Lecture 8: Range Inventory And Monitoring

Question 1

Range Inventory

Answer 1

Systematic identification, mapping, and quantification of ecosystem biophysical components, and the human infrastructure needed to manage livestock

Question 2

Rangeland monitoring

Answer 2

Evaluating the impact of grazing and browsing on a plant community to facilitate management changes. Can also be the interpretation of range inventory data

Question 3

Which level does inventory occur at?

Answer 3

Occurs at the level of the landscape

Question 4

What is included in an inventory?

Answer 4

• total area
• pasture size and fencing
• infrastructure, roads, buildings
• water, natural and artificial sources
• livestock and wildlife
• vegetation and soils

Question 5

What does monitoring include?

Answer 5

• precipitation
• production
• plant community and ecosystem health
• grazing use
• animal production
• profits
• changes in wildlife populations

Question 6

Mapping

Answer 6

Focuses on the vegetation present. Usually an aerial photo via GIS. From this we can classify vegetation broadly and estimate biomass

Question 7

Vegetation

Answer 7

What types of plant communities are present? This includes spices composition and abundance. Plant classification includes community types and their associations. For site selection, we assume it is representative, and that if we manage for the sensitive areas, adequate management will be ensured at all areas.

Question 8

Vegetation cover and density

Answer 8

Two different types of data

• density has to do with spatial arrangement, and how close they are.
• cover has to do with the actual biomass

Question 9

Frequency

Answer 9

The proportion of fixed area plots with a given plant species. This is easy to measure, but is not good for management

Question 10

Height

Answer 10

A crude indicator of plant vigorous. It is often used to assess habitat quality

Question 11

Biomass production/productivity

Answer 11

The ANPP is the annual net primary production. This is the total new plant growth in a growing season

Question 12

Herbage

Answer 12

Total plant biomass of all grasses and Forbes at one point in time

Question 13

Forage

Answer 13

Total plant biomass that is acceptable for animal consumption

Question 14

Browse

Answer 14

Leaves and twigs of shrubs and trees that are available and acceptable for animal consumption

Question 15

Utilization

Answer 15

The amount of production removed by herbivores

Question 16

Forage quality

Answer 16

This is the crude protein and the acid digestible fibre

Question 17

Inventory data collection methods depend on

Answer 17

Cost, time, personnel, data needs, and variability

Question 18

Infrastructure: pasture

Answer 18

Land areas exposed to herbivores at one point in time. Limits are usually fenced, includes the number and size of pastures, and the distribution of location, elevation, and topography

Question 19

Infrastructure: fencing

Answer 19

Perimeter vs. Cross fencing, permanent or electric, and game proof or cattle proof

Question 20

Infrastructure: water

Answer 20

Number of sources, location, distribution, type, and quality of water

Question 21

Stages of grazing induced retrogression

Answer 21

1. Reduction in vegetation stature/ height
2. Decline in herbivore preferred plant species
3. Replacement of preferred species with avoided and/ or grazing tolerant species
4. Loss of litter, soil xerification
5. Further composition shifts from mesic to xeric adapted species
6. Extensive litter loss, leading to accelerated erosion, loss of OM, and decline in soil quality

Question 22

Plant responses to grazing

Answer 22

Decreasers: decline in abundance under any grazing

Increasers: peak abundance under light to moderate grazing

Question 23

Trend

Answer 23

The direction of change in range condition, used traditionally to describe conditions for livestock.

Question 24

Linear retrogression model

Answer 24

Assumes response to grazing is predictable and reversible

Question 25

Advantages of linear models

Answer 25

Simple to use, easy to identify management implications and it works well where rangeland resilience is high and where a distinct climax is apparent

Question 26

Problems with linear model

Answer 26

In many areas, climax is unknown, unrealistic to manage for, and may not be the most desirable community (max diversity at intermediate disturbance). Linear models work poorly in some systems and are ineffective in semi-arid areas with long unpredictable response times

Question 27

Problems with the use of enclosures and benchmarks

Answer 27

Eliminating grazing is unnatural, and causes stagnation, and a reduce in production and diversity. Exclosures can also be small and isolated, making it hard to extrapolate to coarser scales. They can trap snow, attract birds and rodents. The starting range conditions are often poor. Ungrazed remnants are limited to lower quality range sites

Question 28

Non linear retrogression model

Answer 28

Grazing response is not linearly reversible due to physical alteration of the environment, or complex vegetation responses. There is a threshold between states

Question 29

Calculation of range condition

Answer 29

Condition is determined by comparing the abundance of plant species in the current community with the ungrazed state that may be expected for a given range site

Question 30

Ungrazed state is…

Answer 30

• Climax: stable native community formed in the absence of grazing, with no introduced species
• Benchmarks: areas protected from grazing, via human made fenced enclosures, or natural islands
• PNC: potential natural community, one that includes naturalized plants. Suggests that the climax state may not be the best

Question 31

Range trend

Answer 31

Actual quantified changes in condition rating over time, at last 2 separate measurements

Question 32

Apparent trend

Answer 32

This is the inferred trend based on a single assessment, using indicators. Indicators are the characteristics that provide meaningful information for interpreting levels of animal use, range condition, trend, etc.

Question 33

Range health

Answer 33

The ability of current vegetation to maintain long-term productivity and ecological integrity for a given state

Question 34

Multiple stable states

Answer 34

Occurrence of several stable communities for a particular range site, each separated by distinct ecological thresholds

Question 35

State and transition models

Answer 35

Relate alternative stable states to one another based on environment and disturbances. This shows the dangers of improper management, and h opportunities available to enhance management

Question 36

Riparian health

Answer 36

Channel sinuosity and bank profile stability based on steam profile and vegetation composition, and a host of other ecosystem functions

Question 37

Site composition threshold

Answer 37

Minimum plant cover and litter needed to prevent accelerated erosion