Term
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Definition
| The variety of life in a given environement |
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Term
| Why is biodiverity important? |
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Definition
| 1) Biodiverisy is known to effect ecosystem processes and services (insurance policy for envi change) 2) Inherant value of living organisms 3) All reasons are not yet understood (The first rule of intellegent tinkering is to save all parts!) |
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Term
| Factors that define diverstiy |
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Definition
| Species richness (# of spp in comm.) and species evenness (relative abundance of each spp.) |
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Term
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Definition
| *Quantifies spp. Richness and evenness *Minimum value of zero *Increases as richness and evenness increase *Can use # of individual of % cover (vegetation) |
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Term
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Definition
| * Quantifies spp. Richness and evenness * values range from 0-1 * Increases as richness and evenness increase *Can use # of individual or % cover (veg) |
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Term
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Definition
| Graph of realative abundance vs. it's rank in abundance (most abundant spp. To least abundant spp.) *Lenth of curve shows richness * Slope indicates evenness. *Greater slope= LESS evenness *Lower slope= GREATER evenness * When spp. Are tied, average ranks to get more accurate representation |
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Term
| General diversity patterns |
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Definition
| FEW highly abundant spp. FEW rare spp. MOST spp. Are moderatly abundant |
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Term
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Definition
| Diversity within habitat *small-scale *sensitive to definiton of habitat |
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Term
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Definition
| Landscape diversity *Total diversity observed in ALL habitats within a geographic area |
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Term
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Definition
| Between-habitat diversity * Spp. Tunover across a environemtnal gradient *The extent to which the various habitats within an area support different spp. *Indicates the degree to which habitats have been partitioned by spp. |
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Term
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Definition
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Term
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Definition
| The total number of Spp. Of all different taxa in the whole world * Don’t know exact number! |
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Term
| Factor that effect diversity |
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Definition
| * Environmental complexity *Disturbance *Productivity * Nutrient/Resource Avaliability *Human impact |
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Term
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Definition
| More complex ecosystems can provide habitat for a greater variety of spp. And/or life history stages *Ex. Foliage height and birds *Plant niches are defined by habitat requirements and limiting factors *Spatial differences in limiting factors = GREATER envi. complexity |
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Term
| Plant diversity increases in proportion with increasing_ |
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Definition
| Spatial variation in limiting factors! *Ex. Nutrient Avaliability, moisture, sunlight, temp, pH, salinity, … |
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Term
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Definition
| Distubance= discrete event that disrupts ecosystems and changes the resources avaliable or the physocal environment Stress= External constraints that limit rates of production (CHRONIC CONDITION) |
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Term
| Intermediate disturbance hypothesis |
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Definition
| Diversity is geatest at intermediate levels of disturbance (Maximun spp. Present) |
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Term
| High disturbance results in_ |
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Definition
| Community dominated by resistant/resiliant or opportunistic, pioneer spp. |
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Term
| Low disturbance results in_ |
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Definition
| Community dominated by the most effective competitors |
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Term
| Intermediate disturbance hypothesis graph |
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Definition
| Plot of Species richness (Y) vs. frequency of disturbance (X) * Should result in a half-circle graph peaking at intermediate disturbance levels. |
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Term
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Definition
| 1)Algae and invertebrates growing on boulders in intertidal zone. Larger boulders require more forcea nd are moved less frequently. Intermediate sized boulders support MORE diversity of spp. 2) Floods and plant spp. Greater diversity of spp. In areas that flood intermediatly. |
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Term
| Intermediate productivity hypotheses |
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Definition
| Maximum diversity occurs at intermediate ecosystem productivity levels! (Low productivity results in dominance by stress tolerant plants, high productivity results in dominance by competitive spp.) |
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Term
| Diversity and Nutrient avaliability |
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Definition
| NEGATIVE realtionship! *Adding nutrients to water of soils DECREASES the diversity of plants and algae! *Increasing nut. Avaliability reduces the number of limiting nutrients, when nutrients are not limiting light becomes the only limiting fatctor. Dominated by spp. most effective at competing for light! * Demonstrated by the DECLINING phase of the unimodal IPH curve!! |
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Term
| Nut. Avali and plant diverity scale influences |
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Definition
| Productivityrelationship only holds at REGIONAL and GLOBAL scales! *There is no consistant relationship at plot scales! |
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Term
| Dynamic Equilibrium Model |
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Definition
| Predits that there will be maximum diversity when there is a balance between productivity and disturbance *LESS productive sites need less disturbance for max. diversity *MORE productive sites need more disturbacne for max. diversity, |
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Term
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Definition
| *Summarize feeding relationships within a community *represent energy flow *represent community structure |
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Term
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Definition
| Primary producers (Plants)>Primary consumers (herbivores)>Secondary consumers (Predators) |
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Term
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Definition
| Shows that biomass and productivity generally decrease with higher trophic levels |
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Term
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Definition
| Diagram that has spp. Grouped into trophic levels *MUCH more complex *Ex. Bear island food web! |
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Term
| Strong Feeding Interactions |
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Definition
| Feeding activities of a few spp. Have dominant influence on community structure *Criteria is degree of influence on community |
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Term
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Definition
| When food chain is disrupted by change in # of a spp., cascades down/up food web. *Bottom up cascade when primary producer is changed * Top down cascade when predator is changed *More likley to occur in ecosystems with lower spp. Diversity and spatiotemporal complexity *Mostly seen in lakes and ponds |
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Term
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Definition
| *Potentially confounding variables have unpredicted effects on traphic cascades (Nut. Status, climate, shading, prey prefrences) *Likley functional AS WELL as numerical factors at work! *Likley that top-down and bottom-up effects both at work in most systems! |
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Term
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Definition
| All trophic links that comprise less than 1% of a consumers diet |
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Term
| Examples of trophic cascades |
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Definition
| *Hathery salmon released>alewife fish decreases>daphina pop increases |
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Term
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Definition
| Certain species that disproportionalty exert an important influence on the ecosystems in which they live |
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Term
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Definition
| *Keytone species! *Predatory starfish that influences spp. Competition and pop. Density of intertidal ecosystem by eating mass barnacles. Prevents copetitive exclusion by dom spp. And creates open space to be colonized by many spp. |
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Term
| More diversty communities tend to have_ |
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Definition
| _a higher proportion of predatory spp! |
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Term
| Sanils and algae diversity |
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Definition
| Intertidal snails feed on green algae. Green algae is competitivly dominant with red algae. When snails are not present, green algae takes over red algae. Snails keep green algae in check and allow red algae to be released by competition. |
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Term
| Competition vs. Diversity |
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Definition
| *Intermediate density of keystone predator species leads to the highest diversity of prey. |
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Term
| Other mechanisms of keystone species |
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Definition
| *Exploitation *Competition *Mutualisms ("mobile link" pollinators, seed dispersal) *Facilitation (positive interactions that maintain ecosystem structure and function.) *Spatial Subsidies (bird guano) *ecosystem engineers (beavers) |
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Term
| Points about keystone species |
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Definition
| *Regulate productivity, structure, or diversity of their communities *Unique in community function *Exceptionally important in their relevance to other species *Have disproportionately large effects on their communities relative to their abundace |
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Term
| Keystone species vs. dominance |
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Definition
| Keystone species are those that exert strong effects on community structure DESPITE relativly low abundance/biomass |
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Term
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Definition
| Oftern have disproportionatly large impacts on community structure and dynamics BECAUSE: *Outside evolutionary experience of local predator/prey/competitor populations *Opportunistic colonizers *Tolerant of WIDE range of conditions |
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Term
| Introduced predators can_ |
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Definition
| *Impose more intense suppression on popoulations of native prey spp. Than native predators preying on coexisting prey. *Bridge aquatic and terrestrial food webs |
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Term
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Definition
| A collection if individuals of the same species |
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Term
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Definition
| An assembladge of populations in an area or habitat |
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Term
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Definition
| A biological community and the physical environment in which it lives |
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Term
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Definition
| The study of how energy, water, and nutrients move through ecosystems |
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Term
| Fundamental areas of ecosystem ecology |
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Definition
| *Primary production *Energy flux *Nutrient cycling |
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Term
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Definition
| Creation of new organic matter |
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Term
| Primary Production and how it is measured |
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Definition
| Fixation of energy by autotrophs Measured By: Rate of CO2 uptake, biomass, or O2 produced |
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Term
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Definition
| The total amount of energy fixed by all autotrophs in an ecosystem |
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Term
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Definition
| The amount of energy left over after autotrophs have met their own energetic needs (The amount of energy avaliable to consumers) |
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Term
| Factors that control primary production in ecosystems |
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Definition
| *Temperature *Moisture *Nutrients *Sunlight |
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Term
| Highest primary production occurs in_ |
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Definition
| Warm, moist environements |
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Term
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Definition
| Actual evapotranspiration -The amount of water that evaporates and transpires off a landscape during the course of a year (mmH20/yr) |
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Term
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Definition
| Tend to be WET and WARM (Tropical Rainforests) |
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Term
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Definition
| Tend to be cold and dry (hot deserts, and cold tundra) |
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Term
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Definition
| AET and net primary production are correlated and have a linear relationship. The greater the AET, the greater the NPP! |
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Term
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Definition
| When temperature is similer, primary production is conrolled by moisture. The great the annual precipitation, the greater the PP |
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Term
| PP vs. nutriant avaliability |
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Definition
| When temp and moisture are silimalr, patterns of soil fertility can cause significant variation in NPP among ecosystems. |
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Term
| Nutrient avaliability controls_ |
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Definition
| Pattern sof primary production in agricultural ecosystems AND in natural ecosystems! |
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Term
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Definition
| addition if limiting nutrients |
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Term
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Definition
| *Dominant primary producers in aquatic ecosystems |
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Term
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Definition
| *Is generally limited by nutrient avaliability due to less: Shading, variable moisture, temp variation. |
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Term
| Algal biomass and NPP have a _ relationship |
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Definition
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Term
| Lakes are often limited by_. Whereas marine evi. Are limited by_ |
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Definition
| Lakes are limited by P, Marine environments are limited by N |
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Term
| What determines the limiting nutrient |
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Definition
| The limiting nutrient will be the one with the LOWEST ration of supply:demand! IN LAKES: N-limitation when N:P <10 P-limitation when N:P >17 |
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Term
| Most observed variation in NPP can be explained by_ |
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Definition
| TERRESTRIAL- Temperature and nutrient avaliability AQUATIC- Nutrient avaliability |
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Term
| Top-down factors that control NPP |
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Definition
| *Herbivory and trophic cascades *Compensitory growth *Grazing effects on nutrient cycling |
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Term
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Definition
| The transfer/transport of matter or energy |
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Term
| In ecosystems energy flux is mediated by_ |
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Definition
| TROPHIC INTERACTIONS! *Feeding (herbivory, predation, detritivory) |
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Term
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Definition
| The transfer of energy from one part of an ecosystem to another |
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Term
| As energy id transferred from one trophic level to another, it is lost due to_ |
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Definition
| *Limited assimilation *Consumer respiration *Heat production |
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Term
| Allochthonous vs. Autochthonous food webs |
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Definition
| Allochthonous food webs incorporate food that was found in a place other than where they or their constituents were formed. Autochthonous food webs only rely of energy from within the ecosystem |
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Term
| Ex. Of allochthonous and Autochthonous energy |
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Definition
| Allochthonous-Leaf litter floating down steam to new area and feeding microorganisms Autochthonous- Periphyton (algae) growing on rocks in stream |
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Term
| Energy losses in ecosystems limit the_ |
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Definition
| Number of trophic levels that an ecosystem can support |
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Term
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Definition
| An element required for the development, maintenance or reproduction of an organism |
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Term
| Elements that comprise 93-97% of living organisms |
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Definition
| Carbon, Nitrogen, Hydrogen, Oxygen, Phosphorous, and Sulfur |
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Term
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Definition
| Nutrients in forms that can be readily absorbed into plant roots and contribute to plant performance and/or growth. |
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Term
| Animals vs. Plant forms of nutrients |
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Definition
| Animals typically use ORGANIC forms while plants typically use INORGANIC forms |
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Term
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Definition
| The use, transformation, movement, and reuse of nutrients in an ecosystem. |
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Term
| Energy flux vs. Nutrient cycling |
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Definition
| Energy flux is typically one-way (UP trophic levels) while Nutrient cyclins constantly recycles nutrients through the ecosystem |
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Term
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Definition
| *N is essential to the structure an functioning of organisms (amino acids, DNA) *78% of earths atmosphere is N, major atmospheric pool that is oconverted by N fixers *ONLY N-fixers can use atmospheric N; other organsisms use other forms *Converting N2 to other forms is a VERY energy-demanding process! |
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Term
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Definition
| Volcanic eruptions, lightning, forest fires, microbial processes, anthropogenic sources (fossil fuels, fertilizers, livestock) |
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Term
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Definition
| Organic N, Minerlization, Volitization, Nitrification, Leaching, Denitrification, N fixation , N immobilization, anthropogenic emmissions, diffusion, assimilation, sorption, diffusion, resuspention. |
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Term
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Definition
| P is necessary to energetics, genetics, and the structure of living organsisms *NOT very abundant in the atmosphere *NO substaintial pool of P *Largest quantities found in mineral deposits and marine sedimanets *limiting nutrient in most lakes. |
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Term
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Definition
| *Slowly released in ecosystems by the weathering of rocks *Released by mineral deposits absorbed by plants and recycled through ecosystem *Washed into rivers/oceans where is remains dissolved and settles into marine sediments *Sediments are eventually formed into new rock, starting the process over again. |
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Term
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Definition
| Organic (P) and Mineral (PO43-) |
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Term
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Definition
| The conversion of nutrients from organic form to inorganic forms |
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Term
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Definition
| The breakdown of organic matter by fungi and bacteria |
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Term
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Definition
| PRIMARY influences- Temperature and moisture SECONDAY influences- soil fertility and chemical composition of litter. |
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Term
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Definition
| Have a POSITIVE linear relationship and are highly correlated |
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Term
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Definition
| The cycling of nutrients as they are carried downstream *LITTLE nutrient cycling occurs in one place! |
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Term
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Definition
| The length of stram required for a nutrient atom to complete one cycle |
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Term
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Definition
| S-spiraling length V-Average dowstream velocity T-Average time to takes to complete a cycle |
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Term
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Definition
| The steam system is MORE efficient |
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Term
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Definition
| Stream insects that break down leaf matter into smaller parts. *VERY important key process in stream nutrient cycling |
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Term
| In aquatic ecosystems 3 factors effects decomp |
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Definition
| 1. Temperature @. [nutrients] in water 3. Chemical composition of the water |
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Term
| Increased shredder diversity leads to_ |
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Definition
| Increased rate of nitrient cycling. WHY? |
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Term
| Large mammel grazing increases_ |
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Definition
| *Primary productivity *Plant biomass turnover * Nutrient cycling |
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Term
| Without grazing Nutrient cycling is_ |
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Definition
| SLOWER. It is influenced only by decomposition |
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Term
| Small animals effect nutrient cycling and productivity by_ |
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Definition
| *digging holes, building mounds, and altering topography *Bringing N-poor soil to the surface creating a mosaic of soil fertility *Alters patterns og plant community composition |
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Term
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Definition
| *Fix atmospheric N and convert it to NH3 which is then converted to NH4 which can then be incorporated into plant activities. *Then transferred through soils for succession |
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Term
| Deforestation vs. Nutrients |
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Definition
| * Loss of evirontranspiration, nutrient uptake, nutrient storage *Greater nutrients in soil water that can then run off, peak flows, erosion, losses |
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Term
| Life cycle of the pacific salmon |
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Definition
| born in stream, travel out to ocean for lifespan, return to stream to spawn and die. Colelcts N15 in marine environment and bring it back to stream. |
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Term
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Definition
| Naturally-occuring stable isotope, 0.37%average terrestrial abundace. More abundant in marine ecosystems |
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Term
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Definition
| The ration of N15:N14. Useful in determining the N enrichment of returning salomn |
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Term
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Definition
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Term
| How is MDN transferred to terrestrial ecosystyns |
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Definition
| *Bears eat salmon with MDN, bear waste and salmon carcases transfer MDN to soils where it is incorporated into trees. |
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Term
| Effect of increased MDN on terrestrial ecosystems |
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Definition
| *Causes increased growth in trees near the stream and spawning sites. NOT in alder, already N rich species * Alters spp. Composition |
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Term
| Salkmon benefits to tree biomass increase form MDN |
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Definition
| *Roots stabalize banks and filter sediments, control erosion and siltation *Tree shading controls temperature |
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Term
| Salmon/Bear MDN study was an example of_ |
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Definition
| *Exploitation * Trophic Dynamics *Complex food webs *Animal influence on nutrient cycling *Mutualism *Keystone spp. |
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Term
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Definition
| A sequence of compositional or structural changes in a community over time |
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Term
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Definition
| Follows the colonization of unvegetated, geologically fresh terrain (After glacier retreat, newly formed volcanic surface, SLOWER than secondary succession) |
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Term
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Definition
| Follows the colonization of previously vegetated area following a disturbance (After fire, flood, windfall, logging, pathogens) *Soil/Seed bank is still intact *FASTER than primary succesion |
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Term
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Definition
| A stage in the sequence of succession |
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Term
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Definition
| A spp. That colonizes newly disturbed sites |
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Term
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Definition
| A reletivly stable, steady-state community at the end point of succession. *Self replacing *Remains stable until disturbed |
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Term
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Definition
| A state of balance in which opposing forces cancel each other out, so that conditions remain more or less stable |
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Term
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Definition
| A series of communities or ecosystems representing a range of ages or times since disturbance (Used in space-for-time substitution) |
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Term
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Definition
| A relativly discrete event that disrupts ecosystem, communtiy, or population structure and changes resource avaliability or physical structure |
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Term
| Disturbance sets_in motion |
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Definition
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Term
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Definition
| Each serial community modifies the environemtn so that it becomes more sutable for the next. *Later colonists replace earlier ones through competitive exclusion *Climaz comm. Reached when modifications no longer favor subsequent comm. |
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Term
| Possible mechanisms of facilitation |
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Definition
| *Soil ammendment *Shading |
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Term
| Individualistic concept of sucession |
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Definition
| Sucession is driven by individual spp. Life histories *Spp. Respond independantly to envi. Change *NO superorganismal associations or inevitable climax community *Spp. Present at any given time are there due to an interply of many factors |
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Term
| Factors that influence the spp. Present at a given site |
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Definition
| *Timing of disturbance *Dispersal *Presence in seed bed *Life history/adaptation *competitive dynamics *env. Conditions *Variability *random processes |
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Term
| Important concepts of individual concept of sucession |
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Definition
| *Disturbance is natural and common *Sucession may follow different trajectories *Trajectories may diverge OR converge *Various climax communities are possible |
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Term
| Implications of individualistic concept of sucession |
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Definition
| *Contributed to the development of non-equilibrium views of ecology *Emphasized the importance of change and disturbance *Was ofter misinterpreted by envoronemtnalists (If nature is not highly organized, why worry about human impact) |
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Term
| What shifted view from facilitative to individualistc view |
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Definition
| 1) Prarie drought 1933-1940 (Prarie grass was considered true climax comm, but was replaces with different spp. After drought 2)American Chestnut blight (Loss of dom spp. Didn’t result in a collapse of eastern northern american forests, other spp. Just increased in abundaces) |
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Term
| 3 proposed models of sucession |
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Definition
| 1)Facilitation 2)Inhibition 3)Tolerance |
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Term
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Definition
| *Only certain spp pioneer after disturbance, earlier spp. Modify envi so it becomes more suitable to later spp. *Later spp. Outcompete and exclude earlier spp. *Climax comm establish when resident spp. No longer facilitates colonization by other spp. |
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Term
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Definition
| *Initial colonization driven by dispersal, timing, and chance *Earlier spp. Modify envi for later spp. *Later spp come in when earlier spp are removed by physical/biological factors that cause mortaility *Climax comm made up of long-living spp. Able to withstand damage by physical/biological factors |
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Term
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Definition
| Initial colonization driven by dispersal, timing, and chance *early spp. DO NOT facilitate OR inhibit later spp. (might alter envi and make it less suitable for themselves ex. Density dependant) *Later spp. Are those tolerant of envi. Conditions during sucession *CLimaz comm. established when all possible tolerant spp. have been recruited |
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Term
| Stand age vs. spp richness |
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Definition
| Spp. Richness tends to increase with stand age NOT ALL GROUPS! |
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Term
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Definition
| *Sessile organisms in intertidal zone *Clear-cutted forest |
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Term
| Sucession and soil properties |
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Definition
| *Soil depth of ALL major soil layers increase with each sere *N, moisture, and organic matter all increase with subsequent sucession *P, pH, and bulk density all DECREASE with sucession |
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Term
| Biomass accumulation model (BAM |
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Definition
| Model for ecosystem recovery following disturbance in 4 PHASES! |
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Term
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Definition
| Following a disturbance! 1) Reorginization phase- ecosystem continues to lose biomass and nutrients 2) Aggradation phase- Biomass increases 3)Transition phase- Biomass will decline 4) Steady-state phase- biomass is now constant |
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Term
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Definition
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Term
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Definition
| The ability of a community or ecosystem to maintain structure/function in the face of a potential disturbance |
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Term
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Definition
| The ability of a comm/ecosystem to return to its ORIGINAL structure/function after a disturbance |
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Term
| Chief mechanism for resilience |
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Definition
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Term
| Major characteristics of disturbance |
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Definition
| *Frequency *Intensity *Duration *Spatial Extent *Seasonality |
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Term
| The rlationship between frequency and intensity |
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Definition
| INVERSLY proportional *In areas of frequent disturbance, organisms tend to be well-adapted to withstanding and recovering from disturbace *In areas with infrequent disturbance, orgs are not well adapter to dealing with them. |
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Term
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Definition
| a departure from average conditions *Sometimes average conditions entail a substantial variation! Org wil adapt to normal conditions even if they have HIGH variation |
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Term
| Changes in disturbance regime |
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Definition
| Can be viewed as a type of disturbance itself! EX. Suppressing fires in area that naturally have forest fires! |
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Term
| River and riparian ecosystems vs. disturbance |
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Definition
| River and riparian ecosystems are dependant on periodic disturbance! *Old trees wil not get replaced *Pop decline resulting from age distribution being dominated by older individuals |
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Term
| Island spp. Richenss is determined by_ |
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Definition
| *Rate of immigration vs. rate of extirpatrion *Distance from mainland *Size of island |
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Term
| Island Biogeography can be applied to_ |
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Definition
| Actual island as well as ecological reserves |
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Term
| # of spp. Present on an island represnets_ |
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Definition
| A dynamic equilibrium between the rate of immigration and the rate of extinction/extirpation *Graph look similar to an X (intersecting J-shaped curves) Number of spp. Is the point of intersection |
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Term
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Definition
| That one large island is better tha several small islands EVEN if the total area is equal. *Spp. Richness is increasing with habitat area! *Debate on the extent to which smaller reserves share spp. |
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Term
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Definition
| Discontinuity in habitat *limits dispersal *Reduces access to mates *Diveds popoulations into isolated subpopulations |
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Term
| Smaller popoulations are at greater risk for_ |
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Definition
| *Inbreeding depression *Genetic Drift |
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Term
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Definition
| The portion of island near its perimeter *Area is influienced by the adjacent environemtn *Microclimate that is different from the interior |
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Term
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Definition
| *Easily dispersed, r-selected spp. *generalists tolerant of open conditions Ex. Mule Deer |
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Term
| Genetic Variation of Island pop. |
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Definition
| *Genetic variation is lower in isolated, smaller, island popoulations |
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Term
| Why are corridors important |
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Definition
| They are important for maintaining genetic variability, viability of island populations |
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Term
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Definition
| *Extinction is a natural process *99% of all spp. That were once alive are now extinct *Current rate of extinction is abnornmally high (on par with 5 catestrophic mass extinctions in earths history.) |
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Term
| The big 5 mass extinction events |
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Definition
| 1) Cretaceous-Tertiary Extinction 2) Triassic-Jurassic Extinction 3)Permian-Triassic Extinction 4) Late Devonian Extinction 5)Ordovian-Silurian Extinction |
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Term
| Todays extinction can be understood by looking back at the _ era |
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Definition
| Pleistocene era! (aka. ICE AGE!) |
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Term
| Potential causes of pleistocene extinction |
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Definition
| *Climate change *Habitat loss *predation *Meterorites |
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Term
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Definition
| Characterized by the manufacture of the "clovis" point and distinctive bone and ivory tools. *Clovis people were specialized hunters of big mammels *End of clovis perios coincides with big mammel extinction |
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Term
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Definition
| Intensive hunting caused megafaunal crash within <1000 years. |
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Term
| Summary points of Pleistocene Extinction |
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Definition
| *Between 50-10 thousand years ago most large land mammels became extint everywhere but africa *Extinction focused on large, slow moving and bredding animals *Evidence that human activities (esp. hunting) helped precipitat extinction *Climate change affected timing, geography, and magnitude |
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Term
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Definition
| *Extinctions continue due to habitat loss and overkill *Debate on the beginning of the period *Currently in the middle of a marine mass-extinction |
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Term
| Three evolutionary ghost stories |
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Definition
| Speed demons - Strange fruit -Chondor Chow |
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Term
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Definition
| Pronghorns in western US can run faster than any predator because the evolved to escape fast predators that are now extinct |
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Term
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Definition
| Trees with tasty fruits that have big pits and are not easily dispersed or eaten are now endangered because they evolved to be dispersed by large mammels that are now extinct |
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Term
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Definition
| Chondors used to feed on the carcasses of large mammels that are now extinct. They are drawnto cattle ranches and populations are on the brink of extinction due to poaching, lead shot, and habitat destruction. |
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Term
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Definition
| Proposed to create a facismal of spp. That have dissapeared |
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Term
| Problems with the re-wilding proposal |
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Definition
| *Ecosystems have changed since late pleistocene *Modern day decendants are not the same *Re-wild fauna not adapted to life on the plains *Unforseen ecosystem effects *Possibel eating of people *Expensive? |
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Term
| Siberias pleistocene park |
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Definition
| *Reintorduction of large herbivores *Plans to reintroduce large prpedators *Cloned mammoth? |
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