16. Deforestation, Aforestation and agricultre

Question 1

What is the world cover for trees?

Answer 1

30%

Question 2

What is the forest cover in the UK

Answer 2

13%

Question 3

Why are trees important for ecology?

Answer 3

important for rich life and stream nutrients

Question 4

What is CWD

Answer 4

Coarse woody debris

Question 5

What is LWD

Answer 5

Large woody debris

Question 6

What impacts do fallen trees have on a stream

Answer 6

protects bank erosion, gravel traps, refuge, habitat, temperature stabilisation, shading, fish spawning

Question 7

What is Obligate WD

Answer 7

Only found on wood in streams

Question 8

WHat us Facultative

Answer 8

Found on other substrates as well as WD

Question 9

What is the problem with too much logs in the stream system?

Answer 9

Log jams, but not too much of a barrier

Question 10

What is the best gravels for salmonids

Answer 10

open gravels

Question 11

Which is the worst fines to have in the river?

Answer 11

<0.84mm

Question 12

What was the main cause of straighenting on the willamtte river?

Answer 12

river logging

Question 13

What happens due to increased timber harvesting

Answer 13

added light pollution on streams, nutrient leached from soils, greater development of phytobenthos, algae, greater densities of invertebrates

Question 14

What do sediments to the gravels in the streams

Answer 14

reduce permeability of the gravel, reduces salmon survival rate

Question 15

What animals might favour the introduction of sediment?

Answer 15

some worms fly larvae

Question 16

What is slash

Answer 16

woody debris that provides habitat

Question 17

How far from the bank is the most profitable trees from the bank

Answer 17

30m

Question 18

What is a method to manage tree loss

Answer 18

leaving a 30 meter buffer zone

Question 19

What is afforestation

Answer 19

planting forests

Question 20

Why is forests normally planted

Answer 20

for commercial use

Question 21

what are common species for afforestation

Answer 21

sitka spruce

Question 22

What percentage of the uk forest cover is commercial

Answer 22

12.9%

Question 23

What is the first stage for aforestation

Answer 23

ground preparation, building roads, making areas for growing, felling of other trees

Question 24

What are the issues with ground preparation

Answer 24

come back tp this

Question 25

What is the second stage of comercial AF

Answer 25

Closure of canopy,

Question 26

What is the problem with the second stage of AF

Answer 26

interception of wet and dry deposition, exclusion of light, reduced summer temperatures raised winter temperatures, reduced primary productivity

Question 27

What is the 3rd stage of AF

Answer 27

Felling and logging

Question 28

What can people do to stop acidification to streams?

Answer 28

Avoid planting conifers

Question 29

What is the main mining near rivers

Answer 29

gold and silver mining north america, coal mining and quarrying

Question 30

What happens with the channles during mining

Answer 30

movig the channel away from the mine, sediments enter the stream

Question 31

What minerals are common in tailings

Answer 31

zinc see slide

Question 32

What are the major mining impacts

Answer 32

heavy metals, chlorides, ferric hydroxide, fine sediments, smothers stream bed

Question 33

What ancient woodland do we have in the uk?

Answer 33

2.3%

Question 34

what happens mostly during deforestation

Answer 34

all trees gone, clear felling

Question 35

what is yarding?

Answer 35

Dragging poles to the centre of the felling site

Question 36

what does yarding create

Answer 36

sediments washed into rivers, ground disturbance, water runoff

Question 37

what temperature reigmes can we expect with less trees?

Answer 37

Colder in winter, warmer in summer

Question 38

What happens to the colour of the water after felling?

Answer 38

Increased turbidity

Question 39

What happens to slash in water?

Answer 39

decays and uses up oxygen

Question 40

What is the relationship between salmon and large woody debris?

Answer 40

The more debris the more salmon

Question 41

Where does the main source of the LWD come from

Answer 41

Within 30m of rivers on either side

Question 42

What does a 30m buffer zone prevent?

Answer 42

Slash debris, unwanted sediments

Question 43

which country protects own forest and imports wood?

Answer 43

Japan

Question 44

What is pressed disturbance

Answer 44

long and happens over time

Question 45

What mining process is the main release of chlorides

Answer 45

coal

Question 46

What is a settling pond

Answer 46

Area to store tailings after mining use

Question 47

What are gravels important for?

Answer 47

Fish spawning areas, insects

Question 48

What happens when we allow light into a system

Answer 48

Added nutrients, greater amounts of invertebrates, can be deadly though as unbalanced river

Question 49

Where there is an increase in algae biomass what do we see with fish?

Answer 49

Increase of fry

Question 50

What happens to stream flows if we remove forest cover?

Answer 50

More extreme flies, evapotranspiraton

Question 51

What does warm water lead to

Answer 51

Less oxygen

Question 52

When does permeability become lost?

Answer 52

When fines equal 15-20%

Question 53

What chemical impact can stage 1 afforestation be?

Answer 53

Nutrient leaching, herbicides

Question 54

What is ferric hydroxides?

Answer 54

Produced by iron mining?

Question 55

How can material be seperated out after mining

Answer 55

Settling ponds