6.6.4 sustainable management

Question 1

positive of sustainable management of ecosystems

Answer 1

biodiversity is maintained whilst ensuring supplies & maintaining economic benefits

Question 2

describe coppicing

Answer 2

• provides sustainable supply of wood
• stem of deciduous tree cut close to ground
• new shoots emerge from cut surface & mature into narrow stems
• used for fencing, firewood & furniture
• new shoots grow once cut again & cycle continues!!!

Question 3

describe pollarding

Answer 3

• cutting stem higher up
• prevents deer eating new shoots (if high deer pop.)

Question 4

describe rotational coppicing

Answer 4

• woodland managers divide wood into sections & cut 1 section a year
• each section, some trees left to grow larger = ‘standards’ & eventually harvested for larger pieces of timber
• good for biodiversity
• diff. areas of woodland provide diff. habitats, letting more light in & increasing number/diversity of species

Question 5

what happens if woodland left unmanaged

Answer 5

• goes through process of succession
• blocks out light to woodland floor
  = reduces no. of species growing there

Question 6

negatives of past large-scale timber production

Answer 6

• clear felling all trees in 1 area
• destroyed habitats
• reduced soil mineral levels
• leave soil susceptible to erosion
• soil may run off into waterways = pollute
• trees maintain soil nutrient levels via role in nitrogen/carbon cycles

Question 7

following principles modern sustainable forestry follows

Answer 7

• any tree harvested is replaced (grown naturally or planted)
• forest must maintain ecological function (biodiversity, climate & mineral/water cycles)
• local people benefit from forest
• selective cutting includes removing only largest/most valuable trees
• sustainably managing forests: balancing conservation & need to harvest wood, maintain biodiversity & make woodland pay for itself (each tree supplies more wood, less need to be harvested)

Question 8

how do foresters make trees supply more wood (so less need to be harvested)

Answer 8

• control pests/pathogens
• only plant certain species known for growing well
• position trees at optimal distance apart to reduce competition

Question 9

which council proposed 3 principles for sustainable management of fisheries

Answer 9

the marine stewardship council

Question 10

3 principles for sustainable management of fisheries proposed by marine stewardship council

Answer 10

1) fishing must take place at level which allows it to continue indefinitely & over fishing must be avoided
- if occurs, reduce fishing to let stocks recover which can rapidly increase productivity & good for profitability
- optimum = maintain fish pop. at carrying capacity of environment

2) fishing must be managed to maintain structure, productivity, function & diversity of ecosystem
- no permanent damage & any effect on dependent species minimised

3) fishery must adapt to changes in circumstances & comply w/ local, national & international regulations

Question 11

another way to provide sustainable fish stocks

Answer 11

= aquaculture

• restricts impact on oceanic fish stocks