Common Restoration Techniques

Question 1

What are the 5 categories of restoration techniques that managers use?

Answer 1

Hydrological techniques 
Biological techniques 
Site preparation 
Woody vegetation control
Prescribed burning

Question 2

What are the 4 hydrological restoration techniques we discussed?

Answer 2

Water interception and retention
Restore hydrology
Grade control
Reconnect waterways

Question 3

Issue 1: increased runoff and erosion due to loss of vegetation, compaction, reduced infiltration, interception, and storage/retention (5 points)

Answer 3

Solution: increase water retention by,

• Using cover crops
• Using green manure
• Creating grass waterways
• Planting rain gardens and deep rooted native plants

Question 4

Cover crops

Answer 4

A hydrological restoration technique that involves planting vegetation to increase water interception and reduce erosion

Question 5

Green manure

Answer 5

Hydrological restoration technique that involves tilling cover crops into soil to increase soil organic matter and thus water retention

Question 6

Grass waterways (2 points)

Answer 6

Natural drainage is graded and shaped to form a shallow channel then planted with sod-forming grasses.

This grass then intercepts runoff, filters sediment/nutrients/contaminants from fields, prevents gullies from forming and provides habitat for animals

Question 7

Benefits of rain gardens and planting deep-rooted native plants

Answer 7

Intercepts run off, filters contaminants and nutrients, and increases infiltration in areas with high impenetrable cover

Question 8

Issue: in arid ecosystems, invasive woody vegetation can reduce water retention through increased rates of transpiration (4 points)

Answer 8

Solution: remove invasive woody plants by:

• harvesting
• brushing
• herbicide
• prescribed fire

Question 9

Issue: drainage systems dewater sites to improve conditions for crops. The resulting changes in nutrients and decreased oxygen in soils disfavour many native plants

Answer 9

Solution: disable ditches and tiles to restore underground hydrology

Question 10

Issue: channelization and gradient increase to streams in order to de-water channels. This increases erosion, downcutting, and removes natural features for animal/plant habitat (4 points)

Answer 10

Solution: grade control

Build grade control structures such as rock vortex weirs and low-drop grade control structures

They can be natural or artificial

They are barriers that produce reduced gradient in streams and direct flows to the centre of the stream bed

Question 11

Issue: dams and dykes have reduced flood frequency, disconnecting flood plains from their stream channel (removing maintenance disturbance regime) (4 points)

Answer 11

Solution: remove or breach dams and dykes

Often a legal rather than a practical challenge

Flood events will build up their own natural dykes with the flood process

Some issues might occur at the onset before natural dykes are built up (eg. Flooding of buildings etc. near area)

Question 12

Hydrological issues that managers focus on (4 points)

Answer 12

Leaky watershed (high run-off, erosion and sedimentation)

Woody plants increasing transpiration

Dewatered sites from drainage systems

Channelization and gradient increases in streams

Question 13

What are the 3 biological restoration techniques we discussed?

Answer 13

Cover crops
Animals
Bioremediation

Question 14

What are biological restoration techniques?

Answer 14

The use of plants, animals, and other living organisms to achieve restoration ends

Question 15

Reducing invasive/non-native plants can be achieved using: (3 points)

Answer 15

Cover crops to reduce erosion, shade invasives (smother crops) and protect slower growing natives from freezing and rapid drying (nurse crops)

Animals can be used to remove invasives/non-native plants that are herbaceous (grazing) or woody (browsing)

Question 16

Bioremediation (2 points)

Answer 16

The use of living organisms to consume and break down contaminants

This often entails using microorganisms but can entail using rapidly growing plants called phytoremediation

Question 17

What can bioremediation be used to do? (2 points)

Answer 17

Absorb contaminants - if organic, can later be used as mulch, if toxic, can later be disposed of

Increase soil organic matter and stability - enables soils to tie up contaminants

Question 18

What aspects of ecosystems are affected by disturbance regimes such as fire? (3 points)

Answer 18

Species composition
Structure
Ecological processes

Question 19

How does fire affect ecosystems? (2 points)

Answer 19

Through altering the successional stage

Through altering the chemistry

Question 20

How does fire alter the successional stage of an ecosystem? (3 points)

Answer 20

Reduces fire intolerant species (those not adapted to fire regime=non-natives)

Stimulates germination of fire adapted species

Reduces woody vegetation while creating wildlife trees (standing dead wood) or coarse woody debris (dead and down trees)

Question 21

How does fire alter the chemistry of an ecosystem? (2 points)

Answer 21

Releasing nutrients in vegetation

Reducing soil acidity

Question 22

Prescribed burns are generally conducted according to 2 conflicting criteria: (3 points)

Answer 22

Matching historical fire regimes (in terms of frequency, severity, size, and patchiness)

Ensuring conditions are conductive to human safety (low wind/temperature, high moisture)

Human safety often takes precedent

Question 23

How do we avoid the conflicts between matching historical fire regimes and human well-being? (3 points)

Answer 23

We do prescribed burning at various times of year (not just in the wet season)

This allowed us to increase the potential for desirable outcomes and prevent danger as managers are more selective in choosing safe conditions

Also, they are not forced to do all their burning in one season and can therefore have smaller, more manageable fires even if the hot season

Question 24

What are the 2 site preparation techniques we discussed?

Answer 24

Reduction of invasive/non-native species using mechanical, chemical, or prescribed burning techniques

Soil modification

Question 25

What is the purpose of site preparation techniques?

Answer 25

To alter the conditions to favour native species of plants

Question 26

What are the soil amendments in site preparation? (4 points)

Answer 26

Increasing OM (eg. Green manure)

Reducing acidity (eg. Applying lime)

Reducing alkalinity (eg. Applying sulfur)

Reducing compaction (eg.planting deep-rooted species, subsoiling)

Question 27

What are some techniques to remove woody vegetation? (4 points)

Answer 27

Prescribed burning (encroachment and competition)

Chemical removal

Mechanical removal like harvesting, brushing, girdling

Note: mechanical removal is often followed by chemical removal