Biogeochemical Cycles

Key Questions

  • Answer:

    because matter on earth is limited in amount, and space for dead bodies as well.


    If dead bodies accumulate on earth, then there will b no space to keep all of them. This is one reason why recycling their bodies is important.
    Another point is that mater is found on earth and has been there since earth was developed and became ready to support life. After that matter has not been added to earth in big amount, nor in a regular manner, so it must be recycled to support the new organisms which are continuously being added to the ecosystem.

  • Answer:

    Deforestation affects biogeochemical cycling mainly by disrupting the water cycle, causing water to be lost more rapidly from the ecosystem and with it important elements and nutrients.


    The biggest effect deforestation has on the biogeochemical cycles of a given area occurs via the disruption of the water cycle. Streams and rivers carry water away from the landscape and to the sea. Trees and other plants retain water by sucking it up from the ground and returning it to the atmosphere above through a process known as evapotranspiration.

    Because water is an excellent solvent, elements like nitrogen and phosphorus and ions like calcium are all easily transported by water. When deforestation occurs water is no longer captured by the trees and all of the important ions and molecules are exported from the system by streams and rivers.

    Some of the consequences include a loss of base cations from the soil, making them acidic - a harsh environment for biota. The loss of ammonium, nitrate and phosphate - important nutrients for growth - can lead to oligotrophic conditions. Increased water flow through the soil leads to erosion, which can remove organic materials that serve as food to soil organisms. Of course, without trees there is a loss of habitat and food resources needed by organisms that themselves influence biogeochemical cycling through their activities.

    An excellent way to learn more about this particular topic is to review the research done at Hubbard Brook Experimental Forest in New Hampshire ( They were the first to quantify the changes due to deforestation.

  • Biogeochemical cycles are found everywhere around us.

    Many biogeochemical cycles affect our daily lives in many ways. A prime example of one of these cycles is the water cycle. The constant changing states of water and how it interacts with our environment ( both gas, ice, and liquid states). Some key words with the water cycle include condensation, precipitation, and evaporation.

    Water Cycle

    Another great example in our everyday lives is the flow of oxygen and carbon dioxide. The constant respiration from animals and photosynthesis from plants creates a constant cycle which has been continuing for millions of years.

    Oxygen Cycle

    Other cycles include the nitrogen cycle, phosphorus cycle, and sulfur cycle. Even today scientists are beginning to discover new cycles such as weather patterns, and human impact on the environment, which can drastically change the speed, intensity, and balance of these relatively unknown cycles.