Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
31 Cards in this Set
- Front
- Back
|
What is a Forest canopy ?
|
Aboveground portion of a plant community or crop, formed by plant crowns.
(Also refers to the upper layer or habitat zone, formed by mature tree crowns, including other biological organisms) (For forests) (Ex of organisms: epiphytes, lianas) |
|
|
What are plant crowns
|
Totality of the plant`s aboveground parts (stems, leaves, reproductive structures)
|
|
|
What does species diversity refer to?
How can species diversity be assessed? |
-Variety of species
-a-diversity (the diversity og species within a habitat or community) B-diversity (the rate of change of species along a gradient from one habitat to another) y-diversity (richness of species in a range of communities in a location or from one location to another on a geopgraphical scale) |
|
|
Describe 3 different groups of hypotheses that may explain the relationship of species diversity to latitudinal gradients. Include examples.
|
1) HISTORICAL (constant climate hypotheses, tropical niche-conservatism hypothesis)
2) EVOLUTIONARY (evolutionary speed hypothesis, matabolic rate theory, speciation rate hypothesis) 3) ECOLOGICAL (physiological tolerance-hypothesis, energy richness hypothesis, intermediate disturbance hypothesis) |
|
|
How are gaps created in the forest canopy?
|
Through the death of a tree and through events such as landslides and hurricanes
|
|
|
What are pioneer species, and what do they require?
Are they slow or fast growing? Do they live long or short? |
First organisms to colonise an area
And SPECIES which occur in the early stages of succession High light intensities for germination. Fast-growing. Short -lived (comparatively) |
|
|
What are climax species?
|
Species that occur in the later stages of succession.
|
|
|
What is Succession?
|
Non-seasonal, sequential change in the SPECIES composition of a site in response to either environmental change or to change induced by the organisms themselves
|
|
|
What is allogenic succession?
What is autogenic succession? What is primary succession? (Give examples) What is seconadry succession? (Give examples) |
-Succession brought about by a change in the ABIOTIC environment
-Succession resulting from modification of the environment by the organisms inhabiting it -sequential change in the vegetation, starting with the colonisation of a site not previously occupied by organisms (lava flow, sand dune, bare rock) -Sequential change in the vegetation recolonising a site previously occupied by organisms. (Gap in canopy, or abandoned field) |
|
|
Define ABIOTIC
Define BIOTIC What are examples of ABIOTIC factors? What are BIOTIC factors? Give examples. |
-NON-living components of the environment
-Describing living things Temperature, wind patterns, humidity, ph, substrate rock types Biotic factors: environmental features resulting from interactions between organisms; PREDATION, PARATISISM |
|
|
How can a dominant species have an advantage over competitors(trees)?
|
Through possession of an EM (ectomycorrhizal association)
|
|
|
What is VAM short for?
|
vesicular-arbuscular mycorrhizal association
|
|
|
Where do most trees have a VAM association?
|
In the Neo-tropics and Africa
|
|
|
What are three advantages of EM association?
|
Greater host specificity
Greater protection to the host tree from natural enemies Enhanced ability to secure nutrients in both organic and inorganic form. |
|
|
What is forest fragmentation?
|
Forests are cut down, leaving small isolated patches
|
|
|
What are some negative consequences of forest fragmentation, and where is this worse?
|
Reduces habitat size and exposes organisms to stressful environmental conditions.
At the forest edges. |
|
|
What does edge effects include. Name 3 effects.
|
1. Abiotic effects (changes in environmental conditions)
2. Direct biological effects (changes in abundance and distribution of species) 3. Indirect biological effects (Changes in species interactions such as predation, competition, herbivory, pollination and seed dispersal) |
|
|
What are Keystone species
|
Species which has a significant influence on the composition and function of a COMMUNITY.
|
|
|
What is a negative effect of removing the Keystone species?
|
It may lead to death or disappearance of dependent species.
|
|
|
What is a flagship species?
|
Species with significant appeal to humans that can draw attention to issues of habitat conservation.
(Conservation agencies focus their efforts on habitat protection rather than selected, charismatic organisms) |
|
|
What is detritus?
|
Dead organic matter
|
|
|
What are some reasons for conserving rain forests?
|
Goods and services that these systems provide
The poor agriculture potential of many rain forest soils ethical and aesthetic considerations |
|
|
What is Biodiversity conservation focused on?
|
Monitoring species that are in decline and on habitat protection through establishment of protected areas.
|
|
|
Forests cover x% of the earth`s surface?
Forests contain approx. x% of the world´s species. Fill in correct number for X. |
7%
50% |
|
|
How many layers are Rain forests stratified with?
Name two layers. |
Two or three layers
Shrub layer Herb layer |
|
|
What is phonology the study of?
|
Leaf, flower and fruit production and other events which seem to be related to climate
|
|
|
How can plants be classified?
What is Raunkiaer`s classification of plants based on? |
With respect to their GROWTH FORM.
On the POSITION, relative to the ground, of the PERENNATING organs |
|
|
How have rain forest plants and animals developed?
|
Through EVOLUTION and CO-EVOLUTION, intricate offensive and defensive relationships
|
|
|
What are the mean monthly temperatures in Tropical Rain forests?
|
Not much below 25C
Rarely Exceed 35C |
|
|
How high can the diurnial temperature variations be?
|
10C
|
|
|
What are the tallest trees in rain forests called?
How high do they grow? How high are the middle-storey trees? |
Emergents
45-50m 25-35m |
