Chapter 14 Soil Resources

Soil  Uppermost layer of Earth’s crust that supports plants, animals and microbes  Soil Forming Factors  Parent Material  Time  Climate  Organisms  Topography

Soil Composition  (45%) ________ __________ ___________  (5%) _________ _______________  (25%) _________

Soil Organisms  Soil organisms provide ecosystem services

Nutrient Cycling

Soil Properties

Soil Problems  1. ___________________  Caused primarily by water and wind  Why a problem?  Causes a loss in soil fertility as organic material and nutrients are eroded  More fertilizers must be used to replace nutrients lost to erosion  Accelerated by poor soil management practices

The Dust Bowl

Soil Problems  2. _________________________

 Suppress plant diseases and pests.  Reduce or eliminate the need for chemical fertilizers.  Promote higher yields of agricultural crops.  Facilitate reforestation, wetlands restoration, and habitat revitalization efforts by amending contaminated, compacted, and marginal soils.  Cost-effectively remediate soils contaminated by hazardous waste.  Remove solids, oil, grease, and heavy metals from stormwater runoff.  Capture and destroy 99.6 percent of industrial volatile organic chemicals (VOCs) in contaminated air.  Provide cost savings of at least 50 percent over conventional soil, water, and air pollution remediation technologies, where applicable.

 _______________ _______________ Soil Problems  3. Soil Salinization  Gradual accumulation of salt in the soil, usually due to improper irrigation techniques

Soil Problems   4. Desertification   _____________________________________ _____________________________________

Desertification Around the World   Desertification now threatens vast areas   Africa   China   The best way to avoid desertification:   _____________________________________ _____________________________________

Modern Dust Clouds

 2. Crop Rotation  ______________________________________ ______________________________________ Soil Conservation  1. ________________  Residues from previous year’s crops are left in place to prevent soil erosion

Strip Cropping Soil Conservation  3. Contour Plowing  ___________________________________  Strip Cropping- ______________________________________ _____________________________________ ______________________________________ _____________________________________  4. ______________  ______________________________________ ______________________________________ Terracing

Preserving Soil Fertility  Organic fertilizers  __________________ __________________ _________________  __________________ __________________ __________________ __________________ __________________  Inorganic fertilizers  _________________________ _________________________  Soluble  ________________________  _________________________ _________________________  Problems:  _____________________

Soil Reclamation  Two steps 1. Stabilize land to prevent further erosion 2. Restoring soil to former fertility  Best way to do this is shelterbelts  Row of trees to reduce wind erosion

Soil Conservation Policies in US  Soil Conservation Act 1935  Food Security Act (Farm Bill) 1985

Sustainable Use of Biological Wealth   Excluding cattle from riparian zones   Flood protection   Water conservation   Habitat for wildlife   Preservation of biodiversity

Riparian Restoration   San Pedro River before and after restoration