ECOLOGYOrganisms and Their Environment

VOCABULARY

Ecology – study of interactions that take place b/t organisms and their environment

Abiotic factor – non living parts of an organisms environment (i.e. rocks, air currents)

Biotic factor – all living organisms that inhabit an environment (including things that are dead but were once living)

Biosphere – portion of Earth that supports living things

VOCABULARY

Food web – shows all possible feeding relationships at each trophic level in a community

Trophic level – each organism in a food chain representing a feeding step in the passage of energy and materials

Mutualism – symbiotic relationship in which both species benefit

Commensalism – symbiotic relationship in which one organism benefits and the other is unaffected

VOCABULARY

Parasitism – symbiotic relationship in which one organism benefits and the other organsims is harmed

Symbiosis – relationship in which 2 organsisms live closely together

Biodiversity – variety of life in an area, usually measured by the # of species

Niche – all the strategies and adaptations a species uses in its environment; how it meets its specific needs for food and shelter; how it survives; where it reproduces

VOCABULARY

Habitat – place where an organism lives out its life

Food chain – simple model that scientists use to show how matter and energy move through an ecosystem

Producer – organism that make organic molecules from inorganic molecules; serve as a food source for other organisms (i.e. plants)

VOCABULARY

Consumer – organism that eats other organisms or organic matter instead of producing its own nutrients or obtaining nutrients from inorganic sources (i.e. rabbits, deer, humans)

Decomposer – organism that feeds by breaking down organic matter from dead organsims (i.e. bacteria, fungi)

THE BIOSHPERE

Earth – the planet we live on (duh!) Divided into different parts

Lithosphere – Earth’s crust Hydrosphere – Earth’s water in all forms Biosphere – contains all life Atmosphere – all of Earth’s air

Biosphere overlaps/encompasses some or all of each of the other spheres

BIOSPHERE

Consists of all living –biotic factors, and non living –abiotic factors

Abiotic factors are necessary to sustain life Air currents Temperpature Moisture Light Soil, rocks

ABIOTIC FACTORS

Affect the environment i.e. amount of rain fall determines the

abundance & diversity of life an area can support

Whale page 37 Problem-Solving Lab 2.1

BIOTIC FACTORS

Biotic factors affect the abundance and diversity of life in an area as well Competition among species Symbiotic relationships

ORGANIZATION OF THE BIOSPHERE (WHALE 40)

In order from smallest to largest: Organism Populations Community

Ecosystem Biosphere Organism: single individual of a species Population: species of organism that lives

in the same place at the same time Community: all populations living in the

same place at the same time Ecosystem: biotic and abiotic factors in

the same place at the same time

ORGANISMS IN AN ECOSYSTEM

Each organism has its own habitat i.e. Birds may live in trees; centipedes live on the

ground Each organism has its own niche

Different species may share habitats, food, shelter There will be at least one essential resource that will

be used in a different way by each organism Leads to reduced competition for resources If 2 species use the same resources, eventually one

will gain control and the other will die off or migrate

SYMBIOSIS - MUTUALISM

SYMBIOSIS - COMMENSALISM

SYMBIOSIS - PARASITISM

ENERGY FLOW THROUGH AN ECOSYSTEM

How organisms obtain energy: Producers – make their own Primary Consumers – only eat producers

(herbivores) Secondary consumers – eat primary consumers

(carnivore), sometimes producers as well (omnivores)

Tertiary consumers – eat secondary consumers, sometimes eat producers as well

Decomposers – eat decomposing producers and consumers

ENERGY FLOW IN AN ECOSYSTEM

Food chain Follows the flow of energy as it moves

through organisms i.e. Seaweed perch shark sea slug As food moves through the chain, the

amount of energy passed to each level diminishes considerably (Whale 52)

ENERGY FLOW THROUGH AN ECOSYSTEM Food web – encompasses all the food

chains in an ecosystem (Whale 51-52) Problem Solving Lab 2.2 on Whale 50

AFFECTS ON BIODIVERSITY

Changes in an ecosystem can affect its biodiversity

What would happen if it stopped raining in the Mojave Desert? Or, if the amount of acid in the rain falling in the Sierra Nevada Mts increased dramatically to lethal levels?

Whale page 51

AFFECTS ON BIODIVERSITY

Uncontrolled population growth of a single species can affect biodiversity

Humans as a species can have a devastating affect on biodiversity i.e. hunting to extinction the grey wolves in Yellowstone

Non native/alien/invasive/introduced species can affect the biodiversity Usually have no natural predators so they can flourish

in the new area & dominate the resources, leaving little resources for the native species which do have natural predators

CYCLES IN NATURE

Water cycle – precipitation evaporation / transpiration condensation Process recycles water through the

environment Carbon cycle – all life on Earth is based

on carbon They form all biological molecules (protein

etc) Plants use CO2 to make food consumers

exhale CO2 back to the atmosphere for plants to use

CYCLES IN NATURE

Nitrogen cycle – plants need nitrogen to produce Plants get nitrogen from soil & turn it into

food consumers eat plants & store nitrogen in their bodies, then release as urine or they die and are decomposed and the nitrogen returns to the soil

LIFE W/IN COMMUNITIES

Limiting factors – any biotic or abiotic factor that restricts the existence, numbers, reproduction, or distribution of organisms i.e. availability of food & water, predators,

temperature, climate Tolerance – the ability of organisms to

w/stand fluctuations in biotic and abiotic factors

LIFE W/IN COMMUNITIES

Succession – change over time Primary succession: colonization of barren

land by communities of organisms Takes place where there is no life i.e. lava fields Pioneer species – 1st species to take hold, they

eventually die, but they change the land so other species can thrive

Climax community – the stable, mature community that undergoes little/no change in species following primary succession

LIFE W/IN COMMUNITIES

Secondary succession – sequence of changes that takes place after an existing community is severley disrupted in some way Compare to primary – primary is barren

land w/ no life, secondary is some life but largely devastated

i.e. fire devastated areas, some life will still exist, but most of it will have been wiped out

BIOMES

Biome – large group of ecosystems that share the same type of climax community

Divided into terrestrial and aquatic Organisms w/in each are adapted to

the conditions of that particular biome

AQUATIC BIOMES

Marine/Ocean, divided into zones Photic zone: portion shallow enough for

sunlight to penetrate, photosynthesis can occur

Aphotic zone: deep waters that never receive sunlight, photosynthesis cannot occur

AQUATIC BIOMES – PHOTIC ZONES

Intertidal zone (tide pools) Close to shore line Organisms are adapted to periodic

exposure to air during low tide times Types of organisms: crab, mussels,

oysters, sea anemones, sea stars Organisms must be able to w/stand

crashing waves

TIDE POOLS

PHOTIC ZONES

Neritic Zone Extends from intertidal zone over the

continental shelf Most productive marine zone Upwellings carry nutrients from ocean

bottom Species: plankton, numerous fish, sea

turtles

PHOTIC ZONES

Neritic Zone – Coral Reefs Form in tropical neritic areas Rich in species Built by coral animals over long periods of

time Constructed by their external skeletons, as

animals die, the skeletons acculuate Species: fish, crustaceans, mollusks, etc

NERITIC ZONE

AQUATIC BIOMES – PHOTIC/APHOTIC ZONES

Oceanic Zone The upper portion of the oceanic zone is

photic The lower portion (deep ocean) is aphotic Contains fewer species than the other

zones, even in the photic zones Species in upper portion –

Producers: microscopic protists, bacteria, plants, invertebrate plankton

Animals: fish, mammals like whales, large invertebrates

OCEANIC ZONE

Aphotic zone Species feed on sinking plankton & dead

organisms Deep ocean – near freezing temps &

crushing pressure Species have slow metabolisms & reduced

skeletal systems, large jaws & teeth, expandable stomachs

Species: squid, by thermal vents – clams, crabs, worms

OCEANIC ZONES

AQUATIC BIOMES - ESTUARIES

Where freshwater meets sea i.e. bays, mud flats, mangrove swamps, salt

marshes Shallow water gets lots of sunlight & rivers deposit

lots of minerals Interaction of fresh and salt water causes great

variation in temp and salinity Surface is exposed to air during low time Organisms are adapted to frequent change Species: mangrove trees, softshell clams,

plankton, snails, shrimp, crab, grasses and trees

ESTRUARIES

AQUATIC BIOMES - FRESHWATER

Lakes and ponds Eutrophic lakes – rich in organic matter and

vegetation, waters are murky Oligotrophic lakes – contain little organic

matter, water is clearer, bottom usually rocky or sandy

Species – fish, ducks, turtles, snakes, salamanders, frogs

AQUATIC BIOMES - FRESHWATER

Rivers and streams Body of freshwater that flows downward Organisms are adapted to strong currents Slow-moving rivers are richer in nutrients

& support greater diversity of life, rooted plants

Species: brook trout and other fish

AQUATIC BIOMES - FRESHWATER

Freshwater wetlands Land covered w/ fresh water at least part of each year Marshes – non woody plants (cattails) Swamps – woody plants (trees/shrubs) Bog – sphagnum mosses Most productive freshwater biomes Species – birds, fish, mammals, amphibians,

invertebrates, reptiles, whooping crane, Florida panther, american crocodile, american alligator

Provide protection for spawning organisms Filter pollutants out of the water & act as flood control

AQUATIC BIOMES - FRESHWATER

TERRESTRIAL BIOMES - TUNDRA

Temp: -14.8 F to 53.6 F Precipiation: <25 cm Soil: moist, thin topsoil over permafrost;

low in nutrients; slightly acidic Vegetation: mosses, lichen, grasses,

dwarf woody plants Animals: arctic fox, caribou, ermine,

grizzly bear, harlequin duck, musk ox, polar bear, snowy owl

TUNDRA

TERRESTRIAL BIOMES – TAIGA

Temp: 14 F to 57.2 F Precipitation: 35-75 cm Soil: low in nutrients; highly acidic Vegetation: coniferous evergreen trees Animals: American black bear, bald

eagle, bob cat, Canadian lynx, grey wolf, grizzly bear, long eared owl, red fox, river otter, snowshoe rabbit, wolverine

TAIGA

TERRESTRIAL BIOMES – FORESTS: TEMPERATE FOREST

Temp: 42.8 F to 82.4 F Precipitation: 75-125 cm Soil: moist, moderately thick topsoils;

moderate nutrient levels Vegetation: broad-leaved deciduous trees and

shrubs or evergreen coniferous trees Animals: American bald eagle, American black

bear, coyote, duckbilled platypus, eastern chipmunk, European red squirrel, fat dormouse, least weasel, white tailed deer

TEMPERATE FOREST (DECIDUOUS FOREST)

TERRESTRIAL BIOMES – FORESTS: TROPICAL FORESTS

Temp: 68 F to 93.2 F Precipitation: 200-400 cm Soil: moist, thin topsoil; low in nutrients Vegetation: broad-leaved evergreen trees and

shrubs Animals: African forest elephant, Bengal tiger,

chimpanzee, common palm civet, dawn bat, golden lion tamarin, harpy eagle, jambu fruit dove, king cobra, kinkajou, Linn’s sloth, orangutan, probiscus monkey, red shanked douc

TROPICAL FORESTS

TERRESTRIAL BIOMES – GRASSLANDS: TEMPERATE GRASSLANDS

Temp: 32 F to 77 F Precipitation: 25-75 cm Soil: deep layer of topsoil; very rich in nutrients Vegetation: dense, tall grasses in moist areas;

short grasses in drier areas Animals: corsac fox, Mongolian gerbil, saiga

antelope, northern lynx, saker falcon, American bald eagle, badger, bob cat, bumble bee, prairie dog, swift fox, Geoffrey’s cat, greater rhea

TEMPERATE GRASSLANDS

TERRESTRIAL BIOMES – GRASSLANDS: SAVANNA

Temp: 60.8 F to 93.2 F Precipitation: 75-150 cm Soil: dry, thin topsoil; porous; low in

nutrients Vegetation: tall grasses and scattered

trees Animals: African elephant, African wild

dog, black mamba, caracal, chacma baboon, Egyptian mongoose, emu, Grant’s zebra, koala bear, lion, nigriceps ants, nile crocodile

SAVANNA

TERRESTRIAL BIOMES – GRASSLANDS: CHAPARRAL

Temp: 50 F to 64.4 F Precipitation: <25 cm Soil: rocky, thin topsoil; low in

nutrients Vegetation: succulent plants and

scattered grasses Animals: aardwolf, black tailed jack

rabbit, cactus wren, golden jackal, grey wolf, island grey wolf, puma, spotted skunk, wild goat

CHAPARRAL

TERRESTRIAL BIOMES - DESERTS

Temp: 44.6 F to 100.4 F Precipitation: <25 cm Soil: dry, often sandy; low in nutrients Vegetation: succulent plants and scattered

grasses Animals: armadillo lizard, banded gila

monster, bob cat, cactus wren, coyote, desert bighorn sheep, desert kangaroo rat, desert tortoise, javelina, cactus, ferruginoug pygmy owl, thorny devil

DESERT