The United States is home to less than 5% of the world’s people, yet it produces 25% of the CO2 emissions on the planet. Human activity has greatly increased the quantity of nitrogen cycling through the biosphere, changed land use across the globe, and increased the atmospheric concentration of CO2 . Changes such as these threaten the diversity of life on earth and may endanger our very life-support systems.
Today, most of earth’s human population lives in cities and most of us have little direct contact with nature. More than ever before, though, the future of our species depends on how well we understand the relationships between organisms and the environment. In the process we then can examine the impact these organisms have on their environment or their “ecological footprint.”
There are a number of factors which directly effect the “human footprint.” Human activities since 1750 have played a significant roll by overloading the atmosphere with carbon dioxide, thus retaining solar heat that would otherwise radiate away. This retained heat translates into the much discussed “climate change” that our planet is experiencing at an alarming rate. As the earth’s climate changes it will cause a reduction in biodiversity, changes in seasons, rainfall patterns, ocean currents, and other parts of the earth’s life-support systems.
Our footprint is also strongly felt on the destruction and fragmentation of habitats as humans occupy, consume and control more of the planet. All the ecosystems are under severe stress from human intrusion as well as land and waterborne pollution.
Modern agriculture also heavily contributes to our environmental footprint by promoting a massive decline in biodiversity. People have historically used over 7,000 plant species for food, now they are reduced to largely 20 species around the world. This same sort of reduction in genetic variability has taken place in the herds of cattle, sheep, and horses that humans raise.
In addition to the destruction and exploitation of habitats and the impact of agriculture, a variety of related human actions have further increased the measure of our footprint. These include over fishing, commercial hunting and poaching, predator and pest control, the sale of exotic pets and plants, and deliberate or accidental introduction of alien or non-native species into ecosystems.
With this in mind, the goal of every human being should be to work on ways to change or modify our lifestyle so as to consciously strive to have only a “small footprint” on the face of our planet.