CR Biology B Module 1 Lesson 1

Forest Ecosystem Overview

• Forest ecosystems include a diverse range of organisms beyond just visible fauna like deer, rabbits, and insects.
• Both biotic (living) and abiotic (non-living) factors contribute to the ecosystem's structure; biotic factors include plants, animals, bacteria, and fungi, while abiotic factors encompass sunlight, soil, temperature, and water.

Ecology and Ecosystems

• Ecology studies interactions between living organisms and their environments, collaborating with fields such as geography and climatology.
• An ecosystem comprises all biotic and abiotic components within an area and their interactions, varying in scale from large lakes to decomposing logs.

Energy Flow in Ecosystems

• Ecosystems require constant energy inputs, mainly originating from sunlight, utilized through photosynthesis by producers.
• Energy flows from producers (like plants) through herbivores and then carnivores, creating a food chain.
• Unlike energy, matter (water, carbon, nitrogen) is recycled within ecosystems, showcasing the importance of nutrient cycling.

Niche and Habitat

• A niche defines the role of a species within its ecosystem, including its food sources and feeding methods.
• Habitats are determined by abiotic factors, influencing the living organisms adapted to those conditions.

Competitive Exclusion Principle

• No two species can occupy the same niche in the same habitat indefinitely due to competition for resources; this principle drives evolutionary changes.
• Character displacement occurs when species adapt to different niches over generations to reduce competition.

Photosynthesis and Energy Conversion

• Photosynthesis is critical for converting sunlight into chemical energy, underpinning the ecosystem's energy dynamics.
• Producers (autotrophs) synthesize food using inorganic molecules; they include photoautotrophs (plants, algae) and chemoautotrophs (certain bacteria).

Types of Organisms in Ecosystems

• Consumers (heterotrophs) depend on other organisms for energy, including:
  • Herbivores: E.g., deer and rabbits, consume producers.
  • Carnivores: E.g., hawks and lions, eat other animals.
  • Omnivores: E.g., humans and bears, consume both plants and animals.
• Decomposers break down dead organisms and waste, returning nutrients to the ecosystem, classified as:
  • Scavengers: E.g., vultures and raccoons, consume soft tissues of dead animals.
  • Detritivores: E.g., earthworms and sea cucumbers, feed on organic debris.
  • Saprotrophs: E.g., fungi and bacteria, complete the decomposition process.

Role of Decomposers

• Decomposers are crucial for nutrient recycling, preventing nutrient depletion in ecosystems.
• The Pacific Banana Slug is highlighted as an essential decomposer in California's old-growth redwood forests, recycling organic matter and enriching soil.

Ecosystem Interactions

• Energy and nutrient flow demonstrate the complex interactions between biotic and abiotic factors.
• Ecosystems are characterized by their producers, consumers, and decomposers, each playing a vital role in sustaining life processes within the environment.

Forest Ecosystem Overview

• Forest ecosystems include a diverse range of organisms beyond just visible fauna like deer, rabbits, and insects.
• Both biotic (living) and abiotic (non-living) factors contribute to the ecosystem's structure; biotic factors include plants, animals, bacteria, and fungi, while abiotic factors encompass sunlight, soil, temperature, and water.

Ecology and Ecosystems

• Ecology studies interactions between living organisms and their environments, collaborating with fields such as geography and climatology.
• An ecosystem comprises all biotic and abiotic components within an area and their interactions, varying in scale from large lakes to decomposing logs.

Energy Flow in Ecosystems

• Ecosystems require constant energy inputs, mainly originating from sunlight, utilized through photosynthesis by producers.
• Energy flows from producers (like plants) through herbivores and then carnivores, creating a food chain.
• Unlike energy, matter (water, carbon, nitrogen) is recycled within ecosystems, showcasing the importance of nutrient cycling.

Niche and Habitat

• A niche defines the role of a species within its ecosystem, including its food sources and feeding methods.
• Habitats are determined by abiotic factors, influencing the living organisms adapted to those conditions.

Competitive Exclusion Principle

• No two species can occupy the same niche in the same habitat indefinitely due to competition for resources; this principle drives evolutionary changes.
• Character displacement occurs when species adapt to different niches over generations to reduce competition.

Photosynthesis and Energy Conversion

• Photosynthesis is critical for converting sunlight into chemical energy, underpinning the ecosystem's energy dynamics.
• Producers (autotrophs) synthesize food using inorganic molecules; they include photoautotrophs (plants, algae) and chemoautotrophs (certain bacteria).

Types of Organisms in Ecosystems

• Consumers (heterotrophs) depend on other organisms for energy, including:
  • Herbivores: E.g., deer and rabbits, consume producers.
  • Carnivores: E.g., hawks and lions, eat other animals.
  • Omnivores: E.g., humans and bears, consume both plants and animals.
• Decomposers break down dead organisms and waste, returning nutrients to the ecosystem, classified as:
  • Scavengers: E.g., vultures and raccoons, consume soft tissues of dead animals.
  • Detritivores: E.g., earthworms and sea cucumbers, feed on organic debris.
  • Saprotrophs: E.g., fungi and bacteria, complete the decomposition process.

Role of Decomposers

• Decomposers are crucial for nutrient recycling, preventing nutrient depletion in ecosystems.
• The Pacific Banana Slug is highlighted as an essential decomposer in California's old-growth redwood forests, recycling organic matter and enriching soil.

Ecosystem Interactions

• Energy and nutrient flow demonstrate the complex interactions between biotic and abiotic factors.
• Ecosystems are characterized by their producers, consumers, and decomposers, each playing a vital role in sustaining life processes within the environment.

Explore the intricate relationships within forest ecosystems in this quiz. Discover various organisms, from visible animals like deer and rabbits to the hidden bacteria and fungi that play crucial roles in their environment. Understand how these living things interact with nonliving elements such as water.