Ecological Concepts

Ecology is the study of how living organisms interact with each other and their surroundings. It forms the foundation for understanding fields like agriculture, forestry, and fisheries. Scientists who study ecology are called ecologists. Also referred to as environmental biology, ecology has two main branches:

1. Autecology: Focuses on the study of a single organism or species and its environment. For example, studying Tilapia fish in a specific stream.
2. Synecology: Examines the relationships between groups of organisms or species within a shared area. For instance, studying all organisms in a stream and their interactions with the environment.

Key Ecological Concepts

Understanding ecology involves several key concepts, including:

1. Environment: All external and internal factors, both living and non-living, that affect an organism.
2. Biosphere or Ecosphere: The Earth's zone occupied by living organisms. It consists of:
• Lithosphere: The land portion of Earth.
• Hydrosphere: The water portion of Earth.
• Atmosphere: The air surrounding Earth.
3. Habitat: The specific place where an organism lives.
4. Niche: The role an organism plays in its interactions with others.
5. Population: The total number of organisms of a specific species living in a particular area.
6. Ecosystem: A system comprising living organisms interacting with each other and their non-living environment (e.g., weather, soil, sunlight, and atmosphere).

Components of an Ecosystem

Ecosystems have two main components: biotic (living) and abiotic (non-living).

1. Biotic Components: These include all living organisms in the environment and are classified as:
• Producers: Autotrophs like green plants that create their own food through photosynthesis or chemosynthesis.
• Consumers: Heterotrophs like animals that depend on plants directly or indirectly for food. Consumers are categorized as primary, secondary, or tertiary.
• Decomposers: Organisms like fungi and bacteria that break down dead plants and animals, recycling nutrients back to the soil.
2. Abiotic Components: These consist of:
• Abiotic Resources: Elements necessary for life, such as sunlight and nutrients like water, nitrogen, and carbon dioxide.
• Abiotic Conditions: Environmental factors that influence the presence, growth, and behavior of organisms. Examples include:
• Edaphic Factors: Soil, rocks, and topography.
• Climatic Factors: Temperature, wind, light intensity, humidity, rainfall, and water currents.

Measuring Ecological Factors

Interactions in an Ecosystem

In ecosystems, components interact uniquely:

Green plants use sunlight, water, and carbon dioxide to produce carbohydrates through photosynthesis. Animals consume these carbohydrates and release carbon dioxide, which plants absorb. Decomposers break down dead organisms, returning nutrients to the soil for plants to use. During photosynthesis, plants release oxygen, which animals rely on for respiration.