Components Of an Ecosystem - Abiotic Components

All non-living components are called abiotic components. The abiotic components are further divided in to climatic, topographic and edaphic factors.
(a) Climatic Factors: 
  These factors are forming the aerial environment. These factors include.

1. Light
2. Temperature
3. Water
4. Atmosphere and Wind
5. Fire.

1. Light: It is one of the most important climatic factors which effects and regulates plant life in a very large variety of ways. The chief natural source of light is the sunlight. It is a form of radiant energy. It is an essential factor for the primary production of plant materials upon which all other living organisms depend directly or indirectly. However, the plants utilise only three percent of total light, which falls on earth. The light affects in three ways. i.e. light intensity, its duration and quality.

- Light Intensity: It depends upon angle of incidence and seasons, latitudes and time of the day. A normal amount of light is necessary for chlorophyll, formation. It also affects temperature.
   According to the requirement of light, plants are classified into two types. Plants those required bright light are called helophytes and plants those grow in shade are called sclorphytes.

- Light duration: It is required for growth and development of plants. Duration of light is called photo period. Due to different periods of light in summer and winter season the corps are also different.
       
-Light Quality: It is important, because only the visible light (range from 400 to 700 mill micron) that reaches the earth is utilised by man and other living organisms. Other types of light rays, such as ultraviolet and infrared are dangerous for living organisms.

2. Temperature: A normal and suitable temperature is required for the biochemical processes of animals and plants. Its main source is radiant energy of sun. In biosphere life mainly exists in the range of 0 to 50 c.
 There are three degrees of temperature.
(i)   Minimum temperature at which the metabolic processes begin.
(ii)  Optimum temperature, at which the metabolic processes are fast and rapid.
(iii)  Maximum temperature, at which the processes become slower and then finally stop.
    Due to temperature, different types of ecosystems are formed in the world and each ecosystem has its own kinds of plants and animals.

3. Water: Water is a very important climatic factor. It is essential for the life all living organisms. The main sources of water are rainfall, snow and dew. Of these rainfall is the most important, because the roots of plants directly absorb it. It is necessary for photosynthesis in plants. Continuously cycling of water in nature is called hydrological cycle. According to availability of water plants are classified into five types.

(i)  Xerophytes -------------   growing in dry places.

(ii)  Hydrophytes -----------   growing in wet places.

(iii) Halophytes -------------   growing in saline region.

(iv) Hygrophytes -----------   growing in moist places.

(v)  Mesophytes ------------- growing in normal places.

4. Atmosphere and Wind: Atmosphere plays an important role in the operation of ecosystem. Atmosphere is the gases envelop which surrounds the earth. Atmosphere contains nitrogen, oxygen, carbon dioxide and water vapours. Nitrogen enters the body of green plants in the form of nitrates and takes part in protein synthesis, oxygen is used for respiration and carbon dioxide is necessary for the photosynthesis. Moving air is called wind, when it blows fast, it becomes a storm. It affects the plants mechanically, their branches are broken and they may be uprooted. Other effect is that wind caries moist air to other place and it is replaced by dry air, therefore process of transpiration increase. The wind also influence migrate of flying animals. Wind generally moves from poles to equator.

4. Fire: The fire may be caused by lightning, volcanic activity, mutual friction between trees such as bamboos and mostly by man. The fire brings about sudden change in an ecosystem which has been developed in centuries. It recycles various nutrients and thus new growth is stimulated. Fire also brings about changes in environmental factors like light, rainfall, pH and nutrients. The fire also favours growth of some fungi, mostly ascomycetes and thus these fungi are called Pyrophilus fungi.