Zona intertidal memiliki keragaman spesies organisme laut yang cukup tinggi termasuk spesies gastropoda laut. Sebagian besar spesies gastropoda laut ini dikonsumsi oleh masyarakat khususnya masyarakat yang hidup pada daerah pesisir di Provinsi Maluku. Penelitian tentang keragaman spesies gastropoda khususnya di Pulau Ambon masih sangat terbatas dan belum banyak dipublikasi. Penelitian ini bertujuan untuk menentukan komposisi spesies, densitas ekologi, indeks similaritas, indeks keragaman spesies, indeks keserasian dan indeks dominansi spesies gastropoda. Penelitian dilakukan di zona intertidal Pulau Ambon pada lima lokasi sampling. Sampling dilakukan pada bulan Desember-Februari 2022 pada saat air surut di siang hari. Pengambilan sampel gastropoda menggunakan metode transek garis. Ada sekitar 78 spesies gastropoda laut ditemukan dalam penelitian ini.  Jumlah spesies dan densitas ekologi bervariasi berdasarkan lokasi sampling. Indeks similaritas dari komunitas gastropoda yang ditemukan dalam penelitian ini bervariasi antara 3,62% dan 34,12%. Indeks keragaman spesies (H`) bervariasi antara H’ = 2,52 dan H` = 2,995. Indeks keseragaman (evenness index-J`) berkisar antara J` = 0,74 dan J` = 0,82. Indeks dominansi Simpson (D) berkisar antara D = 0,09 dan D = 0,14. Ada sekitar 9-17 spesies gastropoda kategori jarang yang ditemukan pada areal penelitian ini memberikan sumbangan terhadap keragaman spesies dari komunitas gastropoda yang ditemukan. Sebaliknya ada sebanyak 5-10 spesies kategori umum yang memberikan sumbangan terhadap dominansi spesies gastropoda.

Mangroves can store carbon. However, it also produces carbon emissions by degrading organic matter in mangrove sediments. This research was conducted in a mangrove ecosystem at Waiheru, in the inner Ambon bay, to determine CO2 and CH4 emissions and their potential for global warming (GWP) from mangrove sediments. Gas is taken through a syringe mounted on the hood. Gas concentration analysis used the gas chromatography method, while the average gas concentration in each sediment was tested using ANOVA Single Factor. The results showed that the average concentration of CO2 gas was significantly different for each sediment (P-value <0.05), while the average concentration of CH4 gas was not significantly different (P-value >0.05). The largest CO2 gas emission in mangrove sediments in Waiheru Village was found in sandy mud sediments with an emission value of 136.99 mg.m−2.h−1, and the lowest was in sand sediments, namely 13.01 mg.m−2.h−1. Meanwhile, the largest emission of CH4 gas was in silty sand sediments, namely 0.32 mg.m−2.h−1, and the lowest was in sandy mud sediments, namely 0.15 mg.m−2.h−1. Fluctuations in carbon gas emissions in each sediment are inversely proportional, which indicates that the formation of CH4 gas is obtained through ethanol reduction, which utilizes CO2 gas concentrations. The total GWP in the mangrove sediments of Waiheru Village is 231.58 mg.m−2.h−1. The GWP contributed by the type of sandy silt sediment was 140.72 CO2-eq mg.m−2.h−1, muddy sand was 70.95 mg.m−2.h−1, and sand sediment was 19.91 CO2-eq mg.m−2. h−1.

Strombus luhuanus (strawberry conch), Linneaus 1758 is a marine mesogastropod belongs to Strombidae family. S. luhuanus is locally consumed by coastal communities in Maluku province to fulfill their protein needed, which will decreasing the stock in natural environment. The biological study including population dynamics needed to maintain S. luhuanus population. The research was conducted in Oma coastal water, Central Maluku, Eastern Indonesia during January to December 2019. The objectives of this research were to study the aspect of population dynamics of S. luhuanus such as asymptotic length (L∞), growth coeficient (K), natural mortality (Z), exploitation rate (E) and recruitment. A total of 1823 individual of S. luhuanus found in this study which consisted of 831 individual of males and 992 individual of females population. Shell size of S. luhuanus varied monthly. The result showed that in general, the male population showed five cohort, while the female showed six cohort. L∞ = 63.40 mm, K = 0.65 for females population; whilst for the males population, L∞ = 69.80 and K = 0.5. Total mortality (Z) for both population were Z = 3.03 and Z = 4.32, respectively. Exploitation rate of S. luhuanus in this study area showed that the population was overexploited (E = 0.64 and E = 0.79 for females and males population, respectively).

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Strombus luhuanus is a marine mesogastropod known as strawberry conch belongs to the Strombidae family. This species is consumed by the coastal community in Maluku province and collected by people at various shell size. The objective of this research was to determine the temporal size distribution and the size difference between its sexes. Sampling was conducted in Oma coastal water, Central Maluku, Eastern Indonesia. A specimen of S. luhuanus collected randomly during low tide from April to July 2018. Some characters of S. luhuanus were measured including shell length, shell width, spire height, and lip thickness. The result of this research showed that shell length of this species varied between 30.81 mm and 55.20 mm; the shell width varied from 16.33 mm to 32.25 mm; its spire height varied between 5.00 mm and 15.20 mm, while the lip thickness varied from 0.10 mm to 5.54 mm. The average of shell length, shell width and spire height of S. luhuanus were high in June sampling period compared to another sampling periods, whereas lip thickness of this species was high in July sampling. Based on its sex, the shell size parameters measured in our study were higher in female specimen than the male one. The size groups of this gastropods were dominated by 38.79-47.39 mm in shell length. Lip thickness of the shell showed that S. luhuanus was in developing stage of growth in this study and S. luhuanus showed sexual dimorphism.