This diploma thesis fundamentally examines changes in the environment which are caused by human beings.In the first chapter the development, the shape and the structure as well as the system of the Earth are described. In addition to that, the climate as a subsystem composed of the atmosphere, the hydrosphere; the lithosphere and the biosphere is investigated into further.In the following section, the thesis provides an overview of the history of the Earth. This chapter should particularly highlight that compared to the age of the Earth, mankind has occupied the planet for a very short time only. Furthermore, the geological time scale, the anthropocene, the stratigraphy as well as the radiometric dating are introduced.Based on the fact that a fundamental change in the climatic system can be observed, the four spheres mentioned above represent the basis of the chapter dealing with anthropogenic environmental changes. Hence, the impact of human beings on each of the four spheres are analysed respectively. So far, research has shown that mankind has already influenced each sphere which results in drastic environmental changes. The alterations originate from the usage of renewable and non- renewable resources, the production of refuse, the use of chemicals and the modification of natural surfaces.In order to complete the thesis, the ecological footprint will be introduced in the last chapter. The ecological footprint represents a scientific method to calculate humans demand for natural capital. The measurements of the global ecological footprint demonstrate that the natural resources of the Earth are already used beyond their capacities. This means that annually, more resources are consumed than Earth can regenerate and refuse produced than the Earth is able to assimilate. Currently, 1.5 planet Earths would be necessary to preserve humans quality of life sustainably. This result is alarming and should encourage people to reassess how they treat our environment.