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The Temperate Deciduous Forest Biome. Robinson Forest, Eastern Kentucky. Ecological importance of forests Forests are WATERSHEDS: A watershed is the land base surrounding and draining downhill into a particular river or stream . Maroon Bells watershed above Aspen, Colorado.
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The Temperate Deciduous Forest Biome Robinson Forest, Eastern Kentucky
Ecological importance of forests • Forests are WATERSHEDS: • A watershed is the land base surrounding and draining downhill into a particular river or stream Maroon Bells watershed above Aspen, Colorado
Forested Watersheds • They absorb, hold, and gradually release H2O to agricultural and urban areas downstream • Forested watersheds control erosion to reduce sediment in streams and lakes, and reduce flooding Daniel Boone National Forest, KY
Forests Regulate Climate • Up to 80% (tropical forests) of moisture in air is from evaporation and transpiration of moisture from trees • local - wet and cool around trees where otherwise hot and dry • without trees, rain causes soil erosion and fertility drops • global - forests absorb solar radiation near equator • cut trees --> radiation + heat reflected --> • changes wind, precipitation, and temperature worldwide • general - trees absorb CO2, add O2, cleansing air • cutting and burning tree releases CO2 into air, and CO2 is lost from exposed soil - no tree to absorb that CO2
Forests as filters • Trees absorb noise • Trees filter out pollution (as gasses are exchanged) • Forests help us clear our minds: • provide solitude, beauty, and nourish human spirit
Forests provide biodiversity • Forests contain a greater diversity of wildlife than any other terrestrial biome • How diverse are the forests of eastern Kentucky compared to the rest of the U.S. and other parts of the world?
What is the $$ value of a tree? • Economists (e.g., timber company) - engage in cost-benefit analysis to determine if money can be made on lumber and paper • An average tree in the eastern US might be worth about $750 for its wood products value • The costs to produce the products involve • Purchasing the standing timber • Harvest costs • Transportation costs • Processing costs • Marketing and delivery costs
What’s a tree worth ALIVE? • If you could take all the goods and services produced by ONE average tree over 50 years: • $ 31, 250 of O2 • $ 62, 500 in pollution reduction • $ 31, 250 in soil fertility • $ 37, 500 in water recycling and humidity control • $ 31, 250 in wildlife habitat • $ 2,500 in protein • Total = $196,250
Real costs tree harvest? • We justify forest practices on a SHORT TERM basis without considering value of ecological benefits that support other economic activities and help sustain the biosphere • We allow timber companies to cut our trees without collecting for nearly $200,000 in benefits that tree might otherwise provide so that they can make $750. • Need to consider the external costs (lost benefits)
The timber industry • Hardwoods • mostly deciduous; oaks, hickories, cherry • furniture, flooring, cabinets • The native, “climax” species in eastern Kentucky • Softwoods • mostly evergreen, conifers; pines, firs, spruce • paper, construction timber, plywood • High volume needed • Fast growing • High economic gain
What constitutes a forest? • CLOSED FOREST - closed canopy • 62 % of forests • OPEN FOREST – “WOODLANDS” • abundant trees but canopy not closed • Remaining 38% • Broadleaf forest = ~ 2/3 of world’s forests • Coniferous forest = ~ 1/3
Secondary vs. Old Growth • SECONDARY FORESTS - resulting from secondary ecological succession after: • logging • clearing for agriculture and abandoned • Mining • OLD GROWTH - uncut, virgin forest, resulting in: • massive trees • hundreds to thousands of years old • e.g., Douglas fir live to about 250 years old • Hemlock, Giant Sequoia, Coastal Redwoods live to 1,000’s of years old • Pine in Southeastern US – live to only 80 years old • Thousands of years old
Coastal redwood in California Yellow Birch in Michigan • Tree trunk in Blanton Forest in southeastern Kentucky Giant Sequoias in California
Old Growth Forests provide - greater diversity of plants - greater diversity of animals • tree cavities!! • Wood ducks, squirrels, raccoons, • food production • Acorn production is much higher in older trees. • Food production for wildlife is generally greater in old growth
Forest Edge – good or bad? • EDGE habitat in treefall gap vs. man-made • forest management of commercially important trees - most are shade-intolerant (need clear open area to grow) • shade tolerant - typically the “climax” species - KY = CHESTNUT, OAK, POPULAR - Lilly Cornett Woods - Letcher Co. near Whitesburg
Only you can appreciate forest fires • Fires • Smokey the Bear!! • once thought harmful • rapid regeneration after fire • can remove competitors and return nutrients to soil, leaving large, fire - resistant species • can remove litter fungi • Giant Sequoia needs geminate only after fire ( or after intense heat!!) • Surface fire - litter and undergrowth only • Crown fires - hot, usually where fires have bow prevented (i.e. lots of dead wood in tree tops)
Prescribed fire • Prescribed burning - to do natures work on man’s schedule • Get different results depending on • Time of year • Time of day • Moisture content of air • Geographic location • Species composition
Diseases of forests • DISEASES - in healthy, diverse forests, disease rarely get out of hand • resistant species / genotypes • CHESTNUT BLIGHT: CHINA - almost all • DUTCH ELM DISEASE: ASIA and EUROPE - 2/3 killed • WHITE - PINE BLISTER RUST: EUROPE • constant problem; esp. in monocultures
Impacts of insects on forests • birds, etc. usually control insects • bark beetle in S. and W. U.S. pine / spruce • Spruce budworm - defoliate • Gypsy moth • Aphids - suck sap (wooly aphid) and scale insect