Midterm Review Flashcards
What is a novel ecosystem?
development of ecosystem that differ in composition and/or function have been completely transformed from the historic system: system may be composed almost entirely o species not formerly native or exhibit different functional properties.
What is a Hybrid system?
A system that returns characteristics of the historic system but whose composition or function lies outside the historic range of variability (HRV)
What are examples of abiotic changes?
Climate, land usem pollution, urbanization and nutrient loads
What are 3 types of ecosystem services?
Provisioning services: resources we depend on (food, fuel, etc)
Regulatory services: benefits that occur to us from ecosystem processes (water pollution, natural hazard reduction, pollination)
Cultural services: recreational, aesthetic, and spiritual use of ecosystem
What is ecological restoration?
refers to scientific exploration of ecosystems under repair, including design and implementation, practice of restoring degraded ecological systems
What is an ecosystem service?
Conditions and processes through which natural ecosystem and species tha make them up sustain human life
What is restoration?
The process of assisting the recovery of an ecosystem that has been degraded, damaged, or destroyed, aim to achieve semblance of predisturbance state
What is reclamation/rehabilitation?
The return of a damaged ecosystem to a productive and socially acceptable condition short of restoration
What is creation?
The construction of an ecosystem on a site that has a different type of ecosystem before destruction or damaged occurred
What is abandonment/passive restoration?
the process of allowing a damaged ecosystem to recover from disturbance without human intervention
What is mitigation?
The attempted alleviation of any or all detrimental effects arising from a given action
What is reforestation/afforestation?
The planting of trees, often for timber production, not necessarily native species
List some limitations/constraints of restoring an ecosystem.
- Limited time scale
- lack of understanding of ecology and ecosystem functioning
- presence of exotic species
- cultural values
- climate change and changing endpoints
- residual disturbance
What is succession?
A regular progression of communties replacing each other on a site until a relatively permanent climax community is established
-ecological succession refers to how communities change through time
What is an r-selected species?
early successional, adapted to disturbance, good dispersal capabilities, large numbers of offspring, generalist, shorter lifespan
What is a k-selected species?
later successional, better competitors, smaller numbers of offspring with higher survival rates, specialists, longer lifespan
What is Facilitation?
When early successional species alter the environment to make it more favorable for the establishment of later successional species - common in highly disturbed ecosystems
What is inhibition?
When early successional species alter the environment to make it less favorable for the establishment of later successional species
What is assisted migration or managed translocation?
intentionally moving individuals of a species outside their present range in response to changing climatic conditions
What is the difference between primary and secondary succession?
Primary succession - community change in a location that has never supported biotic community
Secondary succession - community change in a location where an existing biological community has been disrupted by disturbance
What is a disturbance cycle?
events such as fires, floods, and windstorms, to the extent that they severely damage or destroy an existing community, are considered to be the inhibitors of successional change
What is system resilience?
a community is considered to be resilient if it return to normal after a disturbance
What is a keystone species?
One way a single species may maintain community stability is by acting as a keystone predator, remove the keystone, and the arch (or community) becomes unstable or changes to a different state
What is a metapopulation?
where multiple populations of an organism occur across a landscape, providing redundancy that may enable the species to survive despite the occasional extirpation of a local population
A set of geographically isolated subpopulation that are interconnected by gene flow and colonization, often consist of one or more core populations that are persistent and a number of satellite populations
What is sedimentation?
when the flowing water slows enough that it can no longer support its load of suspended material, the soil comes to rest
What is the critical zone?
The critical zone is the collective term used to describe the portion of the biosphere at the interface of the lithosphere (earth), atmosphere (air), and hydrosphere (water)
What is stratification?
Exposing seeds to a period of cold temperature moisture to deactivate growing inhibiting hormones
What are 4 approaches to faunal restoration?
- remove existing stress - ex. exotic animals, toxic chemicals, reduce hunting
- restoring habitat for certain faunal guilds - ex. trees to encourage birds paving rocks - shelter for reptiles
- restoring habitat for specific species - nest hole protectors, and mimicking colony sounds from murres
- captive breeding and reintorduction vs translocation - hard vs soft
What is endemic?
Species that are found nowhere else
What are some problems with small populations?
- low genetic variability - weak and infertile offspring
- high demographic stochasticity - br & dr vary naturally
- susceptible to environmental stochasticity - small populations more likely to be extricated from disturbance than large populations
- low population cannot find mates
What are some characteristics of tropical forests?
- high level of diversity
- seasonality determined by rainfall rather than temperature
- highly weathered soils
- poorly understood
- aren’t as stable
What is scarification?
Breaking down seed coat by mechanical nicking or soaking seeds in acid or hot water
What is cation exchange capacity?
quantity of cations that can be absorbed by soils is a function of soil texture and chemistry
Why do invasive species spread so rapidly?
A. well adapted to disturbances: good dispersal abilities, resilience, rapid growth, often vegetatively reproduced
B. lack of natural predator
C. create favorable conditions
What are 7 methods to reestablishing vegetation?
- seeds
- topsoil
- nursery grown seedlings
- transplanted seedlings/wildlings
- cuttings, roots, bulbs
- mowing/clipping
- sods/turves
What are strategies for restoring to adjust to climate change?
- Choose genotype that will be adapted to new conditions/extreme
- diverse set of genotypes and let new conditions select for best adapted
What are 7 factors influencing success of reintroductions?
- population size reintroduction
- source population wild
- removing the cause of decline
- soft release vs hard release
- herbivores
- long term commitment
- release into core area
Why are invasive species a problem?
- reduces survival of native species: predation, disease, competition, allelopathy
- influence resource supply thereby influencing the community composition
- alter disturbance frequencies
- crossbreed with natives
- reduce agriculture production
May lose seeds to:
Low germination, seed predation, seedling survival
What are some obstacles to restoring in developing countries?
Lack of funding, population growth, lack of enforced regulation
What are hazardous waste treatments?
- Bioremediation/phytoremediation - use of microorganisms/fungi to detoxify hazardous chemicals
- Chemical transformation
- removal: physical removal, thermo (convert into ash), chemical extraction
- phytoextraction
What are methods for removal of exotic species?
Soil sterilization, biological control, physical removal, herbicides:potential negative effects, may develop resistance
How are invasive species spread?
European colonization, horticulture and agriculture, accidentally, pest control, and erosion control
Clement’s view of succession and critiques?
- Specific sequence of plant comm. occur on given site
- each community prepares the site for sequent invaders
- at end - stable climax
Dunwiddie
Boeing - species redundancy ( a good idea)
Microsoft - functional redundancy
Starbucks - connectivity (relate to corridor)
