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Presentation on theme: "10-1."— Presentation transcript:

1 10-1

2 Housekeeping Items I’m still working on the mid-terms and will get them back as soon as I can. I am swamped with marking at the moment. Today we’re going to look at forestry issues. We’re a week behind so I will try to catch us up as we have some important subjects to cover towards the end of the course. In moving towards more ecologically responsible forms of forestry, see the profile of Tzeporah Berman on p Tzeporah has played an integral part in Greenpeace and Forest Ethics.

3 Upon completing this chapter, you will be able to
Describe the basic functional processes of trees and their role in biogeochemical cycling Summarize the principal types of forest biomes, especially those indigenous to Canada Describe the ecological roles and economic contributions of forests Trace the history and scale of forest loss and identify the current drivers of deforestation Outline the major methods of harvesting timber Explain the fundamentals of forest management, and identify forest management agencies in Canada and internationally

4 Central Case: Battling over the last big trees at Clayoquot Sound
1993: The largest act of civil disobedience in Canadian history 12,000 protestors blocked loggers from cutting ancient trees in Clayoquot Sound on Vancouver Island, British Columbia Old-growth forests = complex primary forests in which the trees are at least 150 years old Jobs depended on the timber industry Iisaak, meaning “respect”, became a guiding principle for forestry in the area Variable retention harvesting = logging selectively to retain a certain percentage and characteristics of the forest ecosystem

5 The Forest and the Trees

6 The Forest and the Trees
Forests cover about 31% of Earth’s land surface Provide habitat, maintain soil, air, and water quality, and play key roles in biogeochemical cycles

7 Trees have several basic requirements
For photosynthesis to occur An amenable temperature Air Light Soil Water 10-7

8 Trees have several basic requirements (cont’d)
Macronutrients – required in large amounts Micronutrients – required in small amounts Transpiration – water loss from leaf surface, cools the plant as well as assisting in the movement of nutrients Water drawn up through xylem by adhesion and cohesion Useful to plant trees in close proximity to crops to make water more accessible to crops 10-8

9 There are three major groups of forest biomes
Boreal forest High-latitude forest Cold, dry climates with short growing seasons Temperate forest (including our rainforest) Mid-latitude forest Seasonal climate (winter season vs. summer growing season) Tropical forest Equatorial-latitude forest Wet, tropical climate

10 Forests grade into open wooded lands
Drylands: Shrublands = wooded areas covered by shrubs and occasional taller trees (e.g. tundra) Savannah = open area dominated by grasses with widely scattered trees Grasslands = lands dominated by grasses and non-woody vegetation

11 Canada is a steward for much of the world’s forest
402 million hectares of forested and other wooded land is 25% of the world’s natural forest Canada has the highest amount of forested land per capita in the world More than 50% of Canada’s primary forest remains more or less intact

12 Canada’s forests are varied
402 million hectares of forested and other wooded land is 25% of the world’s natural forest Forests of the north: Boreal forest (taiga) is the largest forested region of Canada Every province except Nova Scotia and Prince Edward Island Forests of the west: Forest regions: Subalpine, montane, coast, Columbia Forests of the east: Forest regions: Deciduous, Great-Lakes-St.Lawrence, Acadian

13 Canada’s Forest Regions (source: Global Forest Watch)

14 Horizontal structure/ storeys of the forest
Canopy – upper level of leaves, woodland area has a more open canopy

15 Forests are ecologically valuable
One of the richest ecosystems for biodiversity Structural complexity houses great biodiversity Some animals adapted for living in canopy, others specialize on the sub-canopies Shrubs and groundcover plants of the understory are home to still more organisms Fallen leaves and branches called litter, house still others Forest edge can be quite different from habitat in the forest core

16 Trees provide ecosystem services of value to people
A forest provides many ecosystem services Stabilizes soil and prevents erosion Slows runoff, lessens flooding, purifies water Stores carbon, releases oxygen, moderates climate

17 Harvesting Forest Products

18 Forest products are economically valued
Benefits: fuel, shelter, transportation (ships), paper Helped society achieve a high standard of living Softwood = timber harvested from coniferous trees Hardwood = timber harvested from deciduous trees NTFPs = non-timber forest products such as medicinal, herbal, decorative and edible products (often undervalued in forest planning)

19 Timber is harvested by several methods
Clearcutting method – all trees in an area are cut, leaving only stumps Most cost-efficient Greatest impacts on forest ecosystems Mimics natural disturbances such as fires Enhances soil erosion 10-19

20 Timber is harvested by several methods (cont’d)

21 Timber is harvested by several methods (cont’d)
Selection systems = only select trees are cut Single tree selection = widely spaced trees are cut Group tree selection = small patches of trees are cut All methods disturb habitat, except certain forms of selective logging such as practiced at Wildwood near Yellowpoint by the now-deceased Merv Wilkinson Change forest structure and composition Increase erosion, siltation, runoff, flooding, landslides See: how_it_works.php

22 Plantation forestry has grown in North America
Reforestation = planting of trees after logging Afforestation = planting of trees where forested cover has not existed for some time Even-aged trees =all trees are the same age Maximum sustainable yield = cutting trees shortly after they have gone through their fastest stage of growth, and trees often grow most quickly at intermediate ages

23 Land Conversion and Deforestation

24 Land conversion and Deforestation
Deforestation = the clearing and loss of forests People have cleared forests for millennia Clearing of land for farming one of the first significant human environmental impacts Alters landscapes and ecosystems “Pioneers Clearing the Land” by C.W. Jeffreys

25 The growth of Canada and the U. S
The growth of Canada and the U.S. were fueled by land clearing and logging Deforestation propelled growth throughout North America Cleared for farming Then wood used to fuel furnaces of industry Principal cause of deforestation in Canada is agriculture

26 Agriculture is the major cause of conversion of forests and grasslands
Agriculture covers more of the planet’s surface than forest Principal driver of land conversion today Swidden agriculture = small area of forest cleared and crops planted Sustains only one or two seasons of planting Soil depleted quickly 7 years required to replenish soil in original clearings to support crops or forests

27 Former rainforest (source: Wild Madagascar)

28 Livestock graze one-fourth of Earth’s land surface
Most cattle today raised in feedlots, but have traditionally been raised by grazing on open rangelands Grazing can be sustainable if done carefully and at low intensity Poorly managed grazing impacts soil and grassland ecosystems Ranchers and environmentalists have joined to preserve ranchland against development and urban sprawl

29 Bad practices and other pressures have led to deforestation
Deforestation has altered the landscapes and ecosystems of much or our planet Forest can be harvested sustainably but it hasn’t always happened Impacts are greatest in tropical areas and in dryland regions Deforestation also adds carbon dioxide to atmosphere Fastest rates of deforestation are in tropical rainforests of Latin America and Africa 10-29

30 Deforestation is proceeding rapidly in many developing nations
Uncut primary tropical forests still remain in many developing countries Advanced technology has allowed the exploitation of resources faster than in the past Often these countries impose few or no restrictions on logging Often timber is extracted by foreign corporations FIGURE 10.10

31 weighing the issues Logging here or there Imagine you are an environmental activist protesting a logging operation that is cutting old-growth trees near your hometown. If the protest is successful, the company will move to a developing country and cut its primary forest instead. Would you still protest the logging in your hometown? Would you pursue any other approaches?

32 Forest Management Principles

33 Forest Management Principles
Forestry (silviculture) = a professional field of managing forests by balancing forests as ecosystems and as sources of wood products Harvesting = the removal of material from the resource Should not occur at a rate that exceeds the capability of the resource to replenish or regenerate itself

34 Public forests in Canada are managed for many purposes
Canadian Forest Service preserves timber on Crown lands Crown land used for timber and non-timber forest products Multiple use = policy where forests were to be managed for recreation, wildlife habitat, mineral extraction, and various other uses wooded areas covered by shrubs and occasional taller trees (e.g. tundra)

35 Public forests in Canada are managed for many purposes (cont’d)
National Forest Strategy for Ecosystem-based management Better environmental, social, and economic sustainability of forest communities through legislation and policies Recognizing rights of Aboriginal peoples Diversification of markets for forest products Better skills and knowledge of forest practitioners Engaging Canadians in sustainability through urban forests Support private woodlots for forest sustainability National forest reporting system

36 Today many managers practise ecosystem-based management
Ecosystem-based management = managing the harvesting of resources to minimize impact on the ecosystems and ecological processes Carefully managing ecologically important areas Protecting some forested areas There is some of this going on in Clayoquot Sound It is challenging for managers to determine how to implement this type of management Ecosystems are complex, and our understanding of how they operate is limited

37 Adaptive management evolves and improves
Adaptive management = systematically testing different management approaches and aiming to improve methods; originated by C.S. (‘Buzz’) Holling Monitoring results and adjusting methods as needed A fusion of science and management Time-consuming and complicated A guiding principle for forest management in Canada West Arm Demonstration Forest Experiments Donna Creek Biodiversity Project Grizzly Bear Habitat Project

38 Fire is a natural phenomenon in forests
Many ecosystems depend on fire Ecosystems dependent of fire are adversely affected by its suppression Ground fires = the litter layer itself burns, as opposed to crown fires Crown fires = the upper tree canopy is ignited 10-38

39 Fire policy has stirred controversy
For over 100 years, all forest fires were suppressed But many ecosystems depend on fires Fire suppression allows woody accumulation, which produces kindling for future fires Housing development near forests and climate change will increase fire risk

40 Fire policy has stirred controversy (cont’d)
Prescribed (controlled) burns = burning areas of forests under carefully controlled conditions Effective May get out of control Impeded by public misunderstanding and political interference

41 Fire policy has stirred controversy (cont’d)
Removal of dead trees following a natural disturbance Seems logical, but is really destructive Snags (standing dead trees) provide nesting cavities for countless animals Removing timber from recently burned areas increases erosion and soil damage

42 weighing the issues How to handle fire? A century of fire suppression has left vast swaths of forested lands in danger of catastrophic wildfires. Yet we will probably never have adequate resources to conduct careful prescribed burning over all these lands. Can you suggest any solutions to help protect people’s homes near forests while improving the ecological condition of some forested lands? Do you think people should be allowed to develop homes in fire- prone areas?

43 Sustainable forestry is gaining ground
Sustainable forestry certification = only products produced sustainably can be certified International Organization for Standardization (ISO), Forest Stewardship Council (FSC) have different standards Consumers look for logos to buy sustainably produced timber As a result of environmental campaigns and negotiations, companies such as Home Depot sell sustainable wood This encourages better logging practices

44 Conclusion Forests and other terrestrial biomes provide crucial ecosystem services that have economic value as well Resources must be managed sustainably to avoid overexploitation and overharvesting There are federal and regional agencies to oversee and manage publicly held land and natural resources Resource management policies consider sustained yield, multiple use, timber production, recreation, wildlife habitat, and ecosystem integrity Public support resulted in parks, wilderness areas and other reserves

45 QUESTION: Review If an area is managed for Maximum Sustained Yield, and the area can support 100 organisms, how many organisms will be allowed to remain in the area? a) 100 b) 75 c) 50 d) 25 Answer: c

46 QUESTION: Review Which of the following is not part of the ecological value of forests? a) Erosion prevention b) Decreased flooding c) Carbon storage d) Climate moderation e) All of the above are values of forests Answer: e

47 QUESTION: Review Which of the following statement regarding forest management is false? a) Deforestation in Canada has occurred for centuries b) Timber companies move on after an area is deforested c) Tropical countries have lost the majority of forests so timber companies won’t be going there d) Governments in developing countries help logging companies at the expense of native people Answer: c

48 QUESTION: Review Which agency preserves timber on Crown lands?
a) Canadian Wildlife Service b) Canadian Forest Service c) Bureau of Land Management d) Ministry of Forests and Range Answer: b

49 QUESTION: Review Tree harvesting by clear-cutting….
a) Cuts all trees in an area, leaving only stumps b) Cuts most trees, but leaves some to produce seeds c) Cuts most trees, but leaves some to shelter seedlings d) Produces uneven-aged tree stands Answer: a

50 QUESTION: Review The National Forest Strategies for included all of the following, except: a) Ecosystem-based management b) Diversification of markets for forest products c) Increased harvesting under times of economic stress d) Recognizing legal rights of Aboriginal peoples Answer: c

51 QUESTION: Interpreting Graphs and Data
What is the largest cause of deforestation in Canada today? Development Agriculture Hydroelectricity Forest roads Answer: b

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