KAJIAN KARAKTERISTIK SEDIMEN TERHADAP POLA DISTRIBUSI DAN STRUKTUR KOMUNITAS DIATOM BENTIK DI EKOSISTEM LAGUNA SEGARA ANAKAN CILACAP

Abstract

STUDY ON SEDIMENT CHARACTERISTIC TOWARD DISTRIBUTION PATTERN AND COMMUNITY STRUCTURE OF BENTHIC DIATOM IN THE ECOSYSTEM OF SEGARA ANAKAN LAGOON, C1LACAP. Ria Azizah,TN.; Widianingsih; Ita dan Hadi Endrawati. 2005. 29 Page Mangrove is one of ecosystem has function for nursery ground, nutrient trap, spwaning ground and metabolism activity. So there rz, some organisms which capable to play an important role in order to maintance mangrove productivities and has important role for photosynthesis and food chain. Because of importance role of bentic diatom on the benthic ecosystem, so need to know more about the distribution pattern of benthic diatom through measuring of abundance of benthic diatom on mangrove ecosystem which has been related with sediment characteristic. The aims of present work are to determine relationship between sediment characteristic with abundance of benthic diatom in the mangrove ecosystem. The research had been done on June — August 2005 on the Segara Anakan Laguna The sediment samplings were done with using core which has diameter 29 mm.). Sampling process have done with coresampler taken from 1 cm uppermost of sediment. The samples were preserved by 4 % Formaldehyde and borax. Separating diatom from sediment was conducted in laboratorium using Snoeijs method (Snoeijs et al., 1990). Result of this research showed that on Sapuregel area had been found 23 genera of benthic diatom and 14 families. Whereas, on the Klaces area had been found 25 genera of benthic diatom and 15 families. According to regression analysis, the result showed that the relationship between abundance of benthic diatom value and grain size sediment, Which has been negative correlation not only for June and July but also for August 2005 (on the Klaces area, the value of R2 = 0,3917 for June; R2 = 0,4186 for July and le = 0,4636 for August). Whereas on the Sapuregel area, the value of regression correlation for June R2 = 0,3582; for July R2 = 0,3751 and for August R2 = 0,4012. Where progressively increasing percentage of item grain size measure, hence progressively lower the value of abundance of benthic diatom which indentified on the upper most layer on sediment KAMAN KARAKTERISTIK SEDIMEN TERHADAP POLA DISTRIBUSI DAN STRUKTUR KOMUNITAS DIATOM BENTIK DI EKOSISTEM LAGUNA SEGA1RA ANAKAN CILACAP. Ria Azizah,TN.; Widianingsih; Ita Riniatsih; dan Hadi Endrawati. 2005. 29 Halaman. Mangrove merupakan mutely wound, penyedia nutrient, tempat pemijahan dan aktivitas metabolisme berbagai organisme, maka terdapat beberapa organisme yang mampu met ainkan peranan dalam menjaga produktivitas mangrove day) berperan dalam fotosihtesa serta rantai makanan. Diantaranya adalah mikroalga yang hidup di subtrat mangrove khususnya diatom bentik, maka perlu kiranya untuk mengetahui lebih jauh tentang pola distribusi kelimpahan diatom bentik di wilayah mangrove yang dikaitkan dengan karakteristik sedimen. Penelitian ini bertujuan untuk mengetahui hubungan antara karakteristik sedimen dengan kelimpahan diatom bentik perairan mangrove . Pengambilan sample dilaksanakan pada bulan Juni — Agustus 2005 di perairan Segara Anakan. Pengambilan sampel sedimen dilakukan dengan menggunakan tabung core berdiameter 29 mm. Pemisahan diatom bentik dilakukan di laboratorium dengan menggunakan metode Snoeijs et al (1990). 1-lasil penelitian menunjukkan bahwa di wilayah Sapuregel ditemukan 23 gebus Diatom bentik dengan 14 famili. Selanjutnya di Klaces ditemukan 25 genus diatom bentik dengan 15 famili. Bel dasarkan analisa regresi terlihat adanya keterkaitan antara kelirnpahan diatom bentik dengan grain size sedimen, memiliki korelasi yang negatif baik untuk bulan Juni, Juli dan Agustus 2005 (R2 = 0,3917; R2 = 0,4186 ; dan R2= 0,4636) untuk wilayah Maces. Sedangkan untuk wilayah Sapuregel nilai korelasi regresi untuk bulan Juni (R2 = 0,3582); untuk Juli (R2 = 0,3751) dan untuk bulan Agustus nilai R2 = 0,4012. Dengan demikian semakin bertambahnya prosentase ukuran butiran, maka semakin rendah nilai kelimpahan diatom bentik yang teridentifikasi di lapisan teratas sedimen.