2c. Pacific Maritime Ecoregion - intertidal, stream, forest

intertidal zone: a narrow strip of coastline that is alternately immersed in seawater and exposed to air, according to the rise and fall of the tide

estuary: tidal mouth of a large river, where the tide meets freshwater

keystone species: an organism that has a disproportional influence on the rest of the ecosystem

epibiotics: living on the surface of another organism

stream: a generic term to describe watercourses of all sizes that have channels of running water

perennial: always running

ephemeral: no stream in summer

headwaters: stream with no perennial running tributaries

riparian zone: ecotone between land and stream

autochthonous production: in stream primary production by algae and plants

allochthonous production: primary production that is derived from outside the aquatic environment

indicator species: species with rigorous environmental demands

epiphytes: organism that grows upon or attaches to a living plant

biogeoclimatic zones: an area with a relatively uniform macroclimate and characterized by the climax vegetation

succession: the gradual change in the species that occupy a given area following a disturbance

primary succession: succession on newly exposed retreat

secondary succession: succession after a disturbance has destroyed the plant community, but soil remains intact

site capability: the potential of the land to sustain its productivity

snags: dead/dying trees

DBH: diameter at breast height

Tides

  • when moon is in line with the earth and sun, extreme tides
  • when moon is perpendicular to earth, modest tides
  • lowest areas only exposed for a few moments during the most extreme tides

Intertidal Zone

  • intertidal animals = marine and require salt water for essential biological functions
  • intertidal zone is narrow but hella long
  • hella zonation
    • many classic studies done in intertidal because of zonation
  • diversity tends to increase in lower intertidal zones
  • any exposed surface is rapidly colonized
  • epibiotics = common
  • plankton = food for intertidal ecosystem
  • tide pools experience great fluctuations in temp
  • sandy beaches/mudflats support a diff community
    • nothing to hang onto
    • most life hidden within the sand

Estuary

  • plant and animal communities adapted to brackish water
  • productive ecosystem = migration stopover for birds

Joseph Connell

  • barnacle experiments
  • elaborate
    • fundamental niche
    • what you can take up
    • realized niche
    • what you can take up including effects of other organisms

Robert Paine

  • sea star experiment
  • sea star = keystone species

Stream Ecology

  • know how to calculate stream order
  • ecotone has different plants, soil, and microclimate
  • riparian zones are obvious in arid climate
  • less obvious in temperate rainforests
  • in headwaters, allochthonous production is more important
River Continuum Concept
  • headwaters to large river systems
  • allochthonous to autochthonious
  • CPOM to FPOM(course particulate matter to fine particulate matter)
  • macroinvertebrates are shredders to collectors
EPT
  • ephemeroptera = mayflies
  • plecoptera = stoneflies
  • trichoptera = caddisflies
  • all indicators of good quality water

Temperate Rainforests

  • typically coniferous forests that occur in temperate zones and receive high amount of rainfall
  • definition
    • annual precipitation over 1400 mm
    • mean annual temperature between 4-12 degrees celcius
    • closed canopy of trees excludes at least 70 percent of sky
    • forest composed of tree species that do not require fire for regeneration
    • among rarest biomes of earths land
    • much already logged
  • typically close to ocean
  • coastal mountains
  • summer fog
  • hella epiphytes
  • sustains highest level of biomass of any terrestrial ecosystem
    • 500-2000 metric tons / hectare
    • due to massive trees
  • North America has largest area of temperate rain forests on the planet
    • Southern Alaska to Northern California
    • BC alone has about 25 percent of remaining temperate rainforest
  • 380 vertebrate species occur in narrow band of coastal temp rain forest in North America

Biogeoclimatic zones

  • diff trees occupy diff zones
  • Douglas-fir and Western Red Cedar indicate wet
  • Arbutus indicates dry
  • Garry Oak indicated meadow
Coastal Douglas-fir
  • one of the smallest zones
  • in the rain shadow of Vancouver Island = long, dry summers
Coastal Western Hemlock Zone
  • lower elevations (<900 m) west of the Coast Mountains
  • extends along major river valleys
Mountain Hemlock Zone
  • subalpine elevations (>900m) along the entire coast
  • between the densely forested Coastal Western Hemlock Zone and the treeless Alpine Tundra Zone
  • nutrients are quickly leached out of local soils why?

Succession

  • when trees are harvested, large amounts of nutrients are also removed, leading to much slower growth rates
    • leads to loss of site capability
  • disturbing the forest can increase nutrient leaching, when nutrients are transported downward into the soil with percolating rainwater
  • snags provide nesting, feeding, and perching sites

Forest Fires and Wildlife

  • putting them out used to be the only response
  • fire is a natural process tho

Forestry Techniques

  • DBH tape is used to determine the diameter of a tree
  • Abney level is used to determine the height of trees
  • increment corer is used to obtain tree cores, which can be used to determine tree age and rate of growth
Quadrats
  • sampling standardized area
  • intertidal zone
    • 30 cm x 30 cm
    • 1 m x 1 m
  • forest trees
    • 10 m x 10 m
    • 25 m x 25 m
    • 10 m radius
Sampling
  • must be random
  • standardized
  • replication is must
Mountain Pine Beetle
  • one of three major bark beetles in BC
  • native of the forest ecosystems
  • kills Lodgepole Pine
  • largest forest insect infestation
  • strike during July and August when trees are often stressed from dry conditions
  • females fly to new trees and bore through the bark
  • damage is caused by construction of egg galleries and beetle larvae
    • eat cambium and phloem
  • flow of water and nutrients cut off? trees die
  • adult beetles also deposit fungus that further reduce the tree’s defence
Why the outbreak?
  1. Climate change
    • reduction in sustained, extreme cold
    • mild winters have decreased the winter mortality
  2. for the last 70 years, forest fires have been suppressed
    • unintended consequence = extensive areas of mature trees
    • mature trees = more susceptible to beetle attack

Environmentalists’ Take

  • logging companies took advantage of this idea and logged more trees
    • increase the probability of future outbreaks by creating even-aged stands