Understanding Ecology and Ecosystems
Ever wondered why certain animals only live in specific places? Ecology is the study of interactions between living things and their environment - basically, it's nature's rulebook for survival.
Your habitat is where you live (your house and neighbourhood), whilst an ecosystem includes all the living organisms in an area plus their physical environment working together as a unit. Think of it like a massive outdoor community where everyone depends on each other.
The biosphere is the part of Earth containing all living organisms - from the deepest ocean trenches to the highest mountains. Within ecosystems, we organise life into levels: individual organisms form populations (all members of the same species in an area), and different populations create a community.
Key Point: Remember the hierarchy - individual → population → community → ecosystem → biosphere. Each level gets bigger and more complex!
Environmental Factors and Energy Flow
Two main types of factors affect where organisms can survive: biotic factors (living things like competitors, predators, diseases) and abiotic factors (non-living things like temperature, rainfall, soil type, and pH).
Producers are the superstars of any ecosystem - these autotrophs make their own food through photosynthesis, trapping energy in glucose and starch. Consumers (all animals) are heterotrophs that get energy by eating other organisms.
Here's the crucial bit: only 10% of energy passes from one trophic level to the next, whilst 90% is used for growth, repair, or lost as heat. This is why food chains are relatively short - there simply isn't enough energy to support many levels.
A food web consists of interconnected food chains, showing the complex feeding relationships in nature. The carbon cycle keeps carbon moving between the atmosphere (as CO₂), living organisms, and the environment through photosynthesis, respiration, and decomposition.
