Page 1: Course Overview

Course Title and Module

• Environmental Science and Sustainability

• Course Code: GEOG 280

• Module #4

• Instructor: Dr. Giliane Rasbold

• Contact: giliane.rasbold@wku.edu

• Institution: WKU Department of Earth, Environmental, and Atmospheric Sciences

Page 2: Organization of the Environment (Ecology)

Definitions

Species

• A group of living organisms capable of interbreeding and exchanging genes.

Population

• A subset of individuals of one species occupying a specific geographic area.

Biological Community

• An interacting group of various species in a common location.

Page 3: Ecosystem Organization

Ecosystem Definition

• A biological community of interacting organisms and their physical environment, encompassing both biotic (living) and abiotic (non-living) factors.

Energy and Matter Flow

• Describes the flow of energy and cycling of matter among organisms and their environment.

Types of Ecosystems

• Aquatic Ecosystems: Freshwater, Marine

• Terrestrial Ecosystems

Page 4: Freshwater Aquatic Ecosystems

Abiotic Factors Affecting Life

• Water temperature

• Amount of sunlight

• Oxygen levels in water

• Nutrient availability

• Water movement

Examples of Freshwater Ecosystems

• Lakes, ponds, wetlands, rivers

Page 5: Marine Ecosystems

Abiotic Factors Affecting Life

• Light availability (photic and aphotic zones)

• Temperature

• Depth

• Distance from shore (Benthic vs. Pelagic zones)

Page 6: Wetlands

Definition

• Areas inundated or saturated by surface or groundwater, supporting vegetation adapted for life in saturated soil conditions, defined by U.S. regulations since the 1970s.

Page 7: Functions of Freshwater Wetlands

Key Functions

• Absorb and remove pollutants from water (functioning like kidneys in the landscape)

• Control flooding and stream flow rates

• Serve as nurseries for biodiversity (hotspots)

• Recreational spaces

Characteristics of Wetland Soils and Vegetation

• Hydric soils develop under anoxic conditions, noted by color and physical structure.

• Hydric vegetation adapted to substrate inundation, affected by oxygen levels.

Page 8: Types of Wetland Ecosystems

Major Types

• Swamps: Forested wetlands in tropical and temperate climates.

• Marshes: Wetlands without trees.

• Bogs: Characterized by cooler climates.

Page 9: Ecotones

Definition and Importance

• Transitional zones between distinct ecosystems.

• Higher species diversity due to the overlap of ecological niches.

Page 10: Ecosystem Services

Benefits from Ecosystems

• Provisioning Services: Food, clean water, wood, and pollination.

• Regulating Services: Climate regulation, flood control, and water purification.

• Cultural Services: Aesthetic, recreational, and educational values.

• Supporting Services: Soil formation, photosynthesis, and biodiversity maintenance.

Page 11: Landscapes

Definition

• A cluster of interacting ecosystems representing a specific geographical area.

Page 12: Biomes

Definition

• Large geographical areas classified by temperature, precipitation, and dominant vegetation types.

• Biomes share similar climate, soil conditions, and comparable communities.

Influencing Factors

• Latitude, altitude, and precipitation.

Page 13: Habitat and Niche

Habitat

• The place where a species is adapted to live based on conditions and resources.

Niche

• The role a species plays in its habitat, including food sources, reproduction, and relationships with other species

Page 14: Limiting Factors

Population Dynamics

Limiting Factors

• Operate within an optimum range, acting as environmental resistance.

Biotic Potential

• Factors that increase population, like reproductive rates and adaptations.

Environmental Resistance

• Challenges like lack of food, water, suitable habitats, predators, diseases, and competition.

Page 15: Optimum Range

Concept of Tolerance Ranges

• Describes the conditions under which a species can thrive, including physiological stress zones and intolerable conditions.

Page 16: Keystone Species

Definition

• A species on which other ecosystem members heavily depend; its removal alters the ecosystem significantly.

Types of Roles

• Predator, Prey, Ecosystem Engineer.

Page 17: Prey Role

Importance of Prey

• Serves as a critical food source for predator populations.

• Resilient and aids in maintaining predator-prey balance.

Page 18: Predator Role

Importance of Predators

• Controls prey population and range; their removal can cause a trophic cascade.

Page 19: Trophic Cascade

Ecological Events

• Top-Down: A change in predators triggers a chain reaction down the food web.

• Bottom-Up: A change at the producer level affects the entire web.

Page 20: Ecosystem Engineers

Definition and Examples

• Organisms that create or modify landscapes and influence the prevalence of other species.

• Example: Beavers create ponds that offer habitats for other species, providing protection from predators.

Page 21: Indicator Species

Importance

• Reflects environmental conditions, helping in monitoring ecological changes.

Examples

• Amphibians (e.g., frogs) indicate pollution levels due to their sensitive skin.

• Algae serve as indicators of water quality deterioration.

Page 22: Endemic Species

Definition and Examples

• Species restricted to a specific geographical area, not found elsewhere.

Examples

• Kangaroos in Australia, Lemurs in Madagascar, Poison dart frogs in Costa Rica.

Page 23: Invasive Species

Definition

• Non-native species whose introduction can cause ecological harm.

Examples

• Zebra mussels, Hydrilla, Asian Carp.

Page 24: Community Interactions - Competition

Types

• Competition: Both species harmed (- -)

• Interspecific competition (between species)

• Intraspecific competition (within species)

Page 25: Community Interactions - Predation

Definition

• One organism benefits at the expense of another (predator-prey relationship).

Example

• Lions hunting zebras helps regulate both populations.

Page 26: Community Interactions - Mutualism

Definition

• Both species benefit from the interaction.

Example

• Bees pollinating flowers while feeding on nectar.

Page 27: Community Interactions - Parasitism

Definition

• One organism benefits at the other's expense, causing harm (parasite-host relationship).

Example

• Ticks feeding on dogs.

Page 28: Community Interactions - Amensalism

Definition

• One species harmed while the other remains unaffected.

Example

• A tree shading smaller plants.

Page 29: Community Interactions - Commensalism

Definition

• One species benefits while the other is neither helped nor harmed.

Example

• Barnacles on whales.

Page 30: Reasons for Species Decline

Major Factors

• Habitat change, conversion, fragmentation, simplification.

• Overexploitation, pollution, invasive species, land management, and changing species interactions.

Page 31: Trophic Pyramid - Terrestrial System

Energy Transfer

• Follows the 10% rule: Approximately 10% of energy/biomass is passed to the next level.

Example Breakdown

• 1,000 lbs of plants (producers) -> 100 lbs of herbivores (primary consumers) -> 10 lbs of carnivores (secondary consumers).

Page 32: Trophic Pyramid - Aquatic System

Energy Dynamics

• Energy distribution may be reversed; higher trophic levels may contain more biomass than primary producers due to reproductive speed and energy efficiency.

Page 33: Bioaccumulation vs. Biomagnification

Definitions

• Bioaccumulation: Contaminant accumulation in an organism over time from various sources.

• Biomagnification: Increased toxin concentration in organisms higher up the food chain.

Page 34: Case Study: Mercury

Example

• Mercury in predatory fish is a prominent example of biomagnification, leading to health risks for humans consuming these fish.

Page 35: Disturbance and Resilience

Resilience Definition

• The ability of an ecosystem to return to normal after a disturbance.

Indicators of Resilience

• Nutrient replenishment, plant and animal dispersion, regrowth, and succession.

Page 36: Forest Ecosystems

Types

• Temperate Deciduous Forests: Characterized by hardwoods like oak and maple, found in the eastern U.S.

• Coniferous Forests: Dominant in northern states and the Pacific, featuring evergreen trees.

Page 37: Aquatic and Coastal Ecosystems

Freshwater Ecosystems

• Lakes and ponds are abundant, major river systems include the Mississippi and Colorado.

Marine Ecosystems

• Include diverse ecosystems such as kelp forests, coral reefs, and crucial wetlands in coastal areas.

Page 38: Threatened Species Overview

Examined Species

• Bighorn Sheep, Grizzly Bears, Woodland Caribou, Killer Whales, Manatees, Polar Bears, Jaguars.

Assessment Factors

1. Habitat and Location

2. Human-Induced Threats

3. Consequences and Current Status

4. Conservation Strategies