Forest Ecology Final Exam
Describe the four stages of forest stand development, what occurs in each stage
1. Stand Initiation: from new seeds, preexisting roots stock sprouts 2. Stem Exclusion: growing space occupied, competition occurs 3. Understory Reinitiation: overstory gaps created by disturbances, regeneration is recruited 4. Old Growth: late successional condition/complex
Dr. Kidd tallied two oak stems in a 1/2000th acre plot, how many stems per acre is this
4,000 stems per acre
Describe the n-dimensional hypervolume concept and how it relates to a species' niche
n-dimensional set of resources and environments that a species requires to persist. It relates to a species' niche in that it defines their fundamental niche and realized niche
What is the difference between a symbiotic and non-symbiotic mutualism
symbiotic is connected while non-symbiotic is not connected
What are the two main components of diversity, list two indices discussed in lab and your readings
area and number of species (?)
Define mean fire interval (or Fire Return Interval), how can this information be obtained for past decades
book?
List six examples of disturbances
book?
What is the general relationship between disturbance frequency and severity and between severity and recovery time
book?
Define realized niche
The niche that a species actually inhabits, taking into account interspecific competition
Define ecological disturbance
"Any relatively discrete event in time that disrupts ecosystem, community, or population structure, and and causes changes in resources, substrate availability, or physical environment"
List the four general fire survival strategies, describe one example of each
1. Avoid fire damage - bark, bud protection 2. Recover following fire damage - sprouting response 3. Colonize sites after fire - pioneer/early successional seeding characteristics 4. Promote or facilitate fire - flammable foliage and bark
What is the difference between a biome and a plant community
A biome is a group of communities while a plant community is a group of organisms living in the same place or having particular characteristics in common
Define allelopathy and provide two examples of species that utilize allelopathy
A direct or indirect chemical effect of one plant on the germination, growth, or development of neighboring plants; Black Walnut and Juglone, Sorghum and Sorgolene
Define community
A group of organisms living in the same place or having particular characteristics in common
Describe succession
A progressive alteration in the structure and species composition of the vegetation or the directional change with time of the species composition and vegetation physiognomy of a single site
What is a seral stage (sere)
An identifiable stage of succession; usually identified based on the dominant vegetation present
Describe how chronosequence can be used to study succession
As age of chronosequence increases, changes in stand structure, including distribution of trees, percent ground cover, and species abundance, are observed and forest succession can therefore be determined
Describe potential impacts of downstream sedimentation
Declined abundance, diversity, and productivity. Roads have the highest probability of producing sediment and erosion into soils and streams and can alter hillslope hydrology by "creating compact and less permeable surfaces, decreasing infiltration, and increasing drainage networks with road surfaces and ditches," thus causing more erosion and sedimentation
Define an ephemeral stream
Ephemeral streams have flow less than 30% of the year and may not have a well-defined channel
Explain Clements' Organismal Theory and how it relates to succession, particularly climax communities
Early concepts - "organism-like" properties; arises, grows, matures, reproduces, and dies as a unit. Uniform and rigid based on climatic region. It was later (FINISH)
List one example of both an early- and late-successional species
Early: Red Maple Late: Hemlock
List five ways an early-successional species differs from a late-successional species
Early: small seed size, dispersal via wind and animals, seed viability is long and latent in soil, growth rate is rapid, and shade tolerance is low Late: large seed size, dispersal via gravity and eaten by animals, seed viability is short, growth rate is slow, and shade tolerance is high
List six components/variables used to describe a fire regime. What information does each component provide
Extent (how bad), severity (effects), intensity (how fierce), type, frequency (how often), and timing (when)
What is the intent of forestry best management practices
Forestry Best Management Practices (BMPs) are specifically developed to address erosion associated with roads, skid trails, and stream crossings
Who coined the term "forest succession"
Henry David Throeau
Draw a graph illustrating the general trend of a species-area curve: area (x-axis) vs. number of species (y-axis); which type of function (linear, power, logistic) best fits this general trend
Power
What is a disturbance regime
If a disturbance occurs repeatedly and we gain an idea of outcomes (under certain conditions)
Describe Henry Gleason's contributions to today's understanding of community ecology
Individualistic concept - book?
Who introduced the term "succession" and in what year
John Adlum in 1806
What is the term for a tree deformed by wind, typically located along the tree line
Krummholz (book?)
List and describe five types of interactions that can occur among organisms
Mutualism, both organisms benefit Commensalism, one benefits, one neutral Parasitism/Predation, one benefits, one harmed Amensalism, one negatively affects others Neutralism, both neutral Competition, both are harmed but one will win
Do severity and intensity depict the same information, why or why not
No; severity looks at the severity of the damage and looks at what is left of the soil and vegetation while intensity is about how fierce the disturbance was overall
List the six general stages in the Clementsian succession order
Nundation, Migration, Ecesis, Competition, Reaction, and Stabilization
Describe the four ways that mutualisms are important to the life-cycle of woody plants
Nutritional - breakdown/cycling Protection - from enemies and extreme conditions Transport - dispersal (pollen, seeds, spores) Supply of energy - transfers (plants, animals)
How does primary succession differ from secondary succession
Primary succession occurs on previously unvegetated terrain or following catastrophic disturbances where all organic matter was removed or buried and is a very long term process. Secondary succession occurs in an area previously inhabited by vegetation and there are residual effects of organisms and organic matter from organisms present before the disturbance, has biological legacies
What is the difference between point source and non-point source pollution, which type of pollution are BMPs designed to address
Point source pollution (PSP) refers to chemicals and pollutants that are identified from a single source of pollution, such as a pipe or a ditch. Nonpoint source pollution (NPSP), however, is when pollutants are released in a wide area with no single identifiable source. BMPs are designed to address NPSP
Describe the major differences between relay and initial floristics composition models
Relay: one group of plant species modifies the physical environment such that it is favorable to a new group to colonize the area, pattern is "relay-like" Initial: all species are present in the beginning and will dominate at one point in time
What is a serotinous cone, provide two examples of species that have serotinous cones
Require heat to open and release seeds; Jack Pine, Lodgepole Pine
What scientist first used a gradient analysis to describe communities types based on differences in environmental variables and where was this research conducted
Robert Whittaker, 1953, Great Smoky Mountains
List three types of biological legacies. In which type of succession to biological legacies play an important role
Secondary succession; stumps, soil, seed bank
List the three types of niche components and describe one example of each
Spatial: location, where - silver maple in floodplains Temporal: over time, when - Virginia Pine, scrubby pioneer species vs eastern hemlock Functional: physiological adaptations, how - nitrogen fixers, black locust
Why are stream crossings a concern
Stream crossings are an important tool for allowing equipment to cross streams, drains, and drainage ditches, thereby reducing sedimentation and other negative impacts on these waterways. Examples of stream crossings include bridges, rock fords, and culverts
Define tolerance
The capacity of an organism to subsist under a given set of environmental conditions
Define niche
The ecological role of an organism
Define climax community, provide one example of a climax community type
The end point of succession, it is stable and resists major change; mature oak and hickory forest
What is the -3/2 law
The rate at which density-dependent mortality occurs
Define synecology
The study of the relations between groups of organisms or co-existing biological plant communities
What is meant by a "pioneer" species, provide four characteristics that prove advantageous to the function of a pioneer species
They can occupy open areas and often harsh conditions; they are often the first to come in or occupy a site following a disturbance. Light seeded, rapid germination, roots can penetrate deeply into the soil, and rapid growth with little to no competition
Define phsyiological amplitude. How does this range differ from a species' phsyiological optimum range
Tolerance range of the species and includes competing species, but the physiological optimum range refers to conditions for optimal growth and where competing species are excluded