EX 2 TECH: Vegitation and measurement

What does vegetation refer to in wildlife studies?

A single plant or the entire plant community.

What is vegetation type?

Differences among vegetation stands such as marsh vegetation versus tallgrass prairie.

What is vegetation structure?

The spatial organization and three-dimensional arrangement of plants within a stand.

Why is vegetation measurement important in wildlife ecology?

It helps estimate carrying capacity, characterize habitat, evaluate management effects, and monitor long-term trends.

What is an indicator species in vegetation monitoring?

A plant species monitored because its presence or condition reflects habitat quality or ecological change.

What assumptions must be considered before vegetation sampling?

Knowledge of species habitat needs, clear study objectives, plant identification ability, and familiarity with sampling protocols.

What factors influence study site selection for vegetation sampling?

Topography, soil type, management history, distance to water, vegetation type, and human disturbance.

Why is a preliminary vegetation survey important?

It provides baseline information on vegetation structure and composition.

Why should vegetation sampling locations be randomly selected?

To reduce bias and ensure representative sampling.

What are quadrats used for in vegetation sampling?

Measuring density, biomass, cover, and frequency.

How does plant size influence quadrat size selection?

Larger plants require larger quadrats.

How does plant distribution influence quadrat size?

Heterogeneous or sparse vegetation requires larger quadrats.

What is the species–area curve method?

A method used to determine the smallest quadrat size that adequately captures species diversity.

How does plant variability affect sampling effort?

Greater variability requires more observations and often stratified sampling.

What proportion of a study area is typically sampled in vegetation studies?

Approximately 2 percent of the total area.

What is stratified sampling in vegetation studies?

Dividing the study area into more homogeneous sections before sampling.

Why should edge effects be avoided in vegetation sampling?

Disturbed edges such as roadsides may not represent natural vegetation conditions.

What is frequency in vegetation sampling?

The proportion of quadrats in which a species occurs.

What ecological information does frequency provide?

Species distribution and changes in vegetation composition over time.

What is density in vegetation sampling?

The number of individuals per unit area.

Why is density not the same as cover?

Density measures number of plants while cover measures space occupied.

When are distance methods used instead of quadrats?

For large or widely spaced plants such as trees.

What principle underlies distance-based density estimation?

The relationship between plant spacing and mean area per plant.

What is plotless density sampling?

A method estimating density without quadrats, suitable for randomly distributed plants.

What are advantages of plotless density techniques?

Faster sampling and less equipment required.

What is plant biomass?

The total mass of plant material above and below ground.

Why measure biomass?

It indicates forage availability, energy storage, wildfire fuel load, and hydrological processes.

What is plant cover?

The percentage of ground area occupied by vegetation.

Why is cover an important ecological indicator?

It reflects species dominance and influences erosion and wildlife habitat.

How can cover decrease while density increases?

More plants may be present but individually smaller or less spread out.

What is ground cover?

The percentage of soil surface protected by materials such as litter, rocks, or plant bases.

Why is bare ground monitored in rangeland studies?

It indicates susceptibility to wind or water erosion.

What is vegetation structure in ecological terms?

The horizontal and vertical arrangement of plants.

Why is vegetation structure important for wildlife?

It influences nesting cover, concealment, thermal regulation, and escape opportunities.

What are types of horizontal plant cover?

Canopy cover, foliar cover, and basal cover.

What is canopy cover?

The ground area covered by the outermost extent of plant crowns.

What is foliar cover?

The cover provided specifically by leaves.

What is basal cover?

The ground area occupied by plant bases.

What is DBH in tree measurement?

Diameter at breast height measured at 1.37 m above the ground.

What is gap intercept?

A measurement of spacing between canopy or basal plant gaps.

Why are canopy gaps ecologically important?

They indicate potential wind erosion and weed invasion.

What does the line-intercept method measure?

Plant cover by calculating intercepted vegetation length along a transect.

What is the formula for line-intercept cover estimation?

Cover equals intercepted vegetation length divided by total transect length multiplied by 100.

When is the point-intercept method used?

For estimating cover in vegetation shorter than about 1 meter.

What is line-point intercept sampling useful for?

Quantifying soil cover including vegetation, litter, and rock.

What are photo points used for in vegetation monitoring?

Qualitative monitoring of vegetation change over time.

What is the Daubenmire cover class method?

Ocular estimation of plant cover into predefined percentage classes.

What tools are used to measure tree canopy cover?

Spherical densitometers and sighting tubes.

What does vertical vegetation structure describe?

Plant layering and height diversity.

Why is vertical structure important for animals?

It provides multiple habitat functions such as feeding, resting, and nesting.

How is vegetation height measured in field studies?

Using a height stick within an imaginary sampling cylinder along a transect.

What is visual obstruction?

The degree to which vegetation blocks visibility at a set distance and height.

What is a cover pole or Robel pole used for?

Measuring visual obstruction and estimating grassland biomass.

Why must cover pole measurements be standardized?

Observation height and distance must be consistent for accurate comparisons.

What factors determine plant species composition?

The relative contribution of species measured using density, cover, or biomass.

What is alpha diversity?

Species diversity within a single site.

What is beta diversity?

Differences in species diversity between sites.

What is gamma diversity?

Overall diversity across a landscape or region.

How can tree age be estimated?

Counting rings, using increment borers, or applying species growth factors.

Why is forest structural complexity important ecologically?

It increases habitat diversity and supports more wildlife species.

What is radiometric vegetation measurement?

Remote sensing measurement of visible, infrared, and ultraviolet reflectance.

What is leaf area index?

The area of leaves per unit ground area.

What are vegetation indices?

Remote sensing metrics used to assess vegetation amount, structure, and condition.

What does NDVI measure?

Vegetation greenness based on differences between near-infrared reflection and red light absorption.

What ecological applications does NDVI have?

Monitoring vegetation density, plant health, drought, and seasonal phenology.

What is the green wave hypothesis?

Migrating animals track peak forage quality during spring green-up.

How did bison influence vegetation green-up in Yellowstone?

Intense grazing created grazing lawns that greened earlier and remained productive longer.