Change in Ecosystems

Question 1

Succession

Answer 1

Process of change in the species and ecosystems over time.

Question 2

Sere

Answer 2

A successive community, replaces previous sere until a stable community is reached.

Question 3

Pioneer Community

Answer 3

Have traits that fit them to live in harsh environments, are very tolerant species that normally symbiose well with soil bacteria.

Question 4

Eutrophication

Answer 4

Change of an aquatic environment from one that is low in nutrients to one that has very high levels of nutrients, therefore is more fertile and productive.

Question 5

Primary Succession

Answer 5

Bare, undisturbed area is colonised by organisms (a pioneer community) for the first time.

Question 6

Secondary Succession

Answer 6

Previously inhabited, disturbed (natural disasters or human disasters) areas are reclaimed by organisms.

Question 7

Fossil Records

Answer 7

Fossils are used in many different ways to identify changes in both biotic and abiotic factors in the past and determine what caused the changes.

Question 8

Human Activity Causing Change

Answer 8

• Land clearing
  
  • Habitat fragmentation
  • Dryland salinity
• Increasing carbon
  
  • Burning fossil fuels
• Introduction of new species
  
  • Human activities can transfer
    organisms into places where they
    previously did not exist; e.g. cane
    toads.