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Lithosphere and Groundwater. Lithosphere. solid rocky crust of the earth rocks on the surface are classified in 3 types igneous-cooled, molten rock, granite. Lithosphere. Sedimentary- sediments deposited in water and later made solid.
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Lithosphere solid rocky crust of the earth rocks on the surface are classified in 3 types igneous-cooled, molten rock, granite
Lithosphere Sedimentary- sediments deposited in water and later made solid. Metamorphic-Igneous and sedimentary rocks changed by hear &/or pressure Ex: marble, slate
Groundwater groundwater- water occurring beneath the surface used mostly as well water most occurs within lithosphere water table- the surface of ground water in a well
Groundwater point in the ground that is completely saturated with water. Water fills all spaces between soil and rock particles. (pores)
Groundwater Porosity- portion of the ground that contains spaces or voids. The total porosity of the material and size and continuity determine the volume of groundwater that is held available.
Groundwater U.S. gets 1/2 of our drinking water from groundwater
Groundwater Groundwater pollution 1988- EPA published a report 46 pesticides found in groundwater in 26 states only 9 were in concentrations higher than health advisory levels
Groundwater World Health Organization (WHO) each year 1/2 million people are poisoned by pesticides
Groundwater Herbicides & Insecticides are used in “large quantities” by farmers- one billion pounds of active ingredient per year
Groundwater Nitrates- EPA standard of no more than 10mg/liter of Nitrate Nitrogen in groundwater used for drinking. More than 21% of samples contained more than 10mg per liter in Kansas and Rhode Island
Groundwater 10-19% were in excess in California, Arizona, Oklahoma, and New York 5-9% were in excess in Colorado, South Dakota, Nebraska, Texas, Minnesota, Iowa, Illinois, Pennsylvania, Maryland, and Delaware
Groundwater in all of the other 50 states less than 5% tested high.
Controlling Groundwater pollution 1990 National Fertilizer and Environment Research Center set up 20 demo sites to control pesticide and nitrate pollution. Pierre, South Dakota Cone Ag Service
Problems of greatest concern metallic impurities in phosphoric acid fertilizer gypsum pond leakage treatment of contaminated soil reducing pollution from liquids rinsed from application equipment
Problems of greatest concern microbial techniques for waste treatment nitrate inhibitors for area techniques for sampling and testing groundwater developing better containments for chemigation and fertigation
Pesticides and groundwater most pesticides are synthetic organic compounds
Processes for loss from soil volatilization decomposition retention by soil transport by H2O
Fumigants relatively volatile vaporize at low temperature and move as gases through the soil Ethylene dibromide - used for nematode control
Ethylene dibromide very soluble in water not retained by soil commonly found in ground water
Synthetic Organics may be decomposed in different ways many are broken down rapidly in sunlight
Some pesticides react in water to form new compounds fungicide Captan reacts rapidly with water to form a hamless product
Some chemicals decompose very slowly and may persist for years example - DDT
Organic Matter is the most important soil particle in binding pesticide in the soil rather than going into the water
Primary transport of pesticides through the soil is by percolation of water down
Health Advisory Concentrations each of two animals is treated with a range of doses of the pesticide maximum dosage that produces no adverse effects in the more sensitive of the two species is divided by a safety factor (100)
Concentrations for a substance for which a safety factor of 100 has been used a 22 pound child would have to drink 26 gallons of water with the health advisory concentration per day every day
Continued to ingest an amount of pesticide equivalent to the max daily intake that produced no observable effect in the test animal of the same average weight
Avoiding pesticides in h2o alternative h2o sources distilling h2o ultraviolet light activated carbon filter
Nitrates and groundwater mostly from plant fertilizers introduction of legumes (alfalfa) plants that take Nitrogen from the air and put it into the soil
Nitrates and groundwater commercial fertilizers are used to supplement naturally occurring nutrients production of ag crops has increased due to the use of fertilizers
Nitrates and groundwater plants absorb only part of each nutrient present in the soil as the concentration of nutrients in the soil increases, % of total amount absorbed decreases greater residues are left in the soil
Nitrates and groundwater most chemical ions of fertilizers are bonded to and retained by the soil Nitrogen is not
Human Health Issues Problems related to Nitrates birth defects cancer migraines
Human Heath Issues nervous system impairment methomoglobinemia
Methomoglobinemia type of anemia hemoglobin carried Nitrogen instead of Oxygen to the body cells common cause of infant deaths
Groundwater use over drafts when more water is removed than is replaced by water from the surface 57% of water resource regions have over drafts
Groundwater use water table is falling in these areas most serious over draft is at the Ogallala Aquifer nations largest under parts of 8 states