Early Cretaceous terrestrial ecosystems in East Asia based on food-web and energy-flow models

摘要: In recent years, there has been global interest in the environments and ecosystems around world. It is helpful to reconstruct past help understand them present future. The are an evolving continuum with those of This paper demonstrates contribution geology paleontology such continua. Using fossils, we can make estimation population density as ecosystem index based on food-web energy-flow models. Late Mesozoic nonmarine deposits distributed widely eastern Asian continent containvarious kinds fossils fishes, amphibians, reptiles, dinosaurs, mammals, bivalves, gastropods, insects, ostracodes, conchostracans, terrestrial plants, others. These fossil organisms useful for late reconstruction using We chose Early Cretaceousfluvio-lacustrine basins Choyr area, southeastern Mongolia, Tetori Japan, these analyses a potential model other similarbasins inEast Asia.The models arerestored ontaxa that occurred inthese basins. Theyform fourorfivetrophic levelsinan energy pyramid consisting rich primary producers at its base smaller biotas higher food web. general atypicalecosystem.Concerningthepopulationdensitiesofvertebratetaxa in1 km 2 inthesebasins,somedifferencesarerecognizedbetweenEarly Cretaceousand present.For example,Cretaceousestimates suggest 2.3 to4.8 times asmany herbivores 26.0 to105.5 carnivore population. differences evaluation densities vertebrate taxa. Such may also be caused by differentmetabolismofdifferenttaxa.Preservationmayalsobeafactor,andwerecognizethatvariousproblemsoccurinpastecosystemreconstructions.