Anthropogenic Impacts on Marine benthos

Question 1

What are the main human uses of the ocean that are rapidly growing?

Answer 1

Food, energy, materials, and space.

Question 2

What is the consensus about human impacts on the ocean?

Answer 2

Human impacts are increasing in intensity and extent.

Question 3

What is a stressor in a marine ecosystem?

Answer 3

Any physical, chemical, or biological factor requiring organisms to adapt or compensate.

Question 4

What are the types of stressors?

Answer 4

Local, regional, global; pulse (short-term) and press (long-term) events.

Question 5

How can stressors interact?

Answer 5

Additive (sum of effects), synergistic (greater than sum), antagonistic (less than sum).

Question 6

Why are synergistic stressor interactions challenging?

Answer 6

They worsen damage unpredictably, making management harder.

Question 7

What are sub-lethal effects, and why are they important?

Answer 7

Non-fatal changes (e.g., behavior) that still significantly impact ecosystems.

Question 8

What are the major categories of human-caused stressors?

Answer 8

Pollution, unsustainable resource exploitation, habitat destruction, invasive species, climate change.

Question 9

What did Halpern et al. (2008) achieve?

Answer 9

Created a global map of human impacts using 17 datasets.

Question 10

What was a key finding of the Halpern study?

Answer 10

No part of the ocean remains unaffected by human influence.

Question 11

What percentage of the ocean is heavily impacted by multiple stressors?

Answer 11

About 41%.

Question 12

Which ocean regions are least impacted?

Answer 12

Polar regions and remote areas.

Question 13

What criticisms were raised about the study?

Answer 13

Methodology concerns (Heath 2008); however, overall conclusions were defended (Selkoe et al. 2008).

Question 14

How did Seaspiracy (2021) impact public awareness of these issues?

Answer 14

Popularized concerns but sometimes oversimplified scientific findings.

Question 15

What is the ‘Blue Acceleration’?

Answer 15

Rapid and intensifying human use of ocean space and resources (Jouffray et al., 2019).

Question 16

Between 2008–2013, by how much did human impact increase in marine waters and national zones?

Answer 16

66% globally, 77% in national waters.

Question 17

What are the main drivers of the Blue Acceleration?

Answer 17

Climate change, resource extraction, and pollution.

Question 18

What did Thomas Huxley (1883) famously say about fish stocks?

Answer 18

Herring stocks were ‘inexhaustible’ with then-current technology.

Question 19

What is ‘shifting baselines syndrome’?

Answer 19

Each generation accepts a more degraded environment as ‘normal’ (Pauly 1995).

Question 20

How does bottom trawling affect benthic habitats?

Answer 20

Disrupts sediments, destroys structures like coral and sponges, reduces biodiversity.

Question 21

What are the impacts of deep-sea mining?

Answer 21

Disturbs sediments massively, causing long-term ecosystem damage.

Question 22

What are the impacts of marine diamond mining?

Answer 22

Alters sediment structure and ecosystem function; conservation corridors recommended.

Question 23

What happened with radioactive waste dumping in the ocean?

Answer 23

Dumped (1949–1982) into the North Atlantic, raising long-term bioaccumulation concerns.

Question 24

How did radioactive fallout from Chernobyl affect the ocean?

Answer 24

Particles reached Arctic abyssal waters within a year.

Question 25

What was the effect of sewage dumping at Deepwater Municipal Dump Site 106?

Answer 25

Sewage entered deep-sea food webs, contaminating species like sea cucumbers and urchins.

Question 26

What causes nutrient loading in coastal and estuarine systems?

Answer 26

Excess nitrogen and phosphorus from human sources.

Question 27

How does nutrient loading lead to hypoxia?

Answer 27

Stimulates algae blooms, disrupts nitrogen cycles, causing oxygen depletion.

Question 28

What are the effects of hypoxia on marine life?

Answer 28

Reduces survival, growth, behavior, and reshapes benthic communities.

Question 29

Give an example of a nutrient-loading event.

Answer 29

The massive algal bloom in Qingdao, China (2008).

Question 30

How do shipwrecks impact marine environments?

Answer 30

Release oil, heavy metals, and other toxins over time.

Question 31

How do offshore structures like oil rigs and wind farms affect ecosystems?

Answer 31

Act as artificial reefs, increase biodiversity, and create fishing refuges.

Question 32

What environmental effects come from cables and pipelines?

Answer 32

Localized heating (>100°C) and electromagnetic field emissions.

Question 33

How has human activity changed ocean soundscapes?

Answer 33

Added intense continuous (shipping) and impulsive (construction) noise.

Question 34

How does noise impact benthic species?

Answer 34

Alters behavior, bioturbation, and fitness.

Question 35

How do chemicals and pharmaceuticals enter marine organisms?

Answer 35

Ingestion, gill/skin absorption, diffusion.

Question 36

What are the sources of aquatic pharmaceutical contamination?

Answer 36

Livestock farming and human waste.

Question 37

How is CO₂ proposed to be stored in oceans?

Answer 37

Injected into sediments where it can remain trapped for >500 years.

Question 38

How does CO₂ exposure affect benthic species?

Answer 38

Increases mortality rates and decreases size/volume of organisms.

Question 39

What are pressure pathways in marine impacts?

Answer 39

Links between human sectors (fishing, mining) and ecosystem pressures.

Question 40

Why is understanding sector-pressure-impact networks important?

Answer 40

It helps design better marine management strategies.

Question 41

What is the Planetary Boundaries concept?

Answer 41

Defines a 'safe operating space' for Earth's systems based on Holocene data.

Question 42

Which boundaries have already been exceeded?

Answer 42

Climate change, biodiversity loss, and nitrogen cycle disruption.

Question 43

What are 'Seeds of a Good Anthropocene'?

Answer 43

Positive examples ('hope spots') of sustainable human–nature relationships.

Question 44

What are nature-based solutions in marine management?

Answer 44

Strategies using ecosystem processes to benefit both nature and society.

Question 45

What are benthic solutions, and why are they important?

Answer 45

Emerging methods to promote resilience and adaptation of benthic ecosystems.