2. INTRODUCTION
ECOLOGY
• The science that studies the relationship among organism and the
environments in which they live, including all living and non-living
components.
• The term ecology comes from the Greek word “oikos” meaning house.
It was coined by German scientist Ernst Haeckel in 1866.
3. IMPORTANCE OF ECOLOGY
Our planet earth is the house which all organism reside.
When a problem affects the environment it also affects the
organisms that live there because of their interrelationship.
This field of study is important to human beings in two ways:
• It provides the knowledge that we have to deal effectively with
environmental considerations
• Human beings affect and are affected by the environment.
Man makes changes in the environment and therefore
influences the relationship of the all living organisms within the
environment. Changes can affect the physical such as the air and
water quality and the conditions of the land. People have to
understand that altering one aspect of the environment changes the
entire system.
4. SUBDIVISION OF ECOLOGY
1. Autecology
-Deals with the study of the individual organism, its life history, behavior,
characteristics, and its adaptation to the environment.
2. Synecology
-Deals with the study of group of organisms with are associated as a unit
of relation to its environment.
6. INTERACTION IN AN ECOSYSTEM
There are three kinds of interactions in an ecosystem:
1. Abiotic-abiotic
-Interaction relationship among physical factors in the environment.
2. Biotic-biotic
-Interaction relationship among biotic factors in the community.
3. Biotic-abiotic
-Relationship between living and non-living things in a community.
7. Abiotic factors
1. WATER
Importance of Water
• Helps in the germination of seed
• Transports subtances in the body of plant and animal
• Aids in the erosion and breaking of rocks.
• Is needed to support plant tissue
• Comprises a large percent of the body tissue of an organism
Plants Water Requirements:
Hydrophytes
-those plants that thrive in places where the amount of water is abundant, usually fresh water
plant (e.g. Lotus and water lettuce)
Halophytes
-Plants thriving in a place where the water available contains much dissolve salts. The sea or
ocean where plants inhabit has abundant supply of water, but due to its concentration, the plant
absorbs it with difficulty. (e.g. mangrove, nipa and algae)
Mesophytes
-Most of our plants bearing flowers and fruits are classified mesophytes.
-They need a moderate supply of water for their sub existence.
8. XEROPHYTES
- Plants that can tolerate where water supply is very scanty.
- A plant which thrives in dry places likes deserts and other dry areas.
Example: Cacti and maguey
TROPOPHYTES
-These plants that can adapt itself year after year where seasonal changes bring
marked change in the amount of available water from the soil.
Example: Rose plants
9. 2. SOIL
• It is made of particles of inorganic and organic matter such as bacteria, protozoa,
algae, fungi, etc.
• They are formed from broken rocks and by disintegration action of living things and
climate.
Types of Soil:
According to the kind of materials and size of its particles
a.. Sandy
- Inorganic soil particles that is larger than clay or silt.
- Plants do not grow well here because water goes rapidly through the spaces
between particles, and water dries off quickly.
- Its size is about 1mm. to 0.05mm in diameter.
b. Clay
- Smallest inorganic particle of soil compared with silt and sand.
- It retains water before drying; it is sticky and not suitable for plant growth
- Water moves very slowly.
- It is often damp and poorly drained, about 0,005 mm in diameter.
10. c. Loam
- Soil which is good for agriculture and made up of particles of gravel and clay
with the addition of organic materials called Humus with 1 to 2mm in
diameter
d. Silt
- Made up of very fine particles of soil or clay, deposited as sediments.
- It is about 0.05 to 0.005 mm in diameter.
11. 3. Sunlight
- An important physical factor.
- Made life possible on earth.
- It pursues the process of photosynthesis on which organisms depend for the
manufacture of food.
- It has been the main source of and the oldest of all energy sources, since the
creation of the earth. of the earth axis.
4. Temperature
- Another abiotic factor of the ecosystems
- It is directly proportional to the intensity of light.
- Every organism has different level of tolerance for temperature
12. BIOTIC FACTORS
These are the living components of the ecosystem which includes plants,
animals, and microorganisms
Biological Relationships:
a. Intraspecific Relationships
- It includes mating, assistance gregariousness, and competition.
- Organisms belonging to the same species must compete with one another for
space, food and mates.
b. Interspecific Relationships
- Different species must struggle with each other for space and food
- Since many species use other kinds of animals for food, each habitat includes
predaceous animals.
- Another type of these relations involves associations that are more intimate
and are known as commensalisms, symbiosis and parasitism.
