Quiz Questions | Ecological Resilience

Quiz

Question

Ecological resilience is the amount of disturbance an ecosystem can absorb before altering ________.

Self-organized processes and structures

This is correct. A system is made up of components that form a larger structure, with processes and interactions arising organically between components. Resilience encompasses the ability of that structure and its processes to persist despite pressures to change.

Types of disturbance

This is incorrect. Resilience is not defined by what type of disturbance the system undergoes, but rather how the system handles any kind of disturbance.

Soil types

This is incorrect. Soil types may be a component of a system, but soil alone does not account for all the complex interactions occurring between the parts of a system.

Hysteresis

This is incorrect. Hysteresis is broadly defined as, “the way out is different from the way in,” meaning that a system may change one way, but to reverse the change a different path must be taken.

Looks Good! This is correct. A system is made up of components that form a larger structure, with processes and interactions arising organically between components. Resilience encompasses the ability of that structure and its processes to persist despite pressures to change.

Question

Ecological resilience originated by C.S. Holling is the idea that ________.

Ecosystems oscillate between healthy and unhealthy over time.

This is incorrect. Ecosystems may cycle between states or remain in one state forever until a disturbance forces it to change state. However, healthy and unhealthy are descriptors that are arbitrarily assigned from a human perspective and do not accurately represent an ecosystem.

Ecosystems undergo sudden and discontinuous change following a disturbance that cannot be absorbed.

This is correct. Ecological resilience as described by Holling aims to understand the capacity of an ecosystem to absorb disturbances and persist, along with the sudden change in state that may occur if absorbance and persistence are overcome.

Ecosystems at their peak do not undergo long-term change since they can absorb disturbance and remain in optimal condition forever.

This is incorrect. Even an ecosystem at its peak, called the “climax community,” may encounter a disturbance strong enough to force it to change its state.

Ecosystems may undergo short-term change but will always return to their original state if left alone.

This is incorrect. Ecosystems are not “programmed” to return to a specific single state over time. If pushed by some sort of disturbance or change in parameters, the ecosystem may change into an alternative state.

Looks Good! This is correct. Ecological resilience as described by Holling aims to understand the capacity of an ecosystem to absorb disturbances and persist, along with the sudden change in state that may occur if absorbance and persistence are overcome.

Question

From the ball-in-cup model, what are the two paths a system may take to change states?

Regimes 1 and 2 are the basins of attraction.

This is incorrect. While the basins of attraction are part of the ball-in-cup model, they are not the way a system changes states

Thresholds and alternative stable states.

This is incorrect. These are part of the ball-in-cup model but they are not the way a system changes states.

Internal change within the system and external change outside the system.

This is correct. The system may undergo internal changes, or be made to change from outside forces. The outcome is the same, the system leaves its old cup and moves into a new one.

The way out is different from the way in.

This is incorrect. This is the definition of hysteresis. It means that a system may change state with a certain level of inputs, but to reverse the change and return back to the original state an extra level of inputs must be removed.

Looks Good! This is correct. The system may undergo internal changes, or be made to change from outside forces. The outcome is the same, the system leaves its old cup and moves into a new one.

Question

Ecological resilience can be applied to the management of ecosystems because ________.

There is a balance of nature.

This is incorrect. Nature does not balance at a peak ecosystem. Conditions are always changing and disturbances often throw off any balance.

Ecosystems are always predictable.

This is incorrect. Ecosystems may be very unpredictable especially when faced with novel circumstances.

Ecosystems must be fully understood so that humans will not have any impacts on them.

This is incorrect. The impacts of humans are part of an ecosystem, not apart from it. Humans are just another component of a larger structure and we interact in complex ways with other components in the system.

It helps us understand the complexity and dynamics of self-organizing systems as they absorb change or change states.

This is correct. Modelling and quantifying the complexity of systems as they change can inform managers on which changes have desired or undesired outcomes. This way we can interact with other components in the system in an efficient and positive way.

Looks Good! This is correct. Modelling and quantifying the complexity of systems as they change can inform managers on which changes have desired or undesired outcomes. This way we can interact with other components in the system in an efficient and positive way.