Orem, W. H., Burnett, W. C., Landing, W. M., Lyons, W. B., & Showers, W. (1991). Jellyfish Lake, Palau: Early diagenesis of organic matter in sediments of an anoxic marine lake. Limnology and oceanography, 36(3), 526-543.
Jellyfish Lake on Eil Malk Island in the Western Pacific country of Palau is an isolated marine lake. Restricted circulation in the lake leads to formation of anoxic bottom water layer which helps preserve organic matter in sediments. The authors sought to measure the elementary contents and stable isotopes in sediments from Jellyfish Lake and studied the process of diagenesis.
Wet sediment samples were collected from Jellyfish Lake for dissolved organic carbon analysis. Then the concentrations of elemental contents in organic matter obtained were measured. Carbonate shells of bivalves and gastropods from Jellyfish Lake sediments were collects for stable isotopes measurements.
The result of measurement shown that organic matter is abundant in sediments of Jellyfish Lake. Around 91% of organic matters in sediments are derived from vascular plant remains and 9% are from algal. Elementary content results and stable isotopic data of shells from the sediments suggest the differences between Jellyfish Lake and other marine lakes can caused by long-term geological changes, close climatic and ecological changes, vegetation around the lake.
Significance for Palau:
This research is relevant to conservation of jellyfish and other species in Palau because it studied the formation and composition of organic matters in Jellyfish Lake, a marine lake which sufficiently isolated. Permanently stratified marine lake like Jellyfish Lake is not usual. The stratification caused by restricted water circulation separate lake water into oxygenated top layer and highly sulfidic anoxic bottom layer. Special conditions of this lake affects speciation and migration of the golden jellyfish, Mastigias cf. papua etpisoni and other species. Findings about the elementary content composition an organic matters in Jellyfish Lake helps maintain and protect the habitat for living species in Jellyfish Lake.