Serdiati, Novalina (2019) Karakterisasi Ikan Padi Oryzias Nigrimas (Kottelat, 1990) Sebagai Upaya Pengelolaan Ikan Endemik Di Danau Poso Sulawesi Tengah. Doctor thesis, Universitas Brawijaya.
Abstract
Ikan padi Oryzias nigrimas yang termasuk ke dalam famili Adrianichthyidae merupakan salah satu ikan endemik di Danau Poso Sulawesi Tengah, yang kini statusnya tergolong rawan punah (vulnerable species). Informasi mengenai ikan padi sangat terbatas, sementara populasi ikan ini semakin menurun akibat introduksi spesies asing, perluasan pemukiman, pembukaan lahan pertanian dan limbah rumah tangga. Oleh karena itu diperlukan informasi karakter ikan padi di habitat alaminya sehingga dapat memberikan gambaran tentang kemampuan ikan padi dalam melangsungkan kehidupan agar kelestarian populasi ikan endemik padi dapat berkelanjutan. Untuk itu perlu dilakukan penelitian yang bertujuan (1) mengidentifikasi spesies ikan padi di Danau Poso berdasarkan karakter morfologi dan molekuler; (2) menganalisis karakteristik biologi ikan padi di Danau Poso; (3) menganalisis beberapa parameter lingkungan perairan habitat ikan padi di Danau Poso Kegiatan penelitian dilakukan setiap bulan selama 12 bulan dari bulan Mei 2017 sampai bulan April 2018 di perairan Danau Poso, Sulawesi Tengah. Metode penelitian yang digunakan adalah survey deskriptif. Stasiun penelitian ditetapkan dengan mempertimbangkan karakteristik perairan Danau Poso berdasarkan habitat, kondisi stasiun untuk operasional sampling dan stasiun mewakili keragaman habitan ikan padi. Berdasarkan pertimbangan ini ditetapkan 3 stasiun penelitian yaitu: perairan Watudilana, perairan desa Tolambo dan perairan desa Taipa. Karakteristik ikan padi dengan melakukan kajian morfologi, morfometrik dan meristik serta kajian genetik. Kajian karakteristik biologi meliputi tingkat kematangan gonad, indeks kematangan gonad, nisbah kelamin, ukuran ikan pertama kali matang gonad dan hubungan panjang berat. Karakteristik habitat dengan melakukan pengukuran kualitas air dan kelimpahan plankton. Hasil identifikasi berdasarkan karakter taksonomik, meliputi karakter morfologi kualitatif (pola warna), morfologi kuantitatif (morfometrik dan meristik) dan secara molekuler dengan menggunakan Gen Cythocrome Oxidase subunit I (COI) pada DNA mitokondria menunjukkan bahwa ikan padi yang ada di danau Poso teridentifikasi sebagai Oryzias nigrimas Secara biologi, ikan padi di Danau Poso dapat memijah sebanyak 5 kali dalam setahun dengan puncak pemijahan pada bulan November 2017. Berdasarkan nilai IKG, memberikan informasi mengenai aktivitas pematangan gonad ikan padi terjadi pada bulan Juni dan Agustus 2017. Nilai nisbah kelamin pada ikan padi di Danau Poso sebesar 0,7714 dengan perbandingan ikan jantan dan betina sebesar (0,77;1,00). Untuk ukuran pertama kali matang gonad, ikan padi di Danau Poso memiliki nilai Lm = 50,77 mm pada ikan jantan dan Lm = 47,45 mm pada ikan betina. Ikan padi di Danau Poso termasuk dalam ikan omnivora cenderung herbivora dengan kisaran Index of Prepoderance rata-rata 57,73 - 70,75% untuk phytoplankton dan 29,25 - 42,27% untuk zooplankton. Pola pertumbuhan allometrik negatif dengan pertumbuhan panjangnya lebih cepat dari pada pertumbuhan berat badan. xiii Untuk parameter kualitas air di Danau Poso tergolong dalam keadaan normal apabila dikaji melalui nilai kualitas suhu (ºC), kecerahan (m), DO (mg/L), dan pH dengan nilai curah hujan bulanan tertinggi pada bulan Mei 2017, 367,5 mm), Oktober-Desember 2017 (290,5; 265; 366 mm) dan bulan April 2018 (465,5 mm). Keberadaan plankton di Danau Poso terdiri dari 10 jenis spesies zooplankton dan 9 jenis spesies fitoplankton. Kebaharuan yang diperoleh pada penelitian yaitu: ikan padi Oryzias nigrimas yang merupakan ikan endemik di Danau Poso memijah beberapa kali dalam satu musim pemijahan sehingga dapat digolongkan kedalam ikan pemijah berulang (Iteroparity yaitu memijah secara parsial atau beberapa kali dalam setahun) dan merupakan ikan yang mempunyai kebiasaan makanan omnivora cenderung herbivora.
English Abstract
The ricefish Oryzias nigrimas, a member of the Family Adrianichthyidae, is a fish endemic to Lake Poso, Central Sulawesi, Indonesia, with a conservation status of Vulnerable. Information on this ricefish is extremely limited, meanwhile its population abundance is declining due to the introduction of alien species, expansion of human settlements, agricultural land clearing, and the disposal of household waste. Therefore we need information on the characteristic traits of rice fish living in their natural habitat, in order to provide an overview of the survival ability of rice fish to inform sustainable management and conservation of endemic rice fish populations. In this context, research was needed, to meet the following objectives: (1) identification of rice fish species in Lake Poso based on morphological and molecular traits; (2) analysis of the biological characteristics of rice fish on Lake Poso; (3) analysis of several environmental parameters of rice fish habitat in Lake Poso. Research activities were carried out every month in the waters of Lake Poso, Central Sulawesi, Indonesia for a 12 month period from May 2017 to April 2018. A descriptive survey research method was used. The research stations were determined based on specific Lake Poso habitat characteristics, including operational considerations and to ensure stations were representative of the diversity of rice fish habitats around the Lake. Based on these considerations, the following 3 research stations were selected, in the municipal waters of Watudilana, Tolambo village, and Taipa village, respectively. Ricefish characteristics were examined through morphological, morphometric and meristic, and genetic studies. The study on biological characteristics included gonadal maturity levels, the gonad maturity index (GMI), sex ratio, mean size at first maturity (Lm), and length-weight relationships. Habitat characteristics measured included water quality parameters and plankton abundance. Based on taxonomic characters, including qualitative morphological characters (colour patterns), quantitative morphology (morphometric measurements and meristic counts) and molecular markers using the Cytochrome Oxidase subunit I (COI) gene in mitochondrial DNA, the rice fish in Poso lake were identified as Oryzias nigrimas. The biological research showed that ricefish in Lake Poso can spawn up to 5 times a year, with a spawning peak observed in November 2017. The GMI values obtained indicate that gonad maturation in rice fish occurred in June and August 2017. The sex ratio of rice fish in Lake Poso was 0.7714, with a ratio of male to female fish of 0.77:1.00). The mean size at first maturity of rice fish in Lake Poso was Lm = 50.77 mm for males and Lm = 47.45 mm for females. With an average Index of Preponderance in the range of 57.73 - 70.75% for phytoplankton and 29.25 - 42.27% for zooplankton, rice fish in Lake Poso can be classed as omnivorous but predominantly herbivorous. The length-weigh relationship revealed an allometric negative growth pattern, indicating that growth in length tends to be faster than growth in weight. xv The recorded values of water quality parameters in Lake Poso were within ranges classified as normal, including water temperature (ºC), visibility (m), DO (mg / L), and pH. The highest monthly precipitation values were recorded in May 2017 (367.5 mm), October-December 2017 (290.5 mm; 265; 366 mm) and April 2018 (465.5 mm). The plankton identified as being present in Lake Poso comprised 10 species of zooplankton and 9 species of phytoplankton. Novelties gained from this study include the classification of Oryzias nigrimas, a rice fish endemic to Lake Poso, as a iteroparous (a partial spawner or spawning several times in a year), with spawning several times in a spawning season, and as a fish with a predominantly herbivorous omnivorous food habit.
Other obstract
-
| Item Type: | Thesis (Doctor) |
|---|---|
| Identification Number: | DIS/596/SER/k/2019/061903368 |
| Uncontrolled Keywords: | CHORDATA |
| Subjects: | 500 Natural sciences and mathematics > 596 Chordata |
| Divisions: | S2/S3 > Doktor Ilmu Perikanan dan Kelautan, Fakultas Perikanan dan Ilmu Kelautan |
| Depositing User: | Endang Susworini |
| Date Deposited: | 27 Jan 2022 07:53 |
| Last Modified: | 27 Jan 2022 07:53 |
| URI: | http://repository.ub.ac.id/id/eprint/189010 |
Preview |
Text
Novalina Serdiati.pdf Download (5MB) | Preview |
Actions (login required)
 |
View Item |