Laju Dekomposisi Serasah Daun Avicennia marina pada Berbagai Tingkat Salinitas

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ABSTRAK

ELISA JANUARITA DOLOKSARIBU_{. Laju Dekomposisi Serasah Daun}

Avicennia marina_{pada Berbagai Tingkat Salinitas. Dibimbing oleh}YUNASFI dan ZULHAM APANDY HARAHAP

Serasah mangrove yang mengalami dekomposisi memberikan sumbangan bahan organik yang merupakan sumber pakan bagi berbagai jenis ikan dan organisme lain di ekosistem mangrove. Penelitian ini bertujuan untuk menentukan pengaruh tingkat salinitas terhadap laju dekomposisi serasah dan mengetahui kandungan unsur hara karbon (C), nitrogen (N) dan fosfor (P) pada serasah daun mangrove A. marina _{yang dilepas selama proses dekomposisi. Penelitian}

dilakukan di Paluh Kurau Kecamatan Hamparan Perak Kabupten Deli Serdang Provinsi Sumatera Utara dilaksanakan pada bulan Februari hingga Mei 2017. Hasil penelitian serasah daun A. marina pada tingkat salinitas 0-10 ppt lebih cepat terdekomposisi. Rata-rata bobot sisa serasah daun A. marina _yang

mengalami dekomposisi pada tingkat salinitas 0-10 ppt, 10-20 ppt dan 20-30 ppt yaitu 1,46 gram, 5,86 gram, dan 6,53 gram. Laju dekomposisi serasah daun A. marina _{pada tingkat salinitas 0-10 ppt, 10-20 ppt dan 20-30 ppt yaitu 0,54, 0,49,}

dan 0,48. Kadar unsur hara C serasah daun A. marina _{pada tingkat salinitas 0-10}

ppt, 10-20 ppt dan 20-30 ppt yaitu 18,61%, 18,97%, dan 12,41%. Kadar unsur hara N serasah daun A. marina pada tingkat salinitas 0-10 ppt, 10-20 ppt dan 20-30 ppt yaitu 1,51%, 1,68%, dan 1,68% serta Kadar unsur hara P serasah daun A. marina _{pada tingkat salinitas 0-10 ppt, 10-20 ppt dan 20-30 ppt yaitu 0,58%,}

0,52%, dan 0,51%.

Kata Kunci : Serasah Mangrove, A. marina_{, salinitas, laju dekomposisi, unsur}

hara

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ABSTRACT

ELISA JANUARITA DOLOKSARIBU_{. The Rate of decomposition} Avicennia marina _{Litter Leaf at Various Levels of Salinity. Under Academic Supervision by}

YUNASFI_andZULHAM APANDY HARAHAP

The mangrove litter which has been decomposed contributes organic matter as food source for many species of fish and other organisms in the mangrove ecosystem. This study aims to determine the effect of salinity on the rate of leaf litter decomposition A. marina _{and to know the nutrient content of}

carbon (C), nitrogen (N) and phosphorus (P) in the A. marina _{litter leaf which}

been released during the decomposition time. This research was done at Hamparan Perak base Deli Serdang sub-district of North Sumatera Province during February until Mei 2017. The results of the study of leaf litter A. marina _at

0-10 ppt salinity level more quickly decomposes. The average weight of the rest of the leaf litter A. marina which decompose at a rate of 0-10 ppt salinity, 10-20 ppt and 20-30 ppt yaitu 1,46 grams, 5,86 grams, dan 6,53 grams.The rate of leaf litter decomposition A. marina _{at a rate of 0-10 ppt salinity, 10-20 ppt and 20-30}

ppt was 0,54, 0,49, dan 0,48. Carbon levels of nutrients in the leaf litter A. marina

ppt salinity level 0-10, 10-20 ppt and 20-30 ppt was 18,61%, 18,97%, dan 12,41%. Levels of nutrients nitrogen in leaf litter A. marina _{ppt salinity level}

0-10 ppt, 0-10-20 ppt and 20-30 ppt was 1,51%, 1,68%, dan 1,68% . As well as the levels of the nutrient phosphorus leaf litter A. marina on ppt salinity level 0-10 ppt, 10-20 ppt and 20-30 ppt was 0,58%, 0,52%, dan 0,51% respectively.

Keywords : mangrove litter, A. marina_{, salinity, rate of decomposition, nutrients}