How Humans Influence Ecosystems

Which of the following human behaviours would most likely be found in a sustainable ecosystem?
1. The responsible use of resources, and the preservation of habitats
2. An unlimited exploration for, and export of, resources
3. The extensive use of natural ecosystems for agricultural purposes
4. Implementing a system of widespread urbanization and the construction of large vehicle corridors
The following photo shows a long stretch of highway running through a forest ecosystem. Tall fences may need to be erected in the future to prevent animals from being struck by passing automobiles.

What is the name of the effect this type of project can have on the original ecosystem?
1. Habitat fragmentation
2. Ecosystem loss
3. Habitat expansion
4. Ecosystem contraction
Why does soil degradation occur in areas that have undergone deforestation?
1. Topsoil is eroded by wind and water without plants and trees to hold the soil in place
2. Burning trees release large amounts of carbon dioxide, which poisons the soil
3. The large machines used to remove the trees create large ruts in the soil
4. Animal species that previously lived in the trees disappear, and therefore do not provide waste material necessary for healthy soil
An ecologist discovers a stream with many dead fish. Tests conducted on the water reveal high levels of cyanide have contaminated the water. What is a likely source of this chemical in the stream?
1. A gold mine upstream from the testing site
2. A pulp mill on the mountainside above the stream
3. An oil well beside a lake that the stream flows from
4. A deforestation project in the forest that the stream flows through
Arsenic is sometimes used in the lumber industry when making pressure-treated wood. Lumber mills that use arsenic may utilize sunflowers to absorb the arsenic that escapes into the surrounding ecosystem. What is the name of the process where industries minimize their ecological impact and restore ecosystems?
1. Reclamation
2. Reforestation
3. Overexploitation
4. Decontamination
Fifty years ago, hunters from several countries were responsible for severe reductions in the numbers of sperm and baleen whales. As a result, orcas began to hunt smaller aquatic mammals instead of the larger whales, greatly reducing the numbers of these species. Fewer otters, seals and sea lions allowed the population of sea urchins to explode, and as a result the kelp forests of the northern pacific ocean are quickly disappearing.

What is the name for actions like these, where a natural resource is depleted, causing far-reaching effects throughout many food webs?
1. Overexploitation
2. Extinction
3. Exploitation
4. Ecological catastrophe
Which of the following would be an example of traditional ecological knowledge found in British Columbia?
1. The controlled burning of grass and bushes, promoting new growth and attracting animals who feed on the new growth
2. The suppression of forest fires, allowing trees to grow large and the undergrowth to become thick and littered with dead forest litter
3. The storage of chemicals used in various industries being held in treatment ponds
4. Using machinery to aerate compacted soil to allow air to circulate into the ground, and also to prevent run-off erosion
Which of the following best describes reclamation?
1. A former mine site is developed to match the surrounding landforms, and topsoil that was removed before mining began is replaced
2. The site of a forest fire one year earlier has many grasses and a few small jack pines growing today
3. Farmland is aerated after several years of hosting large herds of cattle. Wheat is then planted in the same farmland
4. Pandas, which can no longer find enough bamboo to survive, are trapped to be raised in zoos
The genetic diversity of Atlantic cod has decreased greatly in the past 40 years. The fish are very susceptible to having a disease decimate their populations, and as a species they are very slow to adapt to changes in their environment.

During this same time period, the cod fisheries and related industries in Canada’s maritime provinces have collapsed. What may have caused both the loss of genetic diversity and the failure of the once-strong fishing industry?
1. The over-fishing, and therefore overexploitation, of the Atlantic cod population
2. The release of toxic chemicals into the Atlantic ocean
3. The destruction of northern Pacific kelp beds by sea urchins
4. The use of traditional ecological knowledge to count spawning cod
Which of the following would be a sustainable approach to land use to preserve natural habitats in British Columbia?
1. Some cities are developing industrial areas that include planting native species in large green areas such as parks
2. Some cities are building sprawling suburbs well outside the established downtown area and traditional city boundaries
3. Some mountain areas have been clear-cut, and steep switchback roads constructed to haul out timber
4. Some natural grasslands have been altered for agricultural purposes, including the introduction of large quantities of non-native crops

How Humans Influence Ecosystems - Section 3.2 Quiz