Presentation Transcript
Chapter 13: Chapter 13 Forests, Parks and Landscapes
The Landscape Concept: The Landscape Concept Landscaper Perspective
The concept that effective management and conservation recognizes that ecosystems, populations and species are interconnected across large geographic areas
Modern Conflicts over Forest Land and Forest Resources: Modern Conflicts over Forest Land and Forest Resources Silviculture: the the professional growing of trees
Forests benefit people through public service functions: functions performed by ecosystems for the betterment of life and human existence
Ex) cleansing of air by trees
The Life of a Tree: The Life of a Tree How a Tree Grows
Photosynthesis, Transportation Systems, Evapotranspiration
Tree Niches
Determined by
Water content in the soil
Forest tolerance of shade
There is no single best set of conditions for a forest
A Forester’s View of a Forest: A Forester’s View of a Forest Old-Growth Forest: a forest that has never been cut
Second-Growth Forest: has been cut and re-grown
Foresters group trees into:
- Dominants, Codominants, Intermediate and Suppressed
Sites are classified by site quality: the maximum timber crop the site can produce in a given time
Clear-Cutting: Clear-Cutting The cutting of all trees in a stand at the same time
Controlled cutting 4 types:
Shelterwood-Cutting
Seed-Tree Cutting
Selective Cutting (thinning)
Strip-Cutting
Plantation Forestry: Plantation Forestry Plantation: a stand of single species planted in straight rows
Currently provide a large percentage of wood use – and growing
Properly managed plantations can relieve pressure on forests
Sustainable Forest: Sustainable Forest Def: Efforts to manage a forest so that a resource in it can be harvested at a rate that does not decrease the ability of the forest ecosystem to continue to provide that same rate of harvest indefinitely.
There are few examples of this. The “certification of sustainable forestry” developed. This involves:
Determining which methods appear most consistent with sustainability
Comparing the management of a specific forest with those standards
4 Ways Vegetation Can Effect the Atmosphere:: 4 Ways Vegetation Can Effect the Atmosphere: Changing color of the surface and the amount of sunlight reflected and absorbed
Increasing the amount of water transpired and evaporated from the surface to the atmosphere
Changing the rate at which greenhouse gases are released from the Earth’s surface into the atmosphere
Changing the “surface roughness,” which affects wind speed at the surface
Deforestation: Deforestation History – dates back to Roman and Greek times. In modern times S. America is biggest loser
Causes:1) clearing land for agriculture and ranching 2) sale of timber
World Firewood Shortage- 63% of wood produced is used as firewood. Major energy source in sub-Sahara Africa,Central America,, S.E. Asia
Indirect Deforestation- air pollution mainly acid rain; disease; bug infestation; Global Warming?
Parks, Nature and Wilderness: Parks, Nature and Wilderness Wilderness: an area undisturbed by people. No development permitted
Managing parks for biological conservation is a relatively new idea. Parks that are too small or in the wrong shape may not be able to sustain their species
Administration of Federal Lands: Administration of Federal Lands Bureau of Land Management –Interior
US Forest Service – Agriculture
US Fish & Wildlife Service – Interior
National Park Service – Interior
Other:- Dept of Defense, Bureau of Land Management
Major US Lands: Major US Lands