Forestry, Midterm - Finals

Sustainability

the property of a biological system to remain biodiverse and produce indefinently

How do trees combat soil erosion?

• Trees intake water from soil, making the soil stronger and more cohesive

• Tree’s provide root reinforcement → roots lock the soil into place

The downside to using plantation forests to prevent erosion and land-slides

• the land is vulnerable to landslides after being harvested

• Not all species are adapted to be planted on erodable land

Why are trees planted in erodible areas?

1) trees combat soil erosion by making the soil dryer

2) trees reverse the degradation of soil by

Umbrella effect

Trees act as an umbrella and minimize water from falling onto soil

• reduced water reduces chances of landslides and erosion

Surface Erosion

• The removal of soil and rock particles from the Earth’s surface by natural forces like wind, water, and gravity

• exposed soil on steep hill country is vulnerable to surface erosion from heavy rain

• Sediment from surface erosion can

• can be controlled by clear-felling practices

Landslides

mass movement of forested debris and sediments carried by a body of water and gravity

• moves as one body of mass

• a mechanism of moving sediment

Conditions for landslides

• soil is weakened by a disturbance (earthquake, heavy rain, deforestation)

• On a steep slope so gravity acts on it

Hazards of landslides

• can cause immediate damage to people and the environment

• contaminate water sources

• damage infrastructure

• disrupt forest services

Two common types of landslides in New Zealand

• Shallow landslides

• Debris flow

Shallow landslides

• landslide caused by slope failure on shallow soil caused when tree roots don’t reach deep enough to reach the slip surface

  • moves very quickly

  • runny texture

  • cause by high intensity rain

Debris Flow

• rapid mass movement of earth and rock mixed with water

  • is very viscous

  • typically moves into a stream channel

Key factors for implementing Sustainable Forest Operations (SFO)

1)economic

2)ergonomic - who is working in the forests and how

3) environment

4) people/society- people outside the forests

5) Quality and optimization

Social license to operate

The level of acceptance or business activity

managing public or political risks around resource projects and business

The overlap between a legal license and society’s expectations

• built on enabling forest owners and neighbors

People and Society in contribute to SFO implementation through

• provisioning services and functions

• Regulation and maintenance services and functions, regulation of ecosystem functions

• cultural services and functions

• Employment and services

What are we trying to sustain in forests

1) Provisioning services

• Harvest volume, maximizing economic productivity

2) Non-Provisioning services

• Any product other than timber that is produced in forests

  • forest foods, fish/game, medicinal plants, animal forage

3) Regulatory services

• services that maintain ecological and biological systems

  • Mitigating climate change via sequestering carbon

  • reducing erosion

  • mitigating floods

4) Cultural services

• maintaining forest culture like..

  • forest recreation

  • aesthetics and spiritual appreciation

  • biodiversity and conservation

Challenges to implementing SFO

1) Harvesting

2) land use conservation

3) pests and diseases

4) workplace fatalities

5) Climate Change