Chapter 59 & 60 Flashcards
The species in an ecosystem are divided into ___ ___. They are different feeding levels.
trophic levels
The species that are at the base trophic level, the level that supports all others, are called ___ ___.
primary producers
Primary producers are usually ___ organisms such as plants or phytoplankton. Primary producers can also be ___.
photosynthetic
chemosynthetic
The next trophic level above that of primary producer consists of heterotrophs such as herbivorous animals, these organisms are called ___ ___
primary consumers
The next trophic level above primary consumer contains carnivores and these organisms are called ___ ___
secondary consumers
There can be ___ and ___ consumers as well.
tertiary
quaternary
The various trophic levels starting with primary producers form a ___ ___
food chain
Most ecosystems are quite complex and are called ___ ___
food webs
the total amount of light energy converted into chemical energy in a certain time period
Primary productivity
total primary productivity
Gross primary productivity
equal to the gross primary productivity minus the energy used by the producer for respiration
-50%-90% of gross primary productivity
Net primary productivity
Primary productivity is often expressed as ___ (weight) of vegetation (or other producers) added to the ecosystem per unit area per unit time.
-Typically g/m2/year
biomass
___ ___ is the rate consumers convert the chemical energy in their food into their own new biomass. Much energy is lost during the incorporation of the energy from food into a consumer’s biomass.
Secondary productivity
___ ___ is the percentage of energy transferred from one trophic level to another. This is usually highly variable.
Ecological efficiency
shows the loss of energy in a food chain
Pyramid of productivity
abundance of species at each trophic level
Pyramid of numbers
___ are cycled through an ecosystem. There are water cycles, carbon cycles, nitrogen cycles, phosphorus cycles, and other cycles.
Chemicals
biochemical cycles
___ lakes are filled with algae or aquatic plants. The abundance of algae or plants is often caused by fertilizer or sewage runoff. ___ and ___ are key nutrients contributing to these conditions.
Eutrophic
phosphorous
nitrogen
___ ___ study and are involved in preserving ___.
Conservation biologists
biodiversity
___ is the diversity of species found in an ecosystem.
Biodiversity
We are now in the midst of a ___ ___, a mass extinction event of our own doing. Threats to biodiversity include ___ destruction, ___, and competition from ___ ___.
biodiversity crisis
habitat
over-exploitation
exotic species
areas that contain unique species
Biodiversity hot spots
the smallest number of individuals needed to maintain a population
Minimum viable population size
the amount of habitat needed to maintain a population
Minimum dynamic area
if removed entire ecosystem collapses
keystone species
provide status of overall health of an ecosystem
indicator species
large habitat, if habitat is protected many other species will be protected
umbrella species
instantly recognizable species – symbols of conservation campaigns
flagship species
