Living beings and biogeochemical cycles, activated by solar radiation, have a close relationship of dependence that marks the ecosystem balance of life and of our planet. They present a cyclical or closed movement because they circulate and are recycled, unlike the flow of energy in ecosystems that is open.
Knowing these and other characteristics of biogeochemical cycles helps to understand the dynamics of ecosystems and how human activities are capable of altering them. If you want to learn more about what are biogeochemical cycles, their types and importance, keep reading this article by Ecologist Verde, where you can also consult some examples of biogeochemical cycles.
What are biogeochemical cycles
The biogeochemical cycles or BGQ cycles They are processes that guarantee the constant recycling, at a higher or lower speed, of those elements that are strictly necessary for life and our survival (nutrients), by converting them from organic to mineral and vice versa.
In these cycles of nature, macronutrients and micronutrients that constitute the inorganic matter present in our environment (air, water or soil), are incorporated into organisms as organic matter, through metabolic processes and, subsequently, return to the natural environment, in their inorganic form.
Macronutrients (C, H, O, N, P, S) constitute more than 95% of the biomass of all living beings and are those elements that our body requires in large quantities for its development, maintenance and reproduction.
Although they are also essential, unlike macronutrients, micronutrients they have a minor presence in the body. Some examples of biogeochemical cycles in micronutrients are: iron (Fe), copper (Cu), zinc (Zn), chlorine (Cl) and iodine (I).
Types of biogeochemical cycles
The classification of biogeochemical cycles It can be established according to their complexity and mobility.
Attending to the complexity of BGQ cycles, these might be:
- Simple cycles: where the elements are more influenced by physical-chemical forces than by biological ones. Eg: salts and trace elements.
- Intermediate cycles: made up of elements of organic matter (OM) that can be easily released (C, H, O, P).
- Complex cycles: associated with elements of OM that require specialized microorganisms in their complex transformations (N and S).
In function of your mobility, we can distinguish:
- Global cycles: They are those that have gaseous phases, which allows their distribution on a global scale.
- Local cycles: they are less mobile, more sedimentary cycles, which end up being transported by water, accumulating in sediments, which gives rise to a more regional or local distribution (P, K, Ca).
There are also three types of biogeochemical cycles interconnected:
- Gaseous: macro and micronutrients are rapidly recycled and circulate between the atmosphere and living things. The oxygen, carbon and nitrogen cycle stand out.
- Sedimentary: elements (eg phosphorus and sulfur) circulate between the earth's crust, hydrosphere, and organisms and are recycled at a slower rate than the gas cycle.
- Hydrological or water cycle. In this other post you can learn about What is the water cycle.
Carbon cycle
The carbon cycle It is essential because it forms the organic matter and represents the exchanges between organisms and the environment, as a consequence of the processes of respiration and photosynthesis.
As usual, carbon is recycled quicklyalthough it may remain in unavailable forms for long periods. In hot and humid ecosystems (tropical rainforest), production and decomposition rates are high, and C (carbon) circulates rapidly through the ecosystem. On the contrary, in cold and dry ecosystems the process is slower.
Learn more about what the carbon cycle is, how it works and its importance with this other article.
Sulfur cycle
This item has sedimentary and gaseous phases.
- On the one hand, in the sedimentary one, the sulfur that is immobilized in organic and inorganic deposits is released by wear and tear and by decomposition processes until it is transported to terrestrial ecosystems in the form of saline solution.
- On the other hand, the gaseous phase of the biogeochemical sulfur cycle allows its circulation on a global scale.
Image: Slideshare
Phosphorus cycle
The biogeochemical phosphorus cycle It does not present a significant atmospheric reservoir, as it is found in mineral deposits and marine sediments, in unavailable forms.
It is released to terrestrial ecosystems and aquatic ecosystems by rock erosion and mining extraction, mainly.
Importance of biogeochemical cycles
The importance of biogeochemical cycles It is given by the benefits they report and by their characteristics:
- First of all, these cycles allow life on Earth, maintaining optimal conditions. This means that biogeochemical cycles regulate the climate, the distribution of nutrients …
- They also make possible matter exchanges between living beings and the natural environment and access to the vital elements (nutrients) that we need.
In this other article you can read more about the Characteristics of planet Earth that make life possible.
What human activities have modified biogeochemical cycles
Below are shown examples of biogeochemical cycles altered by human activities:
- Deforestation alters the water cycle leading to the desertification of ecosystems.
- Wastewater discharges, intensive agriculture and the use of fertilizers (eutrophication) modify the nitrogen and sulfur cycles, favoring acid rain.
- Large-scale fishing activities alter bacterioplankton, and the C, N, O and P cycles, which it regulates, can be modified.
- Industrial activities and the burning of fossil fuels modify, among others (such as the S) the carbon cycle, causing global warming.
If you want to read more articles similar to Biogeochemical cycles: what are they, types and importance, we recommend that you enter our Biology category.
