No abstract

Ampana City, Tojo Una-Una Regency has the potential of marine tourism and the area also faces a serious threat from the litter that can affect aesthetic value, reduce the quality of waters, intervention to normal systems in the environment. Sampling to the beach in general representative locations in Malotong Beach (area of 100 x 25 m2), and Bailo Beach (100 x 10 m2). The sampling units in the transect plots are 5 plots covering 25 m2 (plot size 1 x 1 m2) randomly determined. The next procedures are the collection and classification of litter. The composition and density of the type of litter are distinguished for meso (0.5cm-2.5cm) and macro (> 2.5cm) litter. The results showed that the type and abundance of the litter that generally comes from recreational activities of beach visitors and household litter. In general, meso and macro litter were found in Malotong Beach as many as 25 types, and in Bailo Beach as many as 35 types. The presence of litter on the coast and the sea threatens life on the Coast of Ampana City. Today’s public awareness is needed to change habits and give more respect to their environment.

The quality of seaweed Kappaphycus alvarezii type is determined by the content of carageenan. This research is aimed to assess the relationship between season and carrageen content of K. alvarezii seaweed. The design of this research is explanatory reseach by placing the location of cultivation on four sides of the island that is carried out in two seasons, namely the rainy season that lasts between November to February and the dry season between July to October. The environmental parameters measured were nitrate, phosphate, salinity and current velocity. Parameter measurements were performed on a weekly basis during the study, while carrageen was measured at the beginning of the study, second week, fifth week and seventh week. The results of partial seasons were significant for seaweed admixture values. The influence of interaction between station and season with the partial influence of station is not significant to K. alvarezii. This is significant in the absence of extreme changes between stations in a given time with relatively homogenous values at the four observation stations. The average of carageenan in rainy season (40.756%) significantly differed lower compared with dry season (49.063%). The relationship between seaweed carageenan with environmental parameters follows the linear equation: Y =-68.780 + 13.869 Nitrate + 44.316 Phosphate + 2.923 Salinity + 0.87 Flow (R2 = 0.976). It can be concluded that the season is very influential on the production of carageenan and environmental parameters have a positive effect on carageenan. To obtain high carragenan production, it is expected that the cultivation of K. alvarezii will be done during dry season.

Penelitian sebelumnya telah berhasil mengisolasi, dan sekuens basa nukleotida mRNA penyandi FAMeT Scylla olivacea. Beberapa penelitian menuliskan bahwa urutan mRNA penyandi FAMeT memiliki perbedaan pada spesies krustasea. Tujuan penelitian untuk mengetahui jarak kekerabatan S. olivacea dengan krustasea lainnya berdasarkan sekuen mRNA penyandi FAMeT. Kesamaan sekuen mRNA penyandi FAMeT menunjukkan beberapa krustasea yang memiliki kemiripan dengan sekuen mRNA FAMeT S. olivacea. Analisis pohon filogeni menunjukkan adanya 2 klasterkekerabatan mRNA penyandi FAMeT S. olivacea pada cabang yang sama dengan 2 spesies kepiting lainnya: S. serrata dan S. paramamosain. Selain pada genus Scylla, ditemukan pula pada Portunus trituberculatus dan P. pelagicus serta udang sungai Macrobrachium rosenbergii. Temuan tersebut menunjukkan bahwa kepiting S. olivacea monofiletik dengan 2 kepiting bakau lainnya, yaitu rajungan serta udang sungai M. rosenbergii. Sehingga menggambarkan hubungan kekerabatan yang sangat dekat secara genetik. Sementara pada cabang ke 2 terdiri atas krustasea jenis udang-udangan seperti Homarus americanus, Cherax quadricarinatus, Fenneropenaeus merguiensis, Metapenaeus ensis dan Litopenaeus vannamei.

Lobster air tawar (Cherax quadricarinatus) merupakan salah satu organisme yang mengkomsi pakan dengan cara mencabik-cabiknya. Semakin lama pakan tersebut dikonsumsi semakin besar peluang kandungan nutrient dalam pakan mengalami pencucian/leaching. Penelitian ini bertujuan untuk membandingkan pertumbuhan lobster (C. quadricarinatus)  yang diberi pakan buatan dalam bentuk pakan basah (kenyal) dan kering. Juvenil lobster air tawar (dengan bobot 4,47±0,77g) sebelum diberi perlakuan terlebih dahulu diadaptasikan baik pada pakan maupun pada media pemeliharaan. Penelitian ini mengujikan dua perlakuan yakni pakan basah (kenyal) dan kering. Setiap perlakuan diberi 5 kali ulangan. Hasil penelitian menunjukkan bahwa laju pertumbuhan spesifik harian, pertumbuhan bobot individu, tingkat kelangsungan hidup, serta efisiensi pakan untuk perlakuan pakan basah dan kering masing-masing secara berurut sebesar 0,47 %/hari; 0,77g; 90%; 51,57% dan 0,32 %/hari; 0,48g; 80%; 39,01%. Perlakuan yang memberikan nilai lebih tinggi pada lobster (C. quadricarinatus) yakni pemberian pakan basah (kenyal).