Environment And Penguin Ecology Evolution In Zolotov Island, East Antarctica In The Past 2000 Years

A 55cm long sediment core was collected from Zolotov Island, Vestfold Hills in East Antarctica. Elements concentration in the core was determined and its radiocarbon age was dated. Two different sections can be distinguished from this core by appearance judge and elements concentration: the upper 17cm section contains penguin bones and feathers, and bio-elements such as P,Mg,Cu,Zn,Cd and Ni have higher concentration in this section, indicating more influence from penguin activities. It can be determined by the radiocarbon dating that the time when penguins began to live in this island is between 1700aB.P～2000 aB.P. Q-mode factor analysis was employed to decide the changes of penguin droppings in the sediments, suggesting the historical dynamics of penguin populations, which has an overall increasing trend with three times of decline.By comparing the penguin population dynamics in Zolotov Island and Ardley Island in West Antarctica, it is found that they have very similar trend since 2000 aB.P, which both begin to increase fast from zero and have a decline in Little Ice Age. This fact indicates that penguin population dynamics in East Antarctica and West Antarctica have similar response to global climatic change.Big difference is found by analyzing data about land uplift and sea level fluctuation from different spots around Antarctica, and comparing the uplift rates in King George Island and Vestfold Hills, due to the difference of delectation process between Antarctic Peninsula and East Antarctica.The average uplift rate in Vestfold Hills since 6000aB.P is about 1.5 mm/a, which is calculated from the marine-lacustrine transition time and lake elevation. The height above sea level of sampling spots in Zolotov Islands are estimated about 4m when penguin landed this island, using the uplift rate 1.5mm/a.Using elements concentration of Ga and elements ratio such as Sr/Ca, Ca/K, we explored sedimentary environment changes and sediments resource in Zolotov Island and the application of elements ratio in studying sedimentary facies and sources, and tried to use the elements ratio of Ca/Fe in bedrock, penguin guano and sediments to recover the content of penguin droppings in sediments, which is in accord with that from Q-factor analyzing.By dicussing about the relationships among Antarcitc land uplift, penguin population and sedimentary environment, we find proper elevation is a prerequisite for penguin begin to land on islands, and lake sediments can be used to indicate land uplift and ecological evolution.