Chapter 5: Ecosystems, Energy, Patterns, and Disturbance Flashcards
Biomes
ecosystems with similar vegetation and climate
Describes where energy and nutrients go as they move from one organism to another
Food chain
Interconnection of food chains to form complex feeding relationships
Food web
Trophic Levels
show movement of energy and materials
Autotrophs
produce organic material from inorganic matter by using an external energy source
Heterotrophs
must consume organic material to obtain energy
Autotrophs are also referred to as…
producers
Consumers
eat living prey
Decomposers
scavengers, detritus feeders, and chemical decomposers that eat dead organic material
Chemosynthesis
some bacteria use energy in inorganic compounds to form organic compounds
Examples of consumers
animals, fungi, most bacteria, most protists
Primary consumers (herbivores)
eat producers
Secondary consumers
feed on primary consumers
How are consumers categorized?
according to their food source
Carnivores
secondary or higher-order meat eaters
Omnivores
feed on both plants and animals
Detritus
dead plant material, fecal wastes, and dead bodies
Detritus is organic and high in potential energy for:
- Scavengers
- Detritus feeders
- Chemical decomposers
Scavengers
decomposers that break down larger pieces of matter (vultures)
Detritus feeders
decomposers that eat partly decomposed matter (earthworms)
Chemical decomposers
decomposers that bread down molecule sized matter (fungi and bacteria)
Climate
a description of the average temperature and precipitation of a region
Biomes at higher altitudes are similar to…
biomes at higher latitudes
The more rainfall and warmer temeratures…
the closer you are to the equator
What determines where a species can live?
Individual ranges of tolerance to temperature and precipitation
Temperate deciduous forest
72-200 cm (30/80 in.)/yr
Grassland (prairie) biome
rainfall is less than seasonal
Desert biome
less than 25 cm (10 in.)/yr
Have broad-leaved evergreens that cannot tolerate freezing
Tropical rain forsts
Trees drop their leaves and become dormant during freezing temperatures
Deciduous forest
Tolerate the harsh winters and short summers of northern regions
Coniferous forests
Permafrost
permanently frozen subsoil
Altitude
distance from sea level
Dry, hot days, cold nights, thin, porous soils, scattered shrubs, cacti, rodents, lizards, raptors
Desert
Frequent fires, rich, deep soils, center of continents, grass species dominant, large grazing mammals, insects, rodents, hawks
Grasslands and Prairies
Heavy rainfall year round, soils thin and poor in nutrients, 26 degrees celcius, broad-leaf evergreens, dense canopy, vines
Tropical rainforest
Temps below freezing in winter, summers warm and humid, well-developed soils, broad-leafed deciduous trees, some conifers, shrubby undergrowth, ferns, mosses, many mammals, birds and amphibians
Temperate forest
Long, cold winters, precip. light in winter, heavier in summer, acidic soils, conifers, large herbivores, mice, hares, lynx, bird nesting area
Coniferous forest
Bitter cold, short growing season, small plant life, low precipitation, thin soils, permafrost, shrubs, lichens, mosses, grasses, hares, artic foxes, caribou, migrant shorebirds.
Tundra
What determines aquatic and wetland ecosystems?
depth, salinity, and permanence of water
Bodies of standing water, seasonal stratification of watter. Occur where there are physical depressions in landscape
Lakes and ponds
Flowing water, high DO’s, often turbid from runoff, lots of insect larvae, occur where precip. and groundwater flow by gravity towars oceans
Streams and Rivers
Standing water, at times dry, thick organic sediments, high nutrients, follow lakes and ponds in succession
Inland wetlands
Variable salinity, 2-way currents, rich in nutrients, turbid, where rivers meet oceans
Estuaries
From coastline continental shelf, high in nutrients
Costal ocean
Great depths, all byt upper 200m, dark and cold, poor in nutrients, covers 70% of earth, low productivity
Open ocean
Open oceans accounts for lots of productivity but they have a low…
rate of productivity
Primary production in open oceans is limited by…
scarce nutrients
Disturbance
a significant change that kills or displaces many community members
Ecological succession
transition from one biotic community to another
Pioneer species
colonize a newly opened area first
Lichens
pioneer species best suited for colonizing bare rock
Primary succession
the process of initial invasion and progression form one community to another
Where does primary succession occur?
in areas lacking soil and plants
Secondary succession
occurs in an area cleared by a disturbance
How does secondary succession start?
With pre-existing soil
What can send succession back to an earlier stage?
Disturbances
For succession to occur, what must already be present in the area?
plants and animals
Resilience
an ecosystem’s ability to go back to normal after a disturbance
Resilience mechanism includes the processes of:
- Replenishment of nutrients,
- Dispersion by plants and animals
- Regrowth of plants and succession
Resilience helps maintain the stability of…
ecosystems
Tipping point
a situation or disturbance that can move an ecosystem in one direction or another
What tends to lower ecosystem services?
Human actions
Ecosystem capital
when we depend on natural systems for goods and services
What percent of the land’s primary production is used to support human needs?
40%
How many major ecosystem goods and services provide $41 trillion to uman welfare each year?
17
Incremental value of services
places an economic value on the relationship between changes in the quanity/quality of services and human welfare
Vital ecosystem services should be included in calculating…
Costs and benefits of a proposed change in land use
Ecosystem capital stock
ecosystems and their polulations
How can you restore an area?
by stopping the abuse
Ecosystems can be restored if:
- abiotic factors are unchanged
- population of species still exist
- alien species aren’t introduced
Stakeholders
all people with a stake in an ecosystem’s health
The Millennium Ecosystem Assessment’s report concluded that…
ecosystems may no longer be able to sustain future generations
