Freshwater Water Resources List of supplies for today

Freshwater

Water Resources List of supplies for today: 1. Vocabulary from last night 2. Notes pages for all group members 3. 3 -4 markers 4. Big sheet of paper

Unconfined Aquifer Recharge Area Evaporation and transpiration Evaporation Precipitation Confined Recharge Area Runoff Flowing artesian well Recharge Unconfined Aquifer Infiltration Water table Less permeable material such as clay Infiltration Stream Well requiring a pump Lake Unconfined aquifer Confining impermea ble rock layer Fig. 14 -3, p. 308

On your big paper… n Collaborate together and put your words into 4 -5 different categories according to their likes and differences. (NO: my vocab, bob’s vocab etc. )

n Put stars by surface water sources n Square your ground water sources n Circle uses of water n Underline ways we control water

Surface water: n Flood plains n Riparian zone n Lakes (oligotrophic, Mesotrophic, Eutrophic) n Rivers n Ponds n Wetlands

Ground water n Aquifers (Confined and Unconfined) n Water table n Springs n Artesian Wells

Uses… n Furrow irrigation n Flood irrigation n Spray irrigation n Drip Irrigation

Controlling water n Levees n Dikes n Dams

Sustainability (if you have them) n Fish Ladders n Desalinization n Hydroponic agriculture

On your notes n List and define the works for ground water and surface water in your spiral. n Try to see if you can label the diagram

You should be able to do (#’s 1, 4, 5, 6, 7, ) n n n n n 1. Aquifer 2. confining zone 3. Unsaturated zone 4. water table 5. confined aquifer 6. unconfined aquifer 7. artesian wells 8. water table well 9. flowing artesian well

A. Types of Water Surface water n Lakes, streams, rivers Ground Water n Absorbed in to the ground after a rain. n More than 50 percent of the people in the United States. n The largest use of ground water is to irrigate crops. n We get ground water out of the ground by wells

C. Surface FRESHWATER LIFE ZONES 1. Standing (lentic) water such as lakes, ponds, and inland wetlands. 2. Flowing (lotic) systems such as streams and rivers. Figure 6 -14

B. Ground Water 1. 2. 3. 4. 5. 6. Ground water is the water that fills the empty spaces and cracks. The top of the water in the soil, sand, or rocks is called the water table Water seeping down from the land surface adds to the ground water and is called recharge water. Aquifer is the name given to underground soil or rock through which ground water can easily move Some wells, called artesian wells, do not need a pump. These wells are drilled into an artesian aquifer, which is sandwiched between two impermeable layers.

C. Surface FRESHWATER LIFE ZONES 1. Standing (lentic) water such as lakes, ponds, and inland wetlands. 2. Flowing (lotic) systems such as streams and rivers. (*) Figure 6 -14

D. Flowing Water Ecosystems Because of different environmental conditions in each zone, a river is a system of different ecosystems.

Natural Capital 1. Ecological Services of Rivers a) Deliver nutrients to sea to help sustain coastal fisheries b) Deposit silt that maintains deltas c) Purify water d) Renew and renourish wetlands e) Provide habitats for wildlife Fig. 12 -11, p. 267

Freshwater Streams and Rivers: From the Mountains to the Oceans n Water flowing from mountains to the sea creates different aquatic conditions and habita habit Figure 6 -17

1. Headwater Stream Characteristics n. A narrow zone of cold, clear water that rushes over waterfalls and rapids. Large amounts of oxygen are present. Fish are also present. Ex. trout.

2. Downstream Characteristics n Slower-moving water, less oxygen, warmer temperatures, and lots of algae and cyanobacteria.

Standing Water Ecosystems Lakes, ponds, etc.

Life in Layers n Life in most aquatic systems is found in surface, middle, and bottom layers. n 1. Temperature, access to sunlight for photosynthesis, dissolved oxygen content, nutrient availability changes with depth. n 2. Euphotic zone (upper layer in deep water habitats): sunlight can penetrate.

Lakes: Water-Filled Depressions n Lakes are large natural bodies of standing freshwater formed from precipitation, runoff, and groundwater seepage consisting of 3. 4 zones n Littoral zone (near shore, shallow, with rooted plants). Limnetic zone (open, offshore area, sunlit). n Profundal zone (deep, open water, too dark for n photosynthesis). n Benthic zone (bottom of lake, nourished by dead

Littoral Zone n. A shallow area near the shore, to the depth at which rooted plants stop growing. Ex. frogs, snails, insects, fish, cattails, and water lilies.

Limnetic Zone n Open, sunlit water that extends to the depth penetrated by sunlight.

Profundal Zone n Deep, open water where it is too dark for photosynthesis.

5. Thermal Stratification

Lakes: Water-Filled Depressions Figure 6 -15

Definition n The temperature difference in deep lakes where there are warm summers and cold winters.

Lakes: Water-Filled Depressions n During summer and winter in deep temperate zone lakes the become stratified into temperature layers and will overturn. This equalizes the temperature at all depths. n Oxygen is brought from the surface to the lake bottom and nutrients from the bottom are brought to the top. n

Causes n During the summer, lakes become stratified into different temperature layers that resist mixing because summer sunlight warms surface waters, making them less dense.

Thermocline n The middle layer that acts as a barrier to the transfer of nutrients and dissolved oxygen.

Fall Turnover n As the temperatures begin to drop, the surface layer becomes more dense, and it sinks to the bottom. This mixing brings nutrients from the bottom up to the surface and sends oxygen to the bottom.

Spring Turnover n As top water warms and ice melts, it sinks through and below the cooler, less dense water, sending oxygen down and nutrients up.

Types of Lakes n Plant nutrients from a lake’s environment affect the types and numbers of organisms it can support. n Oligotrophic (poorly nourished) lake: Usually newly formed lake with small supply of plant nutrient input. n Eutrophic (well nourished) lake: Over time, sediment, organic material, and inorganic nutrients wash into lakes causing excessive plant growth.

Types of Lakes: Oligotrophic Sunlight Little shore vegetation Limnetic zone Profundal zone Oligotrophic lake Narrow littoral zone Low concentration of nutrients and plankton Sparse fish population Sleepily sloping shorelines Sand, gravel, rock bottom

Types of Lakes: Eutrophic Sunlight Wide littoral zone Much shore vegetation High concentration of nutrients and plankton Limnetic zone Dense fish population Profundal zone Eutrophic lake Fig. 7 -17 b, p. 139 Gently sloping shorelines Silt, sand, clay bottom

How we use our water and the problems we create

Problems

Too Much Water n Problems include flooding, pollution of water supply, and sewage seeping into the ground.

TOO MUCH WATER n Heavy rainfall, rapid snowmelt, removal of vegetation, and destruction of wetlands cause flooding. n Floodplains, which usually include highly productive wetlands, help provide natural flood and erosion control, maintain high water quality, and recharge groundwater. n To minimize floods, rivers have been narrowed with levees and walls, and dammed to store water.

TOO MUCH WATER n Comparison of St. Louis, Missouri under normal conditions (1988) and after severe flooding (1993). Figure 14 -22

TOO MUCH WATER n Human activities have contributed to flood deaths and damages. Figure 14 -23

Forested Hillside Oxygen released by vegetation Diverse ecological habitat Evapotranspiration Trees reduce soil erosion from heavy rain and wind Steady river flow Agricultural land Leaf litter improves soil fertility Tree roots stabilize soil and aid water flow Vegetation releases water slowly and reduces flooding Fig. 14 -23 a, p. 330

After Deforestation Tree plantation Roads destabilize hillsides Gullies and landslides Evapotranspiration decreases Ranching accelerates soil erosion by water and wind Winds remove fragile topsoil Agricultural land is flooded and silted up Heavy rain leaches nutrients from soil and erodes topsoil Rapid runoff causes flooding Silt from erosion blocks rivers and reservoirs and causes flooding downstream Fig. 14 -23 b, p. 330

Too Little Water

Examples n Examples include drought and expanding deserts.

Overdrawing Surface Water n Lake levels drop, recreation use drops, fisheries drop, and salinization occurs. Ex. Soviet Union (Aral Sea); the inland sea drained the river that fed into it. Now it’s a huge disaster (read pg. 322 in text). 1964 1997

Case Study: The Aral Sea Disaster n Diverting water from the Aral Sea and its two feeder rivers mostly for irrigation has created a major ecological, economic, and health disaster. About 85% of the wetlands have been eliminated and roughly 50% of the local bird and mammal species have disappeared. n Since 1961, the sea’s salinity has tripled and the water has dropped by 22 meters most likely causing 20 of the 24 native fish species to go extinct. n

Aquifer Depletion n This harms endangered species, and salt water can seep in.

Salinization of Irrigated Soil n Water is poured onto soil and evaporates. Over time, as this is repeated, nothing will grow there anymore.

U. S. Water Problems

Surface Water Problems n The polluted Mississippi River (non-source point pollution) has too much phosphorus. n In the Eerie Canal, which connects the ocean to the Great Lakes, lampreys came in and depleted the fish. The zebra mollusk is also a problem in the Great Lakes.

Effects of Plant Nutrients on Lakes: Too Much of a Good Thing n Plant nutrients from a lake’s environment affect the types and numbers of organisms it can support. Figure 6 -16

Effects of Plant Nutrients on Lakes: Too Much of a Good Thing n Cultural n eutrophication: Human inputs of nutrients from the atmosphere and urban and agricultural areas can accelerate the eutrophication process.

Mono Lake n (like the Dead Sea) This has a huge salt concentration due to man’s draining.

Colorado River Basin n These are dams & reservoirs that feed from the Colorado River all the way to San Diego, LA, Palm Springs, Phoenix & Mexico. So far has worked because they haven’t withdrawn their full allocations. See pg 306.

The Colorado River Basin n The area drained by this basin is equal to more than onetwelfth of the land area of the lower 48 states. Figure 14 -14

IDAHO WYOMING Dam Aqueduct or canal Upper Basin Salt Lake City UTAH NEVADA Lake Powell Grand Canyon Las Vegas Co Ri lora ve r do Lower Basin Denver Grand Junction UPPER BASIN COLORADO Glen Canyon Dam NEW MEXICO Boulder City CALIFORNIA Los Angeles ARIZONA Palm Springs San Diego All-American Canal Albuquerque LOWER BASIN Phoenix Yuma Mexicali Gulf of California Tucson 0 100 mi. 0 150 km MEXICO Fig. 14 -14, p. 318

Case Study: The Colorado Basin – an Overtapped Resource n The Colorado River has so many dams and withdrawals that it often does not reach the ocean. 14 major dams and reservoirs, and canals. n Water is mostly used in desert area of the U. S. n Provides electricity from hydroelectric plants for 30 million people (1/10 th of the U. S. population). n

Case Study: The Colorado Basin – an Overtapped Resource n Lake Powell, is the second largest reservoir in the U. S. n It hosts one of the hydroelectric plants located on the Colorado River. Figure 14 -15

Groundwater Problems n These include pollution, salt, and draining too much.

Other Effects of Groundwater Overpumping n Sinkholes form when the roof of an underground cavern collapses after being drained of groundwater. Figure 14 -10

Groundwater Depletion: A Growing Problem n Areas of greatest aquifer depletion from groundwater overdraft in the continental U. S. n The Ogallala, the world’s largest aquifer, is most of the red area in the center (Midwest). Figure 14 -8

Ogallala Aquifer n This is the world’s largest known aquifer, and fuels agricultural regions in the U. S. It extends from South Dakota to Texas. It’s essentially a non-renewable aquifer from the last ice age with an extremely slow recharge rate. In some cases, water is pumped out 8 to 10 times faster than it is renewed. Northern states will still have ample supplies, but for the south it’s getting thinner. It is estimated that ¼ of the aquifer will be depleted by 2020.

Global Water Problems

Impacts of Human Activities on Freshwater Systems n Dams, cities, farmlands, and filled-in wetlands alter and degrade freshwater habitats. n Dams, diversions and canals have fragmented about 40% of the world’s 237 large rivers. n Flood control levees and dikes alter and destroy aquatic habitats. n Cities and farmlands add pollutants and excess plant nutrients to streams and rivers. n Many inland wetlands have been drained or filled for agriculture or (sub)urban development.

Core Case Study: A Biological Roller Coaster Ride in Lake Victoria has lost their endemic fish species to large introduced predatory fish. Figure 12 -1

Core Case Study: A Biological Roller Coaster Ride in Lake Victoria n Reasons for Lake Victoria’s loss of biodiversity: Introduction of Nile perch. n Lake experienced algal blooms from nutrient runoff. n Invasion of water hyacinth has blocked sunlight and deprived oxygen. n Nile perch is in decline because it has eaten its own food supply. n

Stable Runoff n As water runs off from rain, it’s supposed to get into rivers, and finally off to the sea. But when we dam rivers, less goes to the ocean, meaning the brackish water (where the river hits the ocean) becomes more salty. This is the breeding ground for many fish and invertebrates. This harms the ecology of the area.

Population Growth n Problems include over-drawing fresh water, pollution, and overbuilding so that water can’t seep into the ground.

Sharing Water Resources n There are water wars out west. California bought the water from the Colorado River, but Arizona wants it. Who owns it? The same thing is happening in Texas. More water rights are sold than the actual amount of water. How do you share water? This is a problem all over the world.

Water Management

Dams and Reservoirs • Description: A dammed stream that can capture & store water from rain & melted snow. • Benefits: Hydroelectric power; provides water to towns; recreation; controls floods downstream • Problems: Reduces downstream flow; prevents water from reaching the sea (Colorado River) devastates fish life; reduces biodiversity.

USING DAMS AND RESERVOIRS TO SUPPLY MORE WATER n Large dams and reservoirs can produce cheap electricity, reduce downstream flooding, and provide year-round water for irrigating cropland, but they also displace people and disrupt aquatic systems.

Provides water for year-round irrigation of cropland Provides water for drinking Reservoir is useful for recreation and fishing Can produce cheap electricity (hydropower) Downstream flooding is reduced Flooded land destroys forests or cropland displaces people Large losses of water through evaporation Downstream cropland estuaries are deprived of nutrient-rich silt Risk of failure and devastating downstream flooding Migration and spawning of some fish are disrupted Fig. 14 -13 a, p. 317

Powerlines Reservoir Dam Intake Powerhouse Turbine Fig. 14 -13 b, p. 317

Case Study: China’s Three Gorges Dam n There is a debate over whether the advantages of the world’s largest dam and reservoir will outweigh its disadvantages. The dam will be 2 kilometers long. n The electric output will be that of 18 large coalburning or nuclear power plants. n It will facilitate ship travel reducing transportation costs. n Dam will displace 1. 2 million people. n Dam is built over seismatic fault and already has small cracks. n

Dam Removal n Some dams are being removed for ecological reasons and because they have outlived their usefulness. In 1998 the U. S. Army Corps of Engineers announced that it would no longer build large dams and diversion projects in the U. S. n The Federal Energy Regulatory Commission has approved the removal of nearly 500 dams. n Removing dams can reestablish ecosystems, but can also re-release toxicants into the environment. n

Water Diversion • Description: Damming a river to control where the water flows • Benefits: Keeps water where we want it- cities! • Problems: Drains wetlands, destroys land

Desalinization • Description: Removing salt from salt water • Benefits: Freshwater • Problems: Uses lots of energy; costs 3 -5 X’s more money; what do we do with the salt?

DESALTING SEAWATER, SEEDING CLOUDS, AND TOWING ICEBERGS AND GIANT BAGGIES n Removing salt from seawater by current methods is expensive and produces large amounts of salty wastewater that must be disposed of safely. n Distillation: heating saltwater until it evaporates, leaves behind water in solid form. n Reverse osmosis: uses high pressure to force saltwater through a membrane filter.

DESALTING SEAWATER, SEEDING CLOUDS, AND TOWING ICEBERGS AND GIANT BAGGIES n Seeding clouds with tiny particles of chemicals to increase rainfall towing icebergs or huge bags filled with freshwater to dry coastal areas have all been proposed but are unlikely to provide significant amounts of freshwater.

Harvesting Icebergs • Description: Towing massive icebergs to arid coastal areas (S. California; Saudi Arabia) • Benefits: freshwater • Problems: Technology not available; costs too high; raise temperatures around the earth.

INCREASING WATER SUPPLIES BY WASTING LESS WATER n Sixty percent of the world’s irrigation water is currently wasted, but improved irrigation techniques could cut this waste to 5 -20%. n Center-pivot, low pressure sprinklers sprays water directly onto crop. It allows 80% of water to reach crop. n Has reduced depletion of Ogallala aquifer in Texas High Plains by 30%. n

Drip irrigation (efficiency 90– 95%) Gravity flow (efficiency 60% and 80% with surge valves) Center pivot (efficiency 80%– 95%) Water usually comes from an aqueduct system or a nearby river. Above- or belowground pipes or tubes deliver water to individual plant roots. Water usually pumped from underground and sprayed from mobile boom with sprinklers. Fig. 14 -18, p. 325

Conservation • Description: Saving the water we have • Methods: recycling; conserving at home; xeriscaping; fix leaks • Benefits: Saves money; Saves Wildlife • Problems: bothersome to people; lack of caring; laziness