Unit 1 - The Living World: Ecosystems

Individual

One organism

Population

Group of individuals of same species

Community

All living organisms in an area

Ecosystems

All living and non living things in an area (plants, animals, rocks, soil, water, air)

Biome

The plants and animals found in a given region (determined by climate)

Mutualism

Relationship that benefits both organisms

Commensalism

Relationship that benefits one organism and doesn’t impact the other

Competition

Organisms fighting over a resource like food or shelter; limits population size

Predation

One organism using another for energy source (hunters, parasites, even herbivores)

Herbivores

Plant eaters; eats plants for energy

True predators

Carnivores; kill and eat prey for energy

Parasites

Uses a host organism for energy, often without killing the host & often living inside host (venom)

Parasitoids

Lays eggs inside a host organism; eggs hatch and larvae eat host for energy (ex. Parasitic wasps, bot fly)

Symbiosis

Any close and long term interaction between two organism of different species (mutualism, commensalism, and parasitism)

Competition

Reduces population size since there are fewer resources available and fewer organisms can survive (food, water, shelter, space, mates, light, etc.)

Interspecific

Competition between two different species

Intraspecific

Competition between members of the same species

Resource partitioning

Different species using the same resource in different ways to reduce competition

How do animals reduce competition?

By using resource partitioning, temporal partitioning, spatial partitioning, and morphological partitioning

Spatial partitioning

Using different areas of a shared habitat (different length roots)

Morphological partitioning

Using different resources based on different evolved body features

Primary Productivity (PP)

Rate that solar energy is converted into organic compounds via photosynthesis over a unit of ime

What are ecosystems with high PP usually?

More diverse than ecosystems with low PP

Gross primary productivity (GPP)

Total amount of sun energy (light) that plants capture and convert to energy (glucose) through photosynthesis

Respiration loss (R)

Plants use up some of the energy they generate via photosynthesis by doing cell respiration

Net primary productivity (NPP)

Amount of energy (biomass) leftover for consumers after plants have used some for respiration

Equation for net primary productivity

NPP = GPP - R

Ecological Efficiency

Portion of incoming solar energy that is captured by plants and converted into biomass - only 1% of incoming sunlight is captured and converted into GPP via photosynthesis

Trends in productivity

The more productive a biome, the wider the diversity of animal life it can support

Factors that lead to high NPP

Water availability, higher temperature, and nutrient availability

What defines a biome?

Annual temperature and precipitation average

Latitude

(Distance from equator) determines temperature and precipitation which is why biomes exist in predictable pattern on earth

Tundra

Temp Range (C): -10 to 5

Precipitation Range (cm): 0 to 100

Major Plant Types: shrubs, lichens, no trees

Example Animal Species: Hare, arctic fox, polar bear, caribou

Facts: permafrost (subsoil is permanently frozen) - no deep rooted plants, low precipitation, cool temperatures, shallow soil = low NPP

Taiga (Boreal Forest)

Temp range (C): -5 to 10

Precipitation Range (cm): 25 to 200

Major Plant types: Conifers (pine, spruce)

Example Animal Species: Moose, wolf, bear, beaver

Example location: North American, Europe, Russia

Facts: short growing season, low precipitation + slow decomp (from cool temperatures) + shallow soil = low NPP

Temperate Rainforest

Temp range (C): 5 to 20

PRECIP range (cm): 150 to 350

Major plant types: Coneifers (pine, spruce)

Example animal species: bear, grouse, banana slug, spotted owl

Example Location: pacific north west, west coast of Canada

Facts: coastal biome, high precip + moderate temp = high NPP, big trees, lot of plants, rapid plant growth = low soil nutrient levels

Temperate seasonal (deciduous) forest

Temp range (C): 5 to 20

Precip range (cm): 50 to 225

Major plant types: broad leaf deciduous trees (oak, maple, hickory)

Example animal species: squirrel, chipmunk, bobcat, white-tailed deer

Example location: New England

Facts: warmer temps = rapid decomp = high soil nutrient levels, high NPP, prime target for agricultural development

Scrubland (Woodland/ Chaparral

Temp range (C): 5 to 20

Precip Range (cm): 25 to 125

Major Plant types: drought resistant shrubs (sages, yucca, etc.)

Example Animal Species: mule deer, roadrunner, coyote, jack rabbit

Example Location: Mediterranean coast, Southern California

Facts: NPP limited by summer high temperatures and low precipitation, species evolved around regular wildfirecycles

Temperate grassland

temp range (C): -5 to 20

Precip range (cm): 0 to 50

Major plant types: grasses

Example animal species: bison, pronghorn, prairie dog, black-footed ferret, sage grouse

Example location: Oklahoma, Kansas

Facts: NPP limited by temp and precip, species evolved around regular wildfire cycles (why there’s so few trees)

Tropical Rainforest

Temp range (C): 20 to 30

Precip range (cm): 250 to 450

Major Plant Types: Broad-leaf evergreens

Example animal species: poison dart frog, gorilla, orangutan, chimpanzee, jaguar

Example location: Amazon, Congo basin, Sumatra

Facts: very rapid plant growth = very low soil nutrient levels, most biodiversity (2/3 terrestrial species), very high NPP

Savanna

Temp range: 20 to 30

Precip Rangel 50 to 275

major plant types: broad leaf grasses

Example animal species: zebra, lion, elephant, rhino

Example location: Serengeti

Facts: distinct wet and dry season, high decomp rate = fertile soil = agriculture, NPP limited by precip, grazing and regular wildfire keeps large, woody plants at bay

Desert

Temp range: 18 to 31

Precip range: 0 to 100

Major Plant types: Cacti and succulents

Example Animal Species: Camel, Kangaroo Rate, Gila Monster, Scorpion, Jackal

Characteristics of Aquatic Biomes

Salinity, Flow, Depth, Temperature

Salinity

How much salt there is in a body of water, determines which species can survive and usability for drinking

Flow

Determines which plants and organisms can survive, how much O2 can dissolve into water

Depth

Influences how much sunlight can penetrate and reach plants below the surface for photosynthesis

temperature

Warmer water holds less dissolved O2 so it can support fewer aquatic organisms