Intro to forest ecosystems Flashcards
How much of the earth’s land mass is forests?
~1/3
How much of the earth’s plant leaf area do forests make up?
~2/3
How much of the earth’s biomass do forests contain?
80-90%
how much of the carbon stored in living organisms is contained in forests?
~70%
how much of the earth’s terrestrial biodiversity do forests contain?
> 80%
What are 5 important things that forests do for the planet and us?
protect soil
filter water
affect weather
provide food or fuel
provide wood and fibre
How much of Canada’s water originates in forests?
~80%
Give an example of how forests affect weather
the Amazon rainforest affects weather in other regions
How many people globally rely on forests for food and fuel?
more than 1.6 billion
How many hectares of forest have been lost from 1990-2020?
~420 million ha
What is an example of how an area can be rapidly regaining forest coverage?
through forest plantations
ex. China has a reforestation program
What continents of the world have seen net gains in forest area (hectares/year) in the last 3 decades?
Asia
Oceania (in the last 10 years)
Europe
Minimally in N and Central America from 2000-2010
What continents of the world have seen net losses in forest area (hectares/year) in the last 3 decades?
South America + Africa have experienced major net losses
Oceania and N and C America some
What are 3 things that define a forest?
administrative purposes (legal designations)
land use (purpose of land)
land cover (density of trees)
What 2 features do land cover definitions of forests depend on?
tree height (ex. trees are over 5m)
tree cover (ex. forests have over 10%)
What height defines a tree according to the land cover definition?
> 5m are trees
< 5m are shrubs
What % of tree cover defines a forest according to the land cover definition?
> 10% tree cover over the area
How much of BC is designated as forest? How accurate is this?
85% is designated as forest, but not all of that area is actually forested (ex. mountains, water)
How does the % tree cover definition change the distribution of forested areas globally as it increases?
10% of tree cover includes a lot of the planet (4 billion ha)
vs
50% tree cover includes a more accurate area (2.5 billion ha)
vs.
75% tree cover includes a lot less of the planet
Which % tree cover is probably most accurate definition of the planet’s forested areas?
50% = 2.5 billion ha
A forest includes trees of what minimum height?
min 5m
How can the degree of human disturbance affect the description of forests?
primary forests
vs
secondary forests
vs.
plantations
these classifiers change the definition of a forest
What 10 countries have the largest forest area (when considering all forest definitions)?
Russia
Brazil
Canada
US
China
Australia
DR of Congo
Indonesia
India
Peru
How does changing the definition of forests to primary forests change the countries with largest area?
Some new countries on the list and some of the countries with large forested areas removed from list
Brazil
Russia
Canada
US
Peru
Indonesia
Colombia
Mexico
Bolivia
Papua New Guinea
Note that China, India, Australia and Congo not on this list
What does ecology mean? What are the word origins? and what is the most encompassing and accurate definition?
Oikos (Greek) = home/house
logia (Greek) = study
Ecology = ‘the scientific study of the abundance, dynamics, and distribution of organisms and their interactions with their biotic and abiotic environment’
What are the major elements of the definition of ecology?
abundance
dynamics
distribution
interactions of organisms with both living and non-living components of their environment
How does the definition change for forest ecology?
it specifies that the organisms are forest organisms
otherwise the same
What is the objective goal of forest ecology?
‘to study what controls the patterns of distribution and abundance of different organisms in forests of the world’
What is the ecological hierarchy from least to most complex (top to bottom)?
individual
population
community
ecosystem
landscape
biome
biosphere
What makes it challenging to define each structure in the ecological hierarchy?
the increasing complexity with each level makes the lines/boundaries blurry
Define an ecological population
a group of individuals from the same species that interact with the same environment
What is a metapopulation?
2+ populations of the same species that experience gene flow
What is an ecological community?
a group of interacting species (ex. a forest has trees, shrubs, annals, soil organisms)
What is an ecological metacommunity?
a group of local communities connected by the dispersal of multiple potentially interacting species (ex. gene flow, organisms, resources)
what is the difference between a population and a metapopulation?
a population is one group of a single species that interact with each other and the same environment
vs.
a metapopulation is 2+ populations (of the same species) that exchange genes
what is the difference between a metapopulation and a metacommunity?
a metapopulation is 2+ populations that interact via gene exchange
whereas,
a metacommunity is a group of communities (populations of different species) that are linked by multiple interacting species
Define an ecosystem
a community + the environmental and physical (ie., abiotic) factors and forces acting on it
basically, the communities of organisms + the physical, abiotic environment
What is a metaecosystem?
a group of ecosystems that are connected by the flow of energy, materials, and organisms
What is a landscape? what is an example?
an area of land or water that is made up of multiple ecosystems (ex. a watershed)
What are the 2 major differences between metaecosystems and landscapes?
metaecosystems are a group of interconnected ecosystems that experience exchanges of energy, material, and organisms
landscapes are an area of land with multiple ecosystems
metaecosystems are:
- MASS-CONSERVING (ie., no resource input/output, just continued cycling)
- can be SPATIALLY DISCONNECTED (ex. islands)
landscapes are:
- NOT mass-conserving (ie., there’s a dispersal of resources - inputs + outputs)
- SPATIALLY CONTINUOUS