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Among the most powerful influences on the state of our freshwater systems include global climate and human interference. We can measure the impact both natural and anthropogenic changes have on freshwater by studying deep sediment cores from ancient lakes. Lake Fuxian, China is one of the few ancient lakes in the world and serves as an important source of drinking water in China. This lake lies along the edge of the Indo-Pacific Warm Pool, home to the formation of El Nino and La Nina events. These events are major drivers of global climate, influencing temperature fluctuations, precipitation patterns, and natural disasters around the world. Recently, industrialization and urbanization in the Yunnan Provence is thought to have influenced the state of Lake Fuxian, increasing anthropogenic influences on the lake. We hypothesized that: (1) this lake could record changes caused by anthropogenic inputs and global climate; and (2) local anthropogenic inputs had a greater impact on the state of the lake than global climatic changes. We have measured the elemental composition of a 30-cm sediment core from this lake through spectroscopy at 1cm intervals, recording approximately 300 years of data. Results to date show cycling in conservative metals through the core, representing switches in global El Nino and La Nina events. An increase in heavy metal concentrations reveal changes caused by anthropogenic influences. Our results provide insight to the difference in severity that both natural and anthropogenic may cause to a freshwater system. The elemental changes of the highest magnitude were caused by global climatic variation, revealing how natural global phenomena can have a greater impact on lakes than local anthropogenic inputs, an important observation for lake management as the threat of the state of freshwater resources is globally on the rise.