EE Lecture 19: Plants, Soils and Succession Flashcards
1
Q
what are the two major determinants of community structure
A
climate and soils
2
Q
what are main uses of soil
A
decomposition and nutrient cycling
habitat
soil orgs are major food source
soil conservation for agriculture
3
Q
what are main components of soil
A
mineral water air biota
4
Q
name some physical properties of soil
A
crumb structure coherence elasticity porosity permeability storage capacity -water gas heat
5
Q
what can soil store
A
wter
gas
heat
biota
6
Q
what does amount of soil storage depend on
A
humus colloids
7
Q
what types of nitrogen is available in soil
A
organic N
ammonium
nitrates nitrites
8
Q
what is cation exchange capacity
A
the total no. of cations that can be adsorbed per unit weight of soil
9
Q
what is the total no. of cations that can be adsorbed per unit gram of soil called
A
cation exchange capacity
10
Q
what are great soil groups influenced by
A
water available
temp
geology -pH
11
Q
in what way is soil atmosphere different from air
A
less oxygen
more CO2
same nitrogen
12
Q
how is waterlogged soil different in composition to normal soil
A
there is increased methane/ethylene ammonia, hydrogen sulphide
13
Q
what are soil profiles dependent on
A
plant material climate living orgs topography duration of pseudogenesis
14
Q
what is pseudogenesis
A
formation of soilge
15
Q
wht are the chemically and physically distinct layers of soil called
A
horizons
16
Q
what are horizons
A
organisation of soil into chemically and physically distinct layers
17
Q
HOW MAny horizons is a normal soil profile split into
A
5: 0 A B C D
18
Q
how is soil formed
A
- additions
- losses through wind/water/plant uptake
- transformation
- translocation
19
Q
in what way can soil be lost
A
wind
water
plant uptake
20
Q
what is the 0 horizon
A
organic debris, leaf litter
21
Q
what is the organic debris layer of soil called
A
the 0 horizon
22
Q
what is the A horizon
A
top surface soil - dark layer of mixed organics and mineral - max biological activity
23
Q
what is the top surface soil layer called
A
the A horizon
24
Q
which layer of soil has the most biological activity
A
A horizon : top surface soil layer
25
what is the B horizon
transitional layer - accumulation of material leached from A
26
what is the horizon which is a transitional layer with accumulation of material leached from A
B horizon
27
what is the C horizon composed of
weathered parent material - drift
28
which soil layer is composed of weathered parent material
C horizon
29
what is the D horizon
non-parent under stratum eg rock
30
what is the non-parent under stratum called
D horizon - rock
31
name some british soil type
podzol acid soils
brown earth fertile soils
chernozen calcareous soils
32
where are podzol acid soils and chernozen calcareous soils normally found
in Britain
33
describe podzol soils
acidic soils
| high rainfall
34
describe chernozem soils
calcareous soils
| low rain
35
describe brown earth soils
fertile
36
name an acidic soil with high rainfall
podzol soil
37
name a highly fertile soil
brown earth soil
38
name a calcareous soil
chernozem
39
what are major macronutrients of plants
```
P
K
S
Ca
Mg
```
40
name some micronutrients needed by plants
```
Fe
Cl
Mn
B
Zn
Cu
Mo
Ni
```
41
name some micronutrients needed by plants for nitrogen metabolism
Ni
| Mo
42
how can soils be polluted minerally
lots of heavy metals Cu,Ni,Zn that are micronutrients in small quantities but are toxic to plants when found at high concentrations
43
name some heavy metals that can pollute soils
Cu
Ni
Zn
44
when can micronutrients like Cu Ni and Zn become toxic to plants
when present at high concentrations in soils
45
outline main roles of Calcium in soils
neutralises acids
alters pH
physiological effects - catalyst, ion uptake, water uptake,membranes
affecs soil condns - humification, soil formation, soil structure
46
in what way does calcium affect soil pH
neutralises acids
47
what physiological effects does Calcium have
catalyst
ion uptake
water uptake
membranes
48
how does calcium affect soil condn
humification
soil formation
soil structure`
49
name some calcium (in)dependent plant species
Calcicole
| Califuge
50
what are calcicoles
plant species that love chalk/limestone
| plants characteristic of lime soils
51
what are califuge species
plants characteristic of acidic soils - low in calcium
52
what are plants characteristic of calcium rich soils called
calcicoles
53
what are plants characteristic of acidic soils low in calcium called
califuge
54
what can an excess of calcium in soils cause
a deficiency of potassium, magnesium and certain trace elements
55
what are lime avoiders called
calcifuge
56
what are lime lovers called
calcicoles
57
how can a deficiency of potassium, magnesium and certain trace elements be cause
by an excess of Ca in soil
58
give an example of how soils determine the identity of the dominant plant species
Nardus stricta - a califuge - not common in SE but everywhere else, whereas Anthyllis vulneria - calcicole is present where Nardus stricta isnt
59
name a calcicole
anthyllis vulneraria
60
name a calcifuge
nardus stricta
61
is anthyllis vulneraria a clacicole or calcifuge
anthyllis vulneraria is a calcicole
62
is nardus stricta a calcicole or calcifuge
nardus stricta is a calcifuge
63
where is nardus stricta most commonly found in britain
in SE where soils are acidic - anywhere where anthyllis vulneraria isnt found
64
define succession
the sequence of ecological changes in which one group of plant and animal species is replaced by another:
changes in a definite direction
65
what types of succession is there
primary or secondary
66
what are the mechanisms for sucesion
facilitation (relay floristics)
inhibition
idiosyncratic (initial floristic competition)
67
what is facilitation aka
relay floristics
68
what is idiosyncratic aka
initial floristic competiition
69
where does primary succession occur
```
lava
glacial retreat
sea bed exposure
sand dune
rockfall (talus or scree)
```
70
what type succession likely to occur from glacial retreat/rockfall
primary
71
what are the main processes in primary successtion
soil formation
nutrient capture -spesh nitrogen
organic matter build up
inc diversity
inc max plant height
good compeitiors for water and nutrients are replaced by good competitiors for light
typical sequence: lichens - moss - grass - shrubs - tres
72
in primary succession, what are good competitors for nutrients and water likely to be replaced by
good competitors for light
73
what is a typical primary succession sequence
lichen - moss - grass - shrub - trees
74
what type of succession is the following typical of
| lichens - moss - grass- shrub - tree
primary
75
what is main nutrient capture in primary succession
nitrogen
76
how is secondary succession different from primary
a well developed soil already exists, bare ground is just created by:
fire/deforestation/tree fall/land slide/wind throw/soil cultivation
77
how is bare ground created for secondary succession
```
fire
wind throw
land slide
deforestation
soil cultivation or construction work
```
78
what are seres
the recognizable stages of succcession
79
what are the recognisable stages of sucession called
seres
80
what is the climax community
the end point of succession
81
give an example of a typical climax community
woodland
82
what are most grasslands in succession
seral
83
how are most grasslands prevented from developing into climax community
by fires/grazing animals
84
what effect do fires/grazing animals have on seral species
prevent them from developing into climax community
85
what succession mechanism is most important in primary succession
facilitation
86
what type of succession is facilitation a mechanism of
primary
87
what is facilitation also known aas
relay floristic mechanism
88
why is facilitation also known as relay floristic mechanism
because species A paves way for Species B which paves what for C and so on
89
what is the succession mechanism "inhibition"
opposite to facilitation
species A stops B from establishing
B can only invade once A has suffered a set back eg. build up of specialist pathogens
90
where has inhibition been seen in successsion
in primary succession of sand dune
91
how does a species overcome inhibition in succession
can only invade if the inhibiting species suffers a set back - eg. build up of its specialist pathogens
92
what does the idiosyncratic mechanism of succession involve
initial floristic composition
the species that get there first are the pones that persist,
fast growing colonists come to dominance first eg. grasses
slower growing species eg trees were there from beginning eg. as seedlings but only came to dominance once they overtopped the rapid growers
93
what is the succession mechanism that states that first growing colonists are the ones that persist
initial floristic composition
| idiosyncratic
94
give an example of idiosyncratic succession (initial floristic composition)
trees there from beginning eg.as seedlings but only come to show when theyve overtopped the fast growing rapid species eg. grasses
95
define good competitors in terms of what they do to R*
they reduce resource supply to the lowest level of R*
96
what doeoes a low R* mean
dominance
97
what trade offs are faced in succession
colonization - competition trade off
| the best competitors are the worst colonizers
98
what are the main mechanisms for studying succession
repeated observations of permanent plots through time
| observations of different aged plots at one time - a chronosequence using space for time substitution
99
what is a chronosequence for succession
observation of different aged plots at one time - use space for time substitution
100
name example of primary succession
glacial moraine succession in SE Alaska
101
name an example of secondary succession
Old Field succession in E. US Piedmont plateau
102
what type succession in glacier bay, alaska
primary succession
103
what type succession in old field, e. US piedmont plateau
secondary succession
104
outline succession in glacier bay, alaska
200yr chronosequence
1. blue green algal crusts,lichens,liverworts,mosses:nitrogen fixers
2. horsetails and scattered vascular plants
3. dwarf shrub Dryas drumondii
4. Willows (Salix) and Cottonwood (Populus)
5. Alder
6. Sitka spruce
105
what do most colonizing species in primary succession have in common - give examples
mostly nitrogen fixers
| liverworts, algal crusts, lichens, mosses
106
what is the climax community of Glacier Bay
Sitka spruce ~200yrs
107
outline succession in Old Field in Piedmont plateau
```
0.Crops
1,conyza canadensis
2.ambrosia artemisfolia, aster pilosus
3. andropogon virginicus
5-40. Pine and juniper
41+ Oak
```
108
what is climax community in Piedmont plateau - after how many years
oak
| 41+ yrs
