A simplified explanation of the connection between positive feedback mechanisms and biodiversity
When analysing positive feedback mechanisms and their effects on the environment and more specifically, on the biodiversity of the environment, we need to define the terms that provide an explanation on the origins of these procedures. In order to understand the connection between the diversity of the environment and balancing mechanisms, this article helps you by providing information on the different types of equilibria, by explaining how positive feedback procedures function and its, direct or indirect, impact on the sustainable development and replenishment of resources.
The three types of different equilibria are categorized as stable, neutral and unstable. An analysis of the neutral equilibria won’t be included, due to the fact that there is no relation with the themes examined.
At the first place, we examine stable equilibria as the definition for systems which, after being disturbed and distracted, are able to return to their original form. When this cycle occurs on the equilibrium of living organisms, homeostasis is the most precise word. Homeostasis is the tendency of living bions to resist any changes in their equilibrium. For example, when someone runs and the body temperature rises, it is obvious that after the activation of some mechanisms in the body, the temperature will fall again. The return to the original form is what makes it a stable equilibrium.
Secondly, unstable equilibria is the definition for the systems that can’t resist changes and after the interruption of their usual procedure, they form new equilibria. Those systems are linked to positive feedback mechanisms. Positive feedback is a mechanism that occurs when the end product of an action amplifies the action. For instance, if the action is A and the end product is B, B will contribute to the increase of action A. As mentioned, positive feedback mechanisms are forming new equilibria and therefore, systems might experience disturbance or damage.
But, why positive feedback mechanisms are associated with harm for the ecosystems? To answer this question, we need to take into account the damage that the mechanism causes. The majority of the time, the disturbed ecosystem might indirectly contribute in reaching the tipping points of various parts in the environment. Tipping points are critical points of systems, which are caused by the instability and lead to a negative and many times irreversible development. When positive feedback loops drive systems towards their tipping points or the ‘threshold of change’, we experience dramatic effects on the overall system. Reaching a tipping point can have a huge and negative impact on small ecosystems as well as bigger environmental factors such as climate change, pollution or sustainability.
In this article, the aim of explaining the impact of positive feedback mechanisms on biodiversity can only be achieved by understanding what is meant by diversity in the millions of ecosystems of the environment. Biodiversity can be considered a broad concept including diversity of species, habitat diversity and genetic diversity. Habitat diversity, which refers to the range of different habitats in an ecosystem, is the most important component due to the fact that its increase will increase the diversity of both species and genetics. Genetic diversity refers to the wide and varying genetic material present in a population of a species, and species diversity considers the variety of species per unit area. Overall, the term biodiversity is used to explain the variability between the species, the genetic level and the habitats, in a community or an ecosystem.
Understanding the connection between positive feedback mechanisms and biodiversity can be considered a complex task and therefore, the use of a simple example is required. The procedure of deforestation can provide answers on how a positive feedback mechanism can have grave long-term consequences on biodiversity of ecosystems.
Deforestation is an example of a positive feedback mechanism which is visible and is great enough to affect the environment. The procedure of cutting trees and disturbing the balance of forests for building houses, making paper and other purposes can be unsustainable and excessive. Since less trees are available for evapotranspiration, the water cycle is damaged and the balance of rainfall is disturbed. As a result, in the regions where deforestation occurred, rain is reduced and droughts increase. The grave consequence of this problem is the vulnerability of forest fires, due to the dry environment. One fire would be enough to harm other forests and damage, in the same way, other regions. Fires cannot be easily limited and in most of the cases, deforestation can have a ‘domino effect’ and affect thousands of acres, in ‘neighboring’ regions.
The positive feedback mechanism is clearly articulated in the model above. In this system, the end product increases the intensity of the action that it came from. The question is: What happens after the devastation of all these forests? Where is the tipping point of the environment after losing so many trees? Provided that grave forest fires continue to exist, tipping points will be reached more intensely every time, with the state of the ecosystems changing dramatically. After many years, biodiversity will be completely damaged due to the loss of habitats, species and genetic material. Additionally, excessive atmospheric pollution, climate change and disturbance of the water cycle will also affect biodiversity in the long-term.
The connection between positive feedback mechanisms and biodiversity can be a severely damaging procedure and the fact that there can be such grave and catastrophic long-term effects from deforestation can be considered ‘food for thought’, for the levels of destruction caused by bigger or equally enormous positive feedback mechanisms.
Davis, Andrew, and Garrett Nagle. Environmental Systems and Societies. Pearson Education Limited, 2015.
Nagle, Garrett. Environmental Systems and Societies for the Ib Diploma Study and Revision g. Hodder Education, 2017.
“Human Ecology — Basic Concepts for Sustainable Development.” Gerry Marten | Human Ecology — Populations and Feedback Systems
Nepstad, Daniel C, et al. “Interactions among Amazon Land Use, Forests, and Climate: Prospects for a near-Term Forest Tipping Point.” Philosophical Transactions of the Royal Society B: Biological Sciences, The Royal Society, 27 May 2008, rstb.royalsocietypublishing.org/content/363/1498/1737.short.9