ECEC - 2 Flashcards
what percentage of the UK is woodland?
12%
what are the 3 main types of stem-natural woodland?
1) native
2) ancient
3) recent
what percentage of UK woodlands are native and what do they consist of?
40%
- consist of native trees that have grown in the UK since the ice age
what defines an ancient woodland?
woodland consistently wooded since 1600 AD
what defines recent woodland?
- planted or established naturally
whats the difference between primary and secondary woodland?
primary - survived continually since the ice age
secondary - planted or established since last ice age
what are 2 reasons communities occur?
1) environmental factors
2) community processes
what is the definition of structure and its 3 components
the spatial organisation of plant material within a community
1) vertical structure (stratification)
2) horizontal structure (pattern)
3) species abundance
what are the 4 layers of a woodlands vertical structure?
1) ground layer
2) field layer (tall herbs and undershrubs) + ( layer of low herbs)
3) shrub layer
4) tree layer
what are the 3 main types of horizontal structure?
1) regular
2) random
3) clumped
what are the 4 things that determine a pattern shown by a species?
1) morphology and growth characteristics
2) seed dispersal mechanisms
3) environmental heterogeneity
4) species interactions
what are 4 ways species abundance can be measured?
1) guesstimates DAFOR: Dominant, Abundant, Frequent, Occasional, Rare
2) density - number of individuals per unit area
3) frequency - Chance of finding a particular species in a sample of vegetation
4) cover - expressed as a percentage - can be over 100% if vegetation overlaps
what are the 2 main approaches to survival on the forest floor?
1) shade tolerance
2) complementation - growing when the light intensity is relatively high
what is a way shade tolerance plants are adapted to survival
- often have large, thin leaves
- leaves with a single palisade layer
- large surface area to weight ratio
- they respire more slowly
what is complementation and examples of 2 species?
when woodland floor plants grow before the main development of tree canopy with early growth and flowering
examples: 1) wood anemone 2) dogs mercury
what is phenology?
the study of the seasonal periodicity and timing of plant growth
what are the 4 classifications for time of year plants grow in?
1) vernal = spring
2) Aestival = summer
3) Autumnal = autumn
4) hiemal = winter
what is the difference between brown forest soil and podzol soil?
- Podzol soil is more acidic
- brown forest soil is actively mixed by organisms
- podzol soil has sharp boundaries between layers and isn’t mixed
how many species of native trees and shrubs does the UK have?
50
what are examples of community processes?
- competitive exclusion
– co-existence through tolerance
– co-existence through complementation
– dependence
what is the definition of species abundance and what is it useful for?
- the amount a species contributes to the vegetation
Important in vegetation descriptions, naming and classifying communities
when is morphological plasticity of shading most likely to occur?
- more typically of plants of little-shaded conditions
- Less so for species in consistently in deep shade
describe the leaves of Deschampsia flexuosa, (grass)?
- doesnt have the leaves of normal plants which grow in shaded environments
- has narrow, bristle-like leaves
- tolerates “temporary shade” because
evergreen
what does ever green mean?
plants which keep their green leaves all year round
what tree dominates many relict oakwoods on acid soils in northern and western Britain?
Quercus petraea (sessile oak)
describe the Coed Cymerau study?
- an upland oakwood with little evidence for oak regeneration
- Many acorns produced with high viability
- BUT 99% wastage of fallen acorns - rodent predation
- HOWEVER, sufficient acorns persisted to ensure regeneration
the coed cymerau study showed there to be a sufficient amount of acorns to ensure regeneration why isnt there?
D. flexuosa - a poor trap of oak leaf litter (blown out of woods)
– Loss of important medium for acorn germination
– Loss of important cover to reduce rodent predation of acorns
