top of page

Biogeochemical Cycle| Explained

Updated: Feb 7

CREDIT : WIKIPEDIA

The words "bio" and "geo," which refer to the components of the geology, and "chemical," which denotes the elements that go through cycles, are the origins of the phrase biogeochemical.

Atoms are the form in which matter on Earth is present and conserved. Because matter cannot be generated or destroyed, it is recycled in a variety of ways throughout the earth's system.


The sun provides energy to the earth, which is reflected back to it as heat; the remaining elements are part of a closed system. The principal components consist of:

  • Hydrogen Carbon

  • Nitrogen

  • Air

  • Phosphorus Sulfur

The biotic and abiotic elements of the ecosystem recycle these elements. The abiotic elements of the ecosystem are the lithosphere, hydrosphere, and atmosphere.


Biogeochemical Cycle Types

Essentially, there are two categories of biogeochemical cycles:


Gaseous cycles: These comprise the water cycle, oxygen, nitrogen, and carbon cycles.

Sedimentary cycles: These include the cycles of rock, phosphorus, and sulfur.

Let's quickly review each of these biogeochemical cycles:


Cycle of Water

The water from the various bodies of water cools, condenses, evaporates, and then returns to the ground as rain.


The weather patterns are sustained by this biogeochemical cycle. The atmosphere's pressure and temperature are altered by the interactions between the water and its surroundings.


This process is aided by another process known as evapotranspiration, or the production of vapour from leaves. It is the process by which water evaporates from vegetation, soil, and bodies of water and returns to the sky to condense and fall as rain.


Cycle of Carbon

The exchange of carbon between the biosphere, geosphere, hydrosphere, atmosphere, and pedosphere occurs in one of the biogeochemical cycles.


For photosynthesis, all green plants require carbon dioxide and sunlight. Thus, the plant stores carbon. When dead, the green plants are buried in the soil, which releases carbon to create fossil fuels. Carbon dioxide is released into the atmosphere during the burning of these fossil fuels.


Furthermore, the carbon contained in plants is obtained by the animals who eat them. After these animals die, their decomposition releases this carbon back into the atmosphere. Animal respiration results in the return of carbon to the environment.


Massive amounts of carbon dioxide are created, which are then stored as fossil fuels (coal and oil) and can be exploited for a variety of industrial and non-commercial uses. When these fuels are used in factories, carbon is released back into the environment.


Cycle of Nitrogen

Nitrogen is transformed into multiple forms and circulates through the atmosphere and different ecosystems, including terrestrial and marine ecosystems, during the biogeochemical cycle.


Life requires nitrogen as a necessary component. The nitrogen-fixing bacteria found in the root nodules of leguminous plants fix atmospheric nitrogen and release it into the soil for use by plants and soil organisms.


This nitrogen gas is changed by the bacteria found in plant roots into ammonia, a substance that can be used. Additionally, fertilizers provide plants with ammonia. Nitrites and nitrates are produced from this ammonia. The nitrates are converted into nitrogen by the denitrifying bacteria and released back into the atmosphere.


Cycle of Oxygen

The lithosphere, the biosphere, and the atmosphere are all touched by this biogeochemical cycle. On Earth, oxygen is a plentiful element. Up to 21% of it is present in the atmosphere in its elemental form.


Plants release oxygen during the process of photosynthesis. Carbon dioxide is exhaled by humans and other creatures and is again absorbed by plants. They use this carbon dioxide to create oxygen through photosynthesis, and thus the cycle continues.


The Phosphorous Cycle

Phosphorus travels throughout the hydrosphere, lithosphere, and biosphere in this biogeochemical cycle. The weathering of rocks releases phosphorus. Phosphorus is removed from the soil and water bodies by rain and erosion. With the soil and water, plants and animals absorb this phosphorus and develop. Phosphorus is also necessary for the growth of microorganisms. Following their decomposition, plants and animals release their stored phosphorus into the soil and water, where it is once more absorbed by flora and fauna, thereby perpetuating the cycle.


Cycle of Sulfur

This cycle of biogeochemistry passes via biological systems, bodies of water, and rocks. Rock weathering releases sulfur into the atmosphere, where it transforms into sulphates. Microorganisms and plants absorb these sulphates and transform them into organic forms. Animals ingest organic sulfur through diet. The cycle continues when the animals perish and decay, returning sulfur to the soil for the plants and bacteria to use.


Why Biogeochemical Cycles Are Important

The way the energy is consumed is shown by these cycles. These cycles transport the necessary components for life's sustenance throughout the biosphere. They are essential because they store and recycle components as well as controlling the essential elements through their physical aspects. These cycles allow ecosystems to continue to exist and show the relationships between living and non-living objects in the ecosystems.


Understanding these cycles is crucial if one is to understand how they affect living things. A couple of these natural cycles are disturbed by human activity, which has an impact on linked ecosystems. We can limit and halt these systems' harmful effects by taking a closer look at them.


Conclusion

biogeochemical cycles are the intricate threads weaving Earth's ecosystems. They regulate essential elements, support life, and highlight the delicate balance between living and non-living entities. Understanding and respecting these cycles are crucial for environmental sustainability. Human activities have disrupted this balance, emphasizing the need for responsible choices to preserve the interconnected processes that sustain life on our planet. By embracing this awareness, we can foster a harmonious coexistence with nature and ensure the well-being of our ecosystems for generations to come.


Note for UPSC Aspirants: For UPSC aspirants interested in exploring further, here are some keywords to guide your research: biogeochemical cycles, water cycle, carbon cycle, nitrogen cycle, oxygen cycle, phosphorous cycle, sulfur cycle, ecosystem, environmental sustainability, human impact, interconnected processes, life balance, responsible choices, nature coexistence.

Comments


bottom of page