Biodiversity And Ecosystem Functioning

Question 1

What is BEF research?

Answer 1

Study of how biodiversity (species richness/composition) influences ecosystem processes (productivity, nutrient cycling, stability).

Question 2

How did the 1990s change views on biodiversity?

Answer 2

Shift from seeing biodiversity as environmentally determined to recognizing it as a driver of ecosystem function.

Question 3

Why was early BEF research controversial?

Answer 3

Some misinterpreted it as challenging abiotic controls (e.g., climate), but it complements them.

Question 4

Name two landmark BEF syntheses.

Answer 4

Cardinale et al. (2012, Nature); Loreau et al. (2001, Science).

Question 5

How does complementarity enhance ecosystem function?

Answer 5

Species partition niches (e.g., root depths) or facilitate each other (e.g., nitrogen fixers).

Question 6

Why do diverse communities often outperform monocultures?

Answer 6

Higher chance of including a ‘high-performing’ species (e.g., fast-growing plant).

Question 7

Give an example from marine systems.

Answer 7

Deep-sea sea cucumbers divide food by pigment, reducing competition.

Question 8

What did the 11-year experiment demonstrate?

Answer 8

Diverse plots resisted drought better and recovered faster (higher resilience).

Question 9

What were two limitations of early BEF experiments?

Answer 9

(1) Tested few species (≤16); (2) Ignored multi-trophic interactions.

Question 10

How did the Jena Experiment address critiques?

Answer 10

500 plots with 1–60 plant species; showed complementarity dominated in mature systems.

Question 11

Why is Ythan Estuary a model BEF system?

Answer 11

Compact (8 km), shows bioturbation’s role in nutrient cycling.

Question 12

How was BPc (Bioturbation Potential) calculated?

Answer 12

Combined species abundance, biomass, mobility, and feeding traits.

Question 13

Contrast marine and terrestrial BEF patterns.

Answer 13

Marine: Small bioturbators drive large processes; Terrestrial: Plant diversity dominates.

Question 14

How does BEF support polycultures?

Answer 14

20–30% higher productivity; better resource use (e.g., nitrogen retention).

Question 15

What were the key findings of the Climate Change Experiment?

Answer 15

Richness boosted function, but high CO₂ + 18°C caused collapse, even with diversity.

Question 16

How does current extinction loss compare to background rates?

Answer 16

~1,000x faster (1 species/20 mins; 27,000/year).

Question 17

Why is random extinction loss unrealistic?

Answer 17

Specialists/large species disappear first (e.g., elephants, deep-sea corals).

Question 18

What did Bracken’s Seaweed Study show about species combinations?

Answer 18

Some experimentally possible mixes don’t occur naturally.

Question 19

Why does function plateau at high richness?

Answer 19

Niche overlap reduces unique contributions (e.g., >10 plants add minimal nitrate retention).

Question 20

Quantify marine bioturbation’s global impact.

Answer 20

30,000 km³ sediment mixed daily (~12.5x Everest’s volume).

Question 21

How can BEF guide conservation policy for protected areas?

Answer 21

Prioritize functionally unique species (e.g., keystone engineers like beavers).

Question 22

What’s a BEF-based restoration strategy?

Answer 22

Use diverse seed mixes to enhance resilience (e.g., Minnesota grasslands).

Question 23

How is BEF applied in offshore wind farms?

Answer 23

Assess impacts on benthic communities to minimize bioturbation loss.

Question 24

Give a BEF example in urban ecosystems.

Answer 24

Diverse green roofs improve stormwater retention and cooling.

Question 25

Name two emerging BEF frontiers for future research.

Answer 25

(1) Multi-trophic networks; (2) Biodiversity-climate feedbacks.

Question 26

If richness explains 59% of mixing depth and pollution 31%, why isn’t the total 90%?

Answer 26

Non-additive effects—pollution alters which species survive (e.g., sensitive bioturbators die).

Question 27

How is BEF like an ANOVA?

Answer 27

Function = richness + environment + interactions (some factors dominate, e.g., richness > CO₂).

Question 28

Why are elephants a BEF concern?

Answer 28

Loss collapses seed dispersal, nutrient cycling, and habitat structure.

Question 29

When does identity outweigh richness in functional traits?

Answer 29

If key species are present (e.g., Corophium shrimp in mudflats).

Question 30

What’s a 'zone of collapse' in BEF?

Answer 30

Critical biodiversity loss tipping points (e.g., 18°C in climate experiments).

Question 31

How does species richness changing with area (SAR) affect ecosystem function

Answer 31

Bigger Area = More Species Classic SAR: Larger habitats support more species (e.g., islands vs. continents). BEF Link: More species → higher chance of key functional species (selection effect) or better niche partitioning (complementarity). Fragmentation = Trouble Small/fragmented areas lose species faster → ecosystem functions decline (e.g., less bioturbation in tiny estuaries). Real-World Example: Minnesota grasslands: Larger plots had more plant species → higher drought resilience.

Question 32

What effect does biodiversity have on ecosystem functions?

Answer 32

Resources used more efficiently and systems more productive and stable.

Question 33

What is the selection effect?

Answer 33

Dominance by species with particular traits affects ecosystem processes. Few dominant species alone can provide the same level of function as more diverse communities.

Question 34

What is the complementary effect?

Answer 34

Resource partitioning or positive interactions lead to increased total resource use. Species complement and facilitate each other in chemical, spatial and temporal resource use.

Question 35

At lower biodiversity, is there more or less error?

Answer 35

At low biodiversity, there is more error and less certainty.

Question 36

What are criticisms of biodiversity - ecosystem function laboratory experiments?

Answer 36

Highly controlled, few species, random species loss, small spatial and temporal scales, homogenous, reduced species interactions, typically single drivers.

Question 37

What are pros of biodiversity - ecosystem function natural system experiments?

Answer 37

Highly dynamic, many species, ordered species loss, large spatial and temporal scales, heterogeneous, strong species interactions, always multiple drivers.

Question 38

What is habitat heterogeneity?

Answer 38

Spatial distribution and movement of species is driven by resource requirements.

Question 39

What is habitat fragmentation?

Answer 39

Alters habitat configuration, affects species movement patterns.

Question 40

Why does loss in biodiversity cause an acceleration of change in ecosystem functioning?

Answer 40

Biodiversity is non-linear and saturating.

Question 41

Can we predict future consequences of biodiversity loss?

Answer 41

By knowing how species affect the system, and how they respond to a driver of change, we can predict future consequences of ordered biodiversity loss.

Question 42

Why are diverse communities more productive?

Answer 42

They contain key species that have a large influence on productivity and differences in functional traits among organisms increase total resource capture.