Stable isotope, Seabird, Guano, Lagoon, Bioenrichment, Trace metals, Nature, Environmental Monitoring, Trace Elements - analysis, Animals, Feces - chemistry, Charadriiformes, Conservation of Natural Resources, Water Pollutants, Chemical - analysis, Gulls, Natural areas
Nitrogen Isotopes - analysis, Trace Elements - metabolism, Environmental Monitoring, Fishes - metabolism, Trace Elements - analysis, Feathers - chemistry, Invertebrates - metabolism, Carbon Isotopes - analysis, Water Pollutants, Chemical - analysis, Food Chain, Sicily, Water Pollutants, Chemical - metabolism, Animals, Poaceae - chemistry, Geologic Sediments...