Value of biodiversity

Question 1

Key concepts

Answer 1

• Ecosystem functions: The biological, geochemical and physical processes that take place within a ecosystem
• Pollination: process where pollen is exchanged between plants, a critical step in the regeneration of primary
  producers
• Primary production: process where plants use sunlight, CO2, water and nutrients to add organic material (and
  energy) into ecosystems
• Decomposition: process where microbes, fungi & animals process dead organic tissue, releasing nutrients

Question 2

More Key concepts

Answer 2

• Ecosystem services (and goods) The benefits that humanity derive from ecosystem functions
• Regulating services: lessen (regulate) environmental change → climate regulation, pest/disease control, flood regulation
• Provisioning services: based on the production of (renewable) resources → food, fibre, energy, freshwater

Question 3

Do biodiverse ecosystems function more effectively?

Answer 3

1. BD increases efficiency of resource gain in ecosystems
2. BD increases the stability of ecosystem functions
3. Effects of BD on functions in non-linear and may saturate
4. Functional traits are a key control on BD-functioning relationships
   Result in positive relationships between biodiversity and
   ecosystem services → provides a framework for valuing
   biodiversity

Question 4

What are the key ecosystem services provided by forests?

Answer 4

• Timber (provisioning service)
• Food (provisioning)
• Climate regulation (regulatory)
• Water regulation (regulatory)

Question 5

Why is productivity higher in more diverse forests?

Answer 5

• Mixed forests capture more light, arrange the canopy more efficiently
• Similar things happen below-ground e.g. rooting at different depths to maximise nutrient and water uptake
• Effect even greater if species mix is functionally diverse and includes a mix of evolutionarily distinct species

Question 6

Value of a stable ecosystem service?

Answer 6

• Efficient ecosystem services - more productive forests or pastures
• Stability is higher in mixed-species forests compared to single species forest
• Stability generally increases with increasing species richness
• Stability = mean/ SD