Core case studies APES

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Disappearing Amphibians

Amphibians are animals like frogs, toads and salamanders. They were the earliest animals to evolve to live on land. They were able to adjust to the environmental changes brought by the past, but now in this anthropogenic controlled world, the amphibian world is changing rapidly. An amphibian lives not only in water, but also on land, but now many amphibious species are having difficulty in the past few decades. This is mainly from the overuse of pesticides which get washed downstream from rain and pollute waterways. Since the 1980s, hundreds of amphibian species declined or vanished. According to the IUCN about 33% of all known amphibian species are threatened with extinction, and more than 40% of all known amphibian species are declining. Amphibians are important because they serve as biological indicators for changes in the environment such as habitat loss, air and water pollution, UV radiation and climate change. The growing threat of their survival indicates that environmental conditions are deteriorating. Second, many adult amphibians play important ecological roles because they kill many insects and extinction of amphibians could lead to a chain reaction in its ecosystem. Finally, amphibians are storehouses of genetic material and are very helpful in creating pharmaceutical products.

Exxon Valdez

An oil tanker crashed into a reef in Prince William Sound on March 24, 1989. The oil tanker was bound for a long beach. It spilled 260,000 to 750,000 barrels of oil. It is considered to be one of the worst environmental disasters caused by humans. It occurred in a remote location with limited access which made it difficult to respond to the spill. Clean up efforts tried to clean the 11,000 sq miles of ocean and 1,300 miles of coastline yet it was hampered greatly because people were not prepared. There was around 100,000-250,000 seabird, at least 2,800 sea otters, 247 bald eagles and 22 killer whales. In response to this the US congress passed the Oil Pollution Act in 1990 and forced oil tankers to have double-hulled ships.

Burmese Pythons in the Everglades

Burmese pythons like African pythons have been accidentally introduced in Everglades national park in the US state of Florida. About a million of these snakes have been sold as pets. After learning these reptiles do not make good pets, many owners dumped them into the wetlands of the everglades (BAD IDEA). The Burmese python can live 20-25 years growing as long as 5 meters. These pythons are hard to find and hard to kill with no natural predator in the area. They also reproduce massively and kill many of its prey. The predation of these snakes has shifted the complex food web in the everglades and many fear that the pythons will reach other wetlands.

Coral Reefs (PG 169)

Coral reefs are a very diverse aquatic ecosystem. They form in clear, warm coastal waters and in tropical areas. They are the most productive ecosystem in the ocean. Coral Reefs are formed by massive colonies of tiny animals called polys and they slowly build reefs by secreting a protective crust of limestone. Although they only occupy .2% of the ocean floor, they provide important ecosystem services. They act as a natural barrier for 15% of the worlds coastlines from erosion. They have provide habitats for 1/4 of all marine organisms. They also produce 1/10 of all fish catch globally. Since the 1950s around half of the shallow coral reefs have been degraded and are being destroyed by trawler boats or by coral bleaching. Ocean acidification and heat can also destroy coral reefs.

DDT and Rachel Carson

DDT is a pesticide that was widely used from 1939 to 1973, when it was found to be toxic to humans, wildlife and ecosystems. It was banned in the US in 1973 and the person who raised awareness was Rachel Carson with her book Silent Spring (Published in 1962). DDT kills insects really well, but the risks outweigh the benefits. In countries with malaria though, DDT is still widely used because it was a cheap solution to killing mosquitoes with malaria because there aren't any other safe and cheap pesticides that can be widely used in those countries. DDT resulted in the decline of many bird species through the process of bio magnification like the bald eagle. Even though DDT was banned in 1973, it still persists in the environment today in our country and has even been found in the groundwater supplies.

Testing planetary boundaries (PG 72)

For the past 10000 years, humanity has been living in the Holocene era, which was a period of stable climate and environmental conditions which followed a long ice age. The stability allowed the human population to grow, develop agriculture, and, to flourish within societies. This led to us taking a large portion of the earth's resources and now after the start of the industrial revolution, humanity has been living in an Anthropocene era, where humanity has become large factors in determining earth's climate through their ecological impact and carbon footprint. In 2009, 28 well-known scientists led by Johan Rockstrom created 9 planetary boundaries or tipping points. In 2012, a tenth was suggested by Steve Running. These scientists say that if we go over the tipping points, we would create an irreversible chain reaction and create massive ecological changes. The limits of these values are uncertain and we are still uncertain about what the effects would be on human health and earth's life support systems.

Tuy Sereivathana (PG 22)

He was someone who protects elephants from poaching and farming. People in Africa killed elephants to protect their crops or villages. He directs a Cambodian elephant conservation effort. He wants to teach farmers better techniques to defend their crops instead of killing them. Examples include using low voltage electric fencing or not growing watermelons but growing chiles and eggplants instead. Elephants had to find food on farmland because the lush forests that were throughout the country were cut because of population growth.

Where have all the honeybees gone? (PG 190)

Honeybees spend their days collecting nectar and pollen that they take back to their hive. They feed their protein-rich pollen to flowers and pollinate the flowers. It enables flowering plants to produce seeds and fruit. Bees pollinate many important food crops such as almonds. Globally 1/3 of our food supply is from pollinated plants and 80% are from European honeybees. The overuse of this one type of bee species has lowered biodiversity and made bee species more vulnerable from this industrialized pollination system. If this type of honeybee declines it could lead to a large global food crisis, but if there were many species to pollinate crops and not just one, pollinators and our food supply would be less vulnerable. There was a 30% drop of honeybee populations in the united states and in Europe, large portions of bees disappeared during the winter. This phenomenon is called colony collapse disorder. In each year since 2006, around 30-50% of the honeybee colonies suffered from it, yet we know very little about this disorder. This and other anthropogenic sources (Habitat loss and climate change) will greatly affect the honeybee population and in turn, many plants that need pollination.

Hurricane Katrina

Hurricane Katrina was one of the deadliest hurricanes in US history and one of the costliest. At least 1836 people died in the hurricane and the resulting floods and total property damage is estimated at 81 billion dollars. The category 3 storm made landfall on August 29, 2005 in SE Louisiana. The area hit hardest was New Orleans where their levee system failed flooding 80% of the city. This eroded several beaches substantially and several barrier islands were moved closer to the coastline. The chandeleur islands were completely destroyed. Over 20% of local marshlands were covered with water. A wildlife refuge also lost half of its land which was a vital habitat for several sea turtle species. The hurricane wouldn't be as bad if it weren't for the marshlands which protected flooding being turned into farmland.

Ocean Gyres

In 1997, ocean research Charles Moore accidentally discovered two gigantic, slowly rotating masses of small pieces of plastic and other wastes in the middle of the North Pacific Ocean near the Hawaiian Islands. They are trapped by a vortex of rotating ocean currents. Roughly 80% of the wastes come from the land like washed off of beaches or out of storm drains. Most of the rest of the waste is dumped into the ocean from cargo and cruise ships. The North Pacific garbage patch is estimated by some scientists to occupy an area at least the size of text. Research shows that these tiny plastic particles can be harmful to marine mammals and to some sea birds with plastic getting into their body and poisoning them. Since the animals cannot digest plastic, it can cause them to die from starvation and choking as well. Fish that feed on plankton in that area contain PCBs, DDT, BPA and other chemicals. They can bioaccumulate and then harm the fish or whatever eats the fish.

Invansion of the Asian Carp

In the great lakes, an invasive predator that threatens the great lakes is the Asian carp. It is the most recent threats and was imported in during the 1970s. They were imported in to remove suspended matter and algae from their aquaculture ponds, yet heavy flooding caused many of these ponds to overflow releasing carp into the Mississippi river and now in lake Michigan. They can eat a lot and disrupt food webs really quickly. They even jump out of the water sometimes and many boaters have even been hit by jumping carp. These fish have no natural predators making them an invasive species.

Insects play a vital role in the world (PG 80)

Insects play a vital role in the world even if we think of them as pests because they compete with food or spread diseases. Firstly, insects pollinate plants which is a vital ecosystem service that allows flowering plants to reproduce through pollen grains that are transferred from the flower of one plant to a receptive flower of another plant. Also, some insects eat other insects that are considered pests. It is a free pest control service that is more Eco-friendly than pesticides and is used widely in IPM. Insects also play a key role in loosening and aerating topsoils like earthworms or the dung beetle. Insects reproduce quickly as well so they have a good ability to evolve very rapidly to environmental changes. This scientific study of insects and what they do is called entomology. Environmental threats from the Anthropocene era like habitat destruction, pollution, and topsoil degradation are all threatening many insect populations. One very important species that is being affected is the honeybee which is a vital pollinator.

Invasion of the Lionfish

Invasive. Native to indo-pacific. Has venomous spiky fin rays. Consumes small fish, invertebrates, and mollusks in large amounts. Few natural predators. Established in East Coast of US and Caribbean. First introduced off Florida Coast when Hurricane Andrew destroyed an aquarium, releasing fish into open waters. Directly affect food web relationship. Leads to reef deterioration. Many 'derbys' held to eradicate species. Attempts to sell on food market, if cleaned correctly the naturally venomous fish is safe to eat.

Hetch Hetchy Dam

It was a dam in a valley within Yosemite National Park to provide water for the city of San Francisco. The valley was permanently flooded when it was dammed up and now provides hydroelectric power as well. Between 1908 and 1913, Congress debated whether to make a water resource available or preserve a wilderness when the growing city of San Francisco, California proposed building a dam in the Hetch Hetchy Valley to provide a steady water supply. The Hetch Hetchy Valley was within Yosemite National Park and protected by the federal government, leaving it up to Congress to decide the valley's fate. National opinion divided between giving San Francisco the right to dam the valley and preserving the valley from development. In the end, Congress passed legislation that enabled the creation of a dam in the Hetch Hetchy Valley. President Woodrow Wilson signed the bill into law on December 19, 1913. Although the preservationists lost this battle, the damming of the Hetch Hetchy Valley raised public awareness about the importance of preserving nature, and helped justify the creation of the National Park Service in 1916. https://www.archives.gov/legislative/features/hetch-hetchy

The Great Jellyfish invasion

Jellyfish are not fish, it has no brain but a collection of nerves. It stings its prey and draws food into its mouth. They usually stay in clusters or "Blooms" of jellyfish. The sting of jellyfish kills dozens of people and they cause beach closings having an economic impact of tourism. They can also disrupt fishing by clogging nets and they can close down power plants by clogging their cooling water intakes. Jellyfish are on the rise due to the fact that we hunt or kill the Jellyfish's predators including sea turtle. Excessive amounts of fertilizer also help jellyfish grow because it is practically a feeding ground in eutrophication. Warmer waters also creates more jellyfish so global warming won't help. The growth of Jellyfish populations will threaten aquatic ecosystems.

Kudzu Invasion

Kudzu is a bamboo-like plant that was intentionally introduced to the US from Asia in 1876 as a decoration. It also was used to cover soil and prevent soil erosion. Although it had its uses, it was a fast growing and hard to kill plant that deprived other plants of CO2 and Water practically killing them. It also has the ability to fix nitrogen from the atmosphere practically allowing it to create its own fertilizer. It can take root in practically any soil letting it out compete in most ecosystems. Kudzu can alter ecosystems and reduce its biodiversity. Grazing with kudzu plants helped reduce and control kudzu population during growing seasons. It can also grow almost anywhere damaging structures and it costs the US government millions of dollars a year to control. Now it is listed as a federal noxious weed.

Deepwater Horizon

On April 20, 2020, the world learned a harsh lesson about the environmental impacts of deep-sea drilling. Deepwater Horizon, an oil rig, exploded. The accident occurred in the Gulf of Mexico, 64 kilometers off of the Louisiana coast. 3 months after this accident, 4.9 million barrels of crude oil were released into the open ocean. It contaminated vital coastal marshes, mangroves, sea-grass beds and other aquatic ecosystems. It killed over 6,000 sea birds and 600 turtles. The spill also disrupted the livelihood of fishers.

Passenger Pigeon

Passenger Pigeons were once the most common bird in America. They used to nest in huge colonies, yet they were overhunted and their habitats were destroyed by population growth and urban development. Their flocks used to number in the billions yet they were able to become extinct. They were seen as disposable and no one realized they could become extinct. In 1914 at the Cincinnati zoo, the last passenger pigeon died.

Testing water for pollutants (PG 548)

Scientists use a variety of methods to measure the number of different pollutants in the water. Firstly, they test the water for the presence of infectious agents like coliform bacteria which is a sign of animal waste in the water. That leads to other bacteria that may have disease-causing agents. For safe drinking water, a 100-milliliter sample of water must contain no colonies of coliform bacteria. To be considered safe for swimming, water samples should not have more than 200 colonies of coliform bacteria. Another indicator of water quality is the dissolved oxygen content. Excessive amounts of oxygen demanding wastes would lower the DO content of water. The more DO in water, the higher the quality of water. (Gulf of Mexico dead zone is suffocated of DO) Next scientists can use chemical analysis to determine the presence and concentrations of specific organic chemicals in polluted water. Indicator species also help see if the water is polluted such as cattails and bottom trawlers. People can also measure the turbidity of the water to measure the amount of bacteria or sediment in the water.

Sea Turtles

Sea turtles are now in danger of becoming extinct mostly because of human activities from the past 100 years. Sea turtles that hatch and are confused by the lights and sometimes don't go towards the ocean, but instead towards those lights. Also they are being killed by the plastics in the oceans. They are vital because they help control the growing jellyfish populations. Trawler fishing has destroyed many of the coral gardens that served as the turtles feeding grounds and they become entangled and drown in fishing nets/lines. Pollution also is another threat to turtles. Sea turtles eat plastic mistaking it for jellyfish and they can choke to death trying to eat the plastic. Tourists on the beach and vehicles also can trample over their nests and destroy their habitats. Sea levels rising will also flood and destroy many turtle's nesting grounds greatly lowering the amount of nesting grounds.

Saving Sharks

Sharks are a very ancient species. They are a keystone species that play crucial roles in keeping their ecosystems functioning. They help prevent the ocean from being filled with dead animals and also keep populations of other populations from booming similar to the gray wolves of Yosemite. The media portrays sharks as evil, but the cases of shark attacks are very rare. For every death or injury from a shark, humans kill 1.2 million sharks. As many as 73 million sharks are caught each year for their valuable fins and then throw them back into the water alive. The sharks end up drowning or bleeding to death because they can not swim. Sharks are also killed for their livers, meat, hides and, jaws. Each year, an estimated 50 million sharks die when fishing lines and nets trap them. Even when there is no evidence that shark fins can heal anything, people still use them in pharmaceutical products. Eating sharks can also be dangerous because they can be contaminated with high levels of toxins and mercury. According to a 2009 IUCN study, 32% of the world's open-ocean shark species are threatened with extinction. They are a very vulnerable species because they grow very slowly and provide a valuable ecosystem service.

Jane Goodall (PG 33)

She is a researcher of chimps. Through her studies she found that chimps could make and use tools (ex: sticks to eat termites). She then established a nonprofit that preserves the species of apes from poaching and hunting similar to what CITES does. Furthermore, in her research she found that chimps can do simple arithmetic, play computer games, develop relationships and protect each other. This person fights for animal rights and now educates youth about this.

Chesapeake Bay (Estuary in trouble)

Since the 1960s, the Chesapeake Bay has been in serious trouble from water pollution. This was from population growth mainly. It contains a huge drainage basin so it picks up the wastes and fertilizers from farms. Point sources include sewage plants and industrial plants. Non point sources include fertilizers and animal wastes. 1 century ago, oysters were so abundant here that they filtered and cleaned all of Chesapeake's water in 3 days acting as a keystone species. The oyster population has been reduced now making the filtration process take a whole year and the keystone role of this species severely weakened. In 1983, the US created the Chesapeake Bay Program which tried to reduce pollution into the bay. In 2008, the 25 years of work didn't amount to much costing 6 billion dollars. This was due to population growth and a lack of cooperation with state government and a lack of funding. Luckily, it was found in 2011 that the DO zones were decreasing each year.

Everglades Restoration

South Florida's everglades used to be a 100 kilometer wide sheet of water flowing slowly. It was a river of grass that trickled south that was a large wetland. To preserve the wilderness in 1947 the US government established it as a national park which contains a part of the remaining national park. Also in the north the US army corps of engineers transformed the wandering 166 milometer long Kissimmee river into a straight 84 kilometer canal which further drained the wetlands. This led to more flood protection and water supply but also is destroying the everglades. The government tried to restore this by curving the Kissimmee river and removing 400 kilometers of canals and levees that blocked waterflow to the everglades.

Colarado River Study (PG 318)

The Colorado river is a major river that flows in southwest US. It flows 2,300 kilometres through many states and is a large water supply, yet it is overused. During the past 50 years damming projects have plagued this river, yet it helped control the river greatly. (Dams protect against floods, used for water supply or irrigation or are used for hydroelectric power). The water used in this river produced about 15% of the nation's crops and livestock and it also supplies water to some of the driest cities like Las Vegas and LA. The massive state of California also relies on this river and without it, the state would practically become a desert in the south without the north supplying it water. There is too much water being withdrawn and very little reaches the sea or its estuary in Mexico that was once prolific. There was increased reliance on this water source recently because of a drought in the area.

Dust Bowl

The Dust Bowl was a period of severe drought that caused the central Midwest prairie to turn to dust; eroded farm soil, making it impossible to plant crops; and forced many farms out of business. The DB caused families to go out west in search of work. It destroyed the topsoil from overplowing and the dried topsoil was picked up by the wind ravaging the great plains area in dirt storms. The soil was over farmed showing environmentalists the need to have cover crops like legumes in the soil.

The ivory billed woodpecker

The Ivory-billed Woodpecker was never a common bird, since it depended upon enormous, unbroken expanses of southern swamps providing the space and food it needed to thrive. Once its habitat began to disappear due to uncontrolled logging, the woodpecker became increasingly scarce. It was frequently shot by hunters and collectors, which likely contributed to its disappearance. The ivory-billed woodpecker was listed as an endangered species on March 11, 1967 by the United States Fish and Wildlife Service. The ivory-billed woodpecker has been assessed as critically endangered by the International Union for Conservation of Nature and Natural Resources.

Invasion of the fire ants

The Red Imported Fire Ant (RIFA, for short) is a major economic pest in the southeastern United States. It originates in lowland areas of South America, primarily Brazil and Argentina. Since its first documented interception in 1984 at a border station in California, periodic outbreaks have occurred in several counties. In the past, these outbreaks were limited to private properties amenable to rapid eradication efforts. A state-wide eradication effort began in 1999 and ended in 2003. Some localized eradication efforts are still continuing by Vector Control Districts (in the Coachella Valley and Orange County) and Agricultural Commissioner's offices (Los Angeles and San Diego counties) which have continued treatments aimed at controlling the ants. Eradication efforts by the California Department of Food and Agriculture also continue in the Central Valley.

Lead in the water of Flint, MI

The city was being taken off of a water supply, so they decided to switch the water supply to the flint river (Treated water, but it was slightly more acidic). When they switched the water to this clean water source, the lead pipes that carried the water started to degrade because they were old and not kept together. Lead was carried from their pipes into their homes creating the crisis known today. There are still problems even today with the blame being tossed to both sides.

Pollution of the Great Lakes (PG 552)

The five interconnected great lakes of north America contain around 95% of the fresh surface water in the US and 1/5 of the world's fresh surface water. At least 38 million people in the US and canada get their drinking water from these lakes, yet they are vulnerable to pollution. Barely any of the water in these lakes actually flow out towards the Atlantic Ocean making them vulnerable to pollution. It takes up to 100 years for pollutants to be flushed out to sea and in the 1960s many areas of the Great Lakes suffered from eutrophication from industrial wastes. To counteract the pollution Canada and America signed the Great Lakes Water Quality Agreement in 1972. They agreed to spend more than 20 billion to maintain and restore the chemical, physical and biological integrity of the great lakes. Now algal blooms have decreased and the waters have became cleaner. It is an environmental success story.

Gray Wolves in Yellowstone

The gray wolves used to roam the US in large numbers, but as the American Population grew they declined and moved west. In 1974 the gray wolf was designated an endangered species. We took them out of Yellowstone and hunted them nearly to extinction, yet we didn't realize they were a keystone species that helped regulate the entire ecosystem. Without them, herbivore populations rose greatly and as a result the vegetation along rivers was eaten and the banks eroded as a result expanding the river and slowing the flow. It also lowered the population of scavengers who needed the gray wolves to kill their food. Officials noticed this and in 1995, they reintroduced Gray Wolves and as a result the herbivores left the water areas for the mountains restoring the vegetation and making it so there would be less soil erosion and a faster flowing more narrow river. This also led to an increase of beaver populations and it helped increase the vegetation in the surrounding areas of the rivers. Because of the success of the reintroduction, gray wolves were downgraded to threatened status in 2003.

Gold Mining

The mining waste to create a newlyweds couples wedding rings is roughly enough mining waste to equal 3 mid sized cars. The waste is usually left piled near the mine site and can pollute the air and nearby water supplies. In 2012, the five top gold producing countries were China, Australia, US, South Africa and Russia. Around 90% of the world's gold mines, gold is extracted with the use of a solution of highly toxic cyanide salts being sprayed to piles of crushed rocks. The solution reacts with the gold and then drains off the other rocks, pulling some gold and settling it into ponds. After extracting gold, instead of cleaning up the site, the companies declare bankruptcy or they pay the fines instead of cleaning up the site. They leave the cyanide-laden water in ponds at the sites which can seep into aquifers. Poverty stricken miners has also cleared forests in search for gold in the Amazons which is illegal and has led to deforestation. There are other solutions to extract gold, yet the industry is fixated with this process making consumers need to say something to fix this unsustainable practice.

Gulf of Mexico's Dead Zone

The mississippi river basin lies within 31 states and almost contains two-thirds of continental U.S land area. With it containing more than half of American croplands, the excess fertilizer from these croplands travel downstream and create eutrophication in the Gulf of Mexico. This happens each spring and the DO content of this area lowers greatly, killing off most life. Faster fish are able to swim away, yet bottom-dwellers become suffocated under the little DO content and algal blooms. This dead zone is one of the 400 dead zones in the world, all were created anthropogenically. Overfertilization causes Eutrophication.

Aral Sea

The shrinkage of the Aral sea is the result of a large scale freshwater transfer project implemented by the Soviet Union to turn one of the driest parts of central Asia into farmland. Enormous amounts of water has been diverted from the two rivers that usually supply the Aral sea to create a massive irrigation project for rice and cotton. The irrigation canal stretches around 800 miles. This large scale diversion project has caused a drought and high evaporation rates due to a hot dry climate. The sea's salinity has risen seven fold and the average level of its water dropped by an amount equal to the height of a six-story building. It has lost 90% of its volume in water and the rivers have almost became mere trickles as a result of the irrigation projects. About 85% of the wetlands surrounding it have been eliminated and most fish species are extinct. It also ruined the local fishing industry of over 60,000 people. Now all that remains from those once vast cities is a salty desert. Winds pick up the sand and salty dust and blow it onto fields as far as 500 kilometers away killing crops and wildlife.

Organisms are invisible to us (PG 58)

There are trillions of microorganism that can be found They are called microbes. These organisms can provide vital services to animals such as digestion and decomposition. The more diverse bacteria in your digestive system the healthier a person is because they are able to digest more and it usually means they have a balanced diet. Phytoplankton also provides oxygen and provide food for aquatic ecosystems. Some genetic engineers have modified microorganisms to clean up pollution and some toxins in water and soil.

Rainforests are disappearing (PG 52)

These forests are disappearing at a rapid rate. They provide a vital role to life and provide a diverse ecosystem. They have high temperatures, high rainfall and high humidity. They only cover around 2% of the earth, but they have over half of the world's land species. Half of the forests were destroyed by desertification, overgrazing, unsustainable farming practices and urban development. Forests are vital for keeping the biodiversity on the earth and without as many forests it accelerates climate change and can change regional weather patterns.

Southern Sea Otter

This animal lives in giant kelp forests and in shallow waters along parts of the pacific coasts. They act as a keystone species by eating sea urchins and clams that would otherwise overpopulate and destroy the kelp forests. Sea otters are fast and agile swimmers looking for shellfish and sea urchins. By the 1900s because they were overhunted they were as low as 50 left in 1938, yet the population rebounded to 2,800 in 2012. They were endangered for sometime due to overhunting for their rich pelt. They are important to protect because they are intelligent animals that generate tourist revenues and they are a keystone species.

Hubbard brook forest experiment (PG 30,47)

This experiment was led by Herbert Bormann in 1971. It was a controlled experiment to see the loss of nutrients on a mountain from water. On one part of the experiment they created a dam to catch the water from a verdant area of land and another dam to catch the water from a deforested side of a hill. The deforested side had more water travelling through, but the nutrients in the deforested soil were gone and little to no vegetation could go there due to topsoil erosion. The deforested valley lost vital nutrients while the forested valley kept its nutrients because of plant roots.

Three Gorges Damn

This is the world's largest most controversial dam. It was completed in 2009 on the Yangtze River in China. The dam is being used to provide hydroelectric power throughout the country. Sadly, the construction displaced 1.2 million people as their towns flooded. Also, it flooded priceless archaeological sites. Mining and waste sites were also flooded so the water had a chance to be polluted. There is less downstream in the water. Downstream helps flush out pollutants in water. Sediment can also build up over time slowing or blocking floodgates. Croplands and forests has been lost upstream and downstream there are fewer nutrients being deposited in the ecosystem. Next, there is more saltwater intrusion into china's drinking supplies because of this.

Cuyahoga River Fire

This river is located in NE Ohio and is most famous for being the river that caught on fire. There have been 13 reported fires on the river because it is one of the countries most polluted river. This first fire was in 1868 and the last one was on June 1969. Someone caught this on photo and it spurred a movement to clean out the polluted water and led to the Clean water Act and the Great Lakes Water Quality Agreement. It also led to the creation of the federal Environmental Protection Agency.

Biosphere 2 (PG 684)

This was a 1991 study where eight scientists were sealed in Biosphere 2, a 200 million dollar glass and steel enclosure designed to be self-sustaining and a life-support system copying the Earth's nutrient cycles. This sealed had interconnected domes in Tucson, Arizona. It contained artificial ecosystems like tropical rain forests, savannas and, deserts. It also contained practically every aquatic ecosystem. It was supposed to mimic the earth's natural systems. The 8 scientists were supposed to live and produce their own food in that area by themselves through chemical cycling. From the beginning, there were many problems that were unanticipated. First off the level of oxygen declined because of soil organisms converting it to CO2. Tropical birds ended up dying in the first freeze as well. Ant species snuck into the enclosure and killed off most of the system's original species. Before the 2 year period was over, all plant-pollinating insects were extinct dooming most plant speices. Despite these many problems, the facility waste and wastewater were recycled with much hard work and they were able to produce 80% of their food supply despite rampant weed growths spurred from the high CO2 levels. The scientists sadly suffered from hunger and weight loss. In the end, the 200 million dollar mission failed to maintain and create a life-support system for eight people. It shows how humanity still knows very little about how to create and control life support systems.

Santa Barbara Oil Spill

This was a spill between Jan and Feb 1969 in the Santa Barbara channel. It was the largest oil spill in US waters until the Exxon Valdez spill of 1989. The source of the spill was a blowout on Union Oil Platform A. The well was capped within minutes but the rupture of the ocean floor allowed 80,000 to 100,000 barrels of crude oil to spill into the channel and eventually drift onto beaches from Goleta to Ventura and four Channel Islands. This helped spur the creation of the EPA as well as policies like the CEQA or California Environmental quality act.

Costa Rica (PG 218)

Tropical forests once completely covered costa rica, but deforestation and overgrazing by powerful ranching families cleared much of the forest. Despite much forest loss, Costa Rica has a massive amount of biodiversity with around 500,000 species. A single park in Costa Rica has more species of birds than NA. Many exotic animals live in this ecosystem. The biodiversity here is so large due to the mountainous terrain and the tropical location. Also the government began strong conservation efforts. They established nature reserves and national parks so by 2012 it included more than 25% of its land and 6% was reserved for indigenous people. To reduce deforestation the government has eliminated subsidies for rangeland, instead it paid landowners to maintain or restore tree cover.

Portland Oregon (PG 627)

Urban areas are where more than half of the world's population lives. They have massive environmental impacts especially on the surrounding areas due to urban sprawl or due to large amount of food it needs. Most urban areas are unsustainable and are rapid growing centers of poverty like in Bangladesh. Portland on the other hand is an example of a sustainable urban area. For Portland to become more sustainable it needs to increase energy efficiency, to compost or recycle its MSW and to preserve its parks and wooded areas to protect the habitats of animals. Another large part of pollution in cities is the need for cars which Portland decreased by increasing the amount of bike paths and making it more difficult for cars to park and drive in the middle city area making it easier to use public transport. They also reformed their public transport to follow stricter times and make it more reliable. Finally, Portland has reduced urban sprawl which harms the surrounding ecosystems of a city through habitat fragmentation and increased human activity by bringing all the stuff a person needs in one area so they don't need to travel as much making it a much more enticing place to live.

Water's Unique properties (PG 64)

Water has many unique properties that enable life to live in the world. Firstly it has hydrogen bonds which is a strong bond that lets it exist as a liquid at a larger range of temperatures and it lets water act as a greenhouse gas by storing and releasing heat regulating the world at a steady temperature. Next since it stores lots of heat as a greenhouse gas it changes temperature slowly protecting living organisms from temperature change. Water also acts as a universal solvent and dissolves many compounds which lets it carry nutrients and flushes waste products. Water also filters out UV light protecting vulnerable phytoplankton from UV radiation. Water also has adhesion and cohesion letting it travel up from the roots of plants and do many other important things. Finally, water expands as it freezes which enabled life to start in the first place on land because without water expanding and creating cracks in the soil, the soil would be far too rocky for plants to be able to grow on it.

Invasion of the Cane Toads

When beetles began devouring sugar cane fields in Queensland, Australia, in the 1930s, farmers got desperate. They had an invasive species, so they decided to import another nonnative species to destroy that species. (Not a really good idea) Instead of controlling the pests, the toads have become pests themselves. A concealed deadly chemical defense system has transformed them into one of the world's top 100 invasive species that ravages Australia.

Bats and white nose syndrome

White-nose syndrome is an emergent disease of hibernating bats that has spread from the northeastern to the central United States at an alarming rate. Since the winter of 2007-2008, millions of insect-eating bats in at least 33 states and seven Canadian provinces have died from this devastating disease. The disease is named for the white fungus, Pseudogymnoascus destructans, that infects skin of the muzzle, ears, and wings of hibernating bats. The fungus thrives in cold and humid conditions characteristic of caves and mines used by bats. Scientists believe that White-nose Syndrome is transmitted primarily from bat to bat. There is a strong possibility that it may also be transmitted by humans inadvertently carrying the fungus from cave to cave on their clothing and gear. Source: https://www.usgs.gov/faqs/what-white-nose-syndrome?qt-news_science_products=0#qt-news_science_products

Zebra Mussels

With the increased trade between countries there has been an increase in the number of nonnative species introduced throughout the world. In many cases they become invasive species that plague an ecosystem because they have no natural predators. One example is the zebra mussel which plagued america. It came over from Europe on the hull of ships. It populated like Clair in 1988, then it spread to the Great Lakes and continued to spread. The Zebra Mussel population increased greatly in this time period as a result of the fact that their larvae travel downstream in flowing water and that the adult mussels can attach to many structures. They had no natural predators or competitors making them an invasive species that is hard to deal with. They damaged boats and engines. They were small enough to clog up pipes in engines. They also consume lots of plankton shifting the food web from other predators and consumers. It also can lead to Eutrophication in lakes leaving them devoid of life.


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