People and the Earth's Ecosystem Module PDF

People and the Earth’s Ecosystem EDNA B. BAGCAL, Ed.D; RN Foreword It is with great enthusiasm that I present this module, People and the Earth's Ecosystem, which delves into one of the most critical and timely topics of our era: the intricate relationship between humanity and the natural world....

People and the Earth’s Ecosystem EDNA B. BAGCAL, Ed.D; RN Foreword It is with great enthusiasm that I present this module, People and the Earth's Ecosystem, which delves into one of the most critical and timely topics of our era: the intricate relationship between humanity and the natural world. As we navigate an age of unprecedented environmental challenges and opportunities, understanding how human activities influence ecosystems—and how ecosystems, in turn, shape our lives—has never been more essential. This module is designed to foster a deeper appreciation for the dynamic interplay between population trends, resource management, and environmental sustainability. By exploring themes such as demographic shifts, environmental impact, and innovative policy solutions, learners will develop the knowledge and skills needed to critically engage with pressing global issues. The content within these pages is more than academic; it is a call to action. It challenges students to think critically, act responsibly, and envision a future where people and ecosystems coexist in balance. As you journey through the topics of youthful and aging populations, population growth, and the environmental challenges we face, I encourage you to reflect not only on the issues at hand but also on the roles you can play in shaping a sustainable future. This module represents an effort to illuminate the complexities of our interconnected world. May it inspire curiosity, ignite meaningful discussions, and empower you to contribute to a more harmonious relationship between people and the Earth's ecosystems. Enjoy the journey! Sincerely, Edna Espinosa Boniog-Bagcal Author January, 2025 Table of Contents Module 1. EARTH ECOSYSTEM Lesson 1. Introduction to Ecosystems - Concepts and Components Overview of ecosystems Overview of Ecosystem An ecosystem is a complex network of living organisms (plants, animals, and microorganisms) interacting with each other and their physical environment (air, water, soil, and climate) in a specific area. It represents a dynamic system where biotic (living) and abiotic (non-living) components coexist and influence one another, creating a delicate balance essential for sustaining life. Ecosystems consist of biotic and abiotic factors, which work together to create a dynamic environment that supports life. These factors are interconnected, influencing each other and determining the overall health and functionality of the ecosystem. Biotic Factors Definition Biotic factors are the living components of an ecosystem. They include all organisms that directly or indirectly interact with one another within the environment. These interactions can involve processes such as predation, competition, symbiosis, and reproduction. Examples:  Producers: Plants, algae, and photosynthetic bacteria that convert sunlight into energy, forming the base of the food chain.  Consumers: Animals that depend on producers (herbivores) or other consumers (carnivores and omnivores) for energy.  Decomposers: Fungi, bacteria, and detritivores that break down dead organic matter, recycling nutrients back into the ecosystem. Role in Ecosystems: Biotic factors drive key ecological processes such as:  Energy transfer through food chains.  Population regulation through predator-prey dynamics.  Maintenance of biodiversity and ecosystem stability. Abiotic Factors Definition: Abiotic factors are the non-living physical and chemical elements of an ecosystem. They shape the environment and influence the survival, behavior, and distribution of organisms. Examples:   Physical Factors: Sunlight, temperature, wind, water, and soil structure.  Chemical Factors: pH levels, salinity, oxygen availability, and mineral nutrients. Role in Ecosystems: Abiotic factors set the stage for life by determining:  The types of organisms that can survive in a given environment.  The productivity of ecosystems, as factors like sunlight and water availability directly affect photosynthesis.  Environmental conditions that organisms must adapt to, such as extreme temperatures or nutrient-poor soils. Interdependence Between Biotic and Abiotic Factors The interaction between biotic and abiotic factors is crucial for ecosystem functionality: 1. Abiotic factors influence biotic factors: o Availability of sunlight determines plant growth. o Soil nutrients affect plant health, which impacts herbivores and the entire food chain. 2. Biotic factors modify abiotic conditions: o Trees provide shade, altering temperature and moisture levels. o Decomposers recycle organic material, enriching the soil. The Importance of Ecosystems in Sustaining Life Ecosystems are the foundation of life on Earth, providing essential services and resources that support all living organisms. From regulating the environment to supplying the necessities of life, ecosystems play a crucial role in maintaining balance and ensuring the survival of species, including humans. 1. Provision of Essential Resources Ecosystems provide the fundamental resources needed for life, including:  Food: Croplands, forests, and aquatic systems produce food for humans and animals.  Water: Freshwater ecosystems like rivers, lakes, and wetlands are critical for drinking water, agriculture, and sanitation.  Raw Materials: Ecosystems supply wood, fibers, and other materials for construction, clothing, and industry. 2. Regulation of Environmental Conditions Ecosystems maintain environmental stability and support life by regulating key processes:  Climate Regulation: Forests and oceans absorb carbon dioxide, helping to mitigate climate change.  Water Cycle: Wetlands, forests, and soil systems regulate water flow, purify water, and prevent floods and droughts.  Air Quality: Plants produce oxygen and filter pollutants from the air.  Pollination: Bees, butterflies, and other pollinators support the reproduction of crops and wild plants. 3. Support for Biodiversity Ecosystems provide habitats that sustain a wide variety of species, fostering biodiversity, which is critical for:   Ecosystem Resilience: Diverse ecosystems are more robust and better able to recover from disturbances.  Genetic Resources: Biodiversity provides genetic material for food, medicine, and adaptation to environmental changes. 4. Cultural and Spiritual Value Ecosystems enrich human lives in non-material ways:  Recreation and Tourism: Natural landscapes attract tourism, contributing to well- being and economic growth.  Cultural Significance: Many cultures have spiritual and traditional connections to their natural environment.  Aesthetic and Educational Value: Ecosystems inspire art, literature, and scientific discovery. 5. Role in Nutrient Cycling and Energy Flow Ecosystems are essential for recycling nutrients and sustaining energy flow:  Nutrient Recycling: Decomposers break down organic matter, returning nutrients to the soil for plant growth.  Energy Flow: Ecosystems support food chains, transferring energy from producers (plants) to consumers (animals). 6. Human Well-Being and Economic Importance Healthy ecosystems underpin human health and economies:  Medicine: Many medicines are derived from plants and animals in natural ecosystems.  Economic Support: Agriculture, forestry, fisheries, and tourism rely heavily on functioning ecosystems.  Health Benefits: Natural environments promote physical and mental health, reducing stress and improving quality of life. Challenges to Ecosystems Human activities such as deforestation, pollution, and climate change threaten ecosystems, reducing their ability to sustain life. Protecting ecosystems through sustainable practices, conservation, and restoration is essential to preserve their life-supporting functions. Application: Answers in your big notebook Analyzing Ecosystem Interactions Scenario: A forest ecosystem consists of trees, herbivores like deer, predators such as wolves, and decomposers like fungi. Due to human activity, a significant number of trees are cut down. Question 1: Describe how this deforestation might affect the herbivores, predators, and decomposers in this ecosystem. Suggest measures to mitigate the negative effects. Exploring Abiotic and Biotic Factors Observe a local park or garden and identify five abiotic and five biotic components present in the environment. Explain how the abiotic factors influence the biotic components in the observed area. Lesson 2. Biotic and Abiotic Interactions in Ecosystems Types of ecological interactions Types of Ecological Interactions Ecological interactions are relationships between organisms within an ecosystem. These interactions can be categorized based on how organisms affect each other. Below are the main types of interactions. 1. Mutualism- a relationship where both species benefit from the interaction. Example: Bees and flowering plants. Bees collect nectar for food while pollinating the flowers, which helps the plants reproduce.  Illustration: A bee landing on a brightly colored flower. 2. Predation- a relationship where one organism (the predator) hunts and eats another organism (the prey). Example: Lions hunting zebras. The lion gains food, while the zebra is the prey. Illustration: A lion chasing a zebra on the savanna. 3. Parasitism- a relationship where one organism (the parasite) benefits at the expense of the host, often harming it but not killing it outright. Example: Ticks feeding on a deer. Ticks gain nourishment, while the deer may suffer from blood loss and disease. Illustration: A close-up of a tick attached to a deer's skin. 4. Commensalism- A relationship where one species benefits and the other is neither helped nor harmed.  Examples:  Illustration: 5. Competition- A relationship where two or more organisms compete for the same resources, such as food, water, or territory.  Example: Two bird species competing for nesting sites in a forest.  Illustration: Birds fighting over a nesting tree. 6. Amensalism- A relationship where one organism is harmed, and the other is unaffected.  Example: A large tree shading smaller plants, preventing them from getting sunlight.  Illustration: A tall tree casting a shadow over smaller plants struggling to grow. 7. Neutralism- A relationship where two species interact but have no significant effect on each other.  Example: A spider building its web on a tree trunk, while a bird perches on a nearby branch.  Illustration: illustration depicting neutralism, where a spider builds its web on a tree trunk and a bird perches on a branch nearby Roles of Abiotic Factors in Shaping Ecosystems Abiotic factors are the non-living components of an ecosystem that profoundly influence its structure, function, and the organisms within it. These factors provide the physical and chemical foundation for life, creating conditions that support and sustain ecosystems. Below are key roles that abiotic factors play: 1. Determining Habitat Suitability  Temperature: Governs the survival and distribution of species. For example, polar bears thrive in cold climates, while cacti are adapted to hot deserts.  Water Availability: Determines the types of organisms in an area, such as amphibians in wetlands or camels in arid regions.  Example: Coral reefs flourish in warm, shallow waters with stable salinity levels. 2. Influencing Biotic Interactions  Abiotic factors like light and soil nutrients impact plant growth, which in turn affects herbivores and predators.  Example: Nutrient-rich soil leads to dense vegetation, supporting diverse animal populations. 3. Driving Adaptation and Evolution  Organisms adapt to abiotic factors over time, leading to the evolution of traits that enhance survival.  Example: Fish in deep oceans have bioluminescent features to adapt to the absence of light. 4. Regulating Ecosystem Processes  Sunlight: Provides energy for photosynthesis, the base of most food webs.  Air: Oxygen is essential for respiration, while carbon dioxide is necessary for photosynthesis.  Water: Vital for all biochemical processes.  Example: Photosynthetic organisms rely on sunlight to produce energy, forming the basis of energy transfer in ecosystems. 5. Shaping Ecosystem Dynamics  Abiotic factors influence ecosystem productivity, stability, and resilience.  Example: Changes in rainfall patterns due to climate change can shift ecosystem types, such as turning grasslands into deserts. 6. Interactions with Biotic Factors  Abiotic and biotic factors work together to maintain ecological balance. Plants (biotic) require sunlight, water, and nutrients (abiotic) to grow.   Example: A forest ecosystem depends on soil (abiotic) to anchor trees (biotic), which provide habitats for other organisms. Key Abiotic Factors and Their Roles Abiotic Factor Role Examples Energy source for photosynthesis and Tropics have high biodiversity Sunlight temperature regulation. due to ample light. Essential for hydration, nutrient transport, Rivers support aquatic Water and habitat. ecosystems. Supplies nutrients and provides a medium Soil Fertile soil supports agriculture. for plants to grow. Determines the metabolic rates and Polar regions have specialized Temperature survival of organisms. cold-adapted species. Provides gases like oxygen and carbon Oxygen sustains animal Air dioxide necessary for life processes. respiration. Essential for plant growth and biochemical Calcium in soil strengthens Minerals processes. plant structures. Essential for hydration, nutrient transport, Rivers support aquatic Water and habitat. ecosystems. Case Studies of Specific Ecological Interactions Ecological interactions shape the structure and functioning of ecosystems, and understanding specific examples provides insight into their dynamics. Below are case studies illustrating different types of interactions: 1. Mutualism: Pollination in the Amazon Rainforest Interaction: Mutualism (both species benefit)  Case Study: In the Amazon, bees and orchids exhibit a mutualistic relationship. Bees collect nectar from orchids, which provides them with energy. In the process, they transfer pollen from one flower to another, aiding in plant reproduction.  Impact: This relationship is crucial for maintaining the biodiversity of the rainforest, as many plants depend on bees for pollination. 2. Predation: Wolves and Elk in Yellowstone National Park  Interaction: Predation (one species benefits, the other is harmed)  Case Study: The reintroduction of gray wolves to Yellowstone restored balance to the ecosystem. Wolves predate on elk, reducing overgrazing and allowing vegetation to recover, which benefits other species like beavers and songbirds.  Impact: This trophic cascade highlights the importance of predators in maintaining ecosystem health and biodiversity. 3. Parasitism: Mistletoe on Oak Trees  Interaction: Parasitism (one species benefits, the other is harmed)  Case Study: Mistletoe attaches to oak trees and extracts water and nutrients, weakening the tree. While mistletoe thrives, the host tree may suffer reduced growth and increased susceptibility to disease.  Impact: Parasitism showcases how one organism's success can negatively affect another, altering ecosystem dynamics. 4. Commensalism: Cattle Egrets and Livestock  Interaction: Commensalism (one species benefits, the other is unaffected)  Case Study: Cattle egrets feed on insects stirred up by grazing cattle. The egrets gain food, while the cattle remain unaffected.  Impact: This interaction illustrates how one species can benefit from the behavior of another without influencing it. 5. Competition: Lions and Hyenas in the African Savannah  Interaction: Competition (both species are harmed)  Case Study: Lions and hyenas compete for food resources in the savannah. Both species hunt similar prey, and direct confrontations often occur over kills.  Impact: Competition limits the availability of resources, driving adaptations like hunting strategies and territorial behavior. 6. Amensalism: Allelopathy in Black Walnut Trees  Interaction: Amensalism (one species is harmed, the other is unaffected)  Case Study: Black walnut trees release chemicals into the soil that inhibit the growth of nearby plants. The tree remains unaffected, but neighboring plants struggle to survive.  Impact: Allelopathy demonstrates how some species indirectly suppress others, influencing plant community composition. 7. Neutralism: Spiders and Frogs Sharing a Habitat  Interaction: Neutralism (neither species affects the other significantly)  Case Study: In a tropical forest, spiders build webs in trees, while frogs reside in the same area. They coexist without interacting significantly.  Impact: Neutralism highlights coexistence without direct ecological influence, emphasizing the complexity of ecosystems. Case studies provide concrete examples to understand these interactions' real-world implications, emphasizing the interconnectedness of living and non-living components in ecosystems. Application: 1. Explain how sunlight (an abiotic factor) influences biotic factors in an ecosystem. _____________________________________________________________________ _____________________________________________________________________ ________________________________________________________________ 2. Describe the interaction between soil (abiotic) and plants (biotic) in an ecosystem. _______________________________________________________________ _______________________________________________________________ _______________________________________________________________ 3. How does temperature (abiotic) affect the distribution of animal species (biotic) in an ecosystem? _____________________________________________________________________ _____________________________________________________________________ ________________________________________________________________