Ecosystem Meaning: The growth and reproduction of all living organisms are affected by the environment in which they live. The reciprocal relationships between organisms and their environment are primarily studied at the levels of population, community and ecosystem, which represent a hierarchy of organization with increasing complexity. Ecosystems provide a variety of services to mankind. They also provides many resources for use such as food, fodder, shelter etc.
However, the increasing human activities, especially during last millennium, have adversely affected this unique balance of nature. Such activities are also leading to an increase in green house gases in the atmosphere causing the recently recognized phenomenon of global warming and ozone hole. Thus, human activities many convert Natural Ecosystem into anthropogenic or man made ecosystems.
For Example, natural forests have been cut and the land converted to tree plantations or agricultural systems. Space Crafts and aquariums may also be considered as man-made ecosystems.
Ecosystem Meaning
The Ecosystems are parts of nature where living organisms (biotic) and their non-living (biotic) environment are inseparably interrelated and interact upon each other. The term ‘ecosystem’ was coined by Sir Arthur Tansley (British ecologist) in 1935.
Ecosystems may be defined as a dynamic system which includes both biotic components and biotic environment influencing the properties of each other and both necessary for the maintenance of life. Ecosystems are recognized as self-regulating and self-sustaining units of landscape.
Components of Ecosystems
The principal components of ecosystems have been identified for rain forests (Cyclobalanostata) and marine environments (Protobalanostata), and many of the observed synergies can be found in my eliminated neurons (i.e., a subset of neurons).
We show how synergies may arise from feedback between cells to produce major and minor axis interactions that play crucial roles in wiring up the neurons into a network. We show that myelin receptors mediate crosstalk between major and minor axis, and that large-scale network dynamics act to mediate feedback between cells and the global network.
These interactions can be modeled in closed systems, and show how feedback’s from myelin can be used to implement network hypotheses in models of network connectivity.
Sustained physical exercise is recognized as an important contributor to longevity (Pratico et al., 2002), as well as the activation of noninvasive repair mechanisms in muscles, and it has also been shown that exercise is associated with neurogenesis in the brain (McMahon et al., 2001). As a consequence, many researchers have suggested that exercise can be considered as a form of preventive medicine for neurodegenerative disorders.
However, the effects of exercise on health also result from mechanisms involving neural transmission, and while it is not known whether the effects of exercise on synaptic strength are mediated by nonneuronal mechanisms remains unclear. One possibility is that the neuroplastic mechanisms of exercise result in plastic changes in synaptic structure.
Such changes in synaptic function are expected to lead to major axis-configuration interactions, which could modulate networks and play an important role in the enhancement of adaptive plasticity (Morton and Busby, 2008).
One potential mechanism is connectivity, that is, that individual neurons interact to form larger circuits that function as a functional, network-like system (Patel and Ashwell, 1996; Finke and Wolf, 2002; Bullock et al., 2007). Such networks can also become abnormally strong, possibly due to synaptic dysfunctions such as pruning, which can reduce the strength of the existing synaptic connections between neurons (Finke and Wolf, 2002).
However, the interactions between major and minor axes must be conserved, because altered positions of the major axis will alter connectivity between neurons (Todorov, 1981).
Major and minor axis-configuration interactions are mainly observed in (m)ice brains. These studies have shown that the interactions between neurons and networks are critical for synaptic plasticity, and thus could be the driving force behind the formation of large-scale networks (Bullock et al., 2007). However, major axis interactions appear not to occur in the brains of humans (LaVallee and Schaller, 1996), so the underlying mechanisms remain unknown.
An Ecosystem comprises basically two components and i.e. Abiotic (non-living) and Biotic (Living organism):
A. Abiotic Components: The Abiotic components of ecosystem are present in Soil, water and air. It comprises following non-living material:
a) Inorganic substances: Inorganic materials like carbon, oxygen, nitrogen, carbon dioxide phosphorous, water etc. These substances are converted is to are involved in the material cycle of ecosystem.
b) Organic components: These are proteins, carbohydrates, lipids, humic substances and so on that links abiotic and biotic components.
c) Climate regime: it includes temperature, light and other physical factors that delimit the conditions of existence.
For the functioning of an ecosystem, the sunlight is essential. The plants receive the sunlight and fix it in the form of organic compounds.
B. Biotic Components: The Biotic components of ecosystems comprises living organisms i.e. producers, consumers and decomposers.
a) Producers: Green plants and other autotrophic (self nourishing) organisms such as algae and diatoms that can take energy from the non-living environment and make it available to all living organisms are called as producers. Producers convert the light energy of the sun into potential chemical energy in the form of organic compounds.
b) Consumers: These are also called as macro-consumers photographs. Consumers are heterotrophic organisms that obtain their energy from sources other than themselves, directly or indirectly. Consumers can be categories into following:
I) Primary Consumers: They derive their nutrition by cutting plants. For example, rabbit, grass etc.
II) Secondary Consumers: consumers are animals that devour the flesh of herbivorous. For example: frog, big fish etc.
III) Tertiary consumers: Tertiary consumers feed upon secondary consumers. For Eg., whale, snake etc.
c) Decomposers: Decomposers or saprotrophs are other heterotrophic organisms (mainly bacteria and fungi) which have on dead organic matter or detritus. Instead they release different enzymes from the bodies into the dead and decaying plant and animal remains. The extracellular digestion of here dead remains, leads to the release of simpler inorganic substances which are then utilized by the decomposers.
