Environmental Science 1021F/G Lecture Notes - Arctic Cordillera, Commensalism, Parasitism

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ES1021F Lecture 4 October 5, 2011
Previous date’s notes were also presented today.
Biodiversity - Summary
Biomes and Ecozones
Earth’s major biomes and their characteristics
A biome is a geographically extensive ecosystem, occurring wherever environmental
conditions are suitable for its development
Biomes are not characterized by their species – it is the dominant life forms that identify
them
At far-flung parts of biomes, different species may dominate the ecosystem
They may not even be closely related, but are similar in form and function because of
convergent evolution
Earth’s major biomes ()
The occurrence of biomes is determined by the environmental regime in which they
develop
ES1021F Lecture 4 October 5, 2011
Terrestrial biomes are primarily influenced by temperature and precipitation
Freshwater biomes are mostly affected by nutrient availability, water transparency, and
depth
Marine ones biomes are affected by nutrients and physical oceanography
Earth’s major biomes ()
Major terrestrial biomes: EXAM! !!! !!! !!! !! ^^^
Tundra – vegetation of short stature, occurring at high latitude (arctic) and high altitude
(alpine)
Boreal forest – northern subarctic forest, usually dominated by coniferous trees
Montane forest – a subalpine analogue of the boreal (boreal forest but on mountain)
Temperate forest – angiosperm-dominated forest deciduous trees of intermediate
latitudes
Temperate rainforest – old-growth coniferous forest in a high-rainfall climate
ES1021F Lecture 4 October 5, 2011
Temperate grassland – short-, mixed-, and tall-grass prairie types are limited by soil
moisture
Desert – sparsely vegetated because of dry conditions
Tropical forest – various kinds of low-latitude forests in a warm, humid climate and
supporting extremely rich biodiversity
Earth’s major biomes ()
Freshwater biomes:
Lentic – lakes and ponds, not flowing water, any water that isn’t moving around all the
time
Lotic – rivers and streams, moving fast, flowing quickly
EXAM!!!!!!!!!! :
Difference between lentic and lotic?! Or difference between lentic and lotic system?
Wetlands (or mires) – shallow, continuously or seasonally wet habitats
Land that is really wet……
Marsh – highly productive and dominated by reed, cat-tail, bulrush, or other tall
graminoids
Swamp – productive and dominated by tall shrubs or trees
Bog – unproductive and dominated by peat mosses
Fen – moderately productive and dominated by sedges and mosses
Open-water wetland – moderately productive and dominated by aquatic plants
Earth’s major biomes (productivity is governed by biomass/vegetation in a biome)
EXAM!!!!!!: Difference between biomes and Eco zones?
Marine biomes:
The open ocean – deep waters and highly unproductive – a marine desert
Continental Shelf Waters – moderate depths (up to several hundred metres) and
moderate fertility and productivity
Persistent upwellings – regionds of high fertility and high productivity
Estuaries – semi-enclosed coastal ecosystems with high productivity
Seashores – productive intertidal and shallow subtidal ecotonal habitats occurring
between true terrestrial and marine ones
Coral reefs – infertile but highly productive and biodiverse tropical ecosystems
Earth’s major biomes ()
Human-dominated ecosystems: