Lecture 8_Forest Ecosystem Health and Vitality

The Montreal Process Last version 2015

1) Conservation of biological diversity; 

2) Maintenance of productive capacity of forest ecosystems; 

3) Maintenance of forest ecosystem health and vitality; 

4) Conservation and maintenance of soil and water resources;

5) Maintenance of forest contribution to global carbon cycles; 

6) Maintenance and enhancement of long-term multiple socio-economic benefits; 

7) Legal, institutional and economic framework for forest conservation and sustainable management

Criterion 3: Maintenance of forest ecosystems health and vitality

Two Indicator:

1. The area and percent of forest affected by biotic processes and agents, 

2. The area and percent of forest affected by abiotic agents (e.g. fore, storm, land clearance) beyond reference conditions.which assess the overall health and vitality of forest ecosystems.

The Montreal Process Last version 2015

1) Conservation of biological diversity; 

2) Maintenance of productive capacity of forest ecosystems; 

3) Maintenance of forest ecosystem health and vitality; 

4) Conservation and maintenance of soil and water resources;

5) Maintenance of forest contribution to global carbon cycles; 

6) Maintenance and enhancement of long-term multiple socio-economic benefits; 

7) Legal, institutional and economic framework for forest conservation and sustainable management

Criterion 3: Maintenance of forest ecosystems health and vitality

Two Indicator:

1. The area and percent of forest affected by biotic processes and agents, 

2. The area and percent of forest affected by abiotic agents (e.g. fore, storm, land clearance) beyond reference conditions.which assess the overall health and vitality of forest ecosystems.

Criterion 3 problems

1. There is no clear definition of ‘forest ecosystem health and vitality’ 

2. Both indicators refer to a state known as ‘beyond reference conditions’. Hard to define, since it represents astatic view of the environment that is not present

3. Some disturbances biotic and abiotic are essential for the maintenance of values such as biodiversity 

The evolving concept of Forest health

must consider variables like Spatial, Temporal, Scale, and Anthropogenic perspective isntead of ecosystem-approach.

Fores can be viewed as dynamic social-ecological systems

Forest Biotic disturbances:

Parasitism: specialists or generalists

Parasite outbreaks: conditions that allow insects to increase their population

could have many drivers which will reduce trees defences (root diseases weaken conifers which allow bark beetles to infect)

Grazing

Pathogens, Saprophytes, Symbiotic and Endophytic (enhances plant immunity + resilience)

Forests need a healthy amount of diseases

The disease Triangle

A framework that studies the interaction of environmental factors, the host, and the parasite.

root diseases consequences on the forest ecosystem:

1. Killing trees and creating canopy gaps, 

2. Promoting regeneration and the growth of shade-intolerant species, 

3. Cause different levels of mortality in different tree species 

4. Increase heterogeneity, diversity and resilience by creating patches composed of different species and age classes

wildlife trees as animal hotels

1. Snags 

2. Nesting cavities

3. Improve wildlife habitat

Anthropogenic activites in forest pest outbreaks

responsible for some of the worst forest pest outbreaks

1. Introduction of new invasive alien species; 

2. Management practices that are conducive to insect or pathogen reproduction survival or spread; ,(monoculture plantations) 

3. Climate change

Invasive Alien Species

Chestnut blight, a fungal pathogen introduced accidentally from Asia to North America, causes irreversible ecosystem damage. Trees such as oaks replaced chestnuts as the dominant tree species. Cause reduction in leaf-litter processing and decreased abundance of cavity-nesting birds

Impact of forest management practices on forest pest outbreaks:

mismanagement of forest like harvesting, reforestation, fire control and plantation homogeneity: major drivers of biotic disturbances

1. An outbreak of the mountain pine beetle is a good example of an indigenous insect undergoing a major outbreak, A combination of logging, better control of forest fires, and climate change has resulted in a perfect storm that has created an unprecedented outbreak covering 35 million ha in 19 US states and two Canadian provinces in western North America

2. unusually hot summers with milder winters led to the expansion of the beetle infestation

3. caused the forest to not be a net carbon sink but a carbon source

Biotic Process with Climate change

• Assisted migration principle: this has been proposed but is a controversial idea, example is the movement of Florida torreya from their current restricted range in the North of Florida to the northern Midwest of the USA

• Pest and Pathogen will also expand in response to climate change 

• Forest modelling in hot action now in prediction of future changes in forest at the local and global scale

Abiotic disturbances in forests

positive or negative

interaction between multiple processes is possible and common

1. Geological disturbances: volcanoes, earthquakes and tsunamis; 

2. Geomorphological disturbances: landslides, flood and blowing sand; 

3. Soil problems: infertility, salinization and waterlogging

4. Climate problems: windstorms, droughts, extreme heat, extreme cold and seasonal frost fires

5. Anthropogenic problems: air pollution; 

6. Desertification 

Effects of abiotic disturbances in forests:

1. Climate and weather related effects

2. Windstorms: uprooting and snapping trees, can transport saltwater

3. Ice, hail and snow: freezing rain and red belt damage

4. Drought and excessive heat

5. Waterlogging

6. Air pollution 

7. Fire

Red belt damage

1. warm and dry winds during winter, reddening caused by needle desiccation (drying)

Forest Fires

• Greatest challenge in forest management, but a necessary process in many forests,

• Prescribed fires can reduce the chances of fires moving from the ground to the canopy through laddering

• Fires resistant species can be favoured in plantations - those with thick barks

• Serotinous Cones can only open and release seeds after they were heated

• Other trees seeds got hard coats and are cracked by fire 

• Some plants sprout after fires from epicormics buds which were set deep in the bark of the stem and branches, or basal stems, roots and horizontal rhizomes

The Raunkiær system for plant life forms

Classification method for plants based on the position of perennating organs (organs that allow plant to survive through disturbances) 

Five life forms based on the position of their dormant buds (Raunkiær)

1. Phanerophytes: Buds above ground on woody stems or branches. Ex: trees and shrubs ( Oaks, pines, other trees)

2. Chamaephytes: buds close to the ground, at soil level or just above. Ex: Low shrubs, some alpine plants like Alpine Bearberry

3. Hemicryptophytes: buds are located at ground level, protected by L horizon or soil. Like grasses, herbs (Canada goldenrod)

4. Crytophytes: buds are underground in the form of bulbs, tubers, or rhizomes. (Canada lily tulips, crocuses) 

5. Therophytes: plants that complete their life cycle in a single season. Ex: Weeds, annual crops