bounded above and below by low permeability units (i.e.,

clay)

– if a well penetrates this aquifer, water will rise above the

level of the upper confining unit

Subsurface water that

saturates sediments and rocks.

Meters to kilometers below the surface

• is the primary supply of drinking water for the western US
• – CA ~ 60 billion liters per day
• It is available even during drought
• – It is somewhat protected from contamination
• – Time lag
• – Some bacteria and viruses are naturally filtered out
• – We don’t need to build surface reservoirs
• – 98% of Earth’s unfrozen fresh water supply!

Level water would rise to in a well

– Near the top of the saturated zone

Most precipitation in the summer as flashy thundershowers. Most water runs off

quickly

• the winter when snow melts and percolates into ground.

The water-table

elevation has changed

because of?

ground

water withdrawal

• The Compact apportions the waters of the Upper Rio

Grande Basin amongst the three States

• The Compact does not affect the obligations of the United

States to Indian Tribes or impair their Rights

• San Juan-Chama Project Water is not subject

to Compact apportionment

• Colorado and New Mexico Credit Water

is held in Elephant Butte Reservoir

• Colorado may accrue up to 100,000

acre-feet of debit

• New Mexico may accrue up to 200,000

acre-feet of debit

• Spills from Elephant Butte Reservoir

eliminate credits and debits

• Silvery Minnow
• Tamarisk (salt cedar)

• 1960 Aral Sea
• Fourth largest lake
• in the world
• Internally drained
• 1960 Soviets divert ½ of
• all incoming river water
• for cotton irrigation.
• Next 30 years, lake dries
• up – shoreline recedes
• and salt content increases

• Lake area decreases by over 60%

• Loss of fresh water supply for regional

population

• Collapse of Aral Sea fishing industry and

lake ecosystem

• More extreme climate (colder winters and

hotter summers) around lake margin

• Massive dust storms from former lake bed

What is life?

• Four criteria:

– Metabolism - chemical reactions by which the

organism gets energy

– Growth - ordering molecules to make larger

ones

– Reproduction - cell division and self-replication

– Evolution – adaptive changes in the

characteristics of organisms over many

generations

Autotrophs

• Organisms that produce their own energy

– Photosynthesis: from light energy

– Chemosynthesis: from chemicals (black smokers)

• Organisms that derive energy by feeding on

other organisms or compounds

– Oxygen intolerant organisms use fermentation

– Oxygen tolerant organisms use respiration

• Involves the ordering and organizing of atoms

and small molecules to make larger molecules

– Polymerization or crystallization

• The ordered pattern of atoms or molecules is

replicated throughout the structure

• Growth in living matter occurs by polymerization

– Polymerization absorbs energy

• Growth requires energy; through metabolism

1. The cell
2. Prokaryotes
3. Eukaryotes

are cells that do not have a

true nucleus

is the structural and functional unit

of all living organisms

Species are organized into taxonomic

ranks of 3 domains comprising 6 kingdoms

• Archaea

• Bacteria

• Eukarya

– Animals, plants, fungi and protists

Forms of life are organized into groupings

according to their genetic and evolutionary

relationships

The two fundamental requirements for

any life-supporting system are

1. Flow of energy

– Functions of energy

– Pathways through which it flows

– The basic function of energy is to make the

production of organic matter possible

2. Continual recycling of chemical elements

– In addition to oxygen, photosynthesis

produces carbohydrates, which build the

body mass of autotrophs

– Primary production

build body mass by eating

other organisms

– Secondary production

Primary producers convert energy and

inorganic compounds into biomass

– 1st: autotrophic organism produces organic

matter in its body

– 2nd: uses this organic matter as fuel in

metabolism and respiration, releasing heat

– 3rd: stores some of the organic matter for

future use

is pathway by which energy

moves through an ecosystem

Each group of species that is the same

number of steps away from the original

source of energy

The earliest fossil found is from the

Archean at 3.55 billion years old

– Chemical signatures of biologic processes

have been dated to older rocks

– Beginning 542 million years ago

• Introduction of internal and external skeletons

• A time of almost unbridled growth and diversity

in the marine environment

• The pace of evolution increased dramatically

• Most major modern groups of organisms

emerged and established body plans at this time

• Slipped disks in vertebral column causing dino debilitation.

• Hormone problems

• Decrease in sexual activity

• Blindness due to cataracts

• Diseases and epidemics

• Parasites

• General stupidity

• Competition with other animals (esp. mammals)

• Overpredation

• Floral Changes

1. Climate too hot, too cold, too wet, too dry

2. Volcanic emissions

3. High levels of CO2 asphyxiating dinosaur embryos

1. Cosmic radiation and UV radiation causing mutations

2. Sunspots

3. Impact of large asteroid or comet

No crater but large area of trees blown down in circular pattern

Impact, Aerial Burst, or Space Aliens?

– A species in imminent danger of extinction

– Currently about 1500 in North America

– More than 16,000 worldwide

– A species that has shown a significant

decrease in population or range, or shows

signs of imminent local extinction

happens when

large tracts of natural area are broken up

into smaller patches by roads and other

disruptions

– The expansion of desert into previously productive

land areas

– Medical and pharmaceutical

– Direct economic value

• Food, lumber…

– Recreational and tourism value

– Aesthetic value

– Ecological benefits and services

– Deep ecology

– Holistic and integrated vision of the

environment in which the cumulative value

of species and ecosystems together is

worth incalculably more than individual

species considered separately