KONDISI HABITAT DAN EKOSISTEM MANGROVE KECAMATAN SIMPANG PESAK, BELITUNG TIMUR UNTUK PENGEMBANGAN TAMBAK UDANG (Habitat Conditions and Mangrove Ecosystem in Simpang Pesak District, East Belitung for Development of Shrimp Pond)

ABSTRAK Kondisi habitat dan eksosistem mangrove menjadi aspek penting dalam pengembangan usaha perikanan budidaya di wilayah pesisir. Penelitian bertujuan untuk mengkaji kondisi habitat dan ekosistem mangrove berdasarkan kualitas perairan, tanah, dan vegetasi mangrove serta kondisi sosial ekonomi masyarakat. Penelitian dilakukan di empat desa Kecamatan Simpang Pesak Kabupaten Belitung Timur pada bulan April – November 2013. Hasil penelitian menunjukkan kualitas air seperti salinitas 28–30, suhu 27–36 oC, pH 7–7,5, kecerahan 50–70, TSS 11–85 mg/L dan kekeruhan 0,91–46,00 NTU, yang rata-rata tidak melebihi ambang batas baku mutu untuk tambak udang dan biota laut, sedangkan kualitas tanah yaitu tekstur tanah (liat berpasir), pH tanah 4,8–6,8 dan bahan organik tanah 9–13% juga menunjukkan nilai yang tidak lebih dari ambang batas yang ditentukan. Kajian lainnya yaitu kondisi mangrove dengan kisaran indeks nilai penting 0–300 menunjukkan mangrove yang berperan dalam ekosistem tersebut dan dalam status mutu baik yang didukung dengan kerapatan 460 pohon/hektar. Oleh karena itu, nilai kerapatan yang tinggi dapat mendukung kegiatan pengembangan tambak udang yaitu dengan konsep ramah lingkungan (silvofisheries). Selain secara ekologi, secara sosial masyarakat juga mendukung pengembangan budidaya tambak udang (wawancara) dengan menyediakan (sewa) lahan dan tidak mengabaikan kerusakan lingkungan yaitu tetap mempertahankan mangrove. ABSTRACT This research discusses about conditions of habitats and mangrove ecosystems which become an important aspect to develop a good aquaculture in coastal areas. This study aims to analyze the condition of the habitat and mangrove ecosystem based on the quality of water, soil, vegetation of mangroves, and socio-economic conditions of the social community. The study was conducted in four villages in Simpang Pesak, East Belitung Regency from April to November 2013. The results showed the indicator for water quality such as salinity 28-30, temperature 27-36 oC, pH 7-7.5, visibility 50-70, TSS 11-85 mg/L and turbidity 0.91-46.00 NTU, are on average rate so it does not exceed the threshold quality standards for shrimp and marine life. Besides, the quality of the soil, which is indicated by the soil texture (sandy clay), soil pH 4.8-6.8 and soil organic matter 9-13% also showed that it was not exceed a specified threshold too. Advance studies represent mangrove condition with important value index range from 28.30-69.94 showed that mangrove hold an important role in these ecosystem and in good quality supported by the density of 460 trees/ha. Therefore, the value of high density can support the development of shrimp farming that have an environmentally friendly concepts (silvofisheries). Social community can also supports the development of aquaculture shrimp. Interview results showed community provides (lease) of land and try to preserve the mangrove condition to protect it from the environmental damage.