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δ15N values of chlorophylls and porphyrin derivatives from Touirist Formation sample 13-Ni (pink stars), the water column and sediments of various modern water bodies, and Phanerozoic sediments. Lakes, freshwater lakes (compiled from refs. 37, 48, 52, and 75). BPhe, bacteriopheophytin; Phe, pheophytin; PPhe, pyropheophytin.
