Jumlah populasi rajungan di wilayah perairan Laut Jawa, Kabupaten Sukamara mulai mengalami penurunan. Terjadinya penangkapan rajungan secara terus-menerus tanpa memperhatikan ekosistem menjadi penyebab utama terhadap penurunan populasi rajungan. Penelitian ini dilakukan untuk mengetaui bioekologi, kelimpahan dan pola distribusi rajungan di perairan laut Jawa, Kabupaten Sukamara. Penelitian ini dilakukan pada bulan Mei sampai Oktober 2019. Pengambilan sampel penelitian dilakukan pada 4 stasiun penelitian menggunakan pukat. Data yang dikumpulkan adalah jumlah individu, lebar rajungan, rasio jenis kelamin, kelimpahan, dan pola distribusi rajungan. Hasil penelitian menunjukkan kelas ukuran lebar rajungan berdasarkan hasil penelitian didominasi oleh rajungan dewasa (> 12 cm). Rasio kelamin rajungan didominasi oleh rajungan jantan. Rajungan betina yang sedang bertelur, terutama pada bulan September-Oktober menunjukkan jumlah peningkatan. Kelimpahan rajungan tertinggi pada stasiun 1 dan terendah pada stasiun 4. Kelimpahan tertinggi di bulan Mei, Juli dan September pada stasiun 1, 2, 3, dan tertinggi di bulan Juni dan Agustus pada stasiun 4.

Abstract. Fresh Water and salt are the most important necessities in human life. The scarcity and the difficulty to get fresh water and salt became main problems that emerge in many places such as for people who live in coastal areas and small islands where their main source of water and salt is the sea water. In order to obtain fresh water, people needs to process seawater into fresh water and salt. The term of fresh water used here means water which is free from dirt, bacteria, and other substances that are harmful for human health. To process the sea water into fresh water and salt has been done by distillation technic. The distillation technic requires heat to evaporate seawater before condensed and produce clean water. Heat for distillation process can be derived from a variety of sources, one of them is solar energy. The purpose of this study is to compare between a flat plate with one slope cover and two slope cover to produce fresh water and salt. The distilled water was tested in laboratory to determine whether the quality of water and salt after distillation meets the consumable requirements. The working principle of the distillator is by filled the basin with sea water and then heated with solar power. The water will be evaporated and due to the different of temperature between inside and out side of cover so that the condensation accurs at inside of cover. The condensed water will flow through surface of glass cover and then the distilled freshwater gathered in storage. The process will continue until water runs out and creates salt crystals in the basin. Solar distillation testing by using one slope cover with a size of 140 cm x 220 cm produce 3,482 ml / day of clean water and 322 grams of salt / 4 days at average intensity of 697 W/m 2 . While solar distillation by using two-slope cover with size of 80 cm x 50 cm produce 1,551 ml clean water/day and 199.9 grams of salt / 4 days.