DYNAMICECOSYSTEM

Chapter 8:

321

ABIOTIC COMPONENTS (physical factor)

The non-living components in the ecosystem such as air, water, soil temperature and light intensity

ABIOTIC COMPONENTS

pH level

Temperature

Light intensity

Humidity

Topography

Microclimate

Poikilotherms

HomoiothermsAltitude

Gradient/Slope

Aspect

Most organisms live in a neutral or nearly neutral environment.

Some plants, like maize, grows well in an acidic condition.

while coconuts grow well in an alkaline condition.

pH VALUE

POIKILOTHERMS- Are animals that cannot control their body

temperature with the environmental temperature.

HOMOITHERMS- Are animals that can maintain their body

temperature

TEMPERATURE

The sun is the source of energy for photosynthesis in plants.The varying intensities of sunlight in a forest result in the growth of different types of plants.For example, tall trees that are exposed to high intensity of sunlight form the canopy of a forest, while plants such as ferns and vines survive under the cover of shady trees.All organisms that live in soil prefer a dark environment (low light intensity).

Light Intensity

The amount of water vapour present in the air.The humidity of air affects the rate of water loss by plants and animals.When humidity is low, water evaporates from the moist surfaces at a faster rates.Humidity is usually higher at night but lower during the day.Organisms such as frogs, snails, earthworms and moss that cannot control the rate of water loss are more suited to live in damp places.

HUMIDITY

Altitude -There are less organisms at high altitudes because temperature,

atmospheric pressure an air humidity are law. -Different plants are found at different altitudes.

Gradient/slope -The gradient of a place affects the rate of water flow. -In steep areas, the swift flow of water causes soil erosion while in flat areas,

the water is stagnant.(these 2 areas are not suitable for plants and animals to live)Aspect

-Aspect refers to the direction facing or opposing the wind and sunlight. -Areas facing aspects are not suitable for living and hence, have less

organisms.

TOPOGRAPHY

MICROCLIMATE

Refers to the climate in a microhabitat.

Microclimate includes humidity, light intensity and atmospheric conditions in which the organisms live.

Influences the number and distribution of organisms.