Human activity has removed more than one-tenth of trees and plants from the Amazon rainforest since the 1960s, a study shows. Widespread removal of trees has contributed to a rise in the amount of carbon dioxide in the atmosphere, increasing the potential impact of climate change, researchers say.

Humans have breached this cycle by digging up fossil fuels and burning them, leading to carbon dioxide building up in the atmosphere faster than natural systems can soak it up. This has led to a net increase in greenhouse gases in the atmosphere, causing the planet to heat up.

Human activities have mobilized Earth elements and accelerated their cycles – for example, more than doubling the amount of reactive nitrogen that has been added to the biosphere since pre-industrial times. Global carbon dioxide emissions are the most significant driver of human-caused climate change.

The carbon cycle is a process where carbon dioxide travels from the atmosphere into living organisms and the Earth, then back into the atmosphere. Plants take carbon dioxide from the air along with water and photosynthesis from the sun and use it to make food.

Carbon cycle explains the movement of carbon between the earth’s biosphere, geosphere, hydrosphere and atmosphere. Carbon atoms are then released as carbon dioxide when organisms respire. The formation of fossil fuels and sedimentary rocks contribute to the carbon cycle for very long periods.

Processes in the carbon cycle

Stage one: Carbon enters the atmosphere by – respiration in organisms (e.g. animals breathing) – combustion (e.g. burning of fossil fuels/ wood) – decomposition and decay (microorganisms respiration) Stage two: Carbon Dioxide is absorbed by producers in photosynthesis.

In the natural carbon cycle, there are two main processes which occur: photosynthesis and metabolism. During photosynthesis, plants use carbon dioxide and produce oxygen.

So, the formation of fossil fuels is the phenomena which takes the longest time in the carbon cycle.