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A Closer Look and Water and Soil Degradation Part III


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Title: A Closer Look and Water and Soil Degradation Part III

A Closer Look and Water and Soil DegradationPart
Soil Erosion Facts
  • Soil is a potentially renewable resource a
    resource that can be renewed in days to several
    decades, but when the resource is used faster
    than it is replenished it becomes a non-renewable
  • 1992 Study by the World Resource Institute found
  • 15 of global lands are too eroded to grow crops
    on due to overgrazing, deforestation, and
    unsustainable farming practices.
  • 2/3 of these lands exist in Africa and Asia.
  • 40 of the worlds lands (75 in Central America)
    used for agriculture are seriously degraded by
    erosion, salt build-up, and waterlogging.
  • Soil erosion has reduced food production on 16
    of the worlds arable (crop) lands.
  • Worldwide soil erosion causes at least 375
    billion per year (42 million per hour!) in
  • 1. direct damage to agricultural lands
  • 2. indirect damage to waterways,
    infrastructure, and human health.
  • Soil erosion cost 30 billion dollars in 1997
    (3.4 million per hour!)
  • Desertification causes plant productivity to fall
    by 10 each year (a process whereby arid and
    semiarid lands change to desert-like conditions
    due to human activities and climate changes).

Agents of Erosion
  • Wind
  • Water
  • Ice
  • Gravity
  • (mass wasting)

Types of Soil Erosion
  • 1. Sheet Erosion occurs when surface water
    flows down hill and peels off top soil in a
    sheet-like pattern.
  • 2. Rill Erosion is from fast moving surface
    water that gouges out rivulets that cut small
    channels into the soil.
  • 3. Gully Erosion when rivulets join together
    to make a larger gully.

Sheet erosion
Gully Erosion
Dust Bowl
Causes of the Dust Bowl
  1. Poor cultivation practices on fertile, arable
    lands where plowing tore up the roots of native
    prairie grasses (extensive root systems) which
    were replaced by agricultural crops (less
    extensive root systems).
  2. After each harvest, the land was plowed and left
    bare for several months, exposing it to high

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Causes of the Dust Bowl
  1. Overgrazing destroyed large expanses of grass,
    denuding the ground.
  2. Drought occurred between 1926 and 1934.

Journalists Name the Dirty Thirties the Dust
  • During May, 1934, a cloud of topsoil blown off
    the Great Plains (1,500 miles away) blanketed
    most of the eastern United States (Washington
    D.C. and New York City).
  • The same day, Hugh Bennett of the U.S. Department
    of Agriculture (USDA) was in Washington as the
    dust arrived pleading for new programs to protect
    the countrys topsoil and farmers.

Washington D.C./Hugh Bennett
Did We Learn Our Lesson From the Dust Bowl?
  • 1935 USA passed the Soil Conservation Act which
    established the Soil Conservation Service (SCS),
    now called the Natural Resources Conservation
    Service (NRCS), and began promoting sound
    conservation practices, initially in the Great
    Plains States and then in each County in every
    state! Soil Surveys were developed.
  • Farmers who migrated to California began using
    the land more sustainably and invited assistance
    from USDA and Soil Conservation Service. No till
    farming was introduced where the soil is
    disturbed slightly by making slits in rows in
    which seeds are planted.

Soil Protection Regulations
  • 1973 Sediment Pollution Control Act requires
    that no land-disturbing activity during periods
    of construction or improvement to land shall be
    permitted in proximity to a lake or natural
    watercourse unless a buffer zone is provided
    along the margin of the watercourse AND the angle
    for graded slopes and fills cannot be greater
    than the angle which natural vegetation can be
    established and retained for soil anchorage
    (slope stabilization).
  • A Sediment and Erosion Control Plan MUST be
    submitted and approved by the regulatory agency
    overseeing the project.

Sediment Pollution Control Act - 1973
Coir Fiber matting
Silt Curtain
Hay Bales
Farmland Preservation Act
  • State agencies must establish agricultural land
    preservation policies and working agreements with
    the USDA.
  • The goal is to minimize farmland conversions from
    agricultural zoning to residential and
    industrial zoning.
  • For approved conversions and Utility projects,
    the USDA reviews and ensures that Plans contain
    construction and restoration standards that leave
    affected areas in good condition after projects
    are completed.

Farmland Preservation on Long Island
  • Town of Southhold Leads the Way!
  • Work with Long Island Farm Bureau, Peconic Land
    Trust, and Southold Town Farmers to Preserve
    Farmland from ever being developed.
  • If a farmer has to raise cash from his land he
    has two options 1. Subdivide the land and
    pursue a maximum-intensity subdivision at the
    current zoning (2-acre).
  • 2. Look into the benefits of the farmland
    preservation program.
  • Recent experience shows that if a farmer wants to
    build 1 or 2 houses on his farm parcel, and sell
    the development rights to the remainder of his
    land, his net return is nearly the same as a
    full-intensity subdivision.
  • The advantage of selling the development rights
    to the Land Trust is that he can continue to own
    and farm the preserved land making additional
    money AFTER fair compensation received
    (25,000/acre) for selling the development
  • This achieves the Town's preservation goals and
    has become an increasingly popular preservation
    tool, known as a Conservation Opportunity
    Subdivision (COS).

Town of Southold
  • Presently, 1 house for every 5 acres of land may
    built in the Town of Southold 2 acre zoning in
  • Over 3,500 acres of farmland have been preserved
    in Southold due to the Development Rights Program
    (begun in Suffolk County in 1974).
  • In actuality 1 house is developed for every 18
    acres preserved in Southold!
  • The Town can pay fair compensation to farms for
    transfer through a 2 Transfer Tax for real
    estate sales on all other properties in the Town!
    Fair compensation is considered to be
  • To maintain the success of the DRP and COS is to
    ensure that fair compensation remains consistent
    with full-intensity development costs.

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Farm Act - 1985
  • Farmers are given subsidies for highly erodible
  • They MUST take the land out of production for 10
  • The land may NOT be farmed, grazed of cut for hay
    OR farmer must pay back subsidy!
  • This has cut erosion by 60 in the USA since
  • Swampbusters is part of the Farm Act denies
    federal funding to farmers who drain or destroy
    wetlands on their property.

A Look at Hydroponic and Aeroponic Crop Production
  • Hydroponics based on the idea that plants will
    grow as long as they have air, water, nutrients,
    and energy, but not necessarily soil.
  • Two Types
  • a. Water culture where roots of plants are in
    water instead of soil, air is pumped in, and
    nutrients are added.
  • b. Aggregate Culture where plants are placed
    in sand, gravel, or peat which supports the plant
    and lets air get to the roots like soil does.
    Nutrients are added.

Drip Irrigation Technique
  • Aeroponics is a hydroponic technique involving
    the use of sprayers, nebulizers, foggers, or
    other devices to create a fine mist of solution
    to deliver nutrients to plant roots.

Root Mist Technique
Fog Feed Technique
Disadvantage of Hydroponic Systems
  • High cost of construction, equipment, fuel, and
    skilled workers.
  • Large-scale operations dont exist.
  • It is suitable for places where land or water is
    too scarce or too valuable to use for farming
    such as in cities (roof-top community gardens),
    not useful for large-scale operations.

Soil-less Solutions
Ground Water Resources
  • Freshwater on/below Earths surface 3
  • Saltwater 97

  • Precipitation infiltrates and percolates downward
    through soil pore spaces and rock crevices and is
    stored below ground.
  • Groundwater surplus higher than normal water
  • Groundwater deficit lower than normal water

Water Budget
Water Surplus Inputgtoutput
Average WT
Water Deficit Inputltoutput
  • Aquifer porous soils allow for water to
    accumulated in layers of sand and gravel confined
    by clay layers (confining layers)

Long Island Sole Source Aquifer
Groundwater Recharge Areas
  • Recharge Areas any area of land where water
    passes downward or laterally into an aquifer.
    Example Long Island Pine Barrens or Development
    Recharge Basins sumps.

Long Islands Groundwater Recharge
Freshwater Uses
  • Irrigation 16
  • Energy Production Cooling 25
  • Domestic/Municipal use 10
  • (mostly developed nations)
  • Agriculture and Industrial Processing 50
  • Eastern USA plenty of water
  • Western USA arid region water shortages
  • Long Island Sole Source Aquifer

Causes of Water Shortages
  • Dry Climate
  • Drought Precipitation (low), Evapotranspiration
    and evaporation (high)
  • Dessication (drying out)
  • Water stress as population increases (Las Vegas)
  • Precipitation 10cm/yr 64 water usage by
    homeowners for lawns and gardens!
  • Result water diversion from Colorado River to
    meet water consumption needs.

Water Rights in the USA
West First Come-First Serve basis -legal
rights to usage groundwater belongs to the owner
of the land above it! They can use as much as
they want, divert it or sell it to make a
profit! Garrett Hardins Tragedy of the
Commons (FBL)
  • East
  • Riparian Rights
  • -As per needed basis as long as there is enough
    water left for downstream areas.

Ogallala Aquifer
Wyoming S. Dakota Nebraska Colorado Kansas New
Mexico Oklahoma Texas
Ogallala Aquifer
  • Worlds largest aquifer
  • Water is 15,000 30,000 years old (nonrenewable)
  • VERY SLOW recharge rate
  • Used for irrigation (20) and farming (40)

Ogallala Aquifer Problems
  • Water is diverted into arid lands which are
    normally NOT arable.
  • Subsidies provided to farmers to divert water in
    an effort to decrease government crop disaster
    payments to farmers who lose their crop due to
  • The government encourages groundwater mining by
    giving tax breaks FBL
  • 3. Water experts expect the Ogallala to be
    economically depleted by 2020 at current
    consumption rate.
  • 4. Native Americans lost rights to water on what
    was originally their land due to settlers
    Appropriation Rights!

Colorado River
Colorado River Diversion
  • 1,400 miles long
  • Headwaters glacial in Colorado Rocky Mountains
  • Mouth Gulf of California, Mexico
  • Federal Energy Regulatory Commission (FERC) and
    US Army Corps of Engineers (ACE) licensed 17
    major hydropower dams and 100 minor dams.
  • Water is diverted to farmers to grow water
    thirsty crops such as alfalfa and ranchers (80)
    as far away as Californias Imperial Valley and
    to cities including Las Vegas.

Hydropower Dams Along the Colorado River
  • Water is subsidized by taxpayers for construction
    of dams.
  • This presents a false, low cost of water to
    consumers in this extremely arid region.
  • Native Americans have lost rights because of
    settlers Appropriation Rights.
  • Water allotments in USA have been exceeded,
    leaving a trickle of water for Mexicans.
  • Water quality is compromised and biodiversity

Gulf of California, Mexico
Should Water Be Privatized?
  • Pros to privitization of water when a resource
    is an investment better care is taken of the
  • Cons to privitization of water water is a
    common resource for all people to use. Is it
    fair to allow corporations to control common
  • Tragedy of the commons overuse and depletion of
    common resources.
  • Mind-set is If I dont use it, someone else
  • (Video)

Water Wars in the Middle East
Jordan River Jordan Syria Israel Tigris-Euphrate
s Turkey Syria Iraq
Nile River Ethiopia Sudan Egypt
Jordan River
Jordan River
  • Israel irrigates 2/3 of its croplands, but uses
    water more efficiently than any other country in
    the world.
  • Jordan 75 of water from Jordan River basin.
    With population on the rise, water shortages
    could cause Jordan to declare war on Israel for
    water useage.
  • Syria gets water from Jordan and the
    Euphrates-Tigris rivers. Syria is closest to
    headwaters for Jordan River. They plan to build
    many dams for water diversion. This will limit
    water going to Jordan and Israel.
  • Israel threatens to destroy dams in Syria.

Tigris-Euphrates River
  • Turkey is situated at the headwater and they
    plan to build 22 dams along the upper Tigris and
    Euphrates for hydroelectric plants and for
  • Turkey plans on diverting water from dams via
    pipelines to Saudi Arabia, Kuwait and possibly
    Syria, Israel and Jordan.
  • Syria gets 90 of its water from the Euphrates.
  • Iraq will be left with very little water.

Nile River
  • Ethiopia control 85 of the headwaters.
  • Sudan uses approximately 10 .
  • Egypt the last to get water along the Nile
    (5). Egypt has a thin area of irrigated
    cropland, the rest of Egypt is desert.
  • PROBLEM Egyptian population grows by 1 million
    every 9 months!

What Can Egypt Do?
  • Declare war on Sudan and Ethiopia
  • Decrease population growth
  • Save water by improving irrigation efficiency and
    drought resistant crops
  • Spend 2 billion dollars and pump water from Lake
    Nasser (reservoir at the Aswan High Dam)
  • Import more grain to feed population
  • Work out water-sharing agreements with other
  • Suffer human and economic losses.

How Can Water Problems Be Resolved?
  • 1. Decrease population!
  • 1.2 billion lack access to clean drinking water
  • 2.2 billion live without Sewage Treatment Plants
  • 2/3 of the world households do NOT have running
  • Must be a global commitment to sharing this rare
    and valuable resource sustainably!
  • Build dams to store water in (reservoirs)
  • Transfer water from other places.
  • Build desalination plants (USA engineers)
  • Improve efficiency in water usage
  • Conserve water.

Why Is Water Wasted In the USA?
  • Artificially low prices of water resulting from
    government subsidies (externalities not including
    in your water bill).
  • Promotion of growing water thirsty crops such as
    alfalfa in California and Arizona! The
    government makes water SO cheap and easily
    accessible through water transfer from Colorado
    River that farmers grow these crops.
  • The US Bureau of Reclamation supplies ¼ of all
    water used to irrigate lands to the western USA
    under Long-Term Contracts at greatly subsidized
    prices from our taxes!
  • Watershed Management is divided between state and
    local governments in the western USA, there is
    not 1 Authority in control. Long Island has a
    Regional Water Authority (Suffolk County Water
    Authority) and we are in much better shape, but
    water is still ridiculously cheap.

Suffolk County Water Authority
  • Annual Reports on the Quality of Your Drinking
    Water are mailed out each spring to each resident
    in Suffolk County.
  • You can view them online as well.
  • www.scwa.com/residential/yourdrinkingwater.cfm

How Can We Conserve Water in the USA?
  • Efficiency improvement
  • Flood irrigation through gravity flow
  • Center-pivot sprinklers (low to ground less
    evaporation. (costs are high initially farmers
    dont use them)
  • Drip Systems release trickle of water near
    plant roots. High initial costs.
  • Computer controlled systems monitor soil
    moisture and turn on irrigation systems as needed
    (high initial costs)
  • Switch to xerophytic crops (little water needed)
  • Consumer should pay true cost of water (include
  • Provide subsidies for conservation methods that
    have high initial start-up costs!
  • Treat wastewater to irrigate non-edible crops.

What You Can Do
  • Turn faucet off when brushing teeth (saves 9
    gallons of water)
  • Fill up sink when shaving (saves 14 gallons of
  • Fill kitchen sink with water to wash pots and
    pans (saves 25 gallons of water)
  • When washing car, do not leave hose running
    (saves 150 gallons of water)
  • Self service car wash uses only 10 gallons of
  • Sponge and bucket uses only 15 gallon of water.
  • Flushing a toilet uses 5-7 gallons of water put
    a displacement device in tank and reduce it to
    2-3 gallons of water per flush.

What Can You Do?
  • Install low flow shower head. Decreases water
    use by 35 gallons for every 5 minutes you are in
    the shower.
  • Reduce the time spent in the shower!
  • Install low flow aerator faucet heads (4.00 at
    Home Depot or Hardware Store). Reduces water use
    by 50.
  • Use Phosphate-free detergents (Mandatory in
    Nassau and Suffolk) to decrease cultural
  • To Prevent Groundwater Contamination DO NOT
    dispose of paint, paint thinner, oil, grease or
    any other material labeled as hazardous or toxic
    into the environment or down the drain.
  • Town of Islip has special pick ups through WRAP
    program (1 in fall, 1 in spring) OR you can bring
    these materials to the Islip Town recycling

Groundwater Contamination
  • Groundwater is the primary source of drinking
    water and irrigation.
  • Contamination Sources
  • a. Livestock waste
  • b. Underground storage tanks (leak fuel and
  • c. Landfills (leach materials breaking down
    (metals, hdyrocarbons, etc.)
  • d. Abandoned hazardous waste sites leach heavy
    metals and solvents into groundwater.

Sanitary Landfill
Groundwater Protection in USA
  • Clean up is VERY expensive and technically not
  • US Safe Drinking Water Act, 1974 EPA
    established national drinking water standards e.
    0 coliform bacteria colonies per 100mL of water.
  • (Recall Clean Water Act does not protect

  • 1992 survey showed that 40 of the US drinking
    water contained parasitic organisms of
    Cryptosporidium sp., but not Giardia sp.
  • 1996 EPA mandated that ALL Public Water
    Suppliers (Suffolk County Water Authority) test
    for Cryptosporidium sp., but not Giardia sp.
  • There are 255 chemicals and compounds that the
    government requires we monitor in our drinking

Cryptosporidium sp.
Giardia sp.
Who Has Too Much Water?
  • When there is too much water or soils are
    persistently saturated, rain events can cause
    disastrous flooding.
  • Humans have contributing to increased flooding
  • a. deforestation
  • b. Mining
  • c. Overgrazing
  • d. urbanization (hard surface increase leads to
    infiltration decrease)

  • 123 million people in one of the poorest
    countries in the world and 80 of the population
    live along the shoreline where there are rich,
    fertile soils.
  • Average per capita GNP 260.00 71 cents/day!
  • Monsoon season brings continuous flooding during
    the summer months. It appears to be cyclic and
    that every four years there are significant
    monsoonal events since the 1970s (historically
    it was about every 50 years!)

Why Does Bangladesh Flood So Frequently?
  • Rapid population increase has changed the natural
    character of the land by
  • Deforestation which has promoted significant soil
  • Overgrazing
  • Unsuitable farming (steep slopes) and unsound
    farming practices on these slopes.
  • Cleared coastal mangrove forests to provide land
    to grow rice. They have removed the wetland
    structures and decreased or removed the functions
    they need to survive along the coastlines.
  • No money to restore mangrove swamps!
  • RESULT Millions of homes are destroyed each
    year, thousands of people drown. 30 million
    people become environmental refugees each year.

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How Do We Reduce Flood Risks?
  • Channelization to divert water away from
    communities can have both positive and negative
    effects. (Florida Everglades are destroyed from
    ACE water diversion)
  • Build levees and dams when they break
    disaster (Hurricane Katrina)
  • Restore wetland systems (never achieve 100
    replacement of structure and functions)
  • Establish Flood Plain Management Plans How
    about dont build in the flood plain?!!

  • Federal Emergency Management Agency
  • Provide Flood Plain Maps for every County in the
    USA. Designed for Insurance Companies.
  • Delineate 500 year storm flood elevation
  • Delineate 100 year storm flood elevation
  • Delineates entire flood plain area.

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