Hit Counter

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.

Back to:  Notebook