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Island Biogeography. First proposed by E.O. Wilson & Robert MacArthur in the 1960s. Now is a fundamental concept in conservation techniques. “Island” is any area of suitable habitat surrounded by an area of unsuitable habitat Must consider these when designing protected areas: Size Shape
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Island Biogeography • First proposed by E.O. Wilson & Robert MacArthur in the 1960s. • Now is a fundamental concept in conservation techniques. • “Island” is any area of suitable habitat surrounded by an area of unsuitable habitat • Must consider these when designing protected areas: • Size • Shape • Proximity to humans & other disturbances • Corridors • Amount of edge
One More… Which is better (black or white? Why? SLOSS
Forest Ecosystem Services • What do you think? • Supply materials for humans • Fuel, timber, paper products • Medicines, Foods • Moderation of local climate (transpiration) • Biogeochemical Cycles • Erosion control • Watersheds • Animal habitat
Managed Forests • Most are monocultures • Planted in rows • Same size, same age trees • Prone to insects/diseases • Insecticides, fungicide use is common • Simpler ecosystem due to the monoculture in trophic level 1
Harvesting Trees • 5 countries have the most trees… • US, Canada, Russia, China, Brazil • 55% of the trees are burned • (fuel wood or charcoal) • 45% used for paper / wood products • In highly developed nations!! Methods of Harvesting Trees • Seed Tree Cutting • Clearcutting • Selective Cutting • Shelterwood Cutting
Harvesting Methods - Selective Cutting • Cut a few mature trees individually or in small clusters. Rest of the forest is intact.
Harvesting Methods - Shelterwood Cutting • Some mature trees are harvested. Remaining trees provide protection/shade for younger trees to regenerate. Logging continues as those grow up.
Harvesting Methods - Seed Tree Cutting • Nearly all trees are harvested, leaving a few desirable trees to provide seeds for regeneration.
Harvesting Methods - Clearcutting • Removal of all trees. Area is reseeded or replanted.
Discussion: Compare/Contrast the 4 methods • Which is most desirable for Loggers? For natural species? • Would all species be impacted the same by a certain method? Why/Why not? • What are the PROS & CONS of each? (environmentally and economically) • Would TREE AGE & TREE TYPE impact which method you choose? • Would the product being created impact which method you choose?
Deforestation • World decrease of 37 million acres yearly • Causes: • Drought, land clearing, expansion of agriculture, road construction, tree harvesting, insects, disease • How does this impact soil? • How does this impact waterways? • How does this impact groundwater? • How does this impact species? • How does this impact climate? (temperature, moisture)
US Forest Conservation – Forest Legacy Program • For privately owned lands • Landowner & government agency/conservation organization enter into a “conservation easement” agreement • Landowner sells land to the government or a conservation organization with understanding that it will be protected from development for a certain number of years. • Type of easement (permanent or for X number of years) varies • Land remains in private ownership.
Wetlands & Coastlines – Ecosystem Services Name some from the cartoon. • Groundwater recharge • Reduce flooding • Improve water quality (filtration) • Habitat • Products (food, etc) • Recreation
Wetlands & Coastline Threats • Threats • Drainage for pest control • Dredging for navigation • Dam construction • Dykes for flood control • Use for waste dumping • Development (buildings) • Aquaculture use • Protection • Wetland Reserve Program • All about education! • All about ownership! • Marine Sanctuaries are commonly: • Coral reefs • Kelp beds • Shipwrecks …..Why????? • Managed for multiple uses
Interesting agricultural methods Vegetation can minimize odor movement Shelterbelts – minimize wind erosion