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Chapter 14: Soils & Environment

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Title: Chapter 14: Soils & Environment


1
Chapter 14 Soils Environment
2
soil composition
  • organics
  • air
  • water
  • weathered earth materials (parent material)
  • mechanical weathering
  • smaller, rounder pieces (if moved)
  • chemical weathering
  • feldspars and water clays
  • calcite - dissolves
  • organics - dissolve - acidify water
  • quartz - usually left behind
  • transported vs residual

3
formation
  • dominated by downward movement of water
  • weathers parent material
  • moves dissolved substances downward

4
Soil profile - fig p 440
  • created by downward movement of water
  • horizons
  • O - organic humus little or no parent material
  • A
  • weathered parent material w/ organics
  • zone of leaching
  • E - few organics or iron
  • B - zone of accumulation
  • Bt - clay enriched
  • Bk - calcium enriched - calcium coats
  • K
  • calcium dominated
  • caliche - calcium layers
  • C - partially altered parent material
  • R - parent material

5
soil properties
  • color
  • related to composition
  • organics - dark yellow
  • iron - red or grey - dominates
  • calcium - light or white
  • describe wet - use charts
  • texture
  • grain size distribution (among fraction lt2mm
  • estimate in field - measure in lab
  • structure
  • peds
  • granular, blocky, prismatic, platy gtclay

6
Soil fertility
  • nutrients available for plants
  • natural
  • parent material - flood deposits, till, bedrock
  • organics
  • climate
  • temp
  • precip
  • rain supports vegitation
  • leaches nutrients
  • Northern IL forests vs rainforests
  • humans
  • alter veg
  • add and remove nutrients
  • single crops
  • crop rotation
  • erosion
  • pesticides

7
Water in soil
  • saturated vs moist vs dry
  • What effect does soil moisture have on soil
    cohesion?
  • sand (moist vs wet vs dry
  • clay (wet vs dry
  • flow
  • saturated - hi pressure to lo pressure
  • unsaturated - film of water attached to grains

8
Soil classification
  • taxonomy - based on physical and chemical props
    of soil
  • morphology
  • nutrients
  • organics
  • classification methods
  • order, suborder, great group, subgroup, family,
    series
  • focus on ag use
  • universal soil classification
  • focus on size and composition
  • used by engineers

9
What are the engineering properties of soils?
  • How will soil affect building
  • based on particle size, compostion, water content
  • behavior based on water content
  • solid/plastic/liquid
  • plastic limit, liquid limit - diff is plasticity
    index
  • take soil, add water until ribbons form, flows
  • wet weight - dry weight over dry weight
  • strength - how well does soil hold together and
    support
  • cohesion of particles - esp for fine grain
  • molecular and electrostatic forces
  • moisture
  • friction - density, size, and shape of particles
    - esp for coarse grain
  • vegetation
  • sensitivity
  • change in strength as a result of disturbance
  • coarse - low
  • fine - high esp clay
  • compressibility
  • coarse - low

10
Land use and soils
  • What are the causes and effects of soil erosion?
  • landscape modification
  • resulting in increased erosion, esp during
    modification
  • urbanization
  • sharp sed load increase followed by long term
    decrease
  • timber harvests
  • removes cover and roots
  • clear cut vs select cut
  • equipment disturbance
  • agriculture - tilling and grazing
  • exposes soil to wind and water
  • management - wind breaks, contour farming,
    no-till, terracing, strip cropping, CRP, buffer
    zones
  • other effects
  • chemical pollution - fertilizer, pesticides,
    herbicides
  • nutrient loss
  • off-road vehicles
  • mechanical - motorcycles, 4wd, mountain bikes
  • animal - horses, hikers
  • Sediment pollution

11
Soil pollution
  • addition of toxic or carcinogenic substances to
    soil
  • factors
  • mobility
  • solubility
  • attraction to clays
  • decompostion
  • chemical (agrichems
  • biological
  • presence of
  • oxygen
  • water
  • microorganisms

12
What is desertification?
  • conversion of productive land to desert
  • factors
  • deforestation
  • soil erosion
  • poor drainage of irrigated land
  • overdraft of water
  • accelerated by drought stress
  • affects long term hydrologic cycle - climate
  • North American example
  • water tables
  • salinization of soil and near-surface soil water
    from irrigation
  • reduction of surface water in streams and lakes
  • high rates of soil erosion
  • loss of native vegetation
  • interrelated factors - salinization - veg loss -
    erosion
  • patchy occurrences

13
Soil surveys and land use planning
  • soil maps
  • soil cross-sections
  • soil descriptions
  • inc grain size distribution
  • moisture content
  • strength
  • may rate soils
  • agriculture, prime, important etc
  • housing
  • industry
  • forestry
  • hydric
  • derivitive maps
  • based on specific characteristics
  • building limits, slope, thickness, moisture
    content
  • none-slight
  • moderate
  • severe

14
Chapter 16 Global Climate Change
15
Global change
  • Earth has been changing since beginning early
    preCambrian (over 4.5 billion years)
  • Scale of variability - days to gt10,000's yrs
  • Causes of variability
  • Sun - output, angle
  • Earth
  • rotation speed (slowing)
  • continental movements
  • Volcanic output
  • Life - O2 CO2 cycles, humans

16
Research priorities
  • is there change?
  • on what scale?
  • what are the causes?
  • what are the affects?

17
Composition of atmosphere
  • N - 78
  • O2 - 21
  • Ar 0.9
  • CO2 0.03
  • other 0.07 CH4, 3, CO, NOx, SOx, H2S, etc
  • water 0 to 4

18
Energy balance
  • almost all energy ultimately from sun
  • earths energy cycle
  • reflects 30
  • absorbs 70 (visible IR)
  • emits IR (as much energy as it receives)

19
Earths temperature based on
  • sunlight received
  • amount reflected
  • atmospheric retention greenhouse effect
  • H2O vapor, CO2, CH4, CFCs
  • natural process
  • increasing in atmos due to humans
  • CO2 changes
  • highs - interglacial periods - 125K yrs ago and
    now
  • current increase started in 1800's
  • releasing stored CO2 from rx
  • other changes

20
Tools to study global change
  • Geologic record
  • Real time
  • Mathematical modeling - global circulation models

21
Earths Climate
  • on average warmer than present
  • current
  • ice age - 2MYA to present
  • last glacial advance
  • ended 10,000 yrs ago
  • gradually warming since
  • anthropogenic effects

22
Potential Effects of Global Warming
  • climate change
  • more rain
  • more violent storms
  • sea level rise
  • complex responses (unpredictable)

23
Chapter 17Geology, Society, and the Future
Selected Examples
24
Geology may influence diseases and death rates
  • acute vs chronic response
  • Element requirements for life
  • Metals - H, Na, Mg, K, Ca
  • Non-metals - C, N, O, P, S, Cl, Fe - hemoglobin
  • Trace - Fluorine, Cr, Mn, Cobalt, Cu, Zn,
    Selenium, Molybdenum, Iodine

25
Concepts of waste management
  • dilute and disperse
  • concentrate and contain
  • integrated waste management

26
integrated waste management
  • resource recovery
  • goal zero waste production
  • recycle
  • reuse
  • reduce - pay as you throw
  • move waste around
  • sequential land use (subsequent uses must be
    limited)
  • front end controls
  • more efficient processes
  • less packaging

27
waste stream
  • Waste types
  • industrial
  • construction
  • demolition
  • municipal
  • commercial
  • medical
  • Composition
  • paper
  • hard waste
  • plastics
  • metals
  • food
  • glass
  • wood

28
Disposal methods
  • on site - any method
  • sewer (note on-site in book
  • incineration
  • produces ash and air waste
  • composting recycles organic waste
  • landfill - engineered site

29
Landfills
  • considerations
  • leachate
  • methane
  • rodents pests
  • active face - blowing trash
  • site selection
  • local approval
  • IL PCB - legal requirements
  • IL EPA - engineering requirements

30
Landfills
  • site design - fig p 544
  • geology
  • liners
  • leachate collection and treatment
  • waste types accepted
  • monitoring
  • landfill conditions
  • migration routes
  • cells
  • subsequent monitoring and design

31
Hazardous Chemical Waste
  • waste byproducts
  • uncontrolled sites - CERCLA
  • controlled sites - RCRA
  • responsible management
  • cradle to grave
  • generators
  • transporters
  • storage
  • treatment
  • disposal

32
Environmental Impact Statement
  • EIS summary
  • purpose and need
  • rigorous comparison of alternatives
  • description of environment
  • discussion of consequences
  • identification of issues and alternatives
  • record of decision
  • alternatives
  • which are preferred
  • rationale
  • avoidance and/or mitigation required

33
Site selection and evaluation
  • physiographic determinism
  • design with nature
  • minimize landscape alteration
  • focus - will site provide needs of use
  • process - fig p 555
  • collect data
  • recon likely sites
  • collect addnt data
  • magnitude and importance of geologic limitations
    and possibilities

34
Methods of site selection and evaluation
  • cost benefits analysis
  • physiographic determinism
  • use map overlays (to show s and -s)
  • choose best site
  • use physical, social, aesthetic, etc
  • Environmental geology mapping
  • interpretive
  • may focus on anticipated uses
  • content based on user
  • GIS

35
considerations of site selection and evaluation
  • Landscape aesthetics - scenic resources
  • hard to evaluate - subjective
  • uniqueness - overall scenic
  • sequential land use - fig p 556
  • multiple land use - fig p 557

36
Environmental Law Basis
  • Trust doctrine
  • each generation has a moral responsibility to
    provide the next with healthful, productive and
    aesthetically pleasing surroundings
  • Declaration of Independence
  • Government protects each persons right to life,
    liberty, and the pursuit of happiness

37
Environmental Law Basis
  • Constitution
  • Preamble - promote the general welfare, and
    secure the blessings of liberty to ourselves and
    our posterity
  • Article 1, section 8 (Congressional powers)
  • to regulate commerce among the several states
  • toprovide for the common defense and general
    welfare of the US

38
Environmental Law Basis
  • Constitution
  • 9th amendment
  • The enumeration in the Constitution, of certain
    rights, shall not be construed to deny or
    disparage others retained by the people
  • 5th amendment
  • No person shall bedeprived of life, liberty, or
    property without due process of law nor shall
    private property be taken for public use without
    just compensation
  • 10th amendment
  • The powers not delegated to the US by the
    constitution, nor prohibited by it to the states
    are reserved to the states respectively, or to
    the people
  • 14th amendment, section 1
  • extends 5th amend to states

39
Environmental Legislation Federal
  • Refuse act of 1899 - unlawful to discharge refuse
    into tributaries of navigable waters Permit from
    Sec of Army
  • National Environmental Policy Act
  • focused attn on potential env degradation
  • provided a framework for proj eval (EIS
  • increased efforts to protect env in US
  • Clean Water Act Clean Air Act
  • CERCLA RCRA

40
Environmental Law local
  • land use planning and law
  • zoning

41
Environmental Law controversies
  • highest and best use
  • most profitable use
  • takings
  • conflict with treaties and trade agreements

42
Environmental Law International
  • Law of the seabed
  • up for grabs
  • no treaties
  • 20 mile limit
  • treaties
  • trade agreements
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