Introduction to the Marine Environment
Chapter 1
Data
71 % of Earth is salt water
average water depth 3.8 km
volume of 1,370 x 106 km 3
ocean largest repository of organisms
adapt to seawater to survive
terminology important to understand the text
Properties of Water
Marine plants and animals bodies composed of water
medium for chemical reactions inside and outside the organisms body
Chemical composition
H2O
bonded asymmetrically
Oxygen at one end and 2 hydrogen at the other end
Polar, H +, O -, unique chemical and physical properties
Covalently bonded
Easily broken and reformed
This is why it is a gas, liquid or solid
Properties of Water
Physical
cohesion - stick to itself
surface tension
viscosity
temperature and salinity
heat of vaporization is high latent heat of fusion
high heat capacity
ice lighter than water
density differences responsible for deep ocean currents
Chemical
solvent capacity
almost a universal solvent
2 types
polar character of the molecule
hydrogen bonding
salt ions
H+ and OH -
Seawater
Salinity
parts per thousand
new term, psu - practical salinity units
35 g dissolved compounds in 1,000 g
table 1.2, page 5
inorganic salts, organic compounds
differences in evaporation and precipitation
gases distributed
oxygen minimum zone
acidity
alkaline ( basic )
Carbon dioxide - carbon acid - bicarbonate = buffer
Basic Oceanography
To understand the ecology of various marine associations, it is necessary to know something about the structure and motion of the ocean water masses.
Geography and Geomorphology of the Oceans
Four major divisions
Pacific, Atlantic, Indian, Arctic
Figure 1.5, page 8
81 % of southern Hemisphere
61 % of Northern Hemisphere
continental shelf
continental slope
abyssal plain, figure 1.6, page 8
submarine ridges
mid-Atlantic ridge
islands - Azores, Ascensions, Tristan da Cunha
trenches - 7,000 - 11,000 m in depth
deepest 11,022 m Challanger Deep in the Mariana Trench
seamounts - isolated volcanic action
Plate Tectonics
1960
plates
figure 1.7, page 9
continental drift
oceanic ridges are center of volcanic activity
seafloor spreading
subduction
hydrothermal vents
site of unique deep-sea organisms
discovered in 1977
Temperature and Vertical Stratification
Metabolism
above and below their limits
poikilothermic or ectithermic
homeothermic or endothermic
four major biogeographical zones
polar
cold temperate
warm temperate ( subtropical )
tropical ( equatorial )
thermocline
pycnocline
Water Masses and Circulation
Upper water mass
deep water mass
waves and currents
wavelength
period
tsunamis
tides
speed
fetch
duration
Coriolis effect
gyres
Ekman spiral
Some Ecological Principles
Ecology
species
population
community
ecosystem
smaller sections
Ecosystem components
Autotrophic
heterotrophic
trophic structure
trophic level
herbivores
carnivores
omnivores
standing crop
decomposers
food chain
food web
Biogeochemical Cycles
Cycling back and forth
carbon cycle
nitrogen cycle
phosphorous cycle
figure 1.17, page 19
Biotic Structure of Ecosystem
Niche
fundamental niche
realized niche
habitat
dominants
species richness
species diversity
Leibig’s law of the minimum
Limiting factors
ecotone
ecological succession
climax
seres
facilitation model
inhibition model
tolerance model
Ecological control and regulation
Tolerance limits
competition
competitive exclusion principle
predation
grazer
key industry
keystone species
parasites
Larval Types and Strategies
Planktotrophic larvae
lecithotropic larvae
nonpelagic or direct development
non-pelagic larvae or juveniles
figure 1.18, page 23
advantages and disadvantages
Larval Ecology and Community Establishment
Figure 1.19, page 26
pheromone
D. P. Wilson 1952
Thorson 1966
Butman 1987
different species have different times of reproduction
places to settle change from year to year
Life History Strategies
Opportunistic or r selected
sessile ( fixed in place )
equilibrium or K selected
table 1.3, page 27
bottom disturbed - opportunists
figure 1.20, page 28, next page
Comparison of Terrestrial and Marine Ecosystems
Physical and Chemical differences
filter feeders
gravity
Biodiversity Differences
Life History Differences
Structural and Functional Differences
copepods
Division of the Marine Environment
Major Subdivisions of the World Ocean
pelagic
benthic
neritic
oceanic
photic or eutrophic
epipelagic
aphotic
disphotic
mesopelagic
bathypelagic
Abyssalpelagic
hadalpelagic
bathyal
abyssal
hadal
sublittoral or shelf
intertidal or littoral
Estuaries
Summary of Key Concepts
Study them on pages 34 - 35
Answer the Review Questions on page 35 # 1, 2, 3, 4
Answering these questions will take some time and energy. Expect long and specific answers.