Judul: Kontribusi terumbu buatan (Reef Ball) dalam pengembangan minawisata bahari di Wilayah Pesisir Ratatotok Sulawesi Utara
Abstrak: Impacts of artificial reefs (reef ball) and its potential for the development of fisheries and marine tourism is presented in this paper. The study was conducted to analyze the ecological and economic impacts of artificial reefs, to assess the suitability of the area for the development of marine tourism and fisheries, and to formulate integrated management strategies of artificial reef region, in Ratatotok coastal areas, North Sulawesi, from 2009 to 2011. The results showed that artificial reefs presence for about 11 years has affected the ecological and economic coral reef ecosystems. It is showed that by using Scenic Beauty Estimation (SBE) method the location with coral reef has higher visual level preference than the locations without the artificial reef. Regional conformity assessment results showed that the location is suitable as marine tourism area and small-scale coral reefs fisheries. Moreover, integrated management strategies appropriate to support the development of marine tourism and fisheries in the region and boost the economy of coastal communities while still maintaining the sustainability of coral reef ecosystems.
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Judul: Pemanfaatan Sumberdaya Terumbu Karang untuk Perikanan Tangkap dan Pariwisata di Pulau Pasi, Kabupaten Kepulauan Selayar, Provinsi Sulawesi Selatan
Abstrak: Coral reef ecosystem has been crucial for the community near the ecosystem especially in fisheries and tourism sector. Coral reef condition plays an important role not only for ecological but also economic sustainability. The study is tried to apply valuation technic for the aim of knowing the ecological condition and valuing coral reef ecosystem focussing on utility of fisheries and tourism in Pasi Island. Coral condition in Pasi Island is influencing those sectors, whereas the impact of MPA could increase the coral cover and fish abundancy that also influence the fisheries and tourism sectors. The possibility to implement entrance fee is tried to evaluate by asking tourist willingness to pay as a form of community awareness. Based on the effect of production method and travel cost method, we calculate economic value from fisheries about Rp. 2 665 016 072/ha/year and economic value from tourism about Rp. 53 700 760.31/ha/year. Using contingent valuation method, willingness to pay for entrance fee is Rp. 23 653.65,-/ person, therefore the benefit from entrance fee implementation worth over 146 million Rupiah per year. MPA implementation is observed have a positive effect on fisheries economic value.
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Judul: Cycle Hamilton pada Graf Lengkap, Graf Regular, dan Graf 2-Connected 4-Regular Berorder Kurang dari Sepuluh
Abstrak: Suatu graf disebut graf Hamilton apabila graf tersebut memuat cycle Hamilton, yaitu cycle yang melewati setiap vertex tepat satu kali. Menentukan keberadaan cycle Hamilton pada suatu graf dapat menggunakan syarat cukup yang berupa teorema-teorema yang telah diperkenalkan sejak tahun 1950-an. Beberapa syarat cukup yang dibahas dalam karya ilmiah ini adalah syarat cukup yang berhubungan dengan graf lengkap dan graf regular. Suatu graf lengkap berorder 𝑛������ ≥ 3 dan graf r-regular berorder 𝑛������ ≤ 2𝑟������ + 1 merupakan graf Hamilton, Karena kedua graf tersebut memuat cycle Hamilton. Selanjutnya, syarat cukup tersebut digunakan untuk menentukan keberadaan cycle Hamilton pada graf 2-connected 4- regular berorder kurang dari 10.
Keyword: graf Hamilton, graf regular, graf lengkap, graf 2-connected 4-regular