Lab 5

Question 1

flora

Answer 1

a flora is a list of plant species that occur in a given area where the order of species is related to ease of use.

A flora gives no indication of the importance or abundance of the species present.

Question 2

Vegetation

Answer 2

A vegetation is a list of plant species that occur in a given area where the order of species is related to importance or abundance of each species present.

Question 3

quadrats can be almost any shape but _____,____,____ are most common

Answer 3

quadrats can be almost any shape but circles, squares and rectangles are most common

Question 4

Quadrat sizes for different vegetation:

Moss, Lichen
Grasses and forbs
Shrubs
Trees

Answer 4

Moss, Lichen - 0.1 to 0.25 m^2
Grasses and forbs - 0.25 to 2 m^2
Shrubs - 10 to 15 m^2
Trees - 100 to 150 m^2

Question 5

A point intercept method cannot generate _______

Answer 5

density data

Question 6

Areal Cover

Answer 6

Areal cover can be defined as the vertical projection of the above-ground parts of each plant onto the ground.

Question 7

Many ecologists have emphasized cover as being of greater ecological significance than _____

Answer 7

density

Question 8

Cover gives a better measure of plant biomass than does the ________

Answer 8

number of individuals

Question 9

What is used to determine Leaf Area Index (LAI)

Answer 9

Cover

Question 10

Leaf Area Index (LAI)

Answer 10

The ratio between the total leaf area above the soil surface and the soil surface area.

As there can be more than one layer of leaf material over the same soil surface, LAI can range from close to 0 in true desert to almost 5 in tropical rainforest.

Question 11

PAR

Answer 11

Photosynthetically Active Radiation

Question 12

PAR in a forest

Answer 12

In a forest the trees have access to all the available PAR while the shrubs receive only the PAR that has not been absorbed or reflected by the canopy leaves.

Question 13

How is frequency best expressed for comparing different communities?

Answer 13

frequency best expressed as a percentage of the total number of placements, i.e. the frequency percentage or frequency index.

Question 14

frequency provides an __________ but it is a non-________ measure.

Answer 14

frequency provides an objective assessment but it is a non-absolute measure.

Question 15

Sources of error in frequency estimates

Answer 15

• Size of quadrat
• size of the individual plant
• spatial distribution of individuals

Question 16

Types of frequency

Answer 16

Shoot frequency

Rooted frequency

Question 17

Shoot frequency

Answer 17

obtained by recording as present all foliage overlapping into a quadrat

Question 18

Rooted frequency

Answer 18

records a species being present only when it is actually rooted in the quadrat.

Question 19

Which is the most common applied quantitative parameter for the analysis of forest undergrowth and herbaceous communities in North american description studies?

Answer 19

Frequency

Question 20

Density

Answer 20

Density refers to the number of individuals per unit area usually obtained by a simple count of plants in a series of random quadrats.

The process is extremely time consuming but is also extremely accurate allowing different direct comparisons of quadrats in different areas.

it is suitable for early stages of colonization

Question 21

Difficulty of using density estimates

Answer 21

The recognition of individuals. In spreading shrubs it is often difficult to decide where on individual begins and another ends. Also rhizomatous and stoniferous forms can hardly be counted accurately. Another difficulty is the marginal effect of the quadrat.The quadrat boundaries may go through an individual and a decision has to be made whether to count it or exclude it.

Question 22

Biomass

Answer 22

The term biomass refers to the total dry weight of biological material per unit area and is usually obtained by harvesting plants in a series of random quadrats. These plants are then dried at 60 degree C until a constant dry weight is achieved.

Biomass represents stored energy and biomass data is relatively accurate in most instances and is generally used in studies where energy within the ecosystem is being examined.