ES MODULE 2 chapter 25 FORESTS

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How should policy makers judge whether deforestation rates are too high?

-According to economists, deforestation should proceed until the rent earned from clearing forest land equals the benefits lost when that forest area is cleared -In short, excessive deforestation makes society poorer

What were the social consequences of the rising price of wood?

-As the price increases, consumers were forced to choose between heating and eating. -In response, the government established regulations regarding which trees industry and consumers could harvest.

Why are protected areas not always effective?

-Protected areas are too complicated. Important issues include how much area should be put under protection and which areas should be protected -Protected areas are not designed solely to stop deforestation. Protected areas also are designed to preserve biodiversity, enhance ecotourism, and preserve native cultures. Because of these complications, the effectiveness of protected areas cannot be evaluated using economic criteria alone -effectiveness of protected areas is limited because command and control strategies do not alter the economic incentives for deforestation. That is, farmers or loggers can still make money by deforesting land in protected areas. To control this incentive, governments must protect protected areas. Enforcement can be very expensive because protected areas often are very large

Existence value

-Forests have existence (intrinsic) value because many people say it is important to them that tropical rain forests or old growth forests continue to exist, even though they may never visit them

What are some of the indirect contributions of trees? climate control:

-Forests influence the rate at which Earth's surface absorbs solar energy and the rate at which water evaporates from the surface, which influence temperature and precipitation. -Trees leaves transpire and cool temperatures -The solar energy that would have warmed the surface is used to evaporate water (which has an immense cooling effect)

Does the government give forest land to settlers free of charge and if they do, how do settlers establish their ownership?

-Giving land to settlers free, instead of selling it to them, increases deforestation rates -Let's say land if not very conducive to agricultural, but the land was given to a rancher for free. The rancher could then do a little cattle raising and make a lot of their profit form selling the land.

What role do forests play in natural disasters?

-Hurricanes cause more damage on treeless landscapes -The combination of a treeless landscape and heavy rains increases the frequency and severity of floods and mudslides, which are great causes of the loss of lives and property

What caused huge loss of trees in western Europe and north America? What causes the regain of these forests?

-Industrial revolution -In temperate forests, succession has been able to regenerate forests in areas abandoned by farmers causing afforestation.

How does sampling bias influence the way we try to measure deforestation.

-Many estimates for forest area are generated by local governments, industry, or conservation groups. Each group has an incentive to distort estimates -Sampling bias occurs when a sample is collected in such a way that some members of the intended population are less likely to be included than others -To estimate deforestation rates accurately, scientists need to randomly sample parcels of forest land from total forest area and determine the fraction that is deforested -Tropical rain forests cover vast areas, but only a small portion can be visited by those charged with estimating rates of deforestation. To estimate deforestation rates, scientists sampled parcels that they could reach by roads. But the fraction of parcels that are deforested along roads is likely to be greater than the fraction of parcels that are deforested far from roads

Market based mechanism forests:

-Once the value of ecosystem services is known, finding a ways to charge these prices to those who would clear a forest lies at the heart of policy aimed at managing deforestation -One way to charge for the value of ecosystem services is a conversion tax. A conversion tax charges those who would convert a forest to an alternative use. Ideally, this tax would equal the value of ecosystem services lost when the forest is cut -Instead of a tax, it may be possible to preserve the forest by paying landowners an annual fee that is equal to the value of the ecosystem services generated by their forest. If these payments are greater than the rents they would earn by converting the forest to agriculture, they would preserve the forest

How do owners establish their rights to land?

-Owners have to prove that they made their land productive. -"Productive use" often required that forests be cleared and converted to another purpose such as agriculture

How can forests influence albedo and thus temperature?

-Replacing portions of the Amazon forest with pasture reduces albedo, which warms local temperatures. -In the central portion of the United States, replacing forests with agricultural fields increases albedo and transpiration, which cools summer temperatures.

Affluence and deforestation

-Rising incomes in developing nations in general and cities in particular allow consumers to purchase to purchase more good and servies. -Increasing affluence allows consumers to buy more food, especially meat. -raising livestock requires more land than growing grains because chickens, hogs, or cattle must eat several kilograms of plant material to produce a kilogram of meat

What are some of the intergenerational conflicts about economic rates of deforestation?

-The current generation enjoys the economic benefits of deforestation. Future generations will not enjoy these benefits but will suffer the loss of ecosystem services. Because they are not yet born, future generations do not get to choose the rate of deforestation -For example, our ancestors deforested much of the United States. Some of these efforts have increased our economic standard of living. Would you have preferred our ancestors to cut less forest if it meant a lower standard of living? If so, how were our ancestors to know your preference?

debt for nature swap

-The developing nation uses some of the money that it would have used to repay its debt to designate a portion of its forests as a national park where timber harvesting, agriculture, and mining are not allowed. -Indigenous people are allowed to live there and are encouraged to maintain their lifestyle. -In this way nongovernmental organizations achieve their goal of slowing deforestation. -In return for the setting up of the park, the nongovernmental organization forgives the loan. -That is, the developing nation no longer has to pay back the portion of the loan that the nongovernmental organization bought from the bank. -This reduces the developing nation's debt burden. Debt relief increases the funds that are available to improve the material well-being of the country's inhabitants

What happens to the price of wood as deforestation increase?

-The growing demand for wood caused wide areas of deforestation which reduced supply. An imbalance between supply and demand caused wood prices to increase significantly.

Briefly describe deforestation and original forest cover in the three following geographical regions: -Asia and Africa -Russia, Europe, North and Central America -South America

-The largest fractions of original forest cover have been eliminated here. Especially in tropical areas -a greater fraction of the original forest remains here and succession in temperate forests has reestablished some areas of the disturbed forest. -still has a significant portion of its original forest area

Selective harvesting high-grading

-The process of cutting individual trees or small groups of trees. -high-grading harvests only the trees that give the highest immediate economic return -Individual trees are chosen by species or diameter. This practice often is used because it generates cash for the owner in the short term; but these benefits sometimes are offset by long-term losses.

But who would pay the land-owners for the ecosystem services that the forest provides?

-This question arises because it is difficult to identify the consumers who benefit from ecosystem services and to charge them for the ecosystem services that they use

In what ways was food important for ship building in the 17th and 18th century

-Trade was super important at this time period -Trade profitability depended mostly on the size and speed of ships -Bigger ships could carry more cargo and faster ships could make more trips -Ship size and speed was dependent on the amount of and size of trees available (there was no way to join pieces of wood together strongly so it really was dependent on the largest tree they could get their hands on)

In Derbyshire, England, about 93% of trees were cut down. Why did the forest area decline so quickly?

-Wood was used for a variety of economic purposes -Used wood as a source of energy to produce a variety of materials such as glass, copper, and iron. -To heat homes, cook foods, produce paper, and build homes.

When a firm wishes to harvest trees from a government forest, it must obtain a timber concession. What is that?

-a contract that defines the rules for harvesting trees -To prevent firms from controlling large areas of the forest for long periods, timber concessions often run for relatively short periods -Under these conditions firms have little incentive to consider long-term costs and benefits. Instead they tend to cut as many trees as they can during the concession period

-many environmentalists are especially critical of clear-cutting. What is that?

-a practice in which all commercially valuable trees are harvested at the same time -In many cases clear-cutting generates severe environmental damage such as soil erosion, the loss of timber production for many decades until trees regrow, the loss of habitat, and the possibility that unwanted plant species will become established -established. But clear-cutting also has some advantages, which include reducing the cost of harvesting trees and speeding the regrowth of tree species whose seedlings cannot grow in the shade, such as red pines

What are the two ways wood from trees are used?

-as a raw material for the production of goods and services -as a source of energy -About half and half globally (but developed nations use it more as a raw material and developing nations use it more as a source of energy)

How do developing nations primarily use wood?

-as a source of energy for heating, cooking, and lighting -Developed nations get fuel by other resources, don't use wood for energy like developing nations do.

How do forests affect the flow of local streams and rivers

-by regulating the rate at which soils absorb and release water. -soils covered by trees generally store more water than bare soils, releasing that water steadily throughout the year. This will supplement ongoing precipitation and allow streams to flow year-round, instead of goin through periods of drought.

Technology and deforestation

-changes in timber harvests or agricultural production -technical changes that reduce transportation costs(are the price paid for moving capital, labor, or other inputs into the forest or moving agricultural goods or timber out of the forest) -Transportation costs are determined primarily by the transportation infrastructure, which includes canals, roads, railroad lines, and ports. -Even the most fertile agricultural land or productive timber area has little economic value if the costs of transportation are too high

We have moved away from using wood in things such as the handles of tools or your car dashboard with the rise of metal working and plastic, but wood still remains an important raw material. Why?

-construction for structural support, walls, and roofs -paper

Even if society cannot price ecosystem services and have consumers pay for them, deforestation rates can be slowed by...

-eliminating subsidies that inflate economic benefits

How did the use of wood follow changes in technology and affluence?

-for most of human existence wood was the more important nonfood resource -Many hunting tools were made out of wood -As technical capabilities increased, so did the use of wood. People fashioned wood into furniture, houses, and ships

What are some of the indirect contributions of trees? storing carbon:

-forests affect climate indirectly by storing great quantities of carbon -tons). If all of this carbon were released to the atmosphere, the atmospheric concentration of CO2 would approximately double

What makes burning wood hard? So what do we do with wood to solve this issue?

-freshly cut wood has a high water content -also makes wood heavy and expensive to transport -Wood is split and left to dry. Then it has more energy content -Also, wood could be converted to charcoal by heating it above 300 in the absence of air. But, advantages are offset by the large amounts of wood that are needed to produce charcoal are very high

The relationship between population and deforestation

-growing human population increases the demand for wood and food, and so population growth is responsible for a portion of deforestation -In other nations population growth doesn't affect deforestation as much, here agricultural products are the driving force of deforestation.

What are some of the indirect contributions of trees? habitat for biodiversity:

-most of the world's terrestrial species are found in forests, especially tropical rain forests. -Deforestation reduced biodiversity by reducing the area covered by forests?

-What does the amount of rent generated by a unit of land depend on?

-physical characteristics - Highly productive forests will generate higher rents because they provide more timber or can be used to grow more food than less productive lands -But the amount of rent generated also depends on population, affluence, technology, and institutions. -The IPAT equation can be used to estimate this

Commend and control policies forests: protected areas:

-protected areas: are a clearly defined geographical space, recognized, dedicated, and managed, through legal or other effective means, to achieve the long term conservation of nature with associated ecosystem services and cultural values.

Lots of people know that trees provide timber, but are some of the important environmental services they support?

-regulating the climate -holding soil in place -These services do not have a price; and so the loss of environmental services is often ignored by those who harvest timber.

Shelterwood method

-removes trees in a series of two or three partial cuts -This method is designed to simulate a natural disturbance that leaves a stand of trees that are nearly the same age -These trees provide shelter that speed the regrowth of shade tolerant trees, such as red oak or American beech -In addition, these trees provide habitat for wildlife. Despite these advantages, harvesting via the shelterwood method is difficult because it requires expert management

What are some of the indirect contributions of trees? soil retention:

-roots hold soil in place, and trees transpire lots of water. -If this water remains in the soil, rainstroms would be more likely to saturate the soil, and allow water to move horizontally across the surface and erode soil. -Trees also protest soil from wind

What are some of the social costs of eroded soil?

-some eroded soil washes into nearby rivers and streams, where soil is suspended in the running water and increases its turbidity -Turbidity reduces photosynthesis and ultimately net primary production. -Soil particles also influence the gills of fish, which reduces the survival rates of young fish. -eroded soil particles also reduce the productivity of economic infrastructure. Where stream flow slows, soil particles accumulate on the bottom, which is termed siltation. Siltation kills small benthic organisms, reduces the storage capacity of reservoirs, and shortens the life spans of hydroelectric dams. Siltation also interferes with water transportation by making waterways shallower, which reduces the size of ships that can navigate the waterways

What are some of the indirect contributions of trees? oxygen:

But not in the sense that the forest is the "lungs of the world", but rather the oxygen we breathe was generated by plants about 400 million years ago. -Plants were spreading and when photosynthesis exceeds respiration, oxygen concentrations rise. When organic carbon was buried in sedimentary rocks, carbon wasn't able to be respired and oxygen was kept at a high concentration

In response, the notion of sustainable forest management has been expanded into the concept of ecosystem management. What is that?

Ecosystem management seeks to balance human needs for wood as a raw material and an energy source with the forest's provision of ecosystem services. To do so, ecosystem management seeks to ensure a sustainable supply of timber while conserving soil and water, sustaining the resistance and resilience of the forest, supporting the food security of indigenous people, conserving biological diversity, and so on

Describe the positive feedback loops regarding forest fires that also increase deforestation?

Fires destroy trees, reducing evapotranspiration and adding aerosol particles to the atmosphere, which increases the ability of clouds to hold water. Both factors reduce rainfall, which leads to drought, which increases the likelihood of fires that deforest land

How does the construction of roads and the clearing of land by the timber sector create a positive feedback loop?

New roads make it easier for farmers to enter the forest and clear land for agriculture, as well as facilitating the transport of agricultural goods for domestic consumption and export

How do roads contribute to deforestation

Over time the land along the main road becomes deforested, and feeder roads spread outward from the main highway. Deforestation follows the feeder roads. Eventually deforestation spreads outward from the feeder roads. This creates a fishbone pattern of deforestation

Soybean rent versus ecosystem services in the amazon. When should forests be converted?

Simply converting forests to soybean fields in all areas where soybean rents are positive would reduce the total economic gains from deforestation by 5 to 10 percent. To avoid these losses, forests should be converted to soybean fields only where the rents earned by growing soybeans are greater than the value of ecosystem services generated by the intact forest

During the 1980s and 1990s the Brazilian government offered free land in Amazonia to settlers. A settler could claim three times the amount of land that he or she cleared. So how did this increase deforestation?

To maximize their claims, settlers burned extensive areas of the forest. These fires were partially responsible for the rapid rates of deforestation in the Amazon during the 1980s

If timber companies paid the full costs of road construction, lower rents would slow deforestation. How come they don't have to?

government subsidies can make poor investments profitable. Subsidies take many forms, including tax reductions, low-interest loans, or government services that are priced below cost. For example, governments often build roads into the forest at little or no cost to timber companies

deforestation

the action of clearing a wide area of trees.

When does Deforestation occur?

when and where the money earned from harvesting timber or converting a forest to agriculture is greater than the money earned by leaving the forest as is. These earnings are termed rent, which often is measured by the difference between the revenues earned by selling wood and the cost of harvesting wood. -pasture. If rents become negative in existing agricultural areas, farmers will abandon their land. Once abandoned, the forces of succession allow the forest to regrow.

intensive land use

which are systems that use a lot of capital per unit area. For example, landowners are reluctant to set up tree plantations because a neighbor's fire could destroy their investment

But there is considerable controversy about what constitutes a sustainable forestry practice. For those in the timber industry the term implies a sustainable yield of timber. What is that?

which means harvesting timber no faster than the rate at which trees produce new supplies. But timber is only one of the benefits generated by forests. For example, tree plantations can generate a sustainable supply of timber. Yet many people argue that replacing forests with tree plantations is not a sustainable forestry practice because tree plantations generate fewer ecosystem services than the forests they replace. For example, some tree plantations reduce an area's water supply. Tree plantations support fewer species, which also reduces the forest's ecosystem services

Instead the potential for accidental fires encourages extensive land uses. What does that means

which use greater areas of land per unit capital, such as cattle ranches. Extensive land uses tend to accelerate the rate of deforestation


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