Earth Science Unit 3
___ areas tend to have a higher population in a smaller area.
urban
What is the definition of greenhouse gases ?
gases that trap heat from the sun in Earth's atmosphere
What is the definition of crop rotation ?
planting a different crop each year
What is the definition of tillage ?
plowing or digging soil before planting crops
Outside of a city or town, flooding can have both
positive and negative impacts on the environment. Some of these impacts are restricted to rural areas and others have consequences for residents of a community.
A farm on a hillside might rely on ____ and create flat steps on the slope.
terrace farming
Which of these properties of sand did researchers discover can impact the longevity of a beach nourishment project?
texture
What is the definition of sustainability ?
the ability to use a resource so that it is not depleted or permanently damaged
What is the definition of water table ?
the boundary between unsaturated ground and saturated ground
It is important for green roofs to be designed and installed properly. This keeps
the building underneath safe and secure from leaks and damage. Proper installation also ensures the longevity of the plants on the roofs.
In 2006, the University of Michigan researched the difference in cost between a traditional roof and a green roof. According to their research,
the cost of a conventional roof covering 21,000 square feet was about $335,000, while the cost to install a green roof was about $464,000. This initial cost difference could be considered a disadvantage. However, the research also revealed that the overall lifetime savings of a green roof was about $200,000. Most of the savings came from decreased energy needs for the building.
What is the definition of agroforestry ?
the intentional use of trees and shrubs in farming
The price tag for the new and improved flood mitigation projects in New Orleans was hefty. In total, the local, state, and federal governments spent more than
$20 billion on roughly 350 miles of levees, pumps, gates, and flood walls surrounding greater New Orleans. The Army Corps of Engineers alone spent $14.5 billion on projects. Because much of New Orleans is below sea level, flood mitigation projects will need to be constantly monitored and maintained. One 1.8-mile-long barrier in St. Bernard Parish will cost an estimated $2 million per year in maintenance.
Which of the following are environmental benefits of green roofs? Select the two correct answers.
- Green roofs can improve air quality. - Green roofs can absorb stormwater and release it slowly.
Soil analysis has many benefits:
- Optimize crop production. - Diagnose plant culture problems. - Improve the nutritional balance. - Apply the correct number of nutrients. - Protect the environment from contamination by runoff and leaching of excess fertilizers.
While green roofs provide a multitude of benefits, they are not without drawbacks. The two biggest concerns when developing a green roof plan are:
- cost of installation - maintenance costs
In summary, socioeconomic impacts of flooding might include:
- damage to structures and infrastructure - damage to land, products, and possessions - food shortages and increased food prices - loss of livelihood - relocation - disruption of routines and access to goods and services
In summary, there are many ways homeowners can protect their homes from floods:
- elevating the home - relocating furnaces, water heaters, and electric panels - installing check valves - sealing walls in the basement - using sandbags
In summary, environmental impacts of flooding might include:
- nourishment of the soil - improved plant growth in the future - the spread of pollutants - degradation of water quality - contamination of drinking water - disruption of food chain - groundwater recharging
Green roofs have many different layers, and each layer has a specific purpose:
- plants: the layer of vegetation visible to visitors of the green space - growing medium: a mix made up of materials that ensure a suitable growing surface - filter cloth: prevents growing medium and other materials from reaching drain - drainage layer: drains excess water off the roof - root barrier: helps protect membrane from being penetrated by roots - waterproof membrane: overall protection for building underneath
Intensive Green Roofs:
- use a wide variety of plants, possibly including large shrubs and trees - have a soil depth of 6 inches or more - have a dry weight of vegetation between 50 and 150 pounds per square foot - require significant structural support - require routine maintenance and have high start-up costs
Extensive Green Roofs:
- use low-growing plants such as mosses, herbs, succulents, and grasses - have a soil depth of less than 6 inches - have a dry weight of vegetation between 10 and 50 pounds per square foot - require relatively minimal maintenance and have low start-up costs
Most beach nourishment project have to be redone every
5-7 years
Once installed, the maintenance costs for a green roof include both time and money. Just as with any garden, a green roof must be consistently maintained. Watering plants, keeping them safe from pests, and ensuring the equipment is properly inspected are all part of the proper care of a green roof. According to the EPA, yearly maintenance costs for both types of green roofs can range from
75 cents to $1.50 per square foot.
In which situation would beach nourishment be a good solution to issues caused by beach erosion?
A beach experienced massive sand loss after a recent hurricane.
Combination:
A green space can provide benefits in more than one category at the same time. For example, a park might make commuting to work by bicycle more attractive, thereby promoting physical activity for better health and reducing the economic costs of driving a car. A rooftop garden can provide a habitat for insects while increasing the sense of well-being for those who work the garden. An apartment near an urban wood will have lower cooling costs and improved air quality.
What is the definition of alley cropping ?
a type of agroforestry in which rows of trees are planted in between rows of crops
What is causing beach erosion on Miami Beach?
Beach erosion is being caused by hurricanes that are common during the summer and fall months in Miami.
Which of the following is a potential drawback of using jetties to prevent beach erosion?
Beach erosion may increase on the downdrift side of the jetties.
How are beach nourishment and vegetation management similar in how they manage beach erosion?
Beach nourishment and vegetation management both bring in materials to help fight beach erosion.
How are vegetation management and beach nourishment similar in the ways they combat beach erosion?
Both relocate materials back to the shore.
Beach erosion is mainly a natural occurrence. While it is nearly impossible to prevent, finding ways to manage beach erosion is
a vital task that coastal cities worldwide are undertaking.
Green roofs are
a type of urban green space designed on the roof of a building or home. Green roofs are not simply potted plants on a roof. To be considered a green roof, the roof should be partially or completely covered with vegetation. A green roof also includes a growing medium, a drainage system, and a waterproofing structure.
Think about the differences in each city's location and the potential causes of future flooding. Why was a major approach in Grand Forks to move people away from the river, while the main approach in New Orleans was to build or reinforce structures?
Grand Forks has flat land located near a river. The city's main concern was the overflowing of the river onto the floodplain where houses were located. Moving these houses off of the floodplain helped mitigate future damage to homes. New Orleans is located next to the Gulf of Mexico. Its main concern was future hurricanes and storm waves. The city needed to build and reinforce structures in order to protect itself.
Why did Grand Forks undertake a major mitigation project based on relocating homes off of the floodplain?
Grand Forks is in a rural area with room for expansion away from the river. The cost to repair or rebuild homes on the floodplain would ultimately be more than the cost of relocating them. By moving the homes, the floodplain could return to its native state and do a better job of absorbing floodwater.
What might happen if damage occurred to the drainage layer of a green roof?
If the drainage layer was damaged, the excess water from the green roof might not be able to drain off the roof. This could cause leakage problems for the roof and the building underneath.
Consider the points made by the blogger. How do the benefits of flood mitigation compare to the costs for both Grand Forks and New Orleans?
In Grand Forks, many people had to relocate their homes as part of the flood mitigation efforts. Some had to move to a completely different home. The town spent $409 million on projects to protect itself from flooding. However, the benefits of protection from future floods and as well as not needing to relocate homes will almost certainly outweigh the cost of flood mitigation. In New Orleans, over $20 billion was spent on flood mitigation projects. The benefits of these projects include the prevention of loss of life and property. Important industries such as fishing and tourism benefit from people's confidence in the flood mitigation projects' ability to keep the city safe.
Why is money put into expensive flood mitigation projects rather than paying for the cost of repairing damages caused by flooding?
It is cheaper to pay for flood mitigation projects than to pay for damages resulting from flooding. Studies have shown that $1 invested in flood mitigation can produce $6 in economic return.
Why is it important for green roofs to be properly installed with all the appropriate layers?
It is important to properly install green roofs because each layer has a purpose. A missing or improperly installed layer would cause the green roof to not work properly and possibly leak, damaging the building underneath.
How did the Great Flood of 1993 impact the socioeconomics of the Midwest?
Millions of acres of farmland became unusable for years.
Why were the mitigation projects in New Orleans primarily focused on building and improving physical barriers?
New Orleans is an urban city with less ability to relocate homes. Its location near the Gulf of Mexico puts it at risk for storms with strong winds that cause seawater to blow inland and that stress physical barriers. Strengthening physical barriers offers the best protection for the residents.
How are waves related to shifting shorelines?
Waves can cause shifting shorelines.
All soil is not the same. Soil is composed of
a matrix of minerals, air, water, organic matter, and countless organisms. Each component is important for supporting plant growth and chemical decomposition. When organic matter decomposes, nutrients become available for plants to use.
Beach nourishment involves
adding sand and sediment to a beach. Unlike structures that help to keep existing sand and sediment on the shores, beach nourishment replaces what has been lost. It helps to create new natural environments, rebuild sand dunes, and protect sediment volume during sea level rise. In some areas, beach nourishment is the preferred method over hard structures for fighting erosion when the threat of flood or sea level rise is not prevalent. However, beach nourishment is a very expensive strategy. It requires the pumping or trucking of sand onto beaches. In some cases, this can cost millions of dollars. It is also not a long-term solution to the problem of erosion.
Rain forests are home to millions of species of plants, animals, and insects. However, as the human population increases, more and more rain forest land is used for
agriculture. Farmers need to balance the need for expanding farm lands with the potential impact that many farming techniques have on the region.
Farmers using ____ use trees and shrubs to provide nutrients and protection for their crops.
agroforestry
Green roofs can improve the health of residents who visit the roofs as well as those who don't. Green roofs improve
air quality by absorbing pollutants and carbon dioxide, and producing oxygen. They help regulate the climate of a city, reducing extremes in temperature. Green roofs have been shown to promote mental health and relaxation for those who spend time in them, and green roof gardens can also provide a source of fresh, local produce.
The rows of trees used in ____ provide shade for the crops growing between them.
alley cropping
Green roofs can protect and maintain biodiversity by
allowing many different types of plants to coexist together. These plants can provide crucial habitats for insects. Urban green roofs also help to replace green spaces that were lost to buildings and infrastructure.
What is the definition of a quifer ?
an area of rock that absorbs and holds water that exists below the water table
What is the definition of aquifer ?
an area of rock that absorbs and holds water that exists below the water table
While some areas are more prone to flooding than others, floods can and do occur anywhere in the world. Floods occur when
an overflow of water overtakes land that is usually dry. This typically occurs after heavy rains or snowfalls when existing drainage can't handle the increased amount of water. Hurricanes, large storm waves, and tsunamis can also cause floods.
The well provided access to water from the ___.
aquifer
The Federal Emergency Management Agency (FEMA) provides
assistance to individuals who have suffered losses due to federally declared disasters. In 2018, it also provided $70 million to support flood mitigation efforts in communities that experience frequent losses of property due to flooding. FEMA estimates that every dollar spent on disaster mitigation results in a savings of six dollars on disaster response.
Singapore is a city-state with a population of over 5.6 million and a population density of about 21,700 people per square mile. It has an area of 278.8 square miles, which is about half the size of Los Angeles. Despite being small and densely populated, Singapore is striving to
be a leader in urban green space, and sustainable and green practices. "Garden City" is the nickname for Singapore, and is also the name of a program launched in 1967 that sought to make Singapore a highly livable city filled with greenery. Today, the Sustainable Singapore Blueprint provides a framework for sustainability efforts through 2030.
Because of erosion, beaches have become narrower and the elevation lower. Less sand simply means less beach. Shorelines continue to shift, or move, inland as beach erosion occurs. In places that are uninhabited, shifting shorelines mean
beaches are created farther inland. In a place with human population growth, this results in narrower beaches, such as the one in the picture. Many beaches are completely lost to erosion
Soil and forests store carbon through a process known as ___.
carbon sequestration
Responsible homeowners take steps to protect their assets from floods. First and foremost, homes in flood-prone areas should
carry flood insurance to help with the cost of possible damages. Beyond that, homeowners need to ensure that their properties are well-prepared to withstand some, if not all, potential flood impacts. Depending on location, there are different ways homeowners can protect their properties.
What is the definition of ocean current ?
continuous movement of seawater
If a house or building is not suitable for green roofing, it may require special modifications. In addition to this cost, the installation of the green roof layers can
cost thousands of dollars more than a regular roof. The Environmental Protection Agency (EPA) estimates that the cost of installing an extensive green roof is about $10 per square foot. For intensive roofs, the cost is about $25 per square foot.
In addition, green roofs can help with
cost-saving efforts. Green roofs tend to last longer than traditional roofs, which helps reduce the cost of replacements. They also act as natural insulation, keeping heat out during the summer and inside during the winter. They increase the energy performance of buildings, as cooling and heating costs can significantly drop in buildings with green roofs. They also absorb and then slowly release stormwater, preventing runoff that can overwhelm and damage a city's sewer system.
What is the definition of terrace farming ?
creating flat steps for farming on slopes of hills or mountains
___ protects the health of the soil because different crops use different nutrients.
crop rotation
Local governments have a responsibility to their citizens to
develop flood mitigation techniques that will protect towns and their infrastructures from flooding. Depending on the area, cities enforce different rules and regulations to help with flood mitigation.
While green roofs are typically visually pleasing, they provide many other advantages as well. Urban green roofs provide both
environmental and economic benefits to a city, and health benefits to its residents.
___ caused an overgrowth of algae in the lake due to excessive nutrient levels.
eutrophication
A hotel wants to develop a green roof that is easy to maintain. The roof can only support about 20 pounds per square foot. Which is the best type of green roof for their space?
extensive
There are two types of green roofs:
extensive and intensive.
A town uses ___ to control how and where floodwater moves.
flood mitigation techniques
The federal government has a responsibility to the citizens of the United States to assist with
flood mitigation. Nationally, the U.S. Army Corps of Engineers (USACE) helps state and local governments to reduce damages from floods and promote flood management. Additionally, the USACE takes action to educate the public about flood risks and ways that citizens can decrease their risks. The USACE also manages about 700 dams across the country, including in Puerto Rico. Flood control dams work by trapping floodwaters. Dams release floodwater in a controlled manner to the river below the dam, or they store or reroute water for other purposes.
There is no question that flood mitigation efforts are expensive, and yet it is cheaper to
fund efforts to prevent flooding than to pay for damages after a flood has occurred. Studies have shown that $1 invested in flood mitigation can produce $6 in economic return. Effective mitigation strategies can guard against the loss of property, infrastructure, businesses, and lives. These strategies can also provide a sense of safety for current residents and help attract new ones, thus ensuring a stable tax base.
Carbon dioxide is a ___ that traps heat in the atmosphere.
greenhouse gas
What is the definition of intercropping ?
growing multiple crops on the same plot of land
The population of New Orleans, which was 484,674 at the time of Hurricane Katrina, dropped by
half soon after the flooding. It has since increased to 369,000, but many who left because of Katrina never returned. The city has created improved disaster plans to respond more quickly in the event of a future flooding in order to better protect and retain its citizens
The greatly improved flood mitigation system has provided
higher confidence in the city's ability to avoid another flooding disaster on the order of Katrina. The economy of New Orleans has improved. Unemployment, which spiked to 15.9% immediately after the flooding, dropped to 6% by June of 2016. Tourism, a major industry in the area, has returned to 2004 levels.
While the amount of money that it takes for a town to recover can climb into the billions of dollars, flood recovery can ultimately result in
improvements to a community. Tourism dollars that were lost immediately after a flood might someday be regained by building recreational areas in newly created floodplains. Buildings that are rebuilt or replaced can include improvements that are attractive to homeowners or business owners.
Flooding often causes damage to
infrastructure such as roads, bridges, airports, communication systems, power plants, and schools. This means that even those whose homes or places of business were spared from the flood still experience socioeconomic impacts. The flow of goods and services into and out of the community may be disrupted for a long period of time. With limited access to important products, loss of customers, or loss of a home, many people find it necessary to relocate or rebuild. Relocation and reconstruction disrupt the social and economic norms that existed prior to the flood.
The population of Grand Forks has regained its pre-flood levels, despite
initially dropping by over 3,000 in the early years following the flood. Residents and tourists alike take advantage of the recreational opportunities of the Greenway, a newly designed town square, and a new convention center that can also serve as a disaster-staging area. The leadership of Grand Forks has become a model for other communities in the area of disaster recovery and preparedness. The city's flood mitigation techniques were tested in both 2009 and 2011 when the Red River again rose to dramatic levels, but, unlike 1997, the city experienced no flood damage.
Growing several crops on the same plot of land, called ___, can increase output.
intercropping
The farmer planted crops in __, a balanced mix of sand, clay, and silt.
loam
Flooding in agricultural areas can mean
loss of crops, livestock, equipment, and structures. Wet fields may make it difficult to harvest a crop or allow cattle to graze. Transportation of supplies to a farm or products from a farm may prove impossible. If agricultural production is severely impacted across a large area, food shortages might result, driving up the prices of particular products. Dramatic changes in routine cause stress for both humans and animals.
Flood mitigation strategies can have both benefits and costs. They can mean
lower costs for flood insurance, while also creating higher taxes. The projects themselves provide employment, but their location may damage a business or industry. They can generate public spaces, such as the Greater Grand Forks Greenway, but also result in the relocation of homes. They can revitalize certain industries, such as tourism and fishing in New Orleans, but require continual maintenance costs.
Which of the following can be a challenge when implementing a green space?
making sure access is equitable
Floods are the
number one natural disaster in the United States. Flooding can occur in any part of the country, and no area is immune to the possibility of floods. In fact, about 25 percent of flood insurance claims come from areas of low to moderate flood risk.
When old flood mitigation strategies fail, cities must decide what strategies to use in the future. This section focuses on two cities
one inland and one coastal—that experienced severe flooding. After the flooding, both cities worked with FEMA and other organizations to implement new flood mitigation techniques . The new mitigation efforts have resulted in both costs and benefits.
A substance's ___ indicates whether it is an acid or a base.
pH
In total, $409 million was spent on flood mitigation efforts in the Grand Forks area. $22 million alone was spent on the Greater Grand Forks Greenway, which included the buyout or relocation of hundreds of homes. Some residents and businesses are still
paying off loans that helped them get back on track after the flooding.
What is the definition of socioeconomic ?
relating to a combination of social and economic factors
Which of the following is a way homeowners can protect their homes from floods?
relocating furnaces and water heaters
Floodwater contains more than just water. On the positive side, it can contain
sediment, organic material, and nutrients that nourish the soil, improving plant growth and improving the health of an ecosystem. On the negative side, it can contain debris that obstructs shorelines or pollutants that damage fields. One of the biggest concerns is that flooding will degrade water quality and contaminate the drinking supply that a community depends on. Floodwater can overwhelm sewage and water runoff systems.
Large floods can have
severe impacts on wildlife and biodiversity. Habitats might be altered or washed away. Food supplies might be diminished. Microbial communities and earthworms in the soil might not survive. A disruption at the bottom of a food chain can have impacts all the way up to the top of the food chain.
As beaches erode, shorelines can
shift inland
What is a potential benefit of using alley cropping?
slowing soil erosion
Floods can have ___ impacts, like increased food prices or decreased income levels.
socioeconomic
Nearly all major floods have
socioeconomic impacts, meaning the people in the communities affected by the flood experience both social and economic consequences. The degree of the impact depends on the extent of the flooding and the resulting loss of structures, possessions, livelihoods, or even lives.
The Federal Emergency Management Agency (FEMA) also works with
state and local governments to assist with flood mitigation. In addition to contributing funds to the costly recovery efforts after floods, FEMA works with communities to find solutions, such as flood diversion, to help reduce flood damages. Flood diversion includes rerouting floodwater from rivers, streams, or other bodies of water into green spaces (such as wetlands or floodplains) by means of canals and tunnels. Diverting water to green spaces helps reduce overflowing of rivers and allows the floodwater to infiltrate the soil and replenish aquifers . Ultimately, this can increase water supply and water quality.
A city develops an open green space in the center of town as a way to help with runoff. Which flood mitigation technique is the city implementing?
stormwater management
What is the definition of flood mitigation techniques ?
strategies to manage and control the movement of flood waters
Flood mitigation techniques are
strategies used to manage and control the movement of floodwaters. There are specific techniques and responsibilities that homeowners, cities, and state and federal governments can implement in order to assist with flood mitigation.
Companies that focus on __ seek to avoid depleting resources.
sustainability
The set of farming practices called ___ seeks to preserve resources for the future.
sustainable agriculture
Flooding is more likely in an area with a higher ___.
water table
The efforts include the following plans for green space:
- Increase the amount of park space, which was 16.108 square miles in 2015 or 6% of the city's land, to approximately 18.3 square miles in 2030. - Increase the number of households within a 10-minute walk of a park from 83% in 2015 to 90% in 2030. - Increase the number of "Community in Bloom" community gardens from 995 in 2015 to 2,000 in 2030. This is an increase of 101%. - Increase the amount of greenery on buildings from 0.278 square miles in 2015 to 0.772 square miles in 2030. This is an increase of 178%.
Management and maintenance of green spaces requires ongoing costs and decisions. What concerns might a city have with each of these features? park trails pesticide use green roofs
- Park trails typically require maintenance in the form of patching asphalt or adding gravel. In northern climates, they may require plowing in the winter. If safety is a concern, additional police officers may be required to patrol the trails. - Pesticide use can help minimize weeds and undesirable insects, but it may also kill pollinators like bees. Pesticides in runoff water can flow into ponds, where they increase the growth of algae and sometimes kill fish. - Green roofs require people to maintain them. The materials used, such as vegetation, waterproof sheets, and drainage pipes, may need replacement. The roofs may not be accessible to the disabled.
Beach erosion occurs when sand is removed from the beach and deposited in deeper waters offshore. There are many causes of beach erosion:
- human activity - ocean currents - storm waves
Which of the following are possible benefits of alley cropping in the rain forest? Select the two correct answers.
- increased biodiversity - maintenance of soil's nutrients
Which of the following are sustainable farming techniques? Select the two correct answers.
- rotating crops each year - planting trees in between rows of crops
Soils perform many important purposes in an ecosystem, including the following:
- serving as media for the growth of plants - modifying the atmosphere by emitting and absorbing dust and gases, such as carbon dioxide, methane, and water vapor - providing habitats for animals, such as grubs, worms, groundhogs, and mice - supporting organisms, such as bacteria and fungi, which are critical to cycling the matter on Earth - absorbing, holding, releasing, altering, and purifying most of the water in land-based ecosystems
Which of the following contribute to beach erosion?
- storm waves - ocean currents - human activity
What is the purpose of beach nourishment? Select the two correct answers.
- to replenish sand on a beach - to mitigate beach erosion for a period of time
You need to adjust the following criteria to produce a good crop:
- type of soil - Different types of soil retain various amounts of water for crops to grow, and the amount of water in the soil affects the nutrients that are available for the crops. - pH of the soil - It is important to remember that extreme or even moderate pH ranges, both alkaline and acidic, can be detrimental to crops and make soil toxic for future planting. - amount of fertilizer - Fertilizer provides nutrients for crops. However, overuse of fertilizers could have a negative impact on the environment.
Many beach erosion management strategies involve building hard structures to protect sand and sediment loss on beaches. These structures include, but are not limited to, the following:
-jetties - groins - seawalls - coconut coir logs
the process of beach nourishment:
1. Dredging begins with a ship offshore sucking up sand and water from the bottom of the body of water. 2. A vacuum-like tube pumps sand and water into a large container on the ship. 3. The water is filtered out and dumped back into the ocean. 4. The remaining sand and sediment is piped to the beach, where bulldozers and other machinery move the sand around and evenly place it on the beach.
Classify the sustainable farming practices by determining if its associated with a practice used in a desert, rain forest, or both.
Desert: - greenhouses - hydroponics Rain forest: - polyculture - agroforesty Both: - crop rotation
Beach Nourishment: Time and Materials
Each beach nourishment project can last months, closing parts of beaches as a result. Materials and equipment brought in to extract sand are heavy and costly, and workers toil around the clock to complete projects.
The benefits of green spaces fall into three categories:
Environmental Economic Health
How could San Diego's discovery affect future beach nourishment projects?
Future beach nourishment projects could use the findings to try and relocate more coarse sand to beaches.
Environmental:
Green spaces help to reduce both noise and air pollution. The trees and plants clean the air and produce oxygen. They help slow global warming by reducing the amount of greenhouse gases that are present in a city. Green spaces prevent soil erosion and provide a habitat for wildlife. They moderate the temperatures in a city by having a cooling effect on the urban heat island.
Health:
Green spaces provide multiple health and wellness benefits. They provide locations for exercise, relaxation, and social interaction. Community gardens provide healthy foods while increasing physical activity. Green spaces have been shown to reduce stress levels and depression for some people.
What conclusions can you draw about the impact this discovery may have on the long-term effectiveness of beach nourishment projects?
If beaches want sand to last longer on beaches, using coarser sand may be a good option.
What sustainable farming methods are used in your area?
Many farmers in my area plant cover crops to protect the soil from erosion. Some farmers in my area are using no-till farming techniques, which reduces disruption to the soil.
Do you think the methods used in your area are effective ways to address these farming challenges? Do the sustainable methods have any drawbacks?
Many farmers in my region report that these methods have reduced the amount of soil loss they experience each year. However, cover crops and no-till methods can increase the risk of pest problems and disease, so farmers need to plan ways to mitigate these risks.
How is beach erosion affecting the town of Miami, Florida?
Miami's beaches are becoming more narrow and shorelines are shifting inland. The city is having to spend millions of dollars to fight beach erosion.
Why does a plant care what soil it is in?
Plants get nutrients and water from the soil through their roots. Not all plants need the same amount of nutrients or water, so different plants will grow well in different types of soil. Farmers and gardeners will adjust additives to the soil to try to best match the plants' needs.
What farming challenges does your region face?
Rainstorms and strong winds in my region cause erosion. Erosion reduces the amount of crops that farmers are able to produce each year.
How are soft strategies different than building a jetty or groin?
Soft strategies replace sand or vegetation on the beach and do not use hard structures. A jetty or groin works to keep sand on the beach and uses hard structures.
Beach Nourishment: Cost
The cost of beach nourishment is extremely high. Each project ranges in the millions of dollars. Projects are federally and locally funded, spreading the cost burden.
Economic:
There are several economic benefits of green spaces. They increase the property values of buildings and homes in their vicinity. Because green spaces have a cooling effect, they can help to reduce the energy costs for neighboring buildings. They absorb rainwater and lower the costs of stormwater management.
Which of the following effects do shifting shorelines have on beaches?
They cause narrower beach areas.
Beach Nourishment: Long-term Effectiveness
Unlike hard structures such as jetties or seawalls, beach nourishment is not permanent. While the short-term outcome produces wider beaches, bad weather and hurricanes can continue to erode beaches. Beach nourishment has to be redone approximately every 5-7 years.
What is the definition of pH ?
a measure of how acidic or basic a substance is
What is the definition of beach nourishment ?
act of adding sediment and sand to a beach to elevate and extend the shoreline into the water
When nutrients in fertilizer, like nitrogen and phosphorus, are added to soil but not picked up and used by the growing crop, they enter local waterways through runoff or groundwater. The result is
eutrophication , or excessive nutrients in a water body causing overgrowth of algae, plankton, and other microorganisms. Basically, the excess nutrients can cause major algae blooms. The algae bloom blocks sunlight from other underwater plants and depletes the water of dissolved oxygen as it decays. This, in turn, harms all other aquatic life and can cause the death of aquatic organisms from lack of oxygen.
What is the definition of eutrophication ?
excessive nutrients in a water body causing overgrowth of algae, plankton, and other microorganisms
Agriculture provides food for an ever-increasing population. Sustainable agriculture is
farming by methods that meet a community's current needs while preserving and protecting resources for the future. These methods vary based on the land and water resources available in a given area, but sustainable methods can help farmers produce enough crops while reducing deforestation, erosion, and water usage, and sustaining the land for future farming.
What is the definition of sustainable agriculture ?
farming that meets current needs while preserving and protecting resources for the future
Beach nourishment is a common method for
fighting beach and shoreline erosion in the United States. Beach nourishment is the act of adding sediment and sand to a beach to elevate and extend the shoreline into the water. This sand and sediment is usually dredged from offshore.
For example, trees are able to absorb and store carbon dioxide from the atmosphere through a process known as carbon sequestration . When farmers plant trees for alley cropping—or even maintain existing forests in more complex forms of agroforestry—they allow for
greater carbon storage. When more carbon dioxide is stored, less carbon dioxide is in the atmosphere, which slows down the process of climate change.
The Skyrise Greenery Incentive Scheme, introduced in 2009, has aided in
greening over 110 older buildings, resulting in green roofs, edible gardens, recreational rooftop gardens, and walls of greenery. New construction also focuses on producing buildings with green space. A recent public housing project built seven 50-story towers that are connected with gardens on both the 26th and the 50th floors.
The sustainable practice of intercropping involves
growing multiple crops on the same plot of land. ( Inter- means "between," so intercropping often involves planting rows of one crop in between rows of another crop.) With alley cropping , rows of trees are planted in between rows of crops. Intentionally using trees and shrubs in farming via agroforestry is increasingly popular in rain forest regions.
Jetties and groins are
hard structures built perpendicular to the shoreline. They both protect from erosion caused by waves and current. Groins tend to be smaller, shorter structures, whereas jetties can reach farther out into the ocean. While both are viable management options, they can actually cause some erosion in places as sand piles up on the updrift side of the structure, resulting in less sand on the downdrift side. Erosion caused by jetties can be severe with unintended consequences for beaches on the downdrift side of the jetty. Because of this, multiple jetties have to be built to help reduce this effect.
Human activity can cause and sometimes accelerate erosion. Building close to the coast can
have an effect on beaches and speed up erosion. Sand dunes, which separate low-lying beaches from higher grounds, can be damaged during the building process. These dunes help to prevent water from going too far inland. If the dunes are damaged, water is able to flow inland, causing shorelines to change.
What is the definition of urban ?
having to do with a town or city
Which issue does terrace farming help solve?
heavy rains washing away soil from mountainous farms
The first project of beach nourishment was
in 1922 at Coney Island, New York. Since then, at least 970 projects have brought sand to more than 6,050 kilometers of U.S. shoreline along the Atlantic and Gulf coasts. When beaches are eroding, beach nourishment can protect people and property from the effects of hurricanes and coastal storms. Many projects in the United States are responses to strong hurricane erosion similar to that shown in the images above of North Ocean City, Maryland.
Which of the following is a disadvantage of rain forest agroforestry compared to slash-and-burn farming methods?
increased start-up costs
The task of moving sand from one location to another is an expensive feat. It requires
machines, manpower, and time in order to pump sand from an offshore location and relocate it to the beach.
Depending on the size of the beach, the process of beach nourishment can take
many months. Myrtle Beach, South Carolina started a project in August 2018. The project was projected to cost $34.8 million and involve dumping 1.4 million cubic yards of sand over 14 miles of beach. The timeline outlines the beach nourishment project for the city of Myrtle Beach, South Carolina. For this project, operations occurred around the clock. Pumping moved along the shoreline at a rate of 200-300 feet per day, leaving most of the beach available for public use.
The beach nourishment process required more sand each time between the years of 1985-1998 in an effort to rebuild the beach. Hurricanes during this time period contributed to
massive sand erosion, causing beach nourishment projects to be continually undertaken to maintain beachfront.
The goal of sustainable farming practices is to
meet a community's current needs for food and commodities while protecting resources for future use. Sustainable farming practices are tailored to the specific needs of a region based on geography, climate, and the crops being cultivated. Farmers need to consider carefully the short- and long-term costs and benefits of each conventional and sustainable farming option.
Sometimes green spaces are created by
modifying or replacing native habitats. For example, a golf course may be constructed on the site of former prairie grasslands. While both can be considered green spaces, the golf course does not have the biodiversity of the grasslands.
Beach erosion is a worldwide problem. Beach erosion causes shorelines to
move inland or shift, impacting both the surrounding environment and human activity. There are many ways to help manage beach erosion and reduce its impacts.
Which of the following is one effect storm waves have on a beach?
movement of beach sand to a sandbar
What do beaches become due to erosion?
narrower
Farmers and gardeners use soil additives to
optimize conditions for plant growth. Fertilizers add important nutrients to the soil, and lime adjusts the pH , or how acidic or basic the soil is. Tilling loosens and aerates the soil. However, changing the soil composition and structure can have serious environmental impacts, especially on local waterways.
The size of the world's cities continues to grow. Over half of the world's population currently lives in cities. By 2050, that will increase to 70%. Because of this, green spaces, especially in urban areas, are more important than ever. Green space refers to land that is partly or completely covered with grass, trees, shrubs, or other vegetation. There are many benefits to green spaces. Some examples of urban green spaces include:
parks sport fields woods community gardens green roofs natural wetlands
Coconut coir logs are
placed along shorelines to help reduce beach erosion. They are round logs made of coconut fibers. They are biodegradable, safe for surrounding wildlife, and can help to stabilize the area long enough for natural seagrass to establish a strong root structure. However, this can take time to allow for growth of plant life and may not have immediate results.
Instead of building structures along beaches, other strategies can be
put into place to manage beach erosion. Vegetation management and beach nourishment, also known as soft alternative strategies, involve relocating materials to the beach and just offshore to help fight erosion.
What might a city find it necessary to do when initiating a beach nourishment project?
raise taxes
Tilled soil can lead to
runoff of extra sediments, which also reduces water clarity and smothers other underwater vegetation. Adding lime changes the pH of soil, which can affect the acidity of local waterways, thus negatively affecting aquatic life.
The three most basic types of soil are
sand, clay, and silt, but most soil is some mix of these. Soil that is a balanced mix of sand, clay, and silt is called loam .
What is the definition of loam ?
soil that is a balanced mix of sand, clay, and silt
Land itself is an important resource that needs to be maintained. Not only can soil be worn away through weathering and erosion, but
some conventional farming methods can deplete nutrients in the soil. For example, if farmers plant a single crop in a field over many years, nitrogen and other nutrients in the soil may be reduced, which can cause farmers to rely on commercial fertilizers or cause significantly reduced production in future years.
Seawalls are
structures built at the water's edge or slightly inland. They protect the land from rising tides as well as from strong waves or tsunamis. As a wave crashes into a seawall, the energy of the wave is reduced, causing it to pick up and erode less sand. While seawalls can be expensive to install, they have an additional benefit of flood protection.
What is the definition of beach erosion ?
the movement of sand and sediment from off the shore to deeper waters
What is the definition of polyculture ?
the practice of growing more than one crop in an area of land
What is the definition of carbon sequestration ?
the process by which carbon dioxide is removed from the atmosphere and stored
Clearly, beach nourishment is a temporary solution. It is only a matter of time before
the pumped sand is eroded again. However, on coasts such as North Carolina where hurricanes are more prevalent, the upkeep of a project such as beach nourishment is more constant. As shown in the data, Carolina Beach had to pump sand in every 3-4 years to keep up with beach erosion.
What is the definition of hydroponics ?
the use of water rather than soil to deliver nutrients to crops
The movement of waves and ocean currents removes sand from beaches. As waves crash against the shore, the current removes and carries the sand out to deeper waters. When a storm occurs,
the waves grow bigger and stronger. These storm waves deposit a lot of sand in large, offshore sandbars. It can take weeks and even months before this sand returns to the beach.
What is the definition of dredge ?
to dig or pull up
While green spaces are necessary and bring many benefits, there are challenges that come along with them. Creating a new green space means
trying to determine the size, placement, and type of green space that will provide the most benefits to the most people. Too often, green spaces are not created close to disadvantaged groups, such as people with low incomes. Often, the greatest challenge in creating urban green space is simply the lack of space. With most land already covered with buildings or pavement, proponents of green space must consider how to renovate buildings to add green roofs or walls. Since older buildings were not designed to bear the weight of green roof or wall materials and do not have adequate drainage systems built in, significant planning, money, and effort are required to successfully complete a renovation.
Another alternative to building hard structures is
vegetation management along shorelines. Vegetation management is similar to beach nourishment in that they both bring materials to the shore and beach to help fight erosion. Vegetation management works to maintain and bring in plant life around shorelines to help trap more sand and sediment and keep it on the beach. The thicker and larger the vegetation, the more sand and sediment build up over time.
What is the definition of shoreline?
where a body of water meets the land
