Term
| what percentage of dry biomass is produced on land? |
|
Definition
|
|
Term
| what percentage of biomass production is used by humans? |
|
Definition
|
|
Term
| is concerned with the cycling of matter and the associated energy through an ecosystem |
|
Definition
|
|
Term
| who depicted ecosystems as a series of simple energy flow diagrams |
|
Definition
|
|
Term
|
Definition
| the rate of primary production |
|
|
Term
|
Definition
| the total energy assimilated by photosynthesis |
|
|
Term
|
Definition
| considers energy lost by respiration and is the energy accumulated in plant biomass and thus available to consumers |
|
|
Term
| Net production of plants and algae can be measured |
|
Definition
| -by CO2 assimilation in light and CO2 production in dark -Using radioactive isotope of C-14 -By O2 uptake in dark and O2 uptake in light |
|
|
Term
|
Definition
| the level of light intensity at which assimilation of energy by photosynthesis just balances loss of energy by respiration |
|
|
Term
|
Definition
| the level of light intensity above which the rate of photosynthesis no longer responds to increasing light intensity |
|
|
Term
| The optimum temperature for photosynthesis |
|
Definition
| about 16 C in many temperate species and high as 38 C in tropical species |
|
|
Term
| Photosynthetic efficiency |
|
Definition
| the percentage of the energy in sunlight that is converted to net primary production during the growing season |
|
|
Term
|
Definition
| the number of grams of dry matter produced (net production) per kg of water transpired |
|
|
Term
|
Definition
| the ratio of dry matter production in plants to the assimilation of a particular element |
|
|
Term
| Nutrients that limit primary production |
|
Definition
|
|
Term
|
Definition
the percentage of energy transferred from one trophic level to the next
This value is generally 10% |
|
|
Term
|
Definition
| the ratio of assimilated energy to ingested energy |
|
|
Term
| Net production efficiency |
|
Definition
| the energy channeled into growth and reproduction as a percentage of the total assimilated energy |
|
|
Term
|
Definition
| dead remains of plants and indigestible excreta of herbivors |
|
|
Term
| Net primary production consumed by herbivores |
|
Definition
1.5% - 2.5% in temperate decidious forests
12% in old-field habitats
60% - 90% in plankton communities |
|
|
Term
|
Definition
the rate of energy transfer between trophic levels
The longer the residence time, the greater the accumulation of energy |
|
|
Term
| Biomass accumulation ratio |
|
Definition
| the ratio of biomass to productivity |
|
|
Term
|
Definition
| the balance of C gain and C loss in an ecosystem |
|
|
Term
|
Definition
| transformations that incorporate inorganic forms of elements into the molecules of organism |
|
|
Term
|
Definition
| transformation of organic carbon back to an inorganic form, accompanied by the release of energy |
|
|
Term
|
Definition
| a representation of an ecosystem in which the various components are portrayed as units (compartments) that receive inputs from and provide outputs to other such units |
|
|
Term
| Three classes of processes cause carbon to cycle through ecosystems |
|
Definition
-Assimilatory and dissimilatory reactions, primarily in photosynthesis and respiration
-Exchanges of carbon dioxide between the atmosphere and the oceans
-Precipitation of carbonate sediments in the oceans |
|
|
Term
reduction rxns
oxidation rxns |
|
Definition
energy requiring
energy releasing |
|
|
Term
|
Definition
|
|
Term
|
Definition
| ammonia -> nitrite -> nitrate |
|
|
Term
|
Definition
| nitrate -> nitric oxide (NO) -> molecular nitrogen |
|
|
Term
| The breakdown of leaf litter in a forest occurs in four ways |
|
Definition
-By water leaching out soluble minerals and small organic compounds
-By consumption by large detritivores
-By breakdown of the woody components and other carbohydrates in leaves by fungi
-By decomposition of almost everything by bacteria |
|
|
Term
| Saprotrophic (“detritus eating”) fungi |
|
Definition
| play a unique role in regenerating nutrients by breaking down some types of litter that are resistant to decomposition by other organisms |
|
|
Term
| Two principal forms of mycorrhizae are recognized |
|
Definition
Arbuscular mycorrhizae fungi (AMF)
Ectomychorrhizae (EcM) |
|
|
Term
| Clements’s holistic concept |
|
Definition
| each species contributes to the dynamics of the whole system – analogous to superorganism |
|
|
Term
| Gleason’s individualistic concept |
|
Definition
| community is not a discrete unit. Species that are adapted to certain environmental conditions exist together |
|
|
Term
|
Definition
| distributions of several species coincide closely, but are largely separated form those of other sets of species |
|
|
Term
|
Definition
| a zone of transition between communities |
|
|
Term
|
Definition
| distribution of each species may not coincide closely with the distribution of others, so that the species appear to be independently distributed along a spatial gradient of ecological conditions |
|
|
Term
|
Definition
| the distribution of species along an environmental gradient |
|
|
Term
|
Definition
| abundance of each species is plotted on a continuous gradient of one of more physical conditions (temp. light level etc.) |
|
|
Term
| Plant distributions are shaped by |
|
Definition
-the adaptations of the species to env. conditions and
-the interactions among species that compete with one another along env. gradient |
|
|
Term
|
Definition
| species whose types of resources consumed within trophic levels and the methods or locations of foraging are similar |
|
|
Term
|
Definition
| consumers that maintain diversity among resource species and thereby influence the structure of a community |
|
|
Term
|
Definition
| emphasize feeding relationships among species (complex) |
|
|
Term
|
Definition
connections between species are quantified by the flux of energy between a source and its consumer
(less complex) |
|
|
Term
|
Definition
| show the influence of a species on the growth rates of other species’ populations (least complex) |
|
|
Term
|
Definition
| a measure of the ability of a system to resist change in the face of outside influence |
|
|
Term
|
Definition
| the ability of a system to return to some reference state after disturbance |
|
|
Term
| Switching communities between states requires |
|
Definition
| dramatic external perturbation or a loss of a keystone consumer |
|
|
Term
|
Definition
| when the indirect effects of consumer-resource interactions extend through additional trophic levels of a community |
|
|
Term
|
Definition
| when higher trophic levels determine the sizes of the trophic levels below them |
|
|
Term
|
Definition
| when the size of a trophic level is determined by the rate of production of its food resource |
|
|
Term
|
Definition
|
|
Term
|
Definition
| involves gradual infilling of ponds with organic matter |
|
|
Term
|
Definition
| the scale of an environmental gradient based on changes in physical characteristics or community composition along that gradient |
|
|
Term
|
Definition
| processes by which one species increases the probability of a second species becoming established |
|
|
Term
|
Definition
| presence of one species prevents another species to establish |
|
|
Term
|
Definition
| species persist (in low dominance) for a long time in a community |
|
|
Term
|
Definition
| develops in an ephemeral habitat |
|
|
Term
|
Definition
| a self perpetuating, repeating sequence of stages produced by ongoing succession, non of which by itself is stable, but which together constitute a persistent pattern |
|
|
Term
| avg residence time of carbon |
|
Definition
|
|
