Summary of Fundamentals of Environmental Science
Fundamentals of Environmental Science: A Student Guide
Introduction
Ecosystems are functional units where living organisms interact with each other and with non-living elements of their environment. This study material explains the components, energy flow, main types, ecosystem functions and services, human relationships with natural environments, and practical examples to help you understand how ecosystems support life and human well-being.
Definition: An ecosystem is a dynamic community of plants, animals, microorganisms, and their non-living environment interacting as a functional unit.
1. Components of an Ecosystem
1.1 Biotic and Abiotic Components
- Biotic components: producers (plants), consumers (animals), decomposers (fungi, bacteria).
- Abiotic components: inorganic materials (carbon, nitrogen), and physical factors (sunlight, temperature, water).
Definition: Biotic components are the living parts of an ecosystem; abiotic components are the non-living physical and chemical factors.
Examples and applications
- A forest: trees (producers), deer (primary consumers), wolves (secondary consumers), fungi (decomposers), soil nutrients and rainfall (abiotic).
- An aquarium: plants and fish (biotic), water chemistry and light (abiotic).
2. Energy Flow and Food Chains
Energy enters most ecosystems as sunlight and is captured by producers through photosynthesis. Energy moves from producers to consumers and is eventually lost as heat.
- Primary producers capture solar energy.
- Primary consumers eat producers.
- Secondary and tertiary consumers eat other consumers.
- Decomposers break down dead matter, returning nutrients to the system.
Definition: A food chain is a linear sequence that shows how energy and nutrients move from one organism to another.
3. Nutrient Cycles
Nutrients such as carbon and nitrogen cycle between biotic and abiotic pools through processes like uptake, respiration, decomposition, and fixation.
- Carbon cycle: photosynthesis, respiration, decomposition, and storage in biomass and soils.
- Nitrogen cycle: nitrogen fixation, assimilation, ammonification, nitrification, denitrification.
Definition: Nutrient cycling is the movement and exchange of organic and inorganic matter back into the production of living matter.
Practical application
- Agricultural management uses knowledge of the nitrogen cycle to optimize fertilizer use and reduce runoff pollution.
4. Types of Ecosystems
| Type | Description | Example |
|---|---|---|
| Terrestrial | Land-based systems | Forests, grasslands, deserts, tundra |
| Aquatic - Freshwater | Low-salinity water systems | Lakes, rivers, ponds |
| Aquatic - Marine | High-salinity systems | Oceans, coral reefs |
| Artificial | Human-maintained systems | Croplands, aquariums, gardens |
5. Ecosystem Functions and Services
Ecosystems perform multiple functions that translate into services benefiting humans.
5.1 Types of ecosystem services
- Provisioning services: food, fresh water, wood, fuel, medicines.
- Regulating services: climate regulation, flood control, water purification, pollination, disease regulation.
- Cultural services: recreation, tourism, aesthetic and spiritual benefits.
- Supporting services: soil formation, nutrient cycling, primary production.
Definition: Ecosystem services are the direct and indirect contributions of ecosystems to human survival and quality of life.
Example: Wetlands
- Provisioning: fish and reeds.
- Regulating: water purification and flood attenuation.
- Cultural: birdwatching and recreation.
- Supporting: nutrient trapping and habitat for juvenile species.
6. Importance for Human Society
- Economic value: Natural goods and services
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Ecosystems Overview
Klíčová slova: Biodiversity, Ecosystems
Klíčové pojmy: Ecosystem: interacting community of biotic and abiotic components, Biotic groups: producers, consumers, decomposers, Abiotic factors: sunlight, temperature, water, inorganic nutrients, Energy flows from sunlight to producers to consumers and exits as heat, Nutrient cycles recycle carbon and nitrogen via processes like decomposition, Main ecosystem types: terrestrial, freshwater, marine, artificial, Four ecosystem services: provisioning, regulating, cultural, supporting, Natural vs human-made environments differ in origin, biodiversity, and maintenance, Wetlands provide filtration, flood control, and nursery habitats, Forests and oceans act as major carbon sinks, Human activities (urbanization, pollution) alter ecosystem functions