Succession in Ecosystems

SOL BIO 9c

What do you mean by environment?The environment is made up of

two factors:

Biotic factors- all living organisms inhabiting the Earth

Abiotic factors- nonliving parts of the environment (i.e. temperature, soil, light, moisture, air currents)

Habitat vs. Niche

Niche - the role a species plays in a community (job)

Habitat- the place in which an organism lives out its life (address)

Habitat vs. Niche

A niche is determined by the tolerance limitations of an organism, or a limiting factor.

Limiting factor- any biotic or abiotic factor that restricts the existence of organisms in a specific environment.

Examples of limiting factors-

•Amount of water•Amount of food•Temperature

Habitat vs. Niche

Symbiotic Relationships

Symbiosis- two species living together

3 Types of symbiosis:

1. Commensalism

2. Parasitism

3. Mutualism

Symbiotic Relationships

Commensalism- one species benefits and the other is neither harmed nor helped

Ex. orchids on a tree

Epiphytes: A plant, such as a tropical orchid or a bromeliad, that grows on another plant upon which it depends for mechanical support but not for nutrients. Also called aerophyte, air plant.

Symbiotic RelationshipsCommensalism-

one species benefits and the other is neither harmed nor helped

Ex. polar bears and cyanobacteria

Symbiotic RelationshipsParasitism- one species benefits (parasite)

and the other is harmed (host)

Parasite-Host relationship

Symbiotic RelationshipsParasitism- parasite-hostEx. lampreys, leeches, fleas,ticks,tapeworm

Symbiotic RelationshipsMutualism-

beneficial to both species

Ex. cleaning birds and cleaner shrimp

Symbiotic RelationshipsMutualism-

beneficial to both species

Ex. lichen

Type of relationship

Species harmed

Species benefits

Species neutral

Commensalism

Parasitism

Mutualism

= 1 species

Succession-

a series of changes in a community in which new populations of organisms gradually replace existing ones

Primary succession-

colonization of new sites by communities of organisms – takes place on bare rock

Primary succession-

New bare rock comes from 2 sources:

1. volcanic lava flow cools and forms rock

Primary succession-

New bare rock comes from 2 sources:

2. Glaciers retreat and expose rock

Pioneer organisms-

the first organisms to colonize a new site

Ex: lichens are the first to colonize lava rocks

Primary Succession-

Rock

Climax community-

a stable, mature community that undergoes little or no succession

Climax community-

Ex: In most of Virginia, the climax community would be a deciduous oak–hickory forest

                                                                                                                                

Primary succession-

Secondary succession-

sequence of community changes that takes place when a community is disrupted by natural disaster or human actions – takes place on existing soil

Secondary succession-

Ex: A fire levels portions of a forest

Secondary succession-

Ex: A farmer plows his field

Secondary succession-

Secondary succession-

Pond Succession

Pond Succession

Land Biomes

Biome- geographic areas that have similar climates and ecosystems

Land BiomesThe 6 most common biomes are:

TundraTaigaTemperate Deciduous ForestTropical Rain ForestGrassland Desert

Land Biomes

Water Biomes

The limiting factors in water biomes are:

Amount of salt (salinity)Amount of dissolved oxygenSunlight

2 Types of Water Biomes

FreshwaterRivers and StreamsLakes and Ponds

SaltwaterOceanEstuariesSeashores (tidal areas)