Ch. 9: Water Resources

furrow irrigation

-oldest technique -easy and inexpensive -the farmer digs trenches or furrows , along the crop rows and fills them with water, which seeps into the ground and provides moisture to plants roots -65% of the water is accessible to the plants -other 35% either runs off the field or evaporates

agriculture

-the largest use of water in the world -as agricultural output has kept up with human population growth, the amount of water used for irrigation throughout the world has more than doubled

What are the benefits that dams provide to humans?

Dams allow for the retension of water used for consumption, they generate power using renewable resources, and they are used for recreation and controlling floodwaters.

If dams have both costs and benefits, how should we decide when a dam should be built?

Dams should only be built when the benefits of building them greatly outweigh the costs

Describe some ways that humans contribute to droughts.

Humans can change vegetation and abuse soil and making it infertile.

What is grey water? What can it be used for? Are there any concerns about re-using grey water?

It is waste water from showers, baths, washing machines, and bathroom sinks. Gray water can be used for watering plants and lawns, flushing toilets, and washing cars. United States and several other nations are worried about the possible chance of bacterial contamination from the gray water.

spring

a natural source of water formed when water from an aquifer percolates up to the ground surface -used for drinking water -also a natural source for freshwater aquatic biomes

artesian wells

a well created by drilling a hole into a confined aquifer -if pressure is great it can rise all the way up to the surface -no pump though is required to pump water from the ground

water is used by humans for agriculture, industry, and household needs

agriculture-70% industry-20% household needs-10%

efficient irrigation technology

benefits the environment by reducing water consumption and by reducing the amount of energy needed to deliver the water

dikes

built to prevent ocean waters from flooding adjacent land

Which of the following statements about the industrial use of water is not correct? a) it is used to refine metals b) it is used to create steam c) it is important to generating electricity d) it plays a role in making paper products e) its use is becoming less efficient

e) its use is becoming less efficient

levee

enlarged bank built up on each side of the river -prevents flooding

distillation

heat is used to boil water, which leaves its salt left behind as it evaporates

desalination or desalinization

process of removing salt from salt water

water table

the uppermost level at which the water in a given area fully saturates the rock or soil -surface of the ground water in a specific area

Water is abundant, but usable water is rare

- 97% of the Earth's water is in the ocean and only 3% is fresh

irrigation

-four techniques: furrow irrigation, flood irrigation, spray irrigation, and drip irrigation

flood irrigation

-involves flooding an entire field with water and letting the water soak in evenly -more disruptive to plant growth than furrow irrigation -more efficient than furrow irrigation -70-80% efficiency

Fill in the chart below for ways humans alter waterways. BE BRIEF! -levee -dike -dam -aqueduct

-levee:Large bank built up along a river Prevent flooding More floodplain land for commercial & residential use Fertility to floodplains are reduced -dike:Structure made to prevent the ocean from flooding land Prevent ocean from flooding land Helped countries in Europe to not be underwater They use fossil fuels to power their pumps -dam:Barrier across a river that controls flow of water Control flow of water Power modern turbines and create electricity in hydroelectric plants Interrupts the natural flow of water which causes the death of migrating fish -aqueduct:Canals that carry water from one place to another Carry water Made carrying water easier Cost a lot of money to make them

water ownership

-throughout the world, the issues of water rights and ownership have created many conflicts -one solution that has been proposed by economists is to allow all interested parties to openly compete for water and let market forces determine its price

industry

-water is used for generating electricity, cooling machinery, and refining metals and paper -ex: water that passes through a turbine at a hydroelectric dam is withdrawn from a reservoir to generate electricity, but that water is not consumed. It passes from the reservoir through the turbine and back to the river flowing away from the dam -some processes that generate electricity do consume water -rest of water goes into atmosphere -the refining of metals and paper also requires large amounts of water -paper indirectly uses water

Worldwide, list the three top uses of water, in order including percentages.

1st - Agriculture, 70% 2nd - Industrial, 20% 3rd - Household use, 10%

What is desalination or desalinization? Describe both processes: distillation and reverse osmosis.

Desalination: the process of removing salt from salt water Distillation: to heat or cool a liquid so it can be purified Reverse osmosis: When a liquid goes through a semi-permeable membrane which blocks more suspended or dissolved contaminants. It's the opposite way that osmosis goes through a semi-permeable membrane

What three household activities have the largest impact of water consumption in the United States?

Flushing toilets, laundry, and bathing

Describe 3 different ways industry uses water.

Generating electricity, refining metals and paper, and cooling machinery

How do humans contribute to flooding?

Humans can contribute to flooding by deforestation and urbanization

Discuss the ways in which humans manage water distribution

Humans have created a variety of ways to store and divert water, including levees, dikes, dams, and aqueducts. Each of these water distribution technologies has important benefits, but can also have negative environmental impacts. Humans have also developed technologies for the desalination of salt water.

How can lakes form? Give a few examples.

Tectonic plates: they can isolate a region of the ocean Glaciation: created large depressions in the land that then fill up with water

Identify the factors that will affect the future availability of water.

The future of water availability depends on water ownership, water conservation, economic development,and global change. Water ownership is a highly complex issue that involves the market value of water and our need to ensure that adequate supplies are available. Water conservation efforts include improvements in agricultural irrigation techniques, the increased use of recycled water in industrial processes, more efficient household appliances, planting less water- demanding landscapes, and simple water collection devices that collect rainwater and allow recovery and reuse of gray water.

Why are unconfined aquifers more likely to be contaminated than confined aquifers? Why are confined aquifers more likely to be depleted than unconfined aquifers?

Unconfined aquifers have high permeable layers, allowing chemicals and other harmful substances to enter. Confined aquifers can fall when too much pressure is on them.

How does hydroponic agriculture works? What are the benefits and drawbacks?

Under green house conditions, crop plants cultivate and grow with their roots deep in nutrient-rich solution, but with no soil. It uses up to 95% less water than most other irrigation techniques. They can also make more crops per hectare than other farms. Lastly, they can also grow under ideal conditions in every season of the year. However, hydroponic agriculture costs a lot of money.

Describe the concerns that scientists have regarding the pumping of water from confined aquifers

When a deep well is not heavily pumped, the recharge of the water table keeps up with the pumping. In contrast, when a deep well pumps water from an aquifer more rapidly than it can be recharged, it can form a cone of depression in the water table and cause nearby shallow wells to go dry.

saltwater intrusion

When salt water infiltrates an area with rapid plumbing, which makes the water in the wells salty

Explain how cones of despression near the coasts of continents can lead to saltwater intrusion of water wells.

When there are few wells along a coastline, the water table remains high and the resulting pressure prevents salt water from intruding. In contrast, rapid pumping of wells drilled in aquifers along a coastline can lower the water table. Lowering the water table reduces water pressure in the aquifer, allowing the nearby salt water to move into the aquifer and contaminate the well water with salt

dam

a barrier that runs across a river or stream to control the flow of water

reservoir

a body of water created by blocking the natural flow of a waterway

groundwater recharge

a process by which percolates through the soil and works its way into a an aquifer

The need to conserve water is widespread throughout the world. People who live in developed countries such as the United States can make some simple changes to conserve water. a) An older showerhead uses 150 L for a 10-minute shower, whereas a reduced-flow showerhead uses only 95 L. If you take one shower per day, how many liters of water would you save in 1 year if you replaced your older shower head? b) An older toilet uses 27 L per flush, whereas a replacement toilet uses only 6 L per flush. If you flush the toilet four times per day, how many liters of water would you save in 1 year if you replaced your older toilet? c) Now let's assume that you have a newer toilet that uses 6 L per flush, but you aare considering upgrading to a dual-flush toilet. If you flush the toilet four times per day, but three of those times you could use the 3 L flush, how many liters of water would you save in 1 year? d) If you made all three of the changes described in questions a-c, how much water, in total, would you save from going down the drain? e) If you lived in a family of four people, and you paid $1 for every 1,000 L of water your family used, how much money, in total, could your family save in 1 year with these water conservation improvements?

a) 20,075 L/year b) 30,660 L/year c) 33,945 L/year d) 54,020 L/year e) $54.02 /year

What percentage of Earth's water is fresh water? a) 3 percent b) 10 percent c) 50 percent d) 90 percent e) 97 percent

a) 3 percent

Which of the following statements about desalination is correct? a) distillation requires more energy than reverse osmosis. b) the brine left over from desalination is not harmful when returned to the ocean. c) large-scale desalination of water is affordable to all nations. d) desalination of ocean water is not yet a feasible endeavor e) most desalination occurs in the middle east

a) Distillation requires more energy than reverse osmosis.

Which of the following statements about aqueducts is correct? a) aqueducts designed as open canals can lose a lot of water via evaporation b) aqueducts are a modern invention c) aqueducts do not divert water from lakes d) aqueducts do not affect the amount of water remaining in rivers e) aqueducts move water from locations where the demand for water is high

a) aqueducts designed as open canals can lose a lot of water via evaporation

Which f the following is NOT a water conservation technique? a) flood irrigation b) reduced-flow shower heads c) recycling of industrial water d) dual-flush toilets e) front-loading washing machines

a) flood irrigation

Match the name to each description. Choices: oligotrophic lake, mesotrophic lake, eutrophic lake a. _________________ - Highly productive ecosystem with high levels of organic matter, murky water and thick mud on the bottom. Oxygen levels may be depleted and desirable fish populations are often low. b. _______________ - A deep lake with clear water that has low productivity, little organic matter and high oxygen levels. Desirable fish populations are usually abundant and the lake is visually attractive. c. __________________ - A productive ecosystem that has some organic matter, medium nutrient levels and somewhat clear water. A thick layer of decomposing organic matter is forming on the bottom of the lake and plants may be growing in the shallow zones near the lake boundaries. On particularly hot sunny days, oxygen levels may drop, but in general the lake has the oxygen to support desirable fish populations.

a. _______Eutrophic__________ - Highly productive ecosystem with high levels of organic matter, murky water and thick mud on the bottom. Oxygen levels may be depleted and desirable fish populations are often low. b. ______Oligotrophic_________ - A deep lake with clear water that has low productivity, little organic matter and high oxygen levels. Desirable fish populations are usually abundant and the lake is visually attractive. c. _______Mesotrophic___________ - A productive ecosystem that has some organic matter, medium nutrient levels and somewhat clear water. A thick layer of decomposing organic matter is forming on the bottom of the lake and plants may be growing in the shallow zones near the lake boundaries. On particularly hot sunny days, oxygen levels may drop, but in general the lake has the oxygen to support desirable fish populations.

What methods have wealthier, developed countries made to conserve water? Describe one option for each of the following activities: a. toilet flushing - b. bathing - c. laundry - d. outdoor usage - e. industry - f. runoff -

a. toilet flushing - toilets that only flush 6L of water or even 3L, dual-flush toilets also b. bathing - new reduced- flow shower heads c. laundry - front-loading washing machines d. outdoor usage - switch fake grass with water-efficient native landscaping e. industry - more efficient manufacturing equipment (gutter system) f. runoff - put trash cans at the bottom of driveways so runoff can be collected

Water ownership is complicated. a. Why is it harder to determine ownership of water than for many other resources? b. Briefly describe 3 water conflicts (from this chapter or previous units). c. How do economists suggest that we resolve these conflicts?

a.Since water travels it can belong to one place while also belonging to another because it is moving. b.India creating a plan to alter water from rivers that come from the Himalayas into Bangladesh. 1967 Arab-Israeli War had disputes over the use of water. In California, the state government agrees to allow certain amounts of water to suburbs, cities, and farmers, but the agreements outpace the exact amount of water that is accessible in many years. c.We should allow interest parties to openly fight for water and allow market forces actuate its price.

unconfined aquifer

an aquifer made of porous rock covered by soil, which water can easily flow into and out of

confined aquifer

an aquifer surrounded by a layer of impermeable rock or clay that impedes water flow

cone of depression

an area where there is no longer groundwater -all of the water has been withdrawn

Which of the following contrasts between confined and unconfined aquifers is correct? a) confined aquifers are more rapidly recharged b) only confined aquifers can produce artisan wells c) only unconfined aquifers are overlain by a layer of impermeable rock d) only unconfined aquifers have a water table above them e) only confined aquifers can be drilled for wells to extract water

b) only confined aquifers can produce artisan wells

Which of the following lists of agricultural irrigation techniques is in the correct order, from least efficient to most efficient? a) drip irrigation, furrow irrigation, flood irrigation, spray irrigation b) spray irrigation, furrow irrigation, flood irrigation, drip irrigation c) furrow irrigation, flood irrigation, spray irrigation, drip irrigation d) furrow irrigation, spray irrigation, drip irrigation, flood irrigation e) furrow irrigation, flood irrigation, drip irrigation, spray irrigation

c) furrow irrigation, flood irrigation, spray irrigation, drip irrigation

Which of the following statements about surface waters is not correct? a) historically, most rivers regularly spilled over their banks b) the largest river in the world is the Amazon River c) levees are used to make reservoirs d) dikes are human-made structures that keep ocean water from moving inland e) wetlands play an important role in reducing the likelihood of flooding

c) levees are used to make reservoirs

aqueducts

canals or ditches used to carry water from one location to another

ground water

clean water that is under the ground -found in aquifers -unconfined and confined

Which of the following statements about dams is not correct? a) dams are used to reduce the risk of flooding b) dams can cause increased water temperatures c) the water held back by a dam is called a reservoir d) fish ladders allow migrating fish to move past dams e) most dams are built to generate electricity

e) most dams are built to generate electricity

the future of water availability depends on many factors

how we resolves issues of water ownership and how we improve water conservation and develop new water-saving technologies as the world's population grows

eutrophic

lakes with a high level of productivity

mesotrophic

lakes with a moderate level of productivity

impermeable surfaces

pavement or buildings that do not allow water penetration -water from heavy rainfall events can't soak into the ground

Aquifer

permeable layer of rock and sediment that contains groundwater

hydroponic agriculture

the cultivation of crop plants under greenhouse conditions with their roots immersed in a nutrient-rich solution, but no soil -alternative to traditional irrigation -produce more crops per hectare than traditional farms -they can grow crops under ideal conditions -during every season of the year -also grow with little or hardly any use of pesticides

floodplain

the land adjacent to the river where excess water spreads onto

gray water

the wastewater from baths, showers, bathroom sinks, and washing machines

atmospheric water

water that is in the atmosphere -in clouds and other parts of atmosphere -essential to global water distribution

What are the costs of dams to human society?

Costs to build them is expensive. Construction causes relocation of communities.

Explain the factors that create an artesian well

The water in some confined aquifers is under tremendous pressure due to the impermeable layer of rock that surrounds it. Drilling a hole into a confined aquifer releases the pressure on the water, allowing it to burst out of the aquifer and rise up in the well.

List the negative impacts of a drought.

Smaller amount of crops and livestock, human lives being lost, and soil becoming brittle

oligotrophic lakes

lakes that have low productivity due t low amounts of nutrients such as phosphorous and nitrogen in the water

water conservation

-many developed countries have begun to find ways to use water more efficiently through technological improvements in water fixtures, faucets, and washing machines -one of the best ways to reduce water use and consumption is to produce more efficient manufacturing equipment -the growing population & the associated expansion of irrigated agriculture have increased global water withdrawals

spray irrigation

-more expensive than furrow and flood irrigation -uses a fair amount of energy -water is pumped from a well into an apparatus that contains a series of spray nozzles that spray water across the field, like giant lawn sprinklers -75-95% efficiency

households

-the quantity of water used in households depends greatly on the types of infrastructure available in a country -indoor water use- toilets, shower, sinks, drinking water -outdoor water use- watering lawns, washing cars, and filling swimming pools

drip irrigation

-uses a slowly dripping hose that is either laid on the ground or buried beneath the soil -drip irrigation using buried hoses is over 95% efficient -added benefit of reducing weed growth because the surface soil remains dry, which discourages weed germination -useful in fields containing perennial crops such as orchard trees, where the hoses do not have to be moved for annual plowing of the field

Describe two negative effects of over pumping groundwater.

Cone of depression: area where there isn't any groundwater left, rapid pumping of deep wells cause shallower and smaller wells to become dry. Saltwater intrusion: infiltration of salt water where groundwater pressure has been lowered from the effect of extensive drilling of wells.

Put the 4 irrigation techniques in order from most efficient to least efficient.

Drip irrigation (95% effective), spray irrigation (75-95% effective), flood irrigation (70-80% effective), and furrow irrigation (65% effective)

How do recent trends in global water consumption compare with recent trends in US water consumption? Given these trends, what do you think will happen to global water use in the near future?

Many countries like Australia and Turkey use gray water to replace for water in toilets so freshwater can be saved. However, the United States and several other nations don't allow the use of gray water. You are only allowed to use gray water in the U.S. if it is treated and transporting carefully so there won't be any contamination. If the world keeps replacing freshwater in toilets with gray water it will help preserve fresh water.

Identify Earth's natural sources of water

Most water on Earth resides in the oceans. Of the relatively small proportion that is fresh water, nearly three-fourths is tied up as ice and glaciers , leaving a small amount remaining in groundwater, streams, rivers, lakes, and wetlands. All of these sources of freshwater can be used by humans. Atmospheric water is an additional source of water, but it's availability ma vary seasonally as well as from year to year. Human activities can contribute to the negative effects of drought and flooding.

Eutrophication is a natural aging process for lakes, but when humans cause it, it is called cultural eutrophication. What are the differences between natural eutrophication and cultural eutrophication?

Natural: fresh nutrients Cultural: waste

What are the negative impacts of dams on the environment?

Some of the negative impacts of dams on the environment are reduced biodiversity from impeded migration, increased sediment load, no estuaries, less plant growth, and warmer water temperatures which can result in increased toxic algae growth.

In the US, we rarely think about our drinking water. Why would someone in a less developed country think about drinking water on a daily basis?

They don't have healthy drinking water so they tend to worry about it way more than we do.

Describe the major human uses of water.

Water is used in agriculture, industry, and households. Agricultural uses of water include several different methods of irrigation as well as the developing field of hydroponic agriculture. Industrial uses of water include the generation of electricity, the refining of metals and paper, and the cooling of machinery. In households, water is used primarily in bathrooms and for washing clothes. Per capita water use varies tremendously by country. Developed countries tend to use more water than developing countries, where many people have access to only a few liters of water per day.

What kinds of household water would not be reusable without treatment?

Water we flush from toilets and washing machines after being used.

which of the following lists household water uses in the correct order, from highest to lowest? a) toilet > laundry > cooking and drinking > bathing b) toilet > bathing > laundry > cooking and drinking c) laundry > bathing > toilet > cooking and drinking d) bathing > toilet > laundry > cooking and drinking e) bathing > toilet > cooking and drinking > laundry

b) toilet > bathing > laundry > cooking and drinking

surface water

clean water above the surface -streams, rivers, ponds, lakes, and wetlands