Eco-system: What are it’s components?
- Non living things and the living things together form an ecosystem. And hence ecosystem consist of biotic components such as living organisms and abiotic components like temperature, rainfall, wind, soil and minerals.
- We all know that, organisms are classified or grouped as producers, consumers and decomposers on the basis of their sustenance in the environment.
- So all the green plants and specific bacteria which produces their own food by photosynthesis are called as producers.
- Then consumers are the organisms which consumes food produced by the producers either directly or indirectly.
- Consumers are again classified as herbivores, carnivores, omnivores and parasites.
Food chains and Webs:
- The group of organisms which involves in various biotic levels forms the food chain.
- Each step or level in the food chain is called as trophic level.
- Autotrophs or producers belongs to the first trophic level. They makes available energy for heterotrophs or consumers.
- Herbivores are the primary consumers which belongs to second trophic level, small carnivores are the secondary consumers which belongs to third trophic level, larger carnivores which are called as tertiary consumers belongs to fourth trophic level.
- Food eaten by us gives us energy to do work. The energy flow from one trophic level to next trophic level forms the food chain.
- The flow of energy is unidirectional.
- Also, the energy produced at each trophic level get diminished due to loss of energy at each level.
- Through the food chain some harmful chemicals enters in our body. Since to protect crops from disease and pests we use pesticides and other chemicals also.
- These chemicals after wash down get mixed into he soil or in water.
- These chemicals then will be absorbed by the plants with minerals and water also and from the water these chemicals are taken up by aquatic animals and plants. In this way they enters the food chain. This chemicals get accumulated progressively at each trophic level because they can’t be degradable.
- As human being are at the top of food chain hence most of the chemical concentration is found in our body. This phenomenon is called as biological magnification.
How do our activities affect the environment:
- The changes in the environment affects to our life and the changes in our life also cause the changes in the environment.
- We see the two environmental problems namely ozone layer depletion and waste disposal.
Ozone layer and how it is getting depleted:
- Ozone molecule is made form three oxygen atoms and having molecular formula as O3. Oxygen O2 is the essential for all living organisms. Ozone layer on the earth’s surface protect us from UV rays coming from the sun which highly harmful to human beings.
- When UV radiation acts on the oxygen molecule at the higher level of atmosphere then oxygen molecule get splited into free oxygen atoms.
- Again these free oxygen atoms combine with the oxygen molecule and forms the molecule of ozone.
O2 ———> O + O
O + O2 ——> O3
- The CFCs coming from refrigerator and fire extinguishers leads to depletion in ozone layer.
Managing the Garbage we produce:
- The human made substances like plastics cannot be degradable be the bacteria or saprophytes.
- These plastics material cannot be easily degradable and remain as it is for long time duration.
- The substances which get degradable by the bacteria are called as biodegradable. And the substances which cannot get broken by the bacteria are called as non biodegradable.
- To avoid ozone layer depletion and pollution we have to manage the Garbage produced and we have to use paper rather than plastic which is easily degradable.
- We have to reuse the plastics and thereby we can decrease air pollution.