Ecological Succession PDF

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Ecological Succession...

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ECOLOGICAL SUCCESSION

Environmental succession is a process of action in which a community gradually alters itself until it becomes a stable community. Ecological communities are formed on the basis of this fundamental principle, and any alteration that occurs is a comparatively expected part of the process of ecological community formation. The production of new, vacant habitat (e.g., a lava flow or a major landslide) or some type of disruption (e.g., fire, extreme wind throw, logging) of an existing community are the two primary mechanisms by which succession occurs. There are two types of succession: primary succession and secondary succession. Primary succession is the most common type. Primary succession is a sequence of community transformation that occurs on a completely new environment that has never been colonised previously, such as a newly quarried rock face or sand dunes. Secondary succession, on the other hand, is a chain of community transformation that occurs on a previously colonised, albeit disturbed or damaged habitat, such as a forest after trees have been cut down, land cleared, or a fire. Additionally, primary succession begins in locations where there is no soil at the outset, whereas secondary succession occurs in areas where soil has already developed.

Ecological succession is the process through which the structure of species in an ecological community changes over time as a result of the interaction of these species. This process can result in some species becoming abundant or the appearance of new species in an ecosystem, or it might cause some species to completely disappear from an ecosystem. The term "ecological succession" refers to the visible transition that

occurs through time in the organisms that live in a particular ecosystem.

Now, the question arises as to why this phenomenon of ecological succession occurs in the first place. We can all agree that every species requires a specific optimal natural condition that is conducive for its growth and reproduction in order to thrive. The abundance of all species in a given ecosystem will increase in such a setting because those species that are best suited to the environment will be able to develop and reproduce. Therefore, if the environmental circumstances in an ecosystem remain constant, the species that are best adapted to those conditions will thrive. Although the initial environment may have been highly favourable for the first species, whether it was a plant or an animal, the modified environment is frequently favourable for other plant or animal species as well. With the change in the condition of the environment, it is possible that the formerly dominating species will no longer thrive and that another species may expand in number.

Ecological succession can also occur when the conditions of an environment change suddenly and dramatically, as in a natural disaster. Conditions such as forest fires and wind storms, as well as human activities such as agriculture, all play a substantial role in altering the conditions of an area. Species extinction can occur as a result of these massive forces, which alters the dynamics of the ecosystem and causes a rush for supremacy among the species that remain in the ecological community.

The concept of succession is extremely important in this context. As a community develops, it follows a very well defined and predictable pattern through various stages of development until reaching the final stage, each with a

different measure of efficiency and diversity than the previous stage. The stages of succession are concerned with the classification system of a certain group as well as the way in which that group interacts with its environment. For example, certain factions of the modern-day Maya believe that once land has been cleared for agriculture, the forest regrowth process proceeds through six stages. In appreciating the succession and its associated agricultural implications, which are vital to the timing of the land's re-use for agriculture, this becomes important. Despite the fact that the processes involved in succession are the same throughout the world, the specific species involved in the process in a specific area are influenced by the geology and history of the area, the climate and microclimates present, the weather, the type of soil present, and other environmental variables. Although the time period of succession is not predetermined, it can span anywhere from a few days to hundreds of years, depending on the circumstances. In contrast, the succession of invertebrates and fungus within a single cow dung can be completed in as little as three months, during which the dung has been transformed into humus and nutrients that can be recycled back into the ground. The holes that can clearly be seen in the cow dung are the consequence of animals that have colonised the area and eaten the faeces.

Is man influenced by the process of ecological succession? The answer is yes, as you might expect. Ecological succession is not a man-made phenomenon, but rather a natural phenomenon. Our understanding of ecosystems is that they are constantly changing and rearranging themselves. Let us consider an example to better understand how ecological succession affects humans and to appreciate the incredible amount of work and money that goes into ecological succession. Consider the sight of a freshly ploughed garden plot. The clearing of land for the purpose of

preparing the soil for new planting has resulted in the disturbance and restructuring of the previously stable ecosystem—this is a big external event caused by man and carried out on a large scale. The disturbance of the ecosystem will cause the progression of ecological succession to begin as soon as possible.

Is it possible for ecological succession to reach a point of no return? In ecological succession, there is a concept known as the "climax" community, which refers to the community that has reached its peak. An earlier school of thought held that ecological succession eventually reached a stable end-stage known as the climax, after which it would cease to exist. Modern ecologists have rejected this hypothesis in favour of non-equilibrium theories of how ecosystems function, which they believe are more accurate. The climax community is characterised by a stable end product that is produced by the sequence of events. There are some plant species that have the ability to maintain themselves for an extremely long period of time, meaning that their structure and composition do not change noticeably throughout a period of time that may be observed. We can reasonably conclude that ecological succession has come to a halt at this point. However, it is a well-known truth that any ecosystem, no matter how well established and stable it may be, is susceptible to significant external disturbing factors such as fires and storms, which have the potential to rearrange and re-start the succession process. It is wrong to believe that succession has come to an end until these possible tragedies manifest themselves. Over lengthy periods of time, there is a change in the climate conditions and other original characteristics of an ecosystem, which should be taken into consideration. Although these changes are not visible in our "ecological" period, it is apparent that their essential existence and historical actuality are not in question.

This means that on a geological time scale, no ecosystem, whether past or future, will be able to sustain itself without being altered or corrected. Take, for example, the concept of climax vegetation: In the aftermath of a forest fire, the vegetation passes through a series of stages that are called stages of succession. They start with grass and herbs, then move on to shrubs and vines, then weedy trees, and finally the "climax forest" that forms under the weedy trees at the end of the process. The climax vegetation continues to grow until the next fire is ignited. However, there is never a model that is so straightforward and static.

Plant species that have adapted to the altered soil conditions would take over the landscape. It is primarily weeds that take over, even though they play an important ecological role and function. Weeds, on the other hand, are fighting for nutrients, water, and physical space among the garden plants. If left ignored, the garden would quickly become plagued with weeds that are extremely productive, and the garden plants would struggle to maintain their health and viability. The only method to deal with the situation is to weed the garden, which takes a significant amount of time and effort. It is important to note that this energy contribution is precisely proportionate to the amount of "energy" contained within the force of ecological succession. Consider how much work would be required of all of the farmers and gardeners who are responsible for growing our food if this small-scale situation were to be replicated throughout all of the agricultural fields and systems on the planet. This provides you an indication of the enormous cost in terms of time, gasoline, herbicides, and pesticides that we incur every growing season as a result of the force of ecological succession on our agricultural operations. Although ecology has extended its wings throughout the world, the contributions of different cultures to ecology are hampered by language and translation barriers....