Ecology and Ecosystems Quiz

The Biosphere as a Closed System

• Earth is a closed system, meaning matter is not exchanged with its surroundings, but energy is exchanged.
• All living things interact with each other and non-living things on Earth.
• The biosphere is a narrow zone around Earth with life.
• It has three zones: lithosphere (land), hydrosphere (water), and atmosphere (air).
• The upper atmosphere and Earth's crust affect living organisms, even though they aren't part of the biosphere.
• There are interconnectedness and complexities in nature.

Outcomes

• Explain the structure of ecosystem trophic levels (using food chains and food webs).
• Define species, population, community, and ecosystem.
• Explain interrelationships among these entities.
• Explain how terrestrial and aquatic ecosystems support diversity through habitats and niches.
• Identify biotic and abiotic characteristics and explain their influence in ecosystems (local region).

The Biosphere

• The biosphere is the narrow zone around Earth with life.
• Within the biosphere are three key zones: land (lithosphere), water (hydrosphere), and air (atmosphere).
• Even though the upper atmosphere and Earth's crust are outside the biosphere, they still influence living organisms.

Nature is Full of Interconnections and Complexities/Ecosystem Dynamics

• Earth is a complex system where all components are interconnected
• A closed system does not exchange matter with surroundings, but does exchange energy with its surroundings
• Living things are connected to each other and to nonliving components, like air, water, soil, and sunlight.

Ecosystem Dynamics (Simplified Scheme)

• Energy flows from the sun.
• Organisms use energy and cycle matter.
• Materials ultimately return to the environment and cycle back to producers (Plants and Algae)

Dynamic Equilibrium

• Every part of Earth's environment must be in balance with everything else
• Dynamic equilibrium occurs when components of a system adjust to constant changes without disturbing the entire system
• If something within an ecosystem changes, something else can adjust to avoid unbalancing the entire system
• Today, Earth's equilibrium is being affected by human activities

Biodiversity

• Biodiversity is the number of species within an ecosystem.
• The more biodiversity within an ecosystem, the more resistant or immune it is to collapse.
• Extinction of species can create a domino effect that can collapse the entire food chain within an ecosystem because they are connected.

Food Chains

• A food chain is a sequence of organisms that feed on each other through the ecosystem.
• Producers are the organisms that create their own food using the sun's energy and nutrients in the soil/water. (Plants and algae)
• Consumers are organisms that rely on producers (Herbivores) or other living organisms (Carnivores) for food.
• Decomposers, like fungi and bacteria, break down waste and dead organisms, recycling the nutrients back into the ecosystem.

Interconnectedness

• Studying interconnectedness is crucial to understanding ecosystems.
• For example, the effects of hunting otters almost to extinction and their uneven recovery demonstrated the interconnectedness of different species and their impact on the ocean ecosystem (e.g. kelp forests)

Biomagnification

• Biomagnification is a process where substances increase in concentration at higher levels within a food web.
• Toxins enter food webs via producers, and the concentration of these toxins increases as they move through the higher levels of the food web, meaning that top-level consumers are particularly affected.

Species at Risk

• More than 450 species of plants and animals are at various degrees of risk in Canada.
• Species at risk can be categorized as Extinct, Endangered, Threatened, or Special Concern. -These categories encompass the level of risk associated with each species.
  • Specific examples (e.g., Black-footed ferret, Woodland Caribou) of species at risk are provided.

Indicator Species

• Indicator species are very sensitive to small environmental changes
• They provide an early warning system about ecosystem balance
• Amphibians, for example, are indicator species, as their eggs and tadpoles live in water, and their adult forms in the forest, making them susceptible to hazards in both

Why are Amphibians Disappearing?

• Amphibians have been around for over 400 million years.
• Losses in their population are due to environmental disturbances like habitat loss, changing air and water quality, climate change, and ultraviolet radiation.

Loss of Habitat

• Frogs, specifically, require wetlands, ponds, and lakes with clean water to breed and lay eggs, and adults need a place to catch insects in fields or forests.
• They also need safe passage between these areas.
• Human activities impacting wetlands, ponds, and lakes cause losses of these habitats.

Extinction Rates

• Current extinction rates are significantly higher than natural, historical rates
• The current extinction crisis is mainly caused by humans' activities and global warming from increased CO2

Air and Water Quality

• Air and water pollutants, such as acid rain, affect frog reproduction

Air Pollution

• Air pollution, quantified by PM2.5 levels, varies across different cities.
• Higher PM2.5 levels indicate more severe air pollution.

Climate Change

• Increasing temperatures and fossil fuel usage are linked,
• Changing climate conditions result in drying climates, impacting frog populations.

Umbrella Species

• A conservation strategy for making conservation decisions that protect many other species indirectly.

Additional Information

• The image of a frog in a pot of water on fire implies the importance of acting to preserve biodiversity, highlighting that seemingly slow changes in environmental conditions may affect species.

• The image of a crossroads suggests the need to choose a better path for a better future, implying the impact humans have on the planet and decision-making for a sustainable future.

• The image of buildings with green roofs, solar panels, and wind turbines showcases examples of environmentally friendly solutions.

Test your knowledge on the crucial roles of decomposers, the impact of species decline on ecosystems, and the factors influencing biodiversity. This quiz covers various concepts related to ecology, including dynamic equilibrium, biotic and abiotic factors, and the zones of the biosphere.