Physical environment comprises temperature, wind, moisture, salinity, pH, fire.

1
Physical environment comprises temperature, wind,
moisture, salinity, pH, fire.

• Physical environment is strong influence on
  biological distributions and processes

2
Earths shape, axis of rotation, and revolution
around the sun each year, as well as physical
properties of earth, air, and water determine
general patterns of climate and the physical
environment organisms inhabit.
3

• The shape of the earth influences the amount of
  insolation different areas of the earth receive
• Shape of earth also influences the direction of
  winds and currents
• Earths axis of rotation and revolution around
  sun affect seasonality of weather patterns.
• Physical properties of air, land, and water
  influence movement of air masses and rainfall in
  particular regions

4

• The shape of the earth influences the amount of
  insolation different areas of the earth receive
• Shape of earth also influences the direction of
  winds and currents
• Earths axis of rotation and revolution around
  sun affect seasonality of weather patterns
• Physical properties of air, land, and water
  influence movement of air masses and rainfall in
  particular regions

5
Coriolis effect

• The deflection of wind or water due to the
  earths rotation

6
Problem

• If a mass of air is moving from 30 degrees south
  up toward the equator, which way will the wind be
  deflected?

7
Problem

• If a mass of air is moving from 30 degrees north
  up toward 60 degrees north, which way will the
  wind be deflected?

8
Winds create currents
9

• The shape of the earth influences the amount of
  insolation different areas of the earth receive
• Shape of earth also influences the direction of
  winds and currents
• Earths axis of rotation and revolution around
  sun affect seasonality of weather patterns
• Physical properties of air, land, and water
  influence movement of air masses and rainfall in
  particular regions

10
Equinox

• Either of two times of year (March 21 and
  September 22) when the sun and Earths positions
  are such that day and night are exactly 12 hours
  everywhere on Earth

11

• The shape of the earth influences the amount of
  insolation different areas of the earth receive
• Shape of earth also influences the direction of
  winds and currents
• Earths axis of rotation and revolution around
  sun affect seasonality of weather patterns
• Physical properties of air, land, and water
  influence movement of air masses and rainfall in
  particular regions

12

• Warm air holds more water and is less dense than
  cold air, therefore rain results from the cooling
  of moist air
• High specific heat of watermore heat energy is
  needed to change the temperature of a given
  amount of water compared to a given amount of land

13

• Patterns of air movement and temperature
  influence where wet and dry areas are found

14
Biomesmajor ecological zones corresponding to a
climatic zone with a typical vegetation
structure, for example, temperate deciduous
forest, desert, tropical savanna

• Biomes are distinct from biogeographic regions

15
Smaller-scale (regional) patterns of physical
factors within the larger patterns

• Urban areas are much warmer than surrounding
  areas within a biome
• Mountains influence climate by influencing
  moisture patterns

16
Physical factors on a very fine scale

• Wind and nest orientation
• Temperature will vary above and below ground
• Temperature, salinity, and moisture levels all
  change drastically from low tide to high tide in
  the intertidal zone

17
Aquatic environments
18
Important property of waterwater is densest at
4ºC

• Ice floats
• Warm water stays above cool water
• Salty water is denser than less salty water

19
Thermoclinethe boundary layer in the water
between surface warmer waters and deeper, cooler
waters, where the temperature gradient is greater
than that of the warmer layer above and the
colder layer below.
20
Thermal stratification

• Stable in tropics year-round
• Upper waters are warm, well-lit and oxygen-rich
• Lower waters are cold, dark, and oxygen-poor

• Overturn occurs at higher latitudes
• Oxygen is brought to lower levels and nutrients
  are brought to upper levels

21
Overturn

• Vertical mixing of the water column in a lake
  caused by temperature changes over the seasons

22

• Overturn in temperate lakes means they tend to be
  quite productive (produce biomass), compared to
  tropical lakes

23
Oceans--make up nearly three quarters of the
surface of the earth but their boundaries are
less clear-cut than those of the landmasses
24
Differences between terrestrial and oceanic
environments

• Major oceans are connected, unlike the continents
• Water is constantly moving and moves organisms
  with it
• Temperature, light, and other environmental
  gradients along the horizontal axis tend to
  change more smoothly and gradually than on land
• Depth--environmental gradients may be quite steep
  along the vertical axis
• Plants do not provide physical structure in the
  oceans

25
Thermal and solar stratification

• Anchored plants only near surface
• Deep water is very cold

26
Oceanic biomes

• Arctic
• Subarctic
• Northern Temperate
• Northern Subtropical
• Tropical
• Southern Subtropical
• Southern Temperate
• Subantarctic
• Antarctic

27
Vertical classification of oceanic areas

• Continental shelf
• Continental slope
• Abyssal plain
• Trenches

28
Water circulates horizontally in the oceans

• Coriolis effect causes wind patterns which cause
  currents or gyres.
• Current primarily flows clockwise in northern
  hemisphere and counter-clockwise in southern
  hemisphere
• Continent of Antarctica is enclosed by cold,
  eastward flowing waters.
• Indian Ocean has complex current patterns because
  of seasonal wind direction shift

29
Water also circulates vertically in the oceans

• In polar regions there is bottom water
• In North Atlantic and Pacific, evaporation leads
  to convergences
• Winds and upwelling
• Water also rises in areas of divergences

30
Complete vertical circulation takes 275 years in
Atlantic, 250 years in Indian Ocean, and 510
years in Pacific
31
We know little about marine organisms

• Census of marine life
• Our knowledge of distributions of marine
  organisms tends to be more primitive than for
  terrestrial organisms

32
Areas of upwellings are areas with rich fisheries
33
Fishery

• A place for catching fish
• Also, the occupation, industry, or season of
  catching fish (or other sea creatures)

34
Most of the largest fisheries are based on small
fish like sardines and anchovies

• Nutrient-rich areas (often associated with
  upwellings) like the coasts of California, Japan,
  South Africa, Chile, and Argentina have very
  productive fisheries in some years

35
The productivity of these fisheries fluctuates
dramatically over time

• Catches may be huge for a decade or two and then
  collapse and reappear 1-3 decades later

36
Global warming and cooling affect productivity,
perhaps through affects on food sources

• Anchovies eat large zooplankton
• Sardines eat small zooplankton and phytoplankton

37
Differences in mobility affect species ability
to respond to climate change

• Some species of sardines are migratory and can
  move toward the poles during warmer periods
• Some species of anchovies are not as mobile

38
Hunting pressure also contributes to declines

• Anchovies used for human consumption
• Anchovies also used to provide fish meal for
  aquaculture systems

39
How do we determine distributions of marine
organisms?

• ExampleMesoplodon spp. or beaked whales

40
Stranded specimens

• Sick animals may not behave normally
• Carcasses may be pushed great distances
• Identification of carcasses may be difficult