Chapter 6
Our Forests
Grasslands
National Parks and Preserves
Chapter 10
Water is a Resource
Where is the Water?
The Pollution of Water
Chapter 7
Global Food and Nutrition
How much food is enough food?
What do we eat?
Precious Soil
Chapter 11
Energetic Planet
Minerals and Rocks
Geology and Mineralogy
Resource extraction and its Effects
Conserving Resources
Geological Hazards
Chapter 6
Our Forests
It is amazing to think that nearly 60% of our planets land mass is made up of forests and grasslands. We rely heavily on these ecosystems for most of the resources that we need to sustain our lives. Beyond that, we need these areas to sustain what we forget that we need. Climate stability, air and water purification and wildlife habitat only scratch the surface of what forests and grasslands provide for our planet.
While the term forest generically means any area where trees cover more than 10% of the area, there are more specific terms that describe each type of forest. For example a savanna (where only 20% of the area has trees) is as much a “forest” as a closed canopy forest (where tree crowns cover most of the ground). While Tropical forests and the boreal forest (made up of coniferous and deciduous trees that stretch across North America as well as Europe and Asia) are the most abundant types of forests in the world; they are also the forests that suffer the most deforestation.
The wood harvested from tropical and boreal forests can be found in every aspect of our daily lives, from the paper we write on to the house we live in. Over half of the wood that is cultivated is used for firewood. More than 50% of humans use firewood as a primary source of energy and heat. Paper pulp is increasing in demand across the globe. (Interestingly, I heard a comment this week about the more our world tries to become paperless, the more paper we use.) Countries such as ours use over 80% of the wood harvested but produce less than half of the wood harvested for industrial purposes.
Tropical forests have suffered heavy losses in the last hundred years. What once covered more than 7.7 million miles a hundred years ago less than half of that still remains. The deforestation (according to the FAO) is occurring at a rate of 0.6% a year. Brazil claims the largest tropical forests, but has also seen over 6.6 million acres of forest destroyed by forest clearing and fires.
There are many causes of deforestation. In dense tropical forests the removal of one tree can bring down several because the branches and vines are so tightly wound together. Once a small path into the forest has been forged the area becomes accessible to other groups that cause more damage to the forest. As our forest landscapes change it will have adverse effects on rain patterns that will cause our climates to drastically change.
Clear cutting (which requires all of the trees in a designated area to be cleared) is a common method of harvesting in the United States. While this method was originally thought to be a good way of removing all of the dead lumber from the area, research later showed that these areas were important to the local ecosystem as well as important for nutrient recycling. Alternative methods of harvesting emerged in the forms of shelterwood harvesting (removal of only mature trees) and selective cutting which only require the removal of a very small percentage of the mature trees in an area and puts that method of logging on a ten to twenty year rotation.
Forest fires seem to have made a huge impact on our lives and how we treat our local forests. After a series of huge fires in the 1930’s the United States Forest Service began implementing policies for fire control. This involved implementing laws of campfires and other blazes on public land. Recent research suggests that controlling or suppressing fires may not be the best way to go. Some forests rely on natural fires for regeneration. By suppressing fires more debris gathers on the forest fire, creating more fuel for a much larger and more dangerous fire. In 1988 Yellowstone National Park suffered a fire that burned more than 700,000 acres. Although several thousand firefighters (including my father) and thousands of military personnel arrived to help extinguish the fire, it was the cool moist weather of the late autumn season (a natural intervention) that finally brought the fire to an end. Today the ecosystem has begun to rebuild and show the world the natural process of regeneration.
In recent years, many countries have begun to see the value of our forests and begun to shift their focus to conservation. Today 14% of our global forests are in some form of protection. During the 2009 Copenhagen Climate Conference the global leaders agreed to fund REDD (Reducing Emissions from Deforestation and Degradation). This program has the goal of protecting forests and restoring destroyed forest areas. While REDD is still a year away from full implementation, they have plans to plant mass amounts of degraded forests. The United Nations surmises that it may take over $20 billion dollars a year to fund REDD, but the long term benefit will far outweigh the cost.
Some forests remain undiscovered or uncultivated. These forests are called old-growth forests and maintain ecosystems that have been undisturbed by human expansion. While old-growth forests have remained safe from our current cultivation and deforestation practices the rest of the global forests remain in danger and in need of protection.
Our Grasslands
Grasslands are often forgotten when we calculate where we get our resources from. However, second to forests we rely on grasslands. The term grasslands loosely encompass prairies, savannas, steppes and open woodlands. These areas take up around 25% of our global land mass. 12 million miles of these areas are used for pastures and grazing lands and over another 12 million miles are used for raising livestock and grazing. Sheep, goats, camels, buffalo and other animals graze on this land and provide us with a large amount of our nutrition.
Unfortunately, the nature of grasslands lends them to be developed by humans for landscaping and cropland. Because of this the rate of grassland disturbance is more than three times that of the tropical forests.
Grazing walks a very fine line; it can be both damaging and sustainable. Ranchers who allow their livestock to graze an area to a barren state create a damaging environment that is difficult if not impossible to regenerate. However, ranchers and pastoralists that schedule the grazing in different areas based on rainfall and seasonal plant conditions, keep their livestock as well as the grassland healthy and replenished.
Overgrazing is one of the biggest challenges that face grasslands. When the land is overgrazed it is open to growing catci, mesquite, and sage that make the area unfit for grazing. Conservations have asked for a ban on grazing on all public land for this very reason. Currently, ranchers pay the government nominal fees to graze on public land which is much cheaper to them than leasing private land for grazing. While conservationists disagree with their way of life, ranchers contend that they are upholding old traditions of Western culture.
Despite the disagreement, ranchers are looking for new and better ways to graze their livestock. One of these methods is rotational grazing. This type of grazing allows the livestock to graze to an extent, heavily trample and heavily fertilize (with manure) the area before the rancher rotates to a new location. Perhaps there will be a middle ground for ranchers and conservationists.
Our National Preserves and Parks
The concept of a national park or preserve has been around for almost as long as humans have been destroying land for its resources. The ancient Greeks protected sacred groves for religious purposes as well as segregated tree sheltered agoras for ordinary citizens to enjoy. However, it was not until the second half of the twentieth century that natural spaces for recreation were developed. Encouragingly, today nearly 14% (52 million acres) of land is protected by preserve or park.
Venezuela claims to have the largest percentage of its land protected (a staggering 66%). In contrast the United States only claims 22% of its land is protected. Brazil, with the largest amount of tropical forests, has over 1.5 million miles of protected land (the largest total protected area in the world). In 2006 Para ( a northern state of Brazil) worked with the Conservation International organization to protect even more areas that line with Suriname and Guyana.
Greenland also has large protected areas of land, as well as Saudi Arabia and Canada. Unfortunately, these protected areas are not all safe. They are threatened by dams and forestry exploration that risk erosion and loss of wildlife habitats. Even National Parks in the United States suffer from over use and degradation. Yellowstone National Park and the Grand Canyon are at risk off over use and destruction merely because people flock to these areas to gaze on their beauty.
In an effort to stop some of the damage being caused by human interference, parks like Zion National park and Yosemite have banned the use of personal vehicles inside the park. Visitors must park in distant locations and take busses that are clean burning or electric to the location. Extreme measures have been taken across the globe to protect both parks and preserves. In South Africa, soldiers have “shoot to kill intruders” orders in order to protect the preserves from wildlife poaching. In the end it is crucial for each one of us to tread with care on our planet and fight for its preservation. That is not to say we cannot continue to harvest it’s amazing resources, but protection and preservation of our planet must come first and without fail.
As waste from a point source of pollution enters the water, the amount of oxygen in the water decreases. Only micro organisms that consume the waste or rough fish that feed on both the microorganisms and the waste can survive in the depleted area. Further downstream as the water begins to become more oxygenated, more species begin to spawn and survive, this continues until the water is clean again.
Meat is a luxury that many developing nations to do have. For many, the ability to eat meat is a sign of wealth. It takes eight times the amount of grain to feed a cow than it does to make a loaf of bread. While this meat provides a valuable protein to our diet, it is also very expensive (in comparison to vegetables and grains) to produce.
Sadly our production of this greatly desired meat can and does cause a great amount of pollution to our environment. The animal waste can contain harmful contaminates that then seep into the soil and pollute ground water. Also, in order to allow these animals to graze, forests and other ecosystems must be cleared out to make room.
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Chapter 10
Water is a Resource
In fact, water is a primary resource. Without it we could not survive more than a handful of days. Water is needed in every facade or our lives, from agriculture to industry and transportation and , not to mention that our bodies are made up of over 60% water. Our planet holds 370 billion gallons of water!
This water constantly cycles through our planet via the hydrologic cycle. Through the hydrologic cycle water evaporates from moist surfaces, falls through rain or snow, and eventually makes its way back to the ocean. While over 90% of this water ends up back in the ocean, the ocean also contributes the majority of the amount of water that starts this cycle.
In the tropics the trees and vegetation return 75% of the moisture they receive during back into the atmosphere. The uneven distribution of water throughout the planet is caused by the uneven distribution of sunlight around the globe. The hydrologic cycle relies on the sun to evaporate the surface water which will later become rain and snow. Landscape plays a huge factor in the amount of rainfall or snowfall a region will see. Higher latitudes will see less rainfall than lower regions (many tropic areas are right along the equator). Mountains also play a part. Windward sides of mountains will see more rainfall and have large rivers, while the opposite side of the mountain (leeward) can be arid and dry (the leeward side of the mountain is called the rain shadow).
Where is the Water?
While the majority of the planets water in the oceans that have over 90% of the planets biomass, it is the fresh water that is needed. Surprisingly, only .02% of the globes is in a form accessible to us! Glaciers, ice caps, and snow field hold 90% of the 2.4% of fresh water. These place provide fresh water for billions of people. However, as our climate shifts and the glaciers and ice caps begin to melt, the fear of losing this valuable water source becomes more real. If the warnings that the glaciers could disappear before the end of this century are true, the planet will suffering will be momentous.
The largest compartment of liquid fresh water can be found in ground water. While plants get their moisture from a shallow layer of soil called the zone of aeration, the lower levels of this soil can contain pores that are full of water (known as the zone of saturation). Most wells get their water from the first layer of the zone of saturation called the water table.
Water that finds itself moving through porous rock deep underground, ends up in underground aquifers. Water can travel through these layers of rock as quickly as a few hours or several years depending on the type of stone. If the aquifer is under a lot of pressure, then wells above it can flow freely on the surface. These areas are called artesian wells. While there are places called recharge zones that fill the aquifer, it is also easy for pollutants to enter the aquifer from these areas.
It is easy to understand why our most valuable source of fresh water is flowing surface water. However, without groundwater seepage, rain fall, and melted snow runoff stopped, our precious lakes and rivers would dry up in record time. 16 of the world’s largest rivers have nearly half of all of the surface water on the planet flowing through them. Rivers have become essential to the world for water, but also for transportation and food (in the form of the fish and animals that live there). Lakes still have more than 100 times the water that all of the rivers and streams of the world combined have. The problem lies in that most of that water is held in just a handful of the world’s largest lakes. Lakes, like rivers, provide water, food, and transportation to the communities around them.
Wetlands also play a very important role in the quest for fresh water. We often overlook their importance, but they are spread over large areas and contribute greatly to the hydrologic cycle. Their lush vegetation helps hold back runoff so that it can seep into the much needed underground aquifers and prevent flooding of the surrounding areas.
Our atmosphere also contains a very small amount of our planets water resources (about 0.001%). Despite this our atmosphere is an important bus for the hydrologic cycle. Water molecules are only in the atmosphere for a short time before it falls to the earth and continues the cycle.
The Pollution of Water
I think that it is safe to assume that we are all very well aware of water pollution. Whether or not we grasp the severity of the issue is yet to be determined, but we are aware there is an issue. Whenever water is physically, biologically, or chemically altered in a way that could cause harm to the living organisms that are in the water or make the water unsuitable for use, it is polluted. While some pollution of water can be natural, most is human caused.
Point sources of pollution come from a specific location like a factory, mine or oil well. Non point sources are harder to regulate or watch because they have no specific location where they discharge. Point sources are predictable, but non point sources are erratic and have no pattern. One of the best examples of a non point source would be our atmosphere. The atmosphere can deposit chemicals that we release into it by way of rain or snowfall. This then contaminates the runoff into lakes and rivers taking with it the chemicals.
There are biological forms of pollution. These include pathogenic organisms that are in the water and cause disease. These include diseases like typhoid, cholera, polio and hepatitis. Other diseases like malaria and yellow fever are caused by insects that are born of aquatic larvae. Even in our modern age of technology and medicine these pathogenic organisms are the cause of over 25 million deaths each year.
Sadly, the cause of these pathogens is greatly the result of untreated human waste (the next time I drive by a water treatment plant I will not wrinkle my nose but be thankful for its purpose). Animal waste also contributes to these diseases.
Wealthy countries have the benefit of water treatment plants and drinking water that is purified with chlorination, which has eliminated the risk for most of the disease causing pathogenic organisms. However, poorer countries can hold them responsible for two thirds of the child mortality.
The pollution caused by a point source into a river can be measured by the amount of oxygen in the water. The more oxygen that is in the water the more life that the river or stream and sustain. Dissolved oxygen levels are often measured to determine the quality of the water in different location. Another measurement of water quality is the biochemical oxygen demand. This measures the amount of oxygen by determining the amount of dissolved oxygen consumed by aquatic microorganisms.
The largest form of pollution comes from sediment. While sediment is necessary for the fertility of the river bed, we spend millions of dollars removing sediment from our drinking water. Take out the human equation and the sediment would not need to be removed and could continue to form deltas, but needed clean drinking water is what ranks sediment as the highest pollutant.
Chapter 7
Global Food and Nutrition
With all of the commercials on television and the ads for adopting starving children, it is hard to imagine that our food production has gone up dramatically as a planet. We produce so much food, that we now use corn and sugar as alternative forms of fuel. It is cheaper than ever to produce food. In fact the cost of food is only a quarter of what it was in the 1970’s.
Fifty years ago global starvation was a persistent global issue. While some of these circumstances have changed and hunger has dropped dramatically, others have not changed at all. When you look at the numbers it seems like there should be more than enough food to go around. While the human population increases by 1.7% a year, food production increases by 2.2%. China and India (both countries with the largest masses of people) have increased their protein consumption exponentially.
But global hunger is still around. One out of every eight people is hungry. While 95% percent of the hungry are in developing countries, the rest are close to home. Food security is the idea that humans can obtain enough healthy food every day to survive. Many do not have food security. In countries like the United States and other western European countries, lack of jobs and social services create vicious cycle of poverty and hunger.
Famines are another huge cause of starvation and death. Famines are the direct result of political instability and war. For many developing countries it is cheaper for their governments to produce mass commercial crops than to collect from the peasant farmers. These farmers are driven off their land into the already overcrowded cities and expected to survive. Without corrupt governments, farmers could survive years of drought and natural disasters. But these governments create environments that make it impossible for them to overcome these disasters and so famine begins.
How Much Food Is Enough Food?
It is important for every human life to have a balanced diet. We all need essential vitamins and minerals to survive. Malnourishment is the result of the lack of a healthy diet. Without protein and calories young children are skinny and shriveled and do not have resistance to disease and infections. Vitamin A deficiencies are responsible for hundreds of thousands of people going blind. Lack of folic acid can cause neurological problems in babies, and lack of iodine can severe swelling of the thyroid gland.
In areas that have large population of impoverished people the diet is made up primarily of starchy foods such as rice and maize, which lacks the nutrients needed for a healthy diet.
Overeating is now almost as big of a problem as starvation. In today’s world there are more overweight people than underweight. Obesity is not just an “American” problem but has spread across the world. Issues like heart attacks and diabetes are now global problems. The United States, Europe, and China claim that 64% of their population is overweight. Nearly half! With this staggering number comes an even more shocking onslaught of diseases and complications. In the United States 400,000 people a year die from illnesses caused by obesity.
Unfortunately, just because there is more food in the world, does not mean that hunger is reducing. In an effort to control the overproduction of food in wealthy countries, much of it is sent to developing countries. However, if falls in the hands of politically corrupt people and war lords who control the distribution of this food. In America we throw away almost half of our prepared food. However, if we shift our way of eating to vegetable filled diets instead of meat filled diets, the amount of waste would decrease and the farming industries would increase.
What do we Eat?
There are so many edible plants and animals on the planet, but our diets only contain a handful of these! In the United States we consume (directly and indirectly) more corn and soybeans than any other product.
However, most of the corn and soybean that we eat is not in its natural form. These products are refined and put into almost everything we eat. They serve as fillers and artificial sweeteners and other products. (I challenge you to look at the back of any package at the store and you are almost always going to find a soy or corn based ingredient). They are also in the grain that is fed to the livestock that we will later eat.
Sadly our production of this greatly desired meat can and does cause a great amount of pollution to our environment. The animal waste can contain harmful contaminates that then seep into the soil and pollute ground water. Also, in order to allow these animals to graze, forests and other ecosystems must be cleared out to make room.
Precious Soil
Soil is much more complex that what meets the eye. To anyone of us, we could look at soil as no more than a pile of dirt. But soil is an essential combination of sand, gravel, silts, clay, dead organic material and faun, and flora that give nutrients to plant life.
There are several layers or soil horizons. Most of the soil we use and need is from the A horizon, or commonly known as topsoil. Topsoil has the organic material needed for many of our plants to gather root and begin producing. O is the level right above the topsoil which is mostly composed decaying leaves and other debris. Below the topsoil is E or the zone of leaching which is made up of dissolved material making its way deep into the earth. Below that is the B level or subsoil. Subsoil contains a lot of the mineral nutrients like iron and aluminum as well as clay. The next layer is C and has the weathered parent material that is mostly decomposed rock fragments. The final and deepest layer of soil is the Parent material which is made up of sand, silt and bedrock.
The health of the soil is dependent on the climate above it and the ground below it. Too much rain will wash away the needed organic material and too little will cause the fauna to die.
Chapter 11
Energetic Planet
To coin our planet as living is an understatement. Every corner of the world sees change every minute of every day. From the things that we control, like planting a tree or building a house, to the things we cannot control like life and death. We watch the wind come and blow away leaves that have died, and then watch spring give birth to new leaves and flowers. Every part of this is a miracle, but the miracle begins far beneath our feet.
The center of our planet is composed of the core which is a dense hot mass of metal (iron). While the center of the core is solid, the farther away from the center you get the more fluid the metal becomes. The next layer is the mantle, which is hot but pliable rock. The next layer of our planet is the crust, which is cool and light weight. In some areas of the plant (the bed of the ocean) the crust is thin, and in other areas the crust is thicker and denser. Thick or thin, the crust shifts and moves on the mantle beneath it.
The tectonic plates are pieces of the crust that currents in the mantle broke apart. These plates are always shifting and bumping into each other. When these plates grind up against each other they result in massive earthquakes which change the face of the earth. Mountains rise as the plates push together and magma seeps through where the plates separate forming underwater mountain rages that dwarf any seen on the surface.
Minerals and Rocks
It is easy to overlook the importance of minerals and rocks let alone the difference between the two. You would be hard pressed to find someone on the street that could tell you what the difference is. While both play vital roles in our economy and our environment, they are different.
Minerals are naturally occurring and inorganic solids with a specific chemical composition and internal crystal structure. Simply, copper in its mineral state found in the United States and in Mexico will have the same chemical structure. However, once copper has gone through the purification process it is no longer crystalline and so no longer a mineral. Minerals can range in size from microscopic to tree size.
Adversely, a rock is a solid cohesive aggregate of one or more minerals mixed together and bound firmly in a solid mass. For example, granite is a rock made up of quarts, feldspar and mica crystals (minerals).
Geology and Mineralogy
Minerals are essential to our daily lives. Everything we do and everything we have either contains minerals or required minerals to develop it. Because of this, the need for minerals has become a vital part of our economy and trade agreements. Because our planet is so diverse, every region has its own mineral makeup. This map show s the diversity of our planets metals.
We need aluminum to package food, to build transportation and to create electronics. We need copper for the electric industries and lead for batteries and paid. We iron and nickel to produce steel and gold for money, medical uses, and aerospace engineering. If anyone of these metals were missing, we would be missing a large piece of the puzzle. As we have grown to rely on these metals, we need to rely on good standing trade relationships with countries that are abundant in these materials.
We also find value and need in many non metal minerals. From gemstones to soil, limestone and salt, we need all of them. The high silica sand is used to make glass. Other sand and gravel are used to make brick and concrete. Limestone is used in buildings and plaster. Gemstones hold wealth and beauty (and have caused their fair share of global headaches with crime and slave labor).
Resource Extraction and It’s Effects
While we have found great value and necessity in minerals, it has come at a high cost. The extraction of these minerals causes large amounts of damage to our planet. The EPA lists more than 100 toxic air pollutants that are released from mines and wells in the United States every year. 11,000 tons of sulfur dioxide is released into the air from non metal mining. Acidic mine runoff destroys waterbeds and ecosystems.
In order for mines to extract gold and other metals from sulfide ores tons of ore must be crushed and washed. This produces water that contains sulfuric acid , arsenic and heavy metals which makes the water useless for any other purpose.
There are a few different type of mines that are used to extract geologic material. The most common are open-pit mining, strip-mining, and underground mining. Panning gold and blasting away hillsides were and are common methods of extracting gold, however this chokes rivers with sediment and makes it difficult to filter out clean water. Other mines that pump toxic materials back into the water supply cause damage that may be irreversible. Open pit mines are used to extract large beds of metal ores and other minerals. The problem open pit mining causes is the ground water contamination. As rain and melted snow seeps into the aquifer, so do the harmful heavy metals, contaminating the water supply. These toxic lakes put wildlife and watersheds at risk.
It is not just the mining process that poses pollution issues to our planet, but also the processing of the product mined. In order to get the metals out of the mined ore, it must be heated or checmical solvents can be used. Both options produce high amounts of toxic materials that are released into the air. Smelting (heating ore to release metals) released harmful toxins into the air that can settle in the surrounding vegetation and destroy anything in its path.
Conserving Geological Resources
It is true that most minerals can regenerate on their own deep within the earth. However, this process can take millions of years and we are depleting the resources at rate so fast that they will be long gone before we see the effect of regeneration. Instead we must find a way to use what we have already extracted from the earth and slow our future extraction.
Recycling is a very positive option. It takes less energy to recycle a mineral than it does to extract it. For example, the soda can that we buy from the store can come home, be emptied, turned into a recycling plant and then back on the shelf in another form in about two months! Today two thirds of our soda cans in the United States are recycled (this is a drastic change to only 15% being made from recycled material 20 years ago). Other commonly recycled metals are gold, copper, and steel.
There is also the option of new materials and new technologies replacing the mining of materials. For example, the use of plastic piping has decreased the need for lead and copper pipes. Also fiber optic technology is replacing the need for copper wires. Steel (which as long been a fabric or our industrial nation) is being replaced in automobiles with lighter products such as alloys made up of steel, titanium and vanadium. Technology is showing us that there are better ways to get the same job done without harming our planet.
Geologic Hazards
Long before humans walked the earth and for millions of years to come, nature will give us natural disasters that come in the form of volcanoes, floods, landslides, tsunamis, and tornados. Despite their inevitable occurrence, they are devastating to human life. In 2010 Haiti was rocked with a huge earth quake, but it wasn’t the worst the world has seen. In 2004 Indonesia saw an earthquake and tsunami that killed more than 230, 000 people.
Earthquakes are caused by sudden movements in the earth’s crust along fault lines. When the plates slide past one another they rub together causing an shuddering effect or earthquake. The epicenter is the point of the fault line that the movement occurred on. Earthquakes can destroy cities and dislocate landscapes.
Volcanoes and underwater magma vents are what formed most of the earth’s crust. Most of the earth’s fertile soils are weathered volcanic material. Despite their help in forming most of our planet’s surface, they are deadly and devastating to human populations. One of the biggest and most historic volcanic eruptions occurred in Mount Vesuvius in southern Italy. It buried the cities of Herculaneum and Pompeii in A.D. 79. The mountain gave warning of its impending eruption, but many citizens stayed. Thousands were killed by the hot and toxic gases that erupted with ash. Mount Vesuvius still erupts occasionally.
Floods are also part of the earth’s natural process, but cause devastating damage to human life. Like any of the other natural disasters, they do not take into account human impact. Rivers create floodplains that are vast pieces of land that are fertile and provide easy access to the river. It is for those reasons that humans choose to settle there. Floodplains can appear to be deceivingly safe for years at a time, but will eventually flood and destroy everything in its path. Floods claim the largest amount of human lives and damage. A flood in China in 1937 killed 3.7 million people which made it the deadliest natural disaster recorded. Despite efforts to control flooding, building a levy upstream simply causes a bigger problem downstream. Of all of the natural disasters, flooding is one that can be controlled. Rivers and streams can be diverted, dams can be built and people can avoid building in areas that are floodplains.
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