an initial action on the prevention of exploitation of this resource, one of the main things is the availability of biological information. This study is implemented with the aim to find out some biological aspects of Rabbitfish (Siganus vermiculatus), the L-W relationship, the pattern of growth, condition factor, gonad maturity index, gonado index and the sex ratio. Keywords: Biological aspect, rabbitfish ABSTRAK Salah satu tujuan dalam pembangunan perikanan dan kelautan adalah pembinaan kelestarian sumberdaya hayati perairan. Sumberdaya hayati laut yang tergolong mempunyai nilai ekonomis penting adalah ikan beronang. Ketersediaan dari ikan ini di seluruh Indonesia masih relatif besar, hal ini dimungkinkan karena ikan beronang merupakan bagian dari ekosistem terumbu karang. Keberadaan ikan beronang (Siganus vermiculatus) di perairan Arakan merupakan sumber pendapatan yang cukup membantu para nelayan di Desa Arakan. Permintaan pasar akan ikan beronang ini membuat para nelayan semakin giat dalam menangkap ikan beronang yang ada di perairan Arakan. Sebagai tindakan awal pencegahan eksploitasi pada sumberdaya ini salah satu hal utama ialah tersedianya informasi aspek biologi. Penelitian ini dilaksanakan dengan tujuan untuk mengetahui beberapa aspek biologi ikan beronang (Siganus vermiculatus) yaitu hubungan panjang berat, pola pertumbuhan, faktor kondisi, indeks kematangan gonad (IKG), indeks gonad (IG) dan perbandingan jenis kelamin

Seagrass Community At Kampung Ambong’s Water East Likupang Subdistrict, North Minahasa Regency

This Research is done at Kampung Ambong’s Water East Likupang Subdistrict, North Minahasa Regency. The aim of this research is to know the type composition of seagrass and to analyzed soliding, dominatting index, various index, index of spreadness. The data taken with the line transect method. The transect placement divided become 3 transect line that  located it uphold straight of beach line  each of them 95 meter long. Meanwhile the space between one transect to another (second and third) each 100 m.Meanwhile the space between one transect to another (second and third) each 100 m. All of them identified as : Cymodocea rotundata, Syringodium isoetifolium, Halophila decipiens, Halodule pinifolia, Cymodocea serrulata, Enhalus acoroides, Halphila minor,  Thalassia hempricii, Halodule uninervis, Halophila spinulosa. From the soliding each species show the highest score which is Cymodocea rotundata 2608 individu/m2, Syringodium isoetifolium 816 individu/m2, Halophila decipiens 420 individu/m2, Halodule pinifolia 292 individu/m2, Cymodocea serrulata 268 individu/m2, Enhalus acoroides 260 individu/m2, Halophila minor 224 individu/m2, Thalassia hempricii 160 individu/m2, Halodule uninervis 124 individu/m2, Halophila spinulosa 20 individu/m2.Whereas dominatting index be obtained 0.3 be in low category. its mean there is no species that to dominate in that water. Various index be obtained 1.65 be in mid category. it show that species community almost in spread condition, because it has the same opportunity.Index of spreadness be obtained 0.72 be in   high category, because it has a mixing seagrass field.Keywords:  community, composition, seagrass soliding. ABSTRAKPenelitian ini dilakukan di Perairan Kampung Ambong Kecamatan Likupang Timur Kabupaten Minahasa Utara.Tujuan dari penelitian ini mengetahui komposisi jenis lamun dan menganalisis kepadatan, indeks dominasi, indeks keanekaragaman, indeks kemerataan.  Pengambilan data dilakukan dengan metode garis transek.  Penempatan transek di bagi menjadi 3 garis transek yang di letakkan tegak lurus garis pantai dengan panjang masing-masing garis transek 95 meter.  Sedangkan jarak antara transek 1 dengan transek yang lain (2 dan 3) masing-masing 100 m. Dari hasil penelitian komposisi jumlah spesies lamun (seagrass) adalah 10. Kesepuluh spesies yang teridentifikasi yaitu: Cymodocea rotundata, Syringodium isoetifolium, Halophila decipiens, Halodule pinifolia, Cymodocea serrulata, Enhalus acoroides, Halphila minor,  Thalassia hempricii, Halodule uninervis, Halophila spinulosa.Kepadatan masing-masing spesies  diperoleh menunjukkan nilai tertinggi yaitu Cymodocea rotundata 2608 individu/m2, Syringodium isoetifolium 816 individu/m2, Halophila decipiens 420 individu/m2, Halodule pinifolia 292 individu/m2, Cymodocea serrulata 268 individu/m2, Enhalus acoroides 260 individu/m2, Halophila minor 224 individu/m2, Thalassia hempricii 160individu/m2, Halodule uninervis 124individu/m2, Halophila spinulosa 20 individu/m2.  Sedangkan indeks dominasi diperoleh 0.3 berada dalam kategori rendah, artinya tidak ada spesies yang mendominasi di perairan tersebut. Indeks keanekaragaman diperoleh 1.65 berada dalam kategori  sedang.  Hal ini menunjukkan bahwa komunitas spesies dalam kondisihampir merata, karena memiliki peluang yang sama. Indeks kemerataan diperoleh 0.72 berada dalam kategori tinggi, karena memiliki padang lamun campuran.Kata kunci : komunitas, komposisi, kepadatan lamun

Growth of Brown Algae, Padina Australis, in the Coastal Waters of Serei Village, West Likupang District, North Minahasa Regency

Marine algae is one resource that has important economic value because it has cagar, carrageen and alginate ontent (Indriani and Sumiarsih, 1999). In the world of science, the word algae comes from the Greek , algor which means cold (Nontji, 2002). Padina australis is a species of marine algae belong to Phaeophyta Division (brown algae) which is commonly found in marine waters, from shallow to deep waters. This algae has a wide transparent brown sheet or filament shape. This study was aimed to observe the growth of algae P. australis by using case study method where samples of Padina algae taken from nature were placed into basket as container for culturing. While the technique used is cultivation using basket; in order to determine the growth, algae was analyzed further by measuring the maximum weight of P. australis living without substrate. Some environmental factors such as temperature, salinity, depth and tides were recorded to see their impact on the growth of P. australis. Serei village is the location of the research on the growth of this P. australis. The result also records that P. australis can only live about three weeks and after that die. The growth of P. australis was greatest in the 8th container weighing 23 gr

Survival estimates of bycatch individuals discarded from bivalve dredges

The fate of released bycatch is an issue of great interest for fisheries research and management. Survival experiments were carried out to assess the survival capacity of animals damaged and discarded during clam dredging operations. Three common bycatch species, two fish (Trachinus vipera; Dicologlossa cuneata) and one crab (Polybius henslowii), were collected during the sorting of catches from a commercial dredging boat. An arbitrary score scale was used to quantify the type and extent of damage to the organisms. Onboard, damaged individuals were placed in tanks containing seawater which were subsequently transferred to the laboratory. Survival experiments were conducted during the subsequent 48h. D. cuneata exhibited the lowest mortality after 48h (54%), followed by P. henslowii (65%) and T. vipera (81%). Despite the magnitude of the percentage mortalities determined, the average number of individuals estimated to die during a 15 minutes tow (standard commercial fishing time) was relatively small: 1.2, 3.24 and 11 for D. cuneata, T. vipera and P. henslowii, respectively. Nevertheless, when these figures are extrapolated to cover all the dredging fleet the impact of this practice on the populations of the species studied can be significant, particulary for D. cuneata

Karakteristik Morfometrik Dan Faktor Kondisi Kerang Totok (Polymesoda Erosa) Di Hutan Mangrove Desa Nusajaya Kecamatan Waslei Selatan Kabupaten Halmahera Timur Maluku Utara

Clam, Polymesoda erosa is species that live in sandy and muddy substrata of mangrove ecosystem. The aims of this study are to look at the relationship of the shell length and width,body thiekness, body weight and organ weight based on class size to determine the growth. The study also was designed to reveal the conditional factor based on the clam class size. The samples were collected during the day at lowest tide in January 2014. The total is 153 individuals of Polymesoda erosa clam were collected during the study. The result shows thare is a strong positive relationship between body lenght and body weight as shown within the regression analysis with intercept (a) = 0,470779, regression coefficient (b) = 0,69095 and correlation coefficient (r) = 0,406357. Based on the r value, it can be concluded that there is strong relationship regarding the length and weight increment as much as 40,63 %

Phytoplankton Composition and Factors of Physics – Chemical Water Depth on Water Lake Tondano

Research on phytoplankton composition and physico-chemical factors of the Central part of Tondano waters was done by taking water samples from the depths of 5 M, 10 M and 20 M, respectively. The purpose of the study was to identify the phytoplankton, determine the species density and diversity index, and the physico-chemical factors of water with depth. Results revealed that 8 species of phytoplantkon were found at 8 m depth dominated by Chlorophyceae (2 species with 228 cells/liter), and Bacillariophyceae (3 species with 168 cells / liter). Thirteen species were recorded at 10 m depth dominated by Clorophyceae (7 species with 1728 cells / liter), and Bacillariophyceae (3 species with 984 cells / liter). Meanwhile, there were 8 species found at 20 m depth dominated by Bacilariophyceae (4 species with 3828 cells / liter) and Chlorophyceae (one species with 84 cells / liter). The results of the analysis of the ecological index at a water depth of 5 m to 20 meters earn variation of species diversity index (H \u27, H\u27miax, H\u27min) with a value of 1779-1039, 1832-1069, 1707-1008), the dominance index (D) with value of 0.204 - 0.4722, and harmony with the index value of 0.7406 - 0.3535.Based on t-test, species diversity index(H) of the phytoplankton at all 5 M depth was not different from that at 10 M), but the spesies diversity index was different between 5 M and 20 M depth and between 10 M and 20 M. The results of measurements of chemical physics parameters of water at a depth of 5 M to 20 M has a range of concentrations (TDS 149- 151 mg / L, DHL 232-234 mg / L, pH 7.2 - 6.79, Total Phosfat 0.0008 - 0.062 mg / L, dissolved Phosfat 0.0 mg / L, Total Nitrogen 0065-0027 mg / L, Ammonia 0031-0012 mg / L, and Nitrate 0.83 - 1.70 mg /

Formal language hierarchy reflects different levels of cognitive complexity

Formal language hierarchy describes levels of increasing syntactic complexity (adjacent dependencies, nonadjacent nested, nonadjacent crossed) of which the transcription into a hierarchy of cognitive complexity remains under debate. The cognitive foundations of formal language hierarchy have been contradicted by two types of evidence: First, adjacent dependencies are not easier to learn compared to nonadjacent; second, crossed nonadjacent dependencies may be easier than nested. However, studies providing these findings may have engaged confounds: Repetition monitoring strategies may have accounted for participants’ high performance in nonadjacent dependencies, and linguistic experience may have accounted for the advantage of crossed dependencies. We conducted two artificial grammar learning experiments where we addressed these confounds by manipulating reliance on repetition monitoring and by testing participants inexperienced with crossed dependencies. Results showed relevant differences in learning adjacent versus nonadjacent dependencies and advantages of nested over crossed, suggesting that formal language hierarchy may indeed translate into a hierarchy of cognitive complexit

Some exact non-vacuum Bianchi VI0 and VII0 instantons

We report some new exact instantons in general relativity. These solutions are K\"ahler and fall into the symmetry classes of Bianchi types VI0 and VII0, with matter content of a stiff fluid. The qualitative behaviour of the solutions is presented, and we compare it to the known results of the corresponding self-dual Bianchi solutions. We also give axisymmetric Bianchi VII0 solutions with an electromagnetic field.Comment: latex, 15 pages with 3 eps figure