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Forest

While it is true that trees dominate - they are the biggest organisms present there, there are many of them, and they dont move about - a forest is in fact a community of not just plants and animals, but micro-organism as well

WWF

Types of Forests

Tropical Greatest diversity Large forest canopy Decomposition is rapid Nutrient poor soil

Temperate Seasonal weather Soil is fertile, enriched with decaying litter

Boreal Short, moist and moderately warm summers and long cold

and dry winters Soil is thin, nutrient poor and acidic

Forests

Old growth. Ancient or virgin forest Trees have obtained a great age Large dead trees and logs Developed understory Gaps in canopy

Secondary forest Regrowth after a major disturbance Fire, insect infestation, wind throw, or timber

harvest Tertiary forest

Forest is disrupted

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Deforestation

Deforestation is the process whereby natural forests are cleared through logging and/or burning, either to use the timber or to replace the area for alternative uses.

12-15 million hectares of forest are lost each year, the equivalent of 36 football fields per minute,

Causes of Deforestation Conversion of forests

Lumber Pulp (paper) Palm oil and soy plantations Agriculture Cattle Roads and other infrastructure

Degradation Fires Illegal and unsustainable logging

Buy good wood - wood that has been obtained through legal practices and sustainability

Fuel harvesting (wood and charcoal) Climate change

Deforestation

Reduction in biodiversity Release of greenhouse gas emission

(CO2) Disrupted water cycles Increased soil erosion Disrupted livelihoods

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Deforestation

Reduction in Biodiversity When forest cover is removed, wildlife is

deprived of habitat and becomes more vulnerable to hunting. Considering about 80% of the worlds documented species can be found in tropical rainforests, deforestation puts at risk a majority of the Earths biodiversity

Deforestation

Release of greenhouse gas emissions Deforestation causes 15% of global

greenhouse gas emissions Carbon dioxide emissions represent up

to one third of the total CO2 emissions due to human causes

Deforestation

Disrupted water cycles As a result of deforestation. Trees no

longer evaporate groundwater, which can cause the local climate to become drier.

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Deforestation

Increased Soil Erosion

Accelerates rates of soil erosion, by increasing runoff and reducing the protection of the soil from tree litter

Deforestation

Disrupted livelihoods Millions of people rely directly on forests

through small-scale agriculture, hunting and gathering, and by harvesting forest products such as rubber and Brazil nuts. Deforestation continues to pose severe social problems in places, sometimes leading to violent conflict.

Conservation

We abuse land because we regard it as a commodity belonging to us. When we see land as a community to which we belong, we may begin to use it with love and respect.

Aldo Leopold

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Conservation

To waste and destroy our natural resources, to skin and exhaust the land instead of using it so as to increase its usefulness, will result in undermining in the day of our children the very prosperity which we ought by right to hand down to them.

Theodore Roosevelt

WOOD - Lumber

Wood

Hardwoods Angiosperms or flowering plants Maple, oak, walnut, teak, etc. More lignin

Softwoods Gymnosperms or conifers Pines, spruce, redwood, fir, etc. Fewer cell types

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Wood

Secondary xylem Sapwood

Transports water

Heartwood Dead Tannins, gums & resins Preferred for wood (drier,

more resistant to decay)

Ray cells

Wood - Tree rings

Larger and smaller xylem cells

Wood

Temperate Annual temperature and moisture Measures spring and summer growth Dendrochronology

Tropics Measures wet and dry periods

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Wood Characteristics

Color Porosity Grain Figure Density

Wood Characteristics

Color Black Yellow Brown Green Red Purple

Wood Characteristics

Porosity Distribution of cells

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Wood Characteristics

Grain Alignment of xylem cells

Wood Characteristics

Figure Number of rays, knots, burls etc.

Wood Characteristics

Density Mass of wood Balsa 170 kg/cu m Cedar 350 Fir 530 Maple 750 Ebony 960-1100 Lignum vitae 1300

Above 1000 sinks in water

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Uses of Wood

Lumber Veneers

Plywood Engineered wood Chipboard

Particle board Cork Firewood Charcoal Paper

Uses of Wood

Lumber Veneers

Plywood Engineered wood

Composite Chipboard Paralam

Uses of Wood

Particle board Cork Firewood Charcoal Paper

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Paper

Early writing on clay tablets Egyptians used papyrus

Strips plant flattened, pressed and dried Greeks and Romans until 4th century

Parchment (skins of sheep etc.) Chinese rice paper from rice plants Chinese hemp paper

Paper

Paper from wood Hand process and hand molds Chinese 105 A.D. Japan 610 A.D. Arab world 800 A.D. Spain 1150 A.D. Gutenberg Printing Press

Paper

17th and 18th centuries greater demand for paper

Mechanized processes in 18th century Molds Wood pulp

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Papermaking

Harvesting trees Cutting logs and removing the bark Grinding and chipping the wood Cooking the chips in a chemical digester

Bisulfites and acids Makes pulp Dissolves lignin

Wash and bleach with chlorine

Papermaking

Beat and smooth the pulp Add binding agents (aluminum sulfate) Fourdrinier Machine

Wire screen with pulp Removes water and makes paper

Paper

1 billion trees cut per year for paper Deforestation U.S. 1/3 of production and use of paper 730 pounds/year 2 pounds/day 43% for newsprint 40% of municipal garbage

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Paper

Alternatives Cotton and linen Jute Hemp Kenaf (hibiscus species) Recycled paper 1 box of facial tissue for every family make

from 100% recycled paper will save 280,000 trees

Great Law of the Iroquois

"In our every deliberation, we must consider the impact of our decisions on the next seven generations."