Marine debris problems is an environmental problem that happens in Ambon Bay. Almost every day marine debris is seen floating and spreading along coastal waters of Ambon City. The marine debris in Ambon Bay is generally from mainland rubbish, which is intentionally discharge to beach or river body, and eventually will be carried by river inflow to coastal area, so the tides and current waters forcing the marine debris flowed to middle of coastal waters. Pattern of marine debris transport basically is influenced by the waters circulation pattern in Ambon Bay. The research purpose is to knowing density and study the transport pattern of floating marine debris (FMD) in west coast waters of Inner Ambon Bay (IAB). Using line transect method to analyze the FMD density and the trajectory method to determine transport pattern of FMD. Research result show that Hative 1 is the area with highest density of FMD and dominant type of FMD in west coast waters IAB is plastic type category as 93.

The presence of cohesive sediment in the water column can reduce light penetration and affect photosynthesis process, and it can be disrupted the primary productivity of aquatic, and sedimentation of coastal waters. The objective of this research was to determine the cohesive sediment distribution pattern and the relationship with sedimentation. MIKE 3 FM modeling was used to understand the process of sediment transport and sedimentation on Inner Ambon Bay. Sediment transport modeling method was divided into two stages: the hydrodynamic modeling (baroclinic) and sediment transport (mud transport) modeling. The model results indicate current patterns in the Inner Ambon Bay is influenced by the tidal factor. Suspended sediment dispersed vertically from the surface to a depth of 30 m with concentration of about 3.5-15 Kg/m3. The maximum consentration of the suspended sediment occurs at head of the bay (around Waiheru, Passo, and Lateri). Model simulations for 30 days showed the rate of erosion is about 1.04-6.15 Kg/m2/s, while in Inner Ambon Bay the erosion about 9.07x10-8Kg/m2/s only occurred in T1 station. Sedimentation associated with the cohesive sediment accumulation and it was shown by bed level. In addition, the simulation showed bed level in sill ranged at 0.01-0.19 cm and 0.47 mm/day on average, while in the Inner Ambon Bay it ranged from 1.75-10.01 cm, and the sedimentation rate was approximately 39.9 mm/day.

ABSTRAKAdanya sedimen kohesif di perairan dapat mengurangi penetrasi cahaya ke dalam air dan fotosintesis sehingga produktifitas primer perairan dapat terganggu. Pengendapan sedimen kohesif di perairan pesisir dapat mengakibatkan sedimentasi. Tujuan peneltian ini menunjukkan pola sebaran sedimen kohesif dan hubungannya dengan sedimentasi yang terjadi di Teluk Ambon Dalam (TAD). Pemodelan menggunakan MIKE 3 FM untuk menginterpretasikan proses sedimentasi pada TAD. Pengerjaan pemodelan dibagi menjadi 2 tahap yaitu pemodelan hidrodinamika (baroclinic) dan transport sedimen (sedimen transport). Hasil model menunjukkan bahwa pola pergerakan arus yang terjadi pada perairan TAD dipengaruhi oleh faktor pasang surut. Pola penyebaran sedimen kohesif secara vertikal mulai dari permukaan sampai dengan kedalaman 30m sekitar 3,5-15 Kg/m 3 . Konsentrasi sedimen kohesif tertinggi terjadi pada pangkal teluk (di sekitar Waiheru, Passo, dan Lateri). Hasil simulasi model selama 30 hari menunjukan bahwa tingkat erosi pada ambang (sill) berkisar antara 1,04-6,15 Kg/m 2 /s, sedangkan pada TAD hanya terjadi pada stasiun T1 yaitu 9,07x10 -8 Kg/m 2 /s. Sedimentasi yang berhubungan akumulasi sedimen kohesif ditunjukan oleh ketebalan lapisan (bed level). Ketebalan lapisan sedimen pada area ambang yaitu 0,01-0,19 cm atau rata-rata 0,47 mm/hari, sedangkan pada TAD berkisar antara 1,75-10,01 cm, atau dengan nilai rata-rata sekitar 39,9 mm/hari.

Plastic pollution in the marine environment is a global problem, which is currently in particular concern because this pollutant can be a negative impact on ecosystems. Identification of group plastic can be a solution to plastic debris management strategy throughout Outer Ambon Bay (OAB). The purpose of this study was to determine and analyze the composition and percentage of plastic debris in OAB and analyze the density of plastic debris in OAB according to the plastic group. The research findings from 20 sampling sites showed that the plastic debris category found was mostly plastic packaging, 86% on the coast of the Jasirah Leitimur and 78% on the Jasirah Leihitu. The highest density of plastic waste was found at Tantui and Mardika shores located in Jasirah Leitimur. The sampling site in Jasirah Leihitu shows that Rumahtiga and Liliboy have the highest density of plastic. Overall, the dominant group of plastic found on the shores of Outer Ambon Bay is plastic packaging.

Abstract; Generally in Inner Ambon Bay (IAB) the sedimentation problem generate revamp of waters base configuration that influence IAB circulation process. We use model tool of MIKE 3 FM in this research to modeling three-dimensional hydrodynamics of process circulation and modeling of particle tracking. The purposes of the research are to analysis pattern of water mass circulation which is considering the baroclinic mode, to estimate the movement and pattern of cohesive sediment from every river inflow and to estimate the flushing as well as residence time of IAB. Simulation result of models is to represent circulation and particle movement in rainy season and dry season in IAB. In baroclinic mode the vertical eddy dominant happen in middle of IAB and in front of Poka-Galala sill. This vertical eddy is influenced by topography configuration and stratification water mass due to the rivers inflow. In model simulation of particle tracking the pattern of particle movement is dominant in middle of bay and along coastal of Lateri and Halong. The average of residence time and flushing time are 5 days and 9 days in rainy season, respectively while those in dry season are 2 days and 5 days respectively.