REVIEWER SIYA SA ES

CHAPTER 1: THE ECOLOGICAL FOUNDATIONS OF ENVIRONMENTAL SCIENCE

Environment

• Definition: Circumstances or conditions that encircle or surround an organism or group of organisms.

• Includes complex social and cultural conditions impacting individuals or communities.

Ecosystem

• Fundamental concept in ecology.

• Comprises organisms, populations, and communities that influence one another.

• A combination of a community and physical factors of the nonliving environment.

• Represents a dynamic network of interactions among biological, chemical, and physical elements.

• Defined by obligatory relationships and interdependence among habitats and niches.

• Arthur Tansley: Recognized as the father of ecosystem.

Key Ecosystem Components

• Ecology: The study of systems involving individual organisms or populations.

• Population: Group of the same kind of organisms in a specific location (e.g., all milkfish in a lake).

• Organism: Any living entity made of one or more cells, capable of growth and reproduction.

• Habitat: Natural living place of an organism, fulfilling a niche within its ecosystem.

• Biotic Community: Interaction of several populations of different species in a specific area (e.g., plants and animals in a forest).

• Biosphere: Unique ecosystem with defined material boundaries, minimal material exchange with the external environment.

• Ecosystem Structure: The arrangement of functional elements within a habitat and their interrelationships.

Page 2: Components of Ecosystem

Two Components:

1. Abiotic (Non-living) Components:

   • Serve as life support systems and can regulate physical conditions.

   • Act as limiting factors controlling plant/animal populations.

2. Biotic (Living) Components:

   • Represents species richness in a given area.

   • Trophic Structure: Food relationships defined by nutritional habits of organisms.

     • Producers (Autotrophs): Create their own organic compounds for energy.

       • Photosynthesis: Conversion of sunlight into chemical energy.

       • Chemosynthesis: Conversion of inorganic compounds into organic nutrients without sunlight.

     • Consumers (Heterotrophs): Obtain energy by consuming other organisms:

       • Primary Consumers: Herbivores feeding on plants.

       • Secondary Consumers: Carnivores feeding on herbivores.

       • Tertiary Consumers: Larger carnivores or omnivores feeding on others.

     • Decomposers: Break down dead organic matter:

       • Detritivores (e.g., crabs, earthworms): Ingest dead matter.

       • Decomposers (e.g., bacteria, fungi): Absorb soluble nutrients at the cellular level.

Page 3: Ecosystem Functions

Main Functions:

1. Production: Building organic structures from nonliving materials.

2. Decomposition: Breakdown of organic structures.

3. Consumption: Creation of organic structures in consumers using digested food.

   • Cellular Respiration: Releases energy from chemical bonds within cells.

Energy Flow in Ecosystem

• Governed by the Laws of Thermodynamics:

  1. Conservation of Energy: Energy cannot be created or destroyed, only transformed.

  2. Degradation of Energy Quality: Energy transfers are less organized and dispersed with each change.

Food Relationships:

• Food Chain: Transfer of energy from one organism to another (e.g., plants to herbivores).

  • Significant energy loss (80-90%) at each transfer.

• Food Web: Complex interconnections among multiple food chains.

Measures of Energy Flow:

• Pyramid of Energy: Shows energy decrease at each trophic level (only 10% captured).

• Pyramid of Biomass: Total dry weight of living matter at each level.

• Pyramid of Numbers: Number of organisms at each level.

Page 4: Biogeochemical Cycles

Nutrient Cycles:

1. Hydrologic Cycle: Water collection, purification, and distribution, including:

   • Evaporation: Water to vapor.

   • Condensation: Vapor to water droplets.

   • Transpiration: Water vapor from plants.

   • Precipitation: Rain, snow, etc.

   • Runoff: Water draining back to the sea.

2. Carbon Cycle: Transformation of carbon through various processes:

   • Photosynthesis: Converts CO2 into organic compounds.

   • Respiration: Returns carbon to the atmosphere.

   • Decomposition: Breaks down organic matter, returning carbon.

   • Fossil Fuel: Formation and combustion of carbon deposits.

3. Nitrogen Cycle: Involves microbial processes to convert nitrogen:

   • Nitrogen Fixation: Conversion of atmospheric nitrogen to usable forms.

   • Ammonification: Decomposition transforming waste to ammonia.

   • Nitrification: Conversion of ammonia to nitrates by bacteria.

   • Denitrification: Bacteria returning nitrogen to the atmosphere.

Phosphorus Cycle

• Phosphorus sourced from weathering and erosion, absorbed by plants, consumed by animals, and returned to sediments through decomposition or geological uplift.

Page 5: CHAPTER 2: ECOSYSTEM TYPES AND BIOMES

Ecological Succession

• Process by which species composition evolves over time.

• Primary Succession: Colonization of barren land by biological entities (pioneer species to climax community).

• Secondary Succession: Re-establishment after disturbances (like fire or flood).

Types of Ecosystems

• Natural Ecosystems: Formed naturally and regenerated through natural processes.

• Man-Made Ecosystems: Human-created and maintained systems, such as:

  • Natural Ecosystems: Aquatic (marine, estuarine, freshwater) and terrestrial (forest, desert, grassland).

  • Terrestrial Ecosystems include:

    • Forest: Dense vegetation with abundant rainfall (80-400 cm).

    • Desert: Very low rainfall (<25 cm) with minimal vegetation.

    • Grassland: Dominated by grasses with moderate rainfall (25-75 cm).

Aquatic Ecosystems

• Freshwater Ecosystems: Rivers, lakes offering water sources for life.

  • Riverine Ecosystems: Fast-moving waters of streams and rivers.

  • Lacustrine Ecosystems: Still waters (lakes).

  • Palustrine Ecosystems: Wetlands with prolonged saturated soils.

• Marine Ecosystem: Covers 71% of Earth, consisting of coastlines, open sea, and ocean floors.

Page 6: Biomes

Terrestrial Biomes

• Tundra: Cold climate, lacks complex flora/fauna, permafrost present.

• Taiga: Largest biome, northern coniferous forest, needleleaf trees.

• Desert: Driest biome, sustains limited life due to extreme conditions.

• Grassland: Dominated by grasses, moderate precipitation.

• Temperate Forest: Deciduous trees and changing seasons.

• Rainforest: High species diversity compared to other biomes.

Aquatic Biomes

• Marine Biomes: Plankton-rich, varying depths influence biological communities.

• Estuaries: Nutrient-rich areas where freshwater meets saltwater.

• Freshwater Biomes: Variety of water bodies support diverse life forms.

Page 7: Ecological Successions

• Marshes, Swamps, Bogs: Types of palustrine wetlands with unique hydrophytic plants.

Page 8: CHAPTER 3: UNIFYING THEMES IN ENVIRONMENTAL SCIENCE

Economic Activities

• Categories:

  • Production, Distribution, Consumption, Investment, Trade.

Environment

• Natural Resources: Raw materials necessary for survival.

• Sustainable Economy: Utilizes resources responsibly within planetary limits.

• Green Economy: Achieves sustainable practices.

Wastes D:

• Defects, Over Production, Waiting Time, Non-Utilized Talent, Transportation, Inventory, Motion, Extra Processing.

Sustainable Consumption and Production (SCP)

• Sustainable Resource Management, Design for Sustainability (D4S), Cleaner Production, Sustainable Transport, Eco-labelling, Sustainable Procurement, Marketing, Lifestyle, Waste Management.

Environmental Movement

• Objective: Protect natural resources for sustainability.

• Environmentalism: Focus on protecting the environment, conserving resources, promoting sustainability.

• Key Emphasis Areas: Sustainability, Conservation, Pollution Control, Climate Action, Environmental Justice.

Page 9: Environmental Policies

• RA 8749: Clean Air Act defines commitment to environmental management.

Major Environmental Problems

• Biodiversity, Air and Water Pollution, Food Supply Issues, Waste Production.

Fundamental Principles

1. Sustainability Principles: Maintain ecological health for life support.

2. Polluter Pays Principles: Fairness and responsibility in trade.

3. Precautionary Principles: Prevent harm through assessments.

4. Participation Principles: Involve public in decision-making.

5. Equity Principles: Justice for future generations.

6. Human Rights Principles: Align environmental policies with human rights.

Three Unifying Themes

1. Sustainability: Defining limits to resource exploitation.

2. Sound Science: Grounding environmental issues in factual research.

3. Stewardship: Arranging protection through recycling and conservation.

Stewardship Roles

• Doers: Individuals solving environmental issues.

• Donors: Financial supporters of initiatives.

• Practitioners: Scientists, policy officers, and environmental group staff.