Electronic Theses and Dissertation

Pencemaran logam berat timbal (Pb²⁺) di perairan menjadi ancaman serius terhadap kelangsungan hidup dan kesehatan ikan budidaya, termasuk ikan bandeng (Chanos chanos). Penelitian ini bertujuan untuk mengevaluasi efektivitas makroalga Caulerpa taxifolia sebagai agen fitoremediasi dalam menurunkan kadar Pb²⁺ di perairan serta dampaknya terhadap kelangsungan hidup dan histopatologi hati ikan bandeng. Penelitian dilakukan selama 14 hari dengan lima perlakuan yaitu: P0 (kontrol tanpa alga), P1 (25 g), P2 (50 g), P3 (75 g), dan P4 (100 g) Caulerpa taxifolia yang dipelihara bersama ikan bandeng dalam media tercemar Pb²⁺ dosis kronis (5,33 mg/L). Hasil penelitian menunjukkan bahwa peningkatan biomassa Caulerpa taxifolia mampu menurunkan kadar Pb²⁺ dalam air secara signifikan dan meningkatkan tingkat kelangsungan hidup ikan bandeng. Selain itu, tingkat kerusakan jaringan hati seperti nekrosis, degenerasi hidropik, dan degenerasi lemak menunjukkan penurunan seiring bertambahnya dosis Caulerpa taxifolia. Perlakuan P4 memberikan hasil terbaik dengan kelangsungan hidup 90% dan kerusakan histopatologis paling ringan. Penelitian ini menyimpulkan bahwa Caulerpa taxifolia efektif sebagai agen fitoremediasi alami dalam perairan tercemar logam berat Pb²⁺ dan berpotensi diterapkan dalam sistem budidaya berkelanjutan.

Kata Kunci: C. taxifolia, fitoremediasi, timbal (Pb²⁺), ikan bandeng (Chanos chanos), histopatologi hati, kelangsungan hidup.

Heavy metal pollution, particularly lead (Pb²⁺), poses a significant threat to the survival and health of cultured fish, including milkfish (Chanos chanos). This study aimed to evaluate the effectiveness of the macroalga Caulerpa taxifolia as a phytoremediator in reducing Pb²⁺ concentrations in water and its impact on the survival rate and liver histopathology of milkfish. The experiment was conducted for 14 days using five treatments: P0 (control without algae), P1 (25 g), P2 (50 g), P3 (75 g), and P4 (100 g) of C. taxifolia co-cultured with milkfish in water contaminated with chronic Pb²⁺ exposure (5.33 mg/L). Results showed that increasing the biomass of C. taxifolia significantly reduced Pb²⁺ concentrations in the water and improved the survival rate of the fish. Additionally, liver tissue damage, such as necrosis, hydropic degeneration, and fatty degeneration, decreased with higher algae dosages. Treatment P4 showed the best outcome with a 90% survival rate and the mildest histopathological damage. This study concludes that C. taxifolia is effective as a natural phytoremediation agent in Pb²⁺-contaminated waters and holds potential for application in sustainable aquaculture systems. Keywords: Caulerpa taxifolia, phytoremediation, lead (Pb²⁺), milkfish (Chanos chanos), liver histopathology, survival rate.