EE.19

Question 1

other than climate what is the major determinant of community structure?

Answer 1

soils

Question 2

how do soils impact on ecosytems?

Answer 2

soil conditions affect plant growth
soil is a vital site for decompostion and nutrient cycling
soil is an essential habitat
organisms living in soil are a major part of food webs
soil is essential for watershed managemtn and agriculture

Question 3

what are the four main components of soil?

Answer 3

minerals
water
air
biotia

Question 4

what are the factors affecting the physical properties of soil?

Answer 4

• crumb structure, coherence, elasticity, porosity and permeability
• storage capacity for gas, water and heat
• organic matter, especially the humus colloids

Question 5

what factors affect the chemistry of soil?

Answer 5

• acidity
• composition of soil water
• the types an availabilty of nirtogen (ammonium, nitrates and nitites, organic)
• types of mineral and nutrients
• allelopathic and mineral toxins

Question 6

cation exchange capacity

Answer 6

the total number of cations which can be absorbed per unit weight of soil

Question 7

what are the three main factors influencing the great soil groups?

Answer 7

• water availability
• temperature
• geology (especially the pH)

Question 8

how is soil atmosphere different from air?

Answer 8

it contains far more CO2, 10-100 times more,
they contain far less oxygen
in waterlogged soils there is a huge increase in the amount of methane, ethylene,
ammonia and hydrogn sulphide
the amount of nitrogen though is the same

Question 9

what are the three main british soil types?

Answer 9

Podzol
Brown earth
Chernozem

Question 10

Podzol

Answer 10

podzol soils are acidic, and are found in regions of high rainfall
typical soils of coniferous, or boreal forests.
contain Iron Pan

Question 11

Brown earth

Answer 11

Common in lowland areas (below 1,000 feet) on permeable parent material. The most common vegetation types are deciduous woodland and grassland. Due to the reasonable natural fertility now used for farming.

Question 12

Chernozem

Answer 12

Calcareous soils found in areas of low rainfall, a black-coloured containing a high percentage of humus (7% to 15%), and high percentages of phosphoric acids, phosphorus and ammonia.

Question 13

Phosphorous

Answer 13

plant macro nutrient

required for nucleic acids and ATP

Question 14

Pottasium

Answer 14

plant macro nutrient

required for enzyme activation and water

Question 15

Sulphur

Answer 15

plant macro nutrient

required for proteins and coenzymes

Question 16

Calcium

Answer 16

plant macro nutrient

required for membranes and messages

Question 17

magnesium

Answer 17

plant macro nutrient

required for chlorophyll production

Question 18

iron

Answer 18

plant micro nutrient required for enzyme production and chlorphyll

Question 19

chlorine

Answer 19

plant micro nutrient required for photosynethesis and iron balance

Question 20

managenese

Answer 20

plant micro nutrient required for many enzymes

Question 21

boron

Answer 21

plnt miconutrient required for carbohydrate transport

Question 22

zinc

Answer 22

plant micro nutrient required for enzyme activation and auxins

Question 23

copper

Answer 23

plant micro nutrient required for redox enzymes and electrons

Question 24

molybedum

Answer 24

plant micro nutrient required in nitrogen metabolism

Question 25

nickel

Answer 25

plant micro nutrient required for nitrogen metabolism

Question 26

what causes the release of toxic aluminum ions in soils?

Answer 26

acid rain

Question 27

how do concentrations of mineral in the soil affect ecosystems?

Answer 27

the mineral supply affects what the primary producer will be and therefore the identity of the dominant plant species, which therefore impact on the rest of the ecosystem - the herbivores, and their natural enemy's, along with the community structure and productivity

Question 28

Calcium

Answer 28

calcium neutralises acids in soils, altering the pH values. it has numerous physiological effects on ion uptake, water uptake, membranes and it also acts as a catalyst, therefore affecting the formation, structure and humification of soils

Question 29

calicoles

Answer 29

plants which love chalk or limestone soils - lime lovers

Question 30

calcifuges

Answer 30

plants which love acidic soils low in calcium - lime avoiders

Question 31

Succession

Answer 31

the sequence of ecological changes in which one group of plant and animal species is replaced by another

Question 32

what are the two main types of succession?

Answer 32

- primary succession | - secondary succession

Question 33

what are the three main mechanisms of succession?

Answer 33

- faciliatation - inhibition - idosyncratic

Question 34

at the outset of primary succession what is the terrain like?

Answer 34

at the outset there is no soil, lots of sunlight, with very few nutrients available and typically a poor water holding capacity

Question 35

name 5 places you typically find primary succession

Answer 35

``` Lava Glacial retreat sea bed exposure sand dune rockfall ```

Question 36

describe the general processes of primary succession

Answer 36

first soil formation then nutrient capture, especially nitrogen after that organic matter starts to build up this then increases the diversity of plant life forms the plant maximum height increases plants start to compete for light instead of water and nutrients

Question 37

give a typical sequence of plants found in primary succession

Answer 37

Lichens -> mosses-> grasses-> shrubs-> trees

Question 38

where does secondary succession typically start?

Answer 38

in an area where well developed soil already exists, and the bare ground has been created by: tree fall, soil cultivation/construction works, fire, landslide, wind throw

Question 39

seres/seral stages

Answer 39

recognisable stages in succession

Question 40

climax community

Answer 40

endpoint of succession, and is supposed to be self replacing

Question 41

give an example of typical climax communities

Answer 41

woodland

Question 42

seral community

Answer 42

grasslands (prevented from developing into bush or woodland by annual fires, grazing by animals or both)

Question 43

Facilitation (relay floristics)

Answer 43

species A paves the way for species B which paves the way for species C ..... very important in primary succession, for example lichens making substrate for mosses there is little evidence for the importance of facilitation in secondary succession

Question 44

Inhibition

Answer 44

The opposite of facilitation, where instead species A stops species B from establishing, and species B is only able to invade once species A has suffered set back, for example a build up of its own specialist pathogens there is evidence for this from sand dune expression

Question 45

Initial floristic composition

Answer 45

the species which colonies ah area first are the ones which persist, for example fast growing grasses colonies an area first and come to dominate, slower growing species, such as trees, were there from the beginning however could only become dominance once they have over toppped rapid growers

Question 46

Resource ratios

Answer 46

these determine the identity of the dominant species depending on the resources available, a good competitor will be the species which can reduce the resource supply to the lowest level

Question 47

what does Tilman argue?

Answer 47

that resource ratios determine the identity of the dominant species

Question 48

are the best competitors the best colonizers?

Answer 48

no the best competitors are the worst colonizers | for example seed limitation is commonplace and dominant species must be seed limited, this is the main mechanism of IFC

Question 49

what are the two basic approaches to studying succession?

Answer 49

- repeated observations of permanent plots | - observations of different ages plots one at a time

Question 50

describe the chronosequence found at glacier bay, alaska

Answer 50

1. blue/green alga surust, lichens, liverworts and mosses 2. horsetails and scattered vascular plnts 3. Dryas drummondii -a nitrogen fixig mat forming dwarf shrub 4. Willows nd cottowood 5. Alder 6. Sitka spruce

Question 51

which plant in the succession series at glacier bay is able to fix niirogen?

Answer 51

Lichens - blue green algae Dryas drummondii (dwarf shrub) Sitka alder

Question 52

what forms the cimax community in glacier bay?

Answer 52

sitka spruce

Question 53

where is Piedmont plateau?

Answer 53

found lying between the blue ridge and appalachian moutains in the west and atlantic coastal plain in the east (south east america)

Question 54

what types of succession is found in piedemont plateau?

Answer 54

secondary

Question 55

what is the general series of succession in piedmont plateau?

Answer 55

abonded agricultrual land - old field stage -> hardwood forest

Question 56

what plant makes up the climax community in pidmont plateau?

Answer 56

oak