Slide 1

Chapter 10: Land, Public and PrivateChapter 8: Soil1Julia ButterflyAnswer 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 Maxxam clearcut 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 LandsNational 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.

Public Lands

RangelandsDry, open grasslands that are primarily used for cattle grazing. (compare to CAFOs ~ FOOD, Inc.)

ForestsAreas dominated by trees and other woody vegetation.

Timber Harvest PracticesClear-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 Managementprescribed burns- a fire is deliberately set under controlled conditions.

ForestsNational Parks- established to preserve scenic views and unusual landforms.National wildlife refuges- managed for the purpose of protecting wildlifeNational wilderness areas- set aside to preserve large tracts of intact ecosystems or landscapes.Federal RegulationsNational 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 anenvironmental 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.12

Soil is important because itIs a medium for plant growthBreaks down organic material and recycles nutrientsServes as a filter for water and removes pollutantsA habitat for living organismsSoilFactors that determine the formation of soil:Parent material- what the soil is made from influences soil formationClimate- what type of climate influences soil formationTopography- the surface and slope can influence soil formationOrganisms- plants and animals can have an effect on soil formationTime- the amount of time a soil has spent developing can determine soil properties. The Formation of SoilParent Material- the rock material from which soil is derived.

The Formation of Soil

As soils form, they develop characteristics layers. 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.Soil Horizons

Same information as last slide, but a more detailed lookSoil Horizons

Humus- dark, soft, spongy residue of organic matter as a result of decomposition of organic matter such as leaves and dead wood1 source of nutrients in soil systems

O HorizonSoil Horizons

A HorizonTop soil-mixture of humus and leachable mineral soilThin roots extend into this layer

Soil Horizons

E HorizonEluviation process of leachingMinerals are leached into this layer from H2O movement downward

Soil Horizons

B HorizonSubsoilOften high in iron, aluminum, and calciumOften high in clay content

Soil Horizons

C HorizonWeathered parent materialGlacial deposits, volcanic ashReveals history of the landClasses of SoilMollisols- very fertile, dark, found in temperate grasslands, best agricultural soil, Deep A horizonOxisols- soil of tropical and subtropical rainforest layer of iron and Al oxides in B horizon, little O horizonAlfisols- weathered forest soil, not deep, but developed OAE+B typical of most temperate forest biome. Need fertilizer for agricultureAridsols- dry lands + desert, lack of vegetation, lack of rain unstructured vertically, irrigation leads to salinization b/c of high evaporation.Texture: the percentage of sand, silt and clay the soil contains.Physical Properties of Soil

Loam is theoretically the ideal soil40% sand 40% silt 20% clay

Porosity- how quickly the soil drains (which depends on its texture)

Physical Properties of Soil

Chemical Properties of SoilCation 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

27Biological Properties of SoilMany organisms are found in the soil including fungi, bacteria, protozoans, rodents and earthworms. 27

Microbes in TopsoilBacteriaA 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 | eHow http://www.ehow.com/list_5979001_microbes-topsoil.html#ixzz2W1KxByvsMicrobes in TopsoilFungiFungi 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 | eHow http://www.ehow.com/list_5979001_microbes-topsoil.html#ixzz2W1KxByvsBeneficial fungi, such as mycorrhizae, improves plant health by forming a helpful relationship with plant roots. Harmful fungi such as verticillium, pythium and rhizoctonia may do the opposite and destroy plant roots. Microbes in TopsoilProtozoaProtozoa 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 | eHow http://www.ehow.com/list_5979001_microbes-topsoil.html#ixzz2W1KxByvsActs & LawsPublic Policy and SoilLow Input sustainable Agriculture (LISA)-started by US Defense of Agriculture in 1988 Conservation Reserve Program- 1985Food Security Act of 1985Federal Agriculture Improvement and Reform (FAIR) 1996Environmental Quality Incentive Program (EQUIP)*Agriculture & Farming Research Initiative (AFRI)