Background: Soil organic carbon stocks (SOCs) play a critical role in supporting soil quality and ecosystem functions. Information on SOCs content in coastal lands is scanty and the types of clay minerals and soil fraction size that affect SOCs are still debated. We evaluated the SOCs content and identified the mineral type and soil fraction affecting the SOCs on coastal land.&nbsp; 
 
Methods: Soil samples were collected from each layer of nine different soil profiles in three subdistricts: Seunuddon (SD), Lapang (LP) and Dewantara (DT) in Aceh Utara Regency of Indonesia. The soil profiles were taken from different distances (300, 900 and 1500 m from the shoreline-d.f.s).&nbsp;&nbsp; 
 
Result: The results revealed that SOCs possessed by each soil layer of coastal land in Aceh Utara varied between 0.64 to 43.45 MgC ha-1. The highest to lowest average total of SOCs content for the location is SD&gt;DT&gt;LP, while for the position, the distance to the shoreline is 900 m&gt;1500 m&gt;300 m. Clay minerals such as labradorite, smectite, vermiculite and chlorite positively increase the SOCs content. Very fine sand is a size of the soil fraction that affects the increase in the levels of SOCs in coastal land.

Soil Fractions Affect on Soil Organic Carbon Stock in the Coastal Land of Aceh Utara Regency, Indonesia

Background: Diesel power plants (DPP) are crucial for energy production but can significantly impact the environment through the release of heavy metals such as copper (Cu), iron (Fe) and zinc (Zn). Pollutants originating from diesel combustion, lubricating oils and waste disposal often accumulate in sediments and aquatic ecosystems, posing risks to environmental health. 
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Methods: This study aims to evaluate the concentration and distribution of heavy metals, namely copper (Cu), iron (Fe) and zinc (Zn), in sediments around the suppa diesel power plant located in Pinrang Regency, South Sulawesi. The analytical methods used include the geoaccumulation index (Igeo), pollution load index (PLI), ecological risk index (ERI) and co-kriging spatial analysis. 
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Result: The results indicate that the measured concentrations of heavy metals, with Cu reaching 45 mg/kg, Fe 1,200 mg/kg and Zn 30 mg/kg, show significant variation among sampling locations. The findings reveal that the sediments in the area are generally uncontaminated; however, moderate contamination is observed at Station 1, indicating localized pollution, particularly near the shoreline and around the plant, highlighting the need for ongoing monitoring. The limitations of this study include a limited number of samples and a short sampling period, which may not fully reflect seasonal fluctuations in heavy metal concentrations. This research provides valuable insights for policymakers and stakeholders in formulating more effective and sustainable waste management strategies, as well as contributing to a deeper understanding of the environmental challenges posed by DPP operations, emphasizing the importance of continuous monitoring. 
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Assessment of the Influence of Wastewater from Diesel Power Plant Through the Accumulation Level and Distribution of Heavy Metals Cu, Fe and Zn in Marine Sediments in the Waters of Suppa, South Sulawesi