Pengaruh Tingkat Kedalaman dan Lama Penggenangan terhadap Pertumbuhan Bibit Api-Api Putih (Avicennia marina)

Abstract

Api-api putih (Avicennia marina) merupakan mangrove mayor sekaligus spesies pionir yang tumbuh pada zona terdepan dan dipengaruhi pasang surut, sehingga penting diteliti responsnya terhadap lama dan kedalaman penggenangan sebagai dampak kenaikan muka air laut. Penelitian ini menggunakan rancangan faktorial 2×2 dalam Rancangan Acak Lengkap (RAL) dengan dua faktor, yaitu lama penggenangan (4-5 jam dan 7-8 jam) serta kedalaman penggenangan (sedalam leher akar dan ¼–½ tinggi bibit), menghasilkan empat kombinasi perlakuan. Hasil penelitian menunjukkan bahwa perlakuan yang diberikan selama pengamatan (tingkat kedalaman dan lama penggenangan) tidak memberikan pengaruh terhadap pertumbuhan bibit A. marina. Ada kecenderungan perlakuan A1B1 memberikan hasil yang cukup baik terhadap tinggi (95,8 cm), biomassa (BBT 187,28 g dan BKT 68,16 g), serta jumlah daun (79 helai), A2B2 pada diameter batang (10,82 mm), A1B2 pada Indeks Mutu Bibit (9,62), dan A2B1 pada Nisbah Pucuk Akar (3,35). Secara keseluruhan, bibit A. marina menunjukkan kemampuan adaptasi yang cukup baik terhadap berbagai kondisi genangan yang diberikan.

White mangrove (Avicennia marina) is a major mangrove and pioneer species that grows in the seaward zone and is directly influenced by tidal inundation. Therefore, understanding its response to different inundation durations and depths is important, especially in relation to sea-level rise. This study used a 2 × 2 factorial experiment in a Completely Randomized Design (CRD) with two factors: inundation duration (4–5 hours and 7–8 hours) and inundation depth (root collar level and ¼–½ of seedling height), resulting in four treatment combinations. The results showed that the applied treatments (inundation depth and duration) did not significantly affect the growth of A. marina seedlings during the observation period. However, there was a tendency for treatment A1B1 to produce relatively better performance in seedling height (95.8 cm), biomass (total fresh weight of 187.28 g and total dry weight of 68.16 g), and leaf number (79 leaves). Treatment A2B2 tended to result in the largest stem diameter (10.82 mm), A1B2 produced the highest Seedling Quality Index (9.62), and A2B1 showed the highest Shoot-to-Root Ratio (3.35). Overall, A. marina seedlings demonstrated a relatively strong adaptive capacity to the various inundation conditions applied in this study.