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Chapter 10: Land , Public and Private Chapter 8: Soil. Julia Butterfly. Answer the following questions (in your journals) by reading the article about Julia Butterfly on page 261: 1. What is the difference between clear-cutting and selective-cutting?
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Chapter 10: Land, Public and Private Chapter 8: Soil
Julia Butterfly • Answer the following questions (in your journals) by reading the article about Julia Butterfly on page 261: • 1. What is the difference between clear-cutting and selective-cutting? • 2. What happened when Maxxamclearcut redwood forests? • 3. How can a “tree sit” prevent widespread deforestation? • 4. What did Maxxam ultimately resolve to do? • 5. Do citizens of the United States have the right to influence what activities occur on private lands? What if the land is public? • 6. Was Julia Butterfly Hill a hero or a villain?
Public Lands • National Parks- managed for scientific, educational, and recreational use, and sometimes for their beauty or unique landforms. • Managed Resource Protected Areas- managed for the sustained use of biological, mineral, and recreational resources. • Habitat/Species Management Areas- actively managed to maintain biological communities. • Strict Nature Reserves and Wilderness Areas- established to protect species and ecosystems. • Protected Landscapes and Seascapes- nondestructive use of natural resources while allowing for tourism and recreation. • National Monuments- set aside to protect unique sites of special natural or cultural interests.
Rangelands • Dry, open grasslands that are primarily used for cattle grazing.(compare to CAFOs ~ FOOD, Inc.)
Forests • Areas dominated by trees and other woody vegetation.
Timber Harvest Practices • Clear-cutting- removing all, or almost all the trees in an area. • Selective cutting- removing single trees or relatively small numbers of trees from a forest.
Fire Management • prescribed burns- a fire is deliberately set under controlled conditions.
Forests • National Parks- established to preserve scenic views and unusual landforms. • National wildlife refuges- managed for the purpose of protecting wildlife • National wilderness areas- set aside to preserve large tracts of intact ecosystems or landscapes.
Federal Regulations • National Environmental Policy Act (NEPA)- mandates an environmental assessment of all projects involving federal money or permits. • 1969 requires all agencies responsible for a major federal project to file an environmental impact statement-The best way the protect endangered and threatened species is by protecting the habitat. • Environmental Impact Statement(EIS)- outlines the scope and purpose of the project. • Environmental mitigation plan- outlines how the developer will address concerns raised by the projects impact on the environment.
Erosion • Erosion: the physical removal of rock fragments from a landscape or ecosystem. Wind, water, ice transport and living organisms can erode materials. • Deposition: the accumulation or depositing of eroded material such as sediment, rock fragments or soil.
Soil Soil is important because it • Is a medium for plant growth • Breaks down organic material and recycles nutrients • Serves as a filter for water and removes pollutants • A habitat for living organisms
The Formation of Soil Factors that determine the formation of soil: • Parent material- what the soil is made from influences soil formation • Climate- what type of climate influences soil formation • Topography- the surface and slope can influence soil formation • Organisms- plants and animals can have an effect on soil formation • Time- the amount of time a soil has spent developing can determine soil properties.
The Formation of Soil • Parent Material- the rock material from which soil is derived.
Soil Horizons O horizon- (organic layer) composed of the leaves, needles, twigs and animal bodies on the surface. A horizon- (topsoil) the zone of organic material and minerals mixed together. B horizon- (subsoil) composed primarily of mineral material with very little organic matter C horizon- (parent material) the least weathered horizon and is similar to the parent material. As soils form, they develop characteristics layers.
Soil Horizons Same information as last slide, but a more detailed look…
Soil Horizons OHorizon • Humus- dark, soft, spongy residue of organic matter as a result of decomposition of organic matter such as leaves and dead wood • 1۫ source of nutrients in soil systems
Soil Horizons AHorizon • Top soil-mixture of humus and leachable mineral soil • Thin roots extend into this layer
Soil Horizons EHorizon • Eluviation process of leaching • Minerals are “leached into this layer from H2O movement downward
Soil Horizons BHorizon • Subsoil • Often high in iron, aluminum, and calcium • Often high in clay content
Soil Horizons • Weathered parent material • Glacial deposits, volcanic ash • Reveals history of the land CHorizon
Classes of Soil Mollisols- very fertile, dark, found in temperate grasslands, best agricultural soil, Deep A horizon Oxisols- soil of tropical and subtropical rainforest layer of iron and Al oxides in B horizon, little O horizon Alfisols- weathered forest soil, not deep, but developed OAE+B typical of most temperate forest biome. Need fertilizer for agriculture Aridsols- dry lands + desert, lack of vegetation, lack of rain unstructured vertically, irrigation leads to salinization b/c of high evaporation.
Physical Properties of Soil Texture: the percentage of sand, silt and clay the soil contains.
Loam is theoretically the ideal soil40% sand 40% silt 20% clay
Physical Properties of Soil • Porosity- how quickly the soil drains (which depends on its texture)
Chemical Properties of Soil Cation exchange capacity- the ability of a soil to adsorb and release cations, positively charged mineral ions. Soil bases- calcium, magnesium, potassium and sodium Soil Acids- aluminum and hydrogen Base saturation- the proportion of soil bases to soil acids
Biological Properties of Soil Many organisms are found in the soil including fungi, bacteria, protozoans, rodents and earthworms. 27
Microbes in Topsoil Bacteria • A teaspoon of topsoil can contain 100,000 to 1 million bacteria. • Rhizobia is quite common; it aids in a plant's uptake of nitrogen, and is particularly helpful for vegetable and legume plants. • Bacteria are helpful in many other areas, such as decomposing soil materials, improving soil structure and degrading any topsoil pollutants. Microbes in Topsoil | eHowhttp://www.ehow.com/list_5979001_microbes-topsoil.html#ixzz2W1KxByvs
Microbes in Topsoil Fungi • Fungi can be either beneficial or harmful to soil. • The number of fungi in 1g of soil can range from 100,000 to 1 million. Microbes in Topsoil | eHowhttp://www.ehow.com/list_5979001_microbes-topsoil.html#ixzz2W1KxByvs
Microbes in Topsoil Protozoa • Protozoa are larger than bacteria, and feed on fungi, bacteria and other protozoa. • The three types of protozoa are ciliates, amoebae and flagellates. • Protozoa thrive in moisture, and tend to live near plant roots. They are responsible for increasing soil nutrients and regulating the number of bacteria in soil. Microbes in Topsoil | eHowhttp://www.ehow.com/list_5979001_microbes-topsoil.html#ixzz2W1KxByvs
Acts & LawsPublic Policy and Soil Low Input sustainable Agriculture (LISA) -started by US Defense of Agriculture in 1988 Conservation Reserve Program- 1985 Food Security Act of 1985 Federal Agriculture Improvement and Reform (FAIR) 1996 Environmental Quality Incentive Program (EQUIP) *Agriculture & Farming Research Initiative (AFRI)