Forest resources

Question 1

name the 3 types of forests and their biodiversity

Answer 1

• deciduous (High biodiversity)
• coniferous (low biodiversity)
• tropical rainforests (highest biodiversity)

Question 2

what does LEDCs and MEDCs stand for?

Answer 2

LEDCs = least economically developed countries 
MEDCs= most economically developed countries

Question 3

name the 6 resources gained from forests

Answer 3

1. timber
2. fuel
3. food
4. fibres
5. medicines
6. genetic resources

Question 4

why is timber and fuel important resources? and why are they being overexploited?

Answer 4

• as pop. increases, increased demand for timber

fuel = burning wood biggest provider of energy for cooking, mainly in LEDCs

Question 5

why is food important resources? give examples and why are they being overexploited?

Answer 5

i.e. trees fodder for livestock, Nuts/fruits for humans. Bushmeat in LEDCs.
- Many plant species from forests i.e. cacao/bananas
+ forests could provide new, future food resources

Question 6

why is medicines (examples) important resources? give an example and why are they are being overexploited?

Answer 6

• some still extracted from trees.
• forests not been researched for medicinal properties.
  i. e. Aspirin came from willow bark

Question 7

name the 5 ecosystem services forests provide

Answer 7

1. atmospheric regulation
2. regulation of hydrological cycle
3. habitat/wildlife refuge
4. soil conservation
5. climate regulation

Question 8

explain the 3 ways how forests help to regulate atmosphere

Answer 8

1. reservoirs of C: carbon sequestration (store in cellulose) and photo. takes in C
2. Photo: produces O2 = respiration + maintenance of O3 layer
3. These processes increase C in biomass reservoir = less C in atmo.

Question 9

explain the 3 ways how forests help to regulate hydrological cycle

Answer 9

1. transpiration greater in forests: increase evap. more H2O in atmo.= increase rain
2. interception: increase evap. decrease infiltration
3. leaf litter/deeper soils: increase infiltration (delayed runoff = river levels fluctuate less + aquifer recharge)

Question 10

explain how forests provide habitat and wildlife refuge

Answer 10

1. biodiverse terrestrial ecosystems: different varieties of trees/stratification = different ecological niches
2. high primary productivity: lots of energy (support higher trophic levels)
3. trees create variations in abiotic factors i.e. temp/light levels + humidity/wind velocity

Question 11

explain the 3 ways how forests aid soil conservation

Answer 11

1. DOM: humus + nutrients/food for biota. (Humus = binds soil)
2. trees/vegetation: increase interception = reduce splash erosion + windbreaks = less wind erosion
3. soil biota: aerate soil = increase O2 for aerobic processes + increased infiltration = less runoff/erosion

Question 12

explain how forests regulate global climate

Answer 12

• Decrease temp: photo+ carbon sequestration

- Less IR being absorbed

Question 13

name at least 4 out of the 6 factors that influence choice of species for forest plantations

Answer 13

1. growth rates
2. resistance to pests/disease
3. demand for particular products
4. ability to grow in certain soils
5. ability survive in climate conditions
6. properties of wood

Question 14

differences between the abiotic and biotic factors in a plantation and a natural forest

Answer 14

abiotic: plantation lower light levels (denser canopy), less wind velocity
biotic: plantation less varieties of trees and more uniform = less ecological niches. pest outbreaks have higher impact

Question 15

name the 4 forestry practices that increase productivity

Answer 15

1. growth of non-indigenous species
2. close planting
3. monoculture
4. simple age structure

Question 16

explain how the growth of non-indigenous species increases productivity (2) Include examples

Answer 16

+ species better adapted to environmental conditions
+ less likely suffer damage from local pests/diseases
= eucalyptus to East Africa (originally from Australia)

Question 17

explain why monoculture increases productivity + impact on biodiversity

Answer 17

+ management of plantation easier
+ activities i.e. planting/felling carried out at same time
- decreases microhabitats/ecological niches = less biodiverse

Question 18

explain why close planting increases productivity (2)

Answer 18

+ trees compete for light so grow tall/straight (more marketable)
+ suppresses growth of weeds

Question 19

explain why a simple age structure increases productivity + impact on biodiversity

Answer 19

+ trees of similar sizes = similar tree management at same time so easier management
- reduction in abiotic factors
+ trees felled when income at greatest and growth rates slow
- less dead wood = less DOM, less nutrients for plants, they die

Question 20

how does mixed species plantations increase sustainable management? (3)

Answer 20

• increase variety of resources for other species i.e. food/habitats etc.
• increase range of interspecies relationships + niches
• increase biodiversity

Question 21

what are the drawbacks of mixed species plantations? (2)

Answer 21

• less useful if there is a specific product that is in demand
• less commercially viable

Question 22

how does the use of indigenous species increase sustainable management? (2)

Answer 22

• trees suited to local climate

- resources for indigenous species/interspecies relationships

Question 23

what are the drawbacks for use of indigenous species? (3)

Answer 23

• less suited to local fungi/disease
• may not grow as fast
• produce less desirable wood

Question 24

how does mixed age structure increase sustainable management?(3)

Answer 24

• range of microhabitats/niches = increase biodiversity
• no need to harvest at same time (not all be mature) = minimises wildlife disturbance + soil erosion
• range of abiotic factors present i.e. light, temp etc.

Question 25

how does selective logging increase sustainable management? (5 points)

Answer 25

- certain species can be chosen i.e. if important to wildlife/sensitive areas left alone - useful for mixed species (mature at different times) - use narrow access pathways (horse drawn carts/heli -logging) = no need for heavy machinery - overall yield increased = each tree meets maturity instead of using clear felling method - less soil erosion = ground always has vegetation

Question 26

what are the drawbacks of selective logging? (2)

Answer 26

- more labour intensive | - more overall time/effort

Question 27

name the 3 activities that are considered for clearance for alternative land uses

Answer 27

- agriculture/cattle farming: as pop. increases so does demand for food = more land needed for crop/livestock - urbanisation: as pop. increases needs more housing - mineral extraction: mining/associated structure. Increased demand for metals/minerals

Question 28

how do the loss of forests have an impact on soil conservation? (4)

Answer 28

- less DOM: less nutrients - less roots: less soil stability, increase erosion. Increase turbidity in waterways (anaerobic conditions) - less foliage: decrease interception = increase impact of raindrops. Also increase wind erosion - less soil biota: less aeration = less infiltration = more runoff. Less aerobic processes

Question 29

how do the loss of forests have an impact on hydrology? (3)

Answer 29

- less evapotranspiration: less H2O in atmo. = less rain - less interception - increase runoff: increase risks of flooding = money needed for defences. Increase river level fluctuations

Question 30

the impact on climate regulation with loss of forests: 1. less _________. 2. Less carbon _________: increases CO2 in ________ = decreases carbon in _______ reservoir. increase _______ greenhouse effect 3. less ______ being produced: ______ needed for ________ respiration. decrease in _____ layer = UVB and UVC may not be ______.

Answer 30

1. photosynthesis 2. sequestration, atmosphere, biomass, enhanced 3. oxygen, oxygen, aerobic, ozone, absorbed

Question 31

how does the loss of forests impact biodiversity? (4)

Answer 31

- decrease in biodiversity, decrease in niches/variety - loss of habitats/inter relationships: less seed dispersal, loss of food - less variations in abiotic factors - increased fragmentation: isolating groups of species and increased chance of inbreeding

Question 32

how does loss of forests change abiotic factors?

Answer 32

1. increased wind velocity 2. less humidity 3. higher light intensity 4. increased temp

Question 33

why are fibres important resources? give 2 examples of fibres and why are they being overexploited?

Answer 33

i.e. paper (flattened sheets of interwoven cellulose), cotton (fibres that surround seeds on cotton bush) + growing fashion/textile industries

Question 34

why genetic resources important resources? give examples and why are they are being overexploited?

Answer 34

CWR new genes = new characteristics for selective breeding. + increase demand/importance as biotech associated with agriculture improve crops due changes in climate i.e. Cacao + CWR in amazon: drought resistant

Question 35

explain 3 ways how forests regulate a microclimate

Answer 35

- Trees windbreaks: lower wind velocity = plants below canopy rely on animals for pollination/seed dispersal - high humidity from evapotranspiration = amphibians can survive - light levels: canopy absorbs solar insolation = plants living below less light adaptations i.e. additional pigments/denser chlorophyll

Question 36

explain how the growth of non-indigenous species impacts on biodiversity (2)

Answer 36

- less likely to support indigenous species | - less interspecies relationships needed for: food/ pollination/dispersal not present

Question 37

explain how close planting impacts biodiversity

Answer 37

- decrease light levels (inhibits growth of other plants) | - decrease in those plants and species that rely on them = reduce biodiversity