Ecosystems and Biomes: A Comprehensive Look at Earth’s Habitats
Ecosystems: Interconnectedness of Life
From Geosphere to Biosphere
Ecology is the science that studies the characteristics of living beings and the environment in which they live. Key concepts include:
- Biotope: The physical environment where living organisms of an ecosystem develop their life.
- Biocenosis: The community of living beings in a particular ecosystem.
- Habitat: The specific location where an organism lives.
Terrestrial and Aquatic Environments
- Terrestrial Environment: The surface of continents.
- Aquatic Environment: Composed of water bodies.
Environmental Factors
Environmental factors are the set of physical conditions that surround the biotope, including:
- Light
- Water
- Temperature
- Gases
- Soil composition
- Geographical location
Relationships within Biocenosis
Key relationships within a biocenosis include predation, parasitism, and symbiosis (e.g., fungi).
Environmental Fluctuations
Environmental changes, such as droughts, can be accidental or cyclical. Migrations are movements of individuals due to modifications of their habitat. A disproportion between predator and prey can cause significant changes in populations.
Producers, Consumers, and Decomposers
- Producers: Autotrophic organisms.
- Consumers: Heterotrophic organisms, including primary and secondary consumers.
- Decomposers: Heterotrophic organisms that break down organic matter.
Food Chains and Food Webs
- Food Chain: A linear representation of energy transfer in an ecosystem.
- Food Web: A representation of interconnected food chains.
Matter and Energy Flow
- Cycle of Matter: The movement of matter through trophic levels.
- Energy Flow: The circulation of energy from producers to higher trophic levels.
- Biomass: The total mass of living organisms in a given area.
Aquatic Ecosystems
Factors influencing aquatic ecosystems include light, temperature, salinity, and dissolved oxygen.
Marine Ecosystems
- Neritic Zone: Waters over the continental shelf.
- Pelagic Zone: Waters beyond the continental shelf, further divided into:
- Epipelagic
- Bathyal
- Abyssal
Freshwater Ecosystems
Freshwater ecosystems make up 3% of the hydrosphere and 1% of surface waters. They include rivers, lakes, lagoons, and wetlands, and are divided into upper, middle, and lower courses.
Terrestrial Ecosystems
Terrestrial ecosystems are characterized by water scarcity, low air density, and temperature oscillations. They are classified by latitude:
- Tropical Latitudes: Near the equator.
- Temperate Latitudes: Hot summers and cold winters.
- Polar Latitudes: Near the poles.
Major Biomes
Mediterranean Forest
Temperature: 15-20°C, with mild winters and hot summers. Vegetation is characterized by a predominance of trees and shrubs. Animals include wild goats.
Deciduous Forest
Temperature: 8-14°C, with temperate summers and cold winters. Vegetation adapts to the cold. Animals include deer.
Desert
Temperature: 20-30°C, with cool nights and warm days. Biomass is reduced, and animals are often nocturnal.
Steppe
Temperature: 3-16°C, with significant temperature oscillation between day and night. Vegetation is primarily herbaceous. Animals include bison.
Taiga (Boreal Forest)
Temperature: Around 0°C, with long, cold winters. Vegetation includes pine and fir trees. Animals include the Arctic hare and snowy owl.
Tundra
Temperature: Below 0°C in the short summer. Animals include polar bears. Plants are sparse.
Savanna
Temperature: Around 25°C, with abundant rainfall. Vegetation includes extensive meadows, trees, and shrubs. Animals include zebras and lions.
Rainforest
Temperature: 24-27°C, with high rainfall. Trees are large. Animals include invertebrates, reptiles, and birds.